From 64ac24e738823161693bf791f87adc802cf529ff Mon Sep 17 00:00:00 2001 From: Matthew Wilcox Date: Fri, 7 Mar 2008 21:55:58 -0500 Subject: [PATCH] Generic semaphore implementation Semaphores are no longer performance-critical, so a generic C implementation is better for maintainability, debuggability and extensibility. Thanks to Peter Zijlstra for fixing the lockdep warning. Thanks to Harvey Harrison for pointing out that the unlikely() was unnecessary. Signed-off-by: Matthew Wilcox Acked-by: Ingo Molnar --- arch/alpha/kernel/Makefile | 2 +- arch/alpha/kernel/alpha_ksyms.c | 9 - arch/alpha/kernel/semaphore.c | 224 -------------------- arch/arm/kernel/Makefile | 2 +- arch/arm/kernel/semaphore.c | 221 -------------------- arch/avr32/kernel/Makefile | 2 +- arch/avr32/kernel/semaphore.c | 148 ------------- arch/blackfin/Kconfig | 4 - arch/blackfin/kernel/bfin_ksyms.c | 5 - arch/cris/kernel/Makefile | 3 +- arch/cris/kernel/crisksyms.c | 7 - arch/cris/kernel/semaphore.c | 129 ------------ arch/frv/kernel/Makefile | 2 +- arch/frv/kernel/frv_ksyms.c | 1 - arch/frv/kernel/semaphore.c | 155 -------------- arch/h8300/kernel/Makefile | 2 +- arch/h8300/kernel/h8300_ksyms.c | 1 - arch/h8300/kernel/semaphore.c | 132 ------------ arch/ia64/kernel/Makefile | 2 +- arch/ia64/kernel/ia64_ksyms.c | 6 - arch/ia64/kernel/semaphore.c | 165 --------------- arch/m32r/kernel/Makefile | 2 +- arch/m32r/kernel/m32r_ksyms.c | 5 - arch/m32r/kernel/semaphore.c | 185 ----------------- arch/m68k/kernel/Makefile | 2 +- arch/m68k/kernel/m68k_ksyms.c | 6 - arch/m68k/kernel/semaphore.c | 132 ------------ arch/m68k/lib/Makefile | 2 +- arch/m68k/lib/semaphore.S | 53 ----- arch/m68knommu/kernel/Makefile | 2 +- arch/m68knommu/kernel/m68k_ksyms.c | 6 - arch/m68knommu/kernel/semaphore.c | 133 ------------ arch/m68knommu/lib/Makefile | 2 +- arch/m68knommu/lib/semaphore.S | 66 ------ arch/mips/kernel/Makefile | 2 +- arch/mips/kernel/semaphore.c | 168 --------------- arch/mn10300/kernel/Makefile | 2 +- arch/mn10300/kernel/semaphore.c | 149 ------------- arch/parisc/kernel/Makefile | 2 +- arch/parisc/kernel/parisc_ksyms.c | 5 - arch/parisc/kernel/semaphore.c | 102 --------- arch/powerpc/kernel/Makefile | 2 +- arch/powerpc/kernel/ppc_ksyms.c | 1 - arch/powerpc/kernel/semaphore.c | 135 ------------ arch/ppc/kernel/semaphore.c | 131 ------------ arch/s390/kernel/Makefile | 2 +- arch/s390/kernel/s390_ksyms.c | 7 - arch/s390/kernel/semaphore.c | 108 ---------- arch/sh/kernel/Makefile_32 | 2 +- arch/sh/kernel/Makefile_64 | 2 +- arch/sh/kernel/semaphore.c | 139 ------------- arch/sh/kernel/sh_ksyms_32.c | 7 - arch/sh/kernel/sh_ksyms_64.c | 4 - arch/sparc/kernel/Makefile | 2 +- arch/sparc/kernel/semaphore.c | 155 -------------- arch/sparc/kernel/sparc_ksyms.c | 5 - arch/sparc64/kernel/Makefile | 2 +- arch/sparc64/kernel/semaphore.c | 254 ----------------------- arch/sparc64/kernel/sparc64_ksyms.c | 6 - arch/um/Kconfig.i386 | 4 - arch/um/Kconfig.x86_64 | 4 - arch/um/sys-i386/ksyms.c | 12 -- arch/um/sys-ppc/Makefile | 8 +- arch/um/sys-x86_64/ksyms.c | 13 +- arch/v850/kernel/Makefile | 2 +- arch/v850/kernel/semaphore.c | 166 --------------- arch/v850/kernel/v850_ksyms.c | 7 - arch/x86/Kconfig | 3 - arch/x86/kernel/i386_ksyms_32.c | 5 - arch/x86/kernel/x8664_ksyms_64.c | 6 - arch/x86/lib/semaphore_32.S | 83 -------- arch/x86/lib/thunk_64.S | 5 - arch/xtensa/kernel/Makefile | 2 +- arch/xtensa/kernel/semaphore.c | 226 -------------------- arch/xtensa/kernel/xtensa_ksyms.c | 9 - include/asm-alpha/semaphore.h | 150 +------------ include/asm-arm/semaphore-helper.h | 84 -------- include/asm-arm/semaphore.h | 99 +-------- include/asm-avr32/semaphore.h | 109 +--------- include/asm-blackfin/semaphore-helper.h | 82 -------- include/asm-blackfin/semaphore.h | 106 +--------- include/asm-cris/semaphore-helper.h | 78 ------- include/asm-cris/semaphore.h | 134 +----------- include/asm-frv/semaphore.h | 156 +------------- include/asm-h8300/semaphore-helper.h | 85 -------- include/asm-h8300/semaphore.h | 191 +---------------- include/asm-ia64/semaphore.h | 100 +-------- include/asm-m32r/semaphore.h | 145 +------------ include/asm-m68k/semaphore-helper.h | 142 ------------- include/asm-m68k/semaphore.h | 164 +-------------- include/asm-m68knommu/semaphore-helper.h | 82 -------- include/asm-m68knommu/semaphore.h | 154 +------------- include/asm-mips/semaphore.h | 109 +--------- include/asm-mn10300/semaphore.h | 170 +-------------- include/asm-parisc/semaphore-helper.h | 89 -------- include/asm-parisc/semaphore.h | 146 +------------ include/asm-powerpc/semaphore.h | 95 +-------- include/asm-s390/semaphore.h | 108 +--------- include/asm-sh/semaphore-helper.h | 89 -------- include/asm-sh/semaphore.h | 116 +---------- include/asm-sparc/semaphore.h | 193 +---------------- include/asm-sparc64/semaphore.h | 54 +---- include/asm-um/semaphore.h | 7 +- include/asm-v850/semaphore.h | 85 +------- include/asm-x86/semaphore.h | 6 +- include/asm-x86/semaphore_32.h | 175 ---------------- include/asm-x86/semaphore_64.h | 180 ---------------- include/asm-xtensa/semaphore.h | 100 +-------- include/linux/semaphore.h | 77 +++++++ kernel/Makefile | 2 +- kernel/semaphore.c | 187 +++++++++++++++++ lib/Makefile | 1 - lib/semaphore-sleepers.c | 176 ---------------- 113 files changed, 314 insertions(+), 7679 deletions(-) delete mode 100644 arch/alpha/kernel/semaphore.c delete mode 100644 arch/arm/kernel/semaphore.c delete mode 100644 arch/avr32/kernel/semaphore.c delete mode 100644 arch/cris/kernel/semaphore.c delete mode 100644 arch/frv/kernel/semaphore.c delete mode 100644 arch/h8300/kernel/semaphore.c delete mode 100644 arch/ia64/kernel/semaphore.c delete mode 100644 arch/m32r/kernel/semaphore.c delete mode 100644 arch/m68k/kernel/semaphore.c delete mode 100644 arch/m68k/lib/semaphore.S delete mode 100644 arch/m68knommu/kernel/semaphore.c delete mode 100644 arch/m68knommu/lib/semaphore.S delete mode 100644 arch/mips/kernel/semaphore.c delete mode 100644 arch/mn10300/kernel/semaphore.c delete mode 100644 arch/parisc/kernel/semaphore.c delete mode 100644 arch/powerpc/kernel/semaphore.c delete mode 100644 arch/ppc/kernel/semaphore.c delete mode 100644 arch/s390/kernel/semaphore.c delete mode 100644 arch/sh/kernel/semaphore.c delete mode 100644 arch/sparc/kernel/semaphore.c delete mode 100644 arch/sparc64/kernel/semaphore.c delete mode 100644 arch/v850/kernel/semaphore.c delete mode 100644 arch/xtensa/kernel/semaphore.c delete mode 100644 include/asm-arm/semaphore-helper.h delete mode 100644 include/asm-blackfin/semaphore-helper.h delete mode 100644 include/asm-cris/semaphore-helper.h delete mode 100644 include/asm-h8300/semaphore-helper.h delete mode 100644 include/asm-m68k/semaphore-helper.h delete mode 100644 include/asm-m68knommu/semaphore-helper.h delete mode 100644 include/asm-parisc/semaphore-helper.h delete mode 100644 include/asm-sh/semaphore-helper.h delete mode 100644 include/asm-x86/semaphore_32.h delete mode 100644 include/asm-x86/semaphore_64.h create mode 100644 include/linux/semaphore.h create mode 100644 kernel/semaphore.c delete mode 100644 lib/semaphore-sleepers.c diff --git a/arch/alpha/kernel/Makefile b/arch/alpha/kernel/Makefile index dccf05245d..ac706c1d7a 100644 --- a/arch/alpha/kernel/Makefile +++ b/arch/alpha/kernel/Makefile @@ -7,7 +7,7 @@ EXTRA_AFLAGS := $(KBUILD_CFLAGS) EXTRA_CFLAGS := -Werror -Wno-sign-compare obj-y := entry.o traps.o process.o init_task.o osf_sys.o irq.o \ - irq_alpha.o signal.o setup.o ptrace.o time.o semaphore.o \ + irq_alpha.o signal.o setup.o ptrace.o time.o \ alpha_ksyms.o systbls.o err_common.o io.o obj-$(CONFIG_VGA_HOSE) += console.o diff --git a/arch/alpha/kernel/alpha_ksyms.c b/arch/alpha/kernel/alpha_ksyms.c index e9762a33b0..d96e742d4d 100644 --- a/arch/alpha/kernel/alpha_ksyms.c +++ b/arch/alpha/kernel/alpha_ksyms.c @@ -77,15 +77,6 @@ EXPORT_SYMBOL(__do_clear_user); EXPORT_SYMBOL(__strncpy_from_user); EXPORT_SYMBOL(__strnlen_user); -/* Semaphore helper functions. */ -EXPORT_SYMBOL(__down_failed); -EXPORT_SYMBOL(__down_failed_interruptible); -EXPORT_SYMBOL(__up_wakeup); -EXPORT_SYMBOL(down); -EXPORT_SYMBOL(down_interruptible); -EXPORT_SYMBOL(down_trylock); -EXPORT_SYMBOL(up); - /* * SMP-specific symbols. */ diff --git a/arch/alpha/kernel/semaphore.c b/arch/alpha/kernel/semaphore.c deleted file mode 100644 index 8d2982aa1b..0000000000 --- a/arch/alpha/kernel/semaphore.c +++ /dev/null @@ -1,224 +0,0 @@ -/* - * Alpha semaphore implementation. - * - * (C) Copyright 1996 Linus Torvalds - * (C) Copyright 1999, 2000 Richard Henderson - */ - -#include -#include -#include - -/* - * This is basically the PPC semaphore scheme ported to use - * the Alpha ll/sc sequences, so see the PPC code for - * credits. - */ - -/* - * Atomically update sem->count. - * This does the equivalent of the following: - * - * old_count = sem->count; - * tmp = MAX(old_count, 0) + incr; - * sem->count = tmp; - * return old_count; - */ -static inline int __sem_update_count(struct semaphore *sem, int incr) -{ - long old_count, tmp = 0; - - __asm__ __volatile__( - "1: ldl_l %0,%2\n" - " cmovgt %0,%0,%1\n" - " addl %1,%3,%1\n" - " stl_c %1,%2\n" - " beq %1,2f\n" - " mb\n" - ".subsection 2\n" - "2: br 1b\n" - ".previous" - : "=&r" (old_count), "=&r" (tmp), "=m" (sem->count) - : "Ir" (incr), "1" (tmp), "m" (sem->count)); - - return old_count; -} - -/* - * Perform the "down" function. Return zero for semaphore acquired, - * return negative for signalled out of the function. - * - * If called from down, the return is ignored and the wait loop is - * not interruptible. This means that a task waiting on a semaphore - * using "down()" cannot be killed until someone does an "up()" on - * the semaphore. - * - * If called from down_interruptible, the return value gets checked - * upon return. If the return value is negative then the task continues - * with the negative value in the return register (it can be tested by - * the caller). - * - * Either form may be used in conjunction with "up()". - */ - -void __sched -__down_failed(struct semaphore *sem) -{ - struct task_struct *tsk = current; - DECLARE_WAITQUEUE(wait, tsk); - -#ifdef CONFIG_DEBUG_SEMAPHORE - printk("%s(%d): down failed(%p)\n", - tsk->comm, task_pid_nr(tsk), sem); -#endif - - tsk->state = TASK_UNINTERRUPTIBLE; - wmb(); - add_wait_queue_exclusive(&sem->wait, &wait); - - /* - * Try to get the semaphore. If the count is > 0, then we've - * got the semaphore; we decrement count and exit the loop. - * If the count is 0 or negative, we set it to -1, indicating - * that we are asleep, and then sleep. - */ - while (__sem_update_count(sem, -1) <= 0) { - schedule(); - set_task_state(tsk, TASK_UNINTERRUPTIBLE); - } - remove_wait_queue(&sem->wait, &wait); - tsk->state = TASK_RUNNING; - - /* - * If there are any more sleepers, wake one of them up so - * that it can either get the semaphore, or set count to -1 - * indicating that there are still processes sleeping. - */ - wake_up(&sem->wait); - -#ifdef CONFIG_DEBUG_SEMAPHORE - printk("%s(%d): down acquired(%p)\n", - tsk->comm, task_pid_nr(tsk), sem); -#endif -} - -int __sched -__down_failed_interruptible(struct semaphore *sem) -{ - struct task_struct *tsk = current; - DECLARE_WAITQUEUE(wait, tsk); - long ret = 0; - -#ifdef CONFIG_DEBUG_SEMAPHORE - printk("%s(%d): down failed(%p)\n", - tsk->comm, task_pid_nr(tsk), sem); -#endif - - tsk->state = TASK_INTERRUPTIBLE; - wmb(); - add_wait_queue_exclusive(&sem->wait, &wait); - - while (__sem_update_count(sem, -1) <= 0) { - if (signal_pending(current)) { - /* - * A signal is pending - give up trying. - * Set sem->count to 0 if it is negative, - * since we are no longer sleeping. - */ - __sem_update_count(sem, 0); - ret = -EINTR; - break; - } - schedule(); - set_task_state(tsk, TASK_INTERRUPTIBLE); - } - - remove_wait_queue(&sem->wait, &wait); - tsk->state = TASK_RUNNING; - wake_up(&sem->wait); - -#ifdef CONFIG_DEBUG_SEMAPHORE - printk("%s(%d): down %s(%p)\n", - current->comm, task_pid_nr(current), - (ret < 0 ? "interrupted" : "acquired"), sem); -#endif - return ret; -} - -void -__up_wakeup(struct semaphore *sem) -{ - /* - * Note that we incremented count in up() before we came here, - * but that was ineffective since the result was <= 0, and - * any negative value of count is equivalent to 0. - * This ends up setting count to 1, unless count is now > 0 - * (i.e. because some other cpu has called up() in the meantime), - * in which case we just increment count. - */ - __sem_update_count(sem, 1); - wake_up(&sem->wait); -} - -void __sched -down(struct semaphore *sem) -{ -#ifdef WAITQUEUE_DEBUG - CHECK_MAGIC(sem->__magic); -#endif -#ifdef CONFIG_DEBUG_SEMAPHORE - printk("%s(%d): down(%p) from %p\n", - current->comm, task_pid_nr(current), sem, - atomic_read(&sem->count), __builtin_return_address(0)); -#endif - __down(sem); -} - -int __sched -down_interruptible(struct semaphore *sem) -{ -#ifdef WAITQUEUE_DEBUG - CHECK_MAGIC(sem->__magic); -#endif -#ifdef CONFIG_DEBUG_SEMAPHORE - printk("%s(%d): down(%p) from %p\n", - current->comm, task_pid_nr(current), sem, - atomic_read(&sem->count), __builtin_return_address(0)); -#endif - return __down_interruptible(sem); -} - -int -down_trylock(struct semaphore *sem) -{ - int ret; - -#ifdef WAITQUEUE_DEBUG - CHECK_MAGIC(sem->__magic); -#endif - - ret = __down_trylock(sem); - -#ifdef CONFIG_DEBUG_SEMAPHORE - printk("%s(%d): down_trylock %s from %p\n", - current->comm, task_pid_nr(current), - ret ? "failed" : "acquired", - __builtin_return_address(0)); -#endif - - return ret; -} - -void -up(struct semaphore *sem) -{ -#ifdef WAITQUEUE_DEBUG - CHECK_MAGIC(sem->__magic); -#endif -#ifdef CONFIG_DEBUG_SEMAPHORE - printk("%s(%d): up(%p) from %p\n", - current->comm, task_pid_nr(current), sem, - atomic_read(&sem->count), __builtin_return_address(0)); -#endif - __up(sem); -} diff --git a/arch/arm/kernel/Makefile b/arch/arm/kernel/Makefile index 00d44c6fbf..6235f72a14 100644 --- a/arch/arm/kernel/Makefile +++ b/arch/arm/kernel/Makefile @@ -7,7 +7,7 @@ AFLAGS_head.o := -DTEXT_OFFSET=$(TEXT_OFFSET) # Object file lists. obj-y := compat.o entry-armv.o entry-common.o irq.o \ - process.o ptrace.o semaphore.o setup.o signal.o \ + process.o ptrace.o setup.o signal.o \ sys_arm.o stacktrace.o time.o traps.o obj-$(CONFIG_ISA_DMA_API) += dma.o diff --git a/arch/arm/kernel/semaphore.c b/arch/arm/kernel/semaphore.c deleted file mode 100644 index 981fe5c6cc..0000000000 --- a/arch/arm/kernel/semaphore.c +++ /dev/null @@ -1,221 +0,0 @@ -/* - * ARM semaphore implementation, taken from - * - * i386 semaphore implementation. - * - * (C) Copyright 1999 Linus Torvalds - * - * Modified for ARM by Russell King - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License version 2 as - * published by the Free Software Foundation. - */ -#include -#include -#include -#include - -#include - -/* - * Semaphores are implemented using a two-way counter: - * The "count" variable is decremented for each process - * that tries to acquire the semaphore, while the "sleeping" - * variable is a count of such acquires. - * - * Notably, the inline "up()" and "down()" functions can - * efficiently test if they need to do any extra work (up - * needs to do something only if count was negative before - * the increment operation. - * - * "sleeping" and the contention routine ordering is - * protected by the semaphore spinlock. - * - * Note that these functions are only called when there is - * contention on the lock, and as such all this is the - * "non-critical" part of the whole semaphore business. The - * critical part is the inline stuff in - * where we want to avoid any extra jumps and calls. - */ - -/* - * Logic: - * - only on a boundary condition do we need to care. When we go - * from a negative count to a non-negative, we wake people up. - * - when we go from a non-negative count to a negative do we - * (a) synchronize with the "sleeper" count and (b) make sure - * that we're on the wakeup list before we synchronize so that - * we cannot lose wakeup events. - */ - -void __up(struct semaphore *sem) -{ - wake_up(&sem->wait); -} - -static DEFINE_SPINLOCK(semaphore_lock); - -void __sched __down(struct semaphore * sem) -{ - struct task_struct *tsk = current; - DECLARE_WAITQUEUE(wait, tsk); - tsk->state = TASK_UNINTERRUPTIBLE; - add_wait_queue_exclusive(&sem->wait, &wait); - - spin_lock_irq(&semaphore_lock); - sem->sleepers++; - for (;;) { - int sleepers = sem->sleepers; - - /* - * Add "everybody else" into it. They aren't - * playing, because we own the spinlock. - */ - if (!atomic_add_negative(sleepers - 1, &sem->count)) { - sem->sleepers = 0; - break; - } - sem->sleepers = 1; /* us - see -1 above */ - spin_unlock_irq(&semaphore_lock); - - schedule(); - tsk->state = TASK_UNINTERRUPTIBLE; - spin_lock_irq(&semaphore_lock); - } - spin_unlock_irq(&semaphore_lock); - remove_wait_queue(&sem->wait, &wait); - tsk->state = TASK_RUNNING; - wake_up(&sem->wait); -} - -int __sched __down_interruptible(struct semaphore * sem) -{ - int retval = 0; - struct task_struct *tsk = current; - DECLARE_WAITQUEUE(wait, tsk); - tsk->state = TASK_INTERRUPTIBLE; - add_wait_queue_exclusive(&sem->wait, &wait); - - spin_lock_irq(&semaphore_lock); - sem->sleepers ++; - for (;;) { - int sleepers = sem->sleepers; - - /* - * With signals pending, this turns into - * the trylock failure case - we won't be - * sleeping, and we* can't get the lock as - * it has contention. Just correct the count - * and exit. - */ - if (signal_pending(current)) { - retval = -EINTR; - sem->sleepers = 0; - atomic_add(sleepers, &sem->count); - break; - } - - /* - * Add "everybody else" into it. They aren't - * playing, because we own the spinlock. The - * "-1" is because we're still hoping to get - * the lock. - */ - if (!atomic_add_negative(sleepers - 1, &sem->count)) { - sem->sleepers = 0; - break; - } - sem->sleepers = 1; /* us - see -1 above */ - spin_unlock_irq(&semaphore_lock); - - schedule(); - tsk->state = TASK_INTERRUPTIBLE; - spin_lock_irq(&semaphore_lock); - } - spin_unlock_irq(&semaphore_lock); - tsk->state = TASK_RUNNING; - remove_wait_queue(&sem->wait, &wait); - wake_up(&sem->wait); - return retval; -} - -/* - * Trylock failed - make sure we correct for - * having decremented the count. - * - * We could have done the trylock with a - * single "cmpxchg" without failure cases, - * but then it wouldn't work on a 386. - */ -int __down_trylock(struct semaphore * sem) -{ - int sleepers; - unsigned long flags; - - spin_lock_irqsave(&semaphore_lock, flags); - sleepers = sem->sleepers + 1; - sem->sleepers = 0; - - /* - * Add "everybody else" and us into it. They aren't - * playing, because we own the spinlock. - */ - if (!atomic_add_negative(sleepers, &sem->count)) - wake_up(&sem->wait); - - spin_unlock_irqrestore(&semaphore_lock, flags); - return 1; -} - -/* - * The semaphore operations have a special calling sequence that - * allow us to do a simpler in-line version of them. These routines - * need to convert that sequence back into the C sequence when - * there is contention on the semaphore. - * - * ip contains the semaphore pointer on entry. Save the C-clobbered - * registers (r0 to r3 and lr), but not ip, as we use it as a return - * value in some cases.. - * To remain AAPCS compliant (64-bit stack align) we save r4 as well. - */ -asm(" .section .sched.text,\"ax\",%progbits \n\ - .align 5 \n\ - .globl __down_failed \n\ -__down_failed: \n\ - stmfd sp!, {r0 - r4, lr} \n\ - mov r0, ip \n\ - bl __down \n\ - ldmfd sp!, {r0 - r4, pc} \n\ - \n\ - .align 5 \n\ - .globl __down_interruptible_failed \n\ -__down_interruptible_failed: \n\ - stmfd sp!, {r0 - r4, lr} \n\ - mov r0, ip \n\ - bl __down_interruptible \n\ - mov ip, r0 \n\ - ldmfd sp!, {r0 - r4, pc} \n\ - \n\ - .align 5 \n\ - .globl __down_trylock_failed \n\ -__down_trylock_failed: \n\ - stmfd sp!, {r0 - r4, lr} \n\ - mov r0, ip \n\ - bl __down_trylock \n\ - mov ip, r0 \n\ - ldmfd sp!, {r0 - r4, pc} \n\ - \n\ - .align 5 \n\ - .globl __up_wakeup \n\ -__up_wakeup: \n\ - stmfd sp!, {r0 - r4, lr} \n\ - mov r0, ip \n\ - bl __up \n\ - ldmfd sp!, {r0 - r4, pc} \n\ - "); - -EXPORT_SYMBOL(__down_failed); -EXPORT_SYMBOL(__down_interruptible_failed); -EXPORT_SYMBOL(__down_trylock_failed); -EXPORT_SYMBOL(__up_wakeup); diff --git a/arch/avr32/kernel/Makefile b/arch/avr32/kernel/Makefile index e4b6d122b0..18229d0d18 100644 --- a/arch/avr32/kernel/Makefile +++ b/arch/avr32/kernel/Makefile @@ -6,7 +6,7 @@ extra-y := head.o vmlinux.lds obj-$(CONFIG_SUBARCH_AVR32B) += entry-avr32b.o obj-y += syscall_table.o syscall-stubs.o irq.o -obj-y += setup.o traps.o semaphore.o ocd.o ptrace.o +obj-y += setup.o traps.o ocd.o ptrace.o obj-y += signal.o sys_avr32.o process.o time.o obj-y += init_task.o switch_to.o cpu.o obj-$(CONFIG_MODULES) += module.o avr32_ksyms.o diff --git a/arch/avr32/kernel/semaphore.c b/arch/avr32/kernel/semaphore.c deleted file mode 100644 index 1e2705a050..0000000000 --- a/arch/avr32/kernel/semaphore.c +++ /dev/null @@ -1,148 +0,0 @@ -/* - * AVR32 sempahore implementation. - * - * Copyright (C) 2004-2006 Atmel Corporation - * - * Based on linux/arch/i386/kernel/semaphore.c - * Copyright (C) 1999 Linus Torvalds - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License version 2 as - * published by the Free Software Foundation. - */ - -#include -#include -#include - -#include -#include - -/* - * Semaphores are implemented using a two-way counter: - * The "count" variable is decremented for each process - * that tries to acquire the semaphore, while the "sleeping" - * variable is a count of such acquires. - * - * Notably, the inline "up()" and "down()" functions can - * efficiently test if they need to do any extra work (up - * needs to do something only if count was negative before - * the increment operation. - * - * "sleeping" and the contention routine ordering is protected - * by the spinlock in the semaphore's waitqueue head. - * - * Note that these functions are only called when there is - * contention on the lock, and as such all this is the - * "non-critical" part of the whole semaphore business. The - * critical part is the inline stuff in - * where we want to avoid any extra jumps and calls. - */ - -/* - * Logic: - * - only on a boundary condition do we need to care. When we go - * from a negative count to a non-negative, we wake people up. - * - when we go from a non-negative count to a negative do we - * (a) synchronize with the "sleeper" count and (b) make sure - * that we're on the wakeup list before we synchronize so that - * we cannot lose wakeup events. - */ - -void __up(struct semaphore *sem) -{ - wake_up(&sem->wait); -} -EXPORT_SYMBOL(__up); - -void __sched __down(struct semaphore *sem) -{ - struct task_struct *tsk = current; - DECLARE_WAITQUEUE(wait, tsk); - unsigned long flags; - - tsk->state = TASK_UNINTERRUPTIBLE; - spin_lock_irqsave(&sem->wait.lock, flags); - add_wait_queue_exclusive_locked(&sem->wait, &wait); - - sem->sleepers++; - for (;;) { - int sleepers = sem->sleepers; - - /* - * Add "everybody else" into it. They aren't - * playing, because we own the spinlock in - * the wait_queue_head. - */ - if (atomic_add_return(sleepers - 1, &sem->count) >= 0) { - sem->sleepers = 0; - break; - } - sem->sleepers = 1; /* us - see -1 above */ - spin_unlock_irqrestore(&sem->wait.lock, flags); - - schedule(); - - spin_lock_irqsave(&sem->wait.lock, flags); - tsk->state = TASK_UNINTERRUPTIBLE; - } - remove_wait_queue_locked(&sem->wait, &wait); - wake_up_locked(&sem->wait); - spin_unlock_irqrestore(&sem->wait.lock, flags); - tsk->state = TASK_RUNNING; -} -EXPORT_SYMBOL(__down); - -int __sched __down_interruptible(struct semaphore *sem) -{ - int retval = 0; - struct task_struct *tsk = current; - DECLARE_WAITQUEUE(wait, tsk); - unsigned long flags; - - tsk->state = TASK_INTERRUPTIBLE; - spin_lock_irqsave(&sem->wait.lock, flags); - add_wait_queue_exclusive_locked(&sem->wait, &wait); - - sem->sleepers++; - for (;;) { - int sleepers = sem->sleepers; - - /* - * With signals pending, this turns into the trylock - * failure case - we won't be sleeping, and we can't - * get the lock as it has contention. Just correct the - * count and exit. - */ - if (signal_pending(current)) { - retval = -EINTR; - sem->sleepers = 0; - atomic_add(sleepers, &sem->count); - break; - } - - /* - * Add "everybody else" into it. They aren't - * playing, because we own the spinlock in - * the wait_queue_head. - */ - if (atomic_add_return(sleepers - 1, &sem->count) >= 0) { - sem->sleepers = 0; - break; - } - sem->sleepers = 1; /* us - see -1 above */ - spin_unlock_irqrestore(&sem->wait.lock, flags); - - schedule(); - - spin_lock_irqsave(&sem->wait.lock, flags); - tsk->state = TASK_INTERRUPTIBLE; - } - remove_wait_queue_locked(&sem->wait, &wait); - wake_up_locked(&sem->wait); - spin_unlock_irqrestore(&sem->wait.lock, flags); - - tsk->state = TASK_RUNNING; - return retval; -} -EXPORT_SYMBOL(__down_interruptible); diff --git a/arch/blackfin/Kconfig b/arch/blackfin/Kconfig index 589c6aca48..2dd1f300a5 100644 --- a/arch/blackfin/Kconfig +++ b/arch/blackfin/Kconfig @@ -31,10 +31,6 @@ config ZONE_DMA bool default y -config SEMAPHORE_SLEEPERS - bool - default y - config GENERIC_FIND_NEXT_BIT bool default y diff --git a/arch/blackfin/kernel/bfin_ksyms.c b/arch/blackfin/kernel/bfin_ksyms.c index 0bfbb269e3..053edff6c0 100644 --- a/arch/blackfin/kernel/bfin_ksyms.c +++ b/arch/blackfin/kernel/bfin_ksyms.c @@ -42,11 +42,6 @@ EXPORT_SYMBOL(ip_fast_csum); EXPORT_SYMBOL(kernel_thread); -EXPORT_SYMBOL(__up); -EXPORT_SYMBOL(__down); -EXPORT_SYMBOL(__down_trylock); -EXPORT_SYMBOL(__down_interruptible); - EXPORT_SYMBOL(is_in_rom); EXPORT_SYMBOL(bfin_return_from_exception); diff --git a/arch/cris/kernel/Makefile b/arch/cris/kernel/Makefile index c8e8ea5709..ee7bcd4d20 100644 --- a/arch/cris/kernel/Makefile +++ b/arch/cris/kernel/Makefile @@ -5,8 +5,7 @@ extra-y := vmlinux.lds -obj-y := process.o traps.o irq.o ptrace.o setup.o \ - time.o sys_cris.o semaphore.o +obj-y := process.o traps.o irq.o ptrace.o setup.o time.o sys_cris.o obj-$(CONFIG_MODULES) += crisksyms.o obj-$(CONFIG_MODULES) += module.o diff --git a/arch/cris/kernel/crisksyms.c b/arch/cris/kernel/crisksyms.c index 62f0e75291..7ac000f6a8 100644 --- a/arch/cris/kernel/crisksyms.c +++ b/arch/cris/kernel/crisksyms.c @@ -9,7 +9,6 @@ #include #include -#include #include #include #include @@ -49,12 +48,6 @@ EXPORT_SYMBOL(__negdi2); EXPORT_SYMBOL(__ioremap); EXPORT_SYMBOL(iounmap); -/* Semaphore functions */ -EXPORT_SYMBOL(__up); -EXPORT_SYMBOL(__down); -EXPORT_SYMBOL(__down_interruptible); -EXPORT_SYMBOL(__down_trylock); - /* Userspace access functions */ EXPORT_SYMBOL(__copy_user_zeroing); EXPORT_SYMBOL(__copy_user); diff --git a/arch/cris/kernel/semaphore.c b/arch/cris/kernel/semaphore.c deleted file mode 100644 index f137a43904..0000000000 --- a/arch/cris/kernel/semaphore.c +++ /dev/null @@ -1,129 +0,0 @@ -/* - * Generic semaphore code. Buyer beware. Do your own - * specific changes in - */ - -#include -#include - -/* - * Semaphores are implemented using a two-way counter: - * The "count" variable is decremented for each process - * that tries to sleep, while the "waking" variable is - * incremented when the "up()" code goes to wake up waiting - * processes. - * - * Notably, the inline "up()" and "down()" functions can - * efficiently test if they need to do any extra work (up - * needs to do something only if count was negative before - * the increment operation. - * - * waking_non_zero() (from asm/semaphore.h) must execute - * atomically. - * - * When __up() is called, the count was negative before - * incrementing it, and we need to wake up somebody. - * - * This routine adds one to the count of processes that need to - * wake up and exit. ALL waiting processes actually wake up but - * only the one that gets to the "waking" field first will gate - * through and acquire the semaphore. The others will go back - * to sleep. - * - * Note that these functions are only called when there is - * contention on the lock, and as such all this is the - * "non-critical" part of the whole semaphore business. The - * critical part is the inline stuff in - * where we want to avoid any extra jumps and calls. - */ -void __up(struct semaphore *sem) -{ - wake_one_more(sem); - wake_up(&sem->wait); -} - -/* - * Perform the "down" function. Return zero for semaphore acquired, - * return negative for signalled out of the function. - * - * If called from __down, the return is ignored and the wait loop is - * not interruptible. This means that a task waiting on a semaphore - * using "down()" cannot be killed until someone does an "up()" on - * the semaphore. - * - * If called from __down_interruptible, the return value gets checked - * upon return. If the return value is negative then the task continues - * with the negative value in the return register (it can be tested by - * the caller). - * - * Either form may be used in conjunction with "up()". - * - */ - -#define DOWN_VAR \ - struct task_struct *tsk = current; \ - wait_queue_t wait; \ - init_waitqueue_entry(&wait, tsk); - -#define DOWN_HEAD(task_state) \ - \ - \ - tsk->state = (task_state); \ - add_wait_queue(&sem->wait, &wait); \ - \ - /* \ - * Ok, we're set up. sem->count is known to be less than zero \ - * so we must wait. \ - * \ - * We can let go the lock for purposes of waiting. \ - * We re-acquire it after awaking so as to protect \ - * all semaphore operations. \ - * \ - * If "up()" is called before we call waking_non_zero() then \ - * we will catch it right away. If it is called later then \ - * we will have to go through a wakeup cycle to catch it. \ - * \ - * Multiple waiters contend for the semaphore lock to see \ - * who gets to gate through and who has to wait some more. \ - */ \ - for (;;) { - -#define DOWN_TAIL(task_state) \ - tsk->state = (task_state); \ - } \ - tsk->state = TASK_RUNNING; \ - remove_wait_queue(&sem->wait, &wait); - -void __sched __down(struct semaphore * sem) -{ - DOWN_VAR - DOWN_HEAD(TASK_UNINTERRUPTIBLE) - if (waking_non_zero(sem)) - break; - schedule(); - DOWN_TAIL(TASK_UNINTERRUPTIBLE) -} - -int __sched __down_interruptible(struct semaphore * sem) -{ - int ret = 0; - DOWN_VAR - DOWN_HEAD(TASK_INTERRUPTIBLE) - - ret = waking_non_zero_interruptible(sem, tsk); - if (ret) - { - if (ret == 1) - /* ret != 0 only if we get interrupted -arca */ - ret = 0; - break; - } - schedule(); - DOWN_TAIL(TASK_INTERRUPTIBLE) - return ret; -} - -int __down_trylock(struct semaphore * sem) -{ - return waking_non_zero_trylock(sem); -} diff --git a/arch/frv/kernel/Makefile b/arch/frv/kernel/Makefile index e8f73ed28b..c36f70b669 100644 --- a/arch/frv/kernel/Makefile +++ b/arch/frv/kernel/Makefile @@ -9,7 +9,7 @@ extra-y:= head.o init_task.o vmlinux.lds obj-y := $(heads-y) entry.o entry-table.o break.o switch_to.o kernel_thread.o \ kernel_execve.o process.o traps.o ptrace.o signal.o dma.o \ - sys_frv.o time.o semaphore.o setup.o frv_ksyms.o \ + sys_frv.o time.o setup.o frv_ksyms.o \ debug-stub.o irq.o sleep.o uaccess.o obj-$(CONFIG_GDBSTUB) += gdb-stub.o gdb-io.o diff --git a/arch/frv/kernel/frv_ksyms.c b/arch/frv/kernel/frv_ksyms.c index f772704b3d..0316b3c50e 100644 --- a/arch/frv/kernel/frv_ksyms.c +++ b/arch/frv/kernel/frv_ksyms.c @@ -12,7 +12,6 @@ #include #include #include -#include #include #include #include diff --git a/arch/frv/kernel/semaphore.c b/arch/frv/kernel/semaphore.c deleted file mode 100644 index 7ee3a147b4..0000000000 --- a/arch/frv/kernel/semaphore.c +++ /dev/null @@ -1,155 +0,0 @@ -/* semaphore.c: FR-V semaphores - * - * Copyright (C) 2003 Red Hat, Inc. All Rights Reserved. - * Written by David Howells (dhowells@redhat.com) - * - Derived from lib/rwsem-spinlock.c - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public License - * as published by the Free Software Foundation; either version - * 2 of the License, or (at your option) any later version. - */ - -#include -#include -#include - -struct sem_waiter { - struct list_head list; - struct task_struct *task; -}; - -#ifdef CONFIG_DEBUG_SEMAPHORE -void semtrace(struct semaphore *sem, const char *str) -{ - if (sem->debug) - printk("[%d] %s({%d,%d})\n", - current->pid, - str, - sem->counter, - list_empty(&sem->wait_list) ? 0 : 1); -} -#else -#define semtrace(SEM,STR) do { } while(0) -#endif - -/* - * wait for a token to be granted from a semaphore - * - entered with lock held and interrupts disabled - */ -void __down(struct semaphore *sem, unsigned long flags) -{ - struct task_struct *tsk = current; - struct sem_waiter waiter; - - semtrace(sem, "Entering __down"); - - /* set up my own style of waitqueue */ - waiter.task = tsk; - get_task_struct(tsk); - - list_add_tail(&waiter.list, &sem->wait_list); - - /* we don't need to touch the semaphore struct anymore */ - spin_unlock_irqrestore(&sem->wait_lock, flags); - - /* wait to be given the semaphore */ - set_task_state(tsk, TASK_UNINTERRUPTIBLE); - - for (;;) { - if (list_empty(&waiter.list)) - break; - schedule(); - set_task_state(tsk, TASK_UNINTERRUPTIBLE); - } - - tsk->state = TASK_RUNNING; - semtrace(sem, "Leaving __down"); -} - -EXPORT_SYMBOL(__down); - -/* - * interruptibly wait for a token to be granted from a semaphore - * - entered with lock held and interrupts disabled - */ -int __down_interruptible(struct semaphore *sem, unsigned long flags) -{ - struct task_struct *tsk = current; - struct sem_waiter waiter; - int ret; - - semtrace(sem,"Entering __down_interruptible"); - - /* set up my own style of waitqueue */ - waiter.task = tsk; - get_task_struct(tsk); - - list_add_tail(&waiter.list, &sem->wait_list); - - /* we don't need to touch the semaphore struct anymore */ - set_task_state(tsk, TASK_INTERRUPTIBLE); - - spin_unlock_irqrestore(&sem->wait_lock, flags); - - /* wait to be given the semaphore */ - ret = 0; - for (;;) { - if (list_empty(&waiter.list)) - break; - if (unlikely(signal_pending(current))) - goto interrupted; - schedule(); - set_task_state(tsk, TASK_INTERRUPTIBLE); - } - - out: - tsk->state = TASK_RUNNING; - semtrace(sem, "Leaving __down_interruptible"); - return ret; - - interrupted: - spin_lock_irqsave(&sem->wait_lock, flags); - - if (!list_empty(&waiter.list)) { - list_del(&waiter.list); - ret = -EINTR; - } - - spin_unlock_irqrestore(&sem->wait_lock, flags); - if (ret == -EINTR) - put_task_struct(current); - goto out; -} - -EXPORT_SYMBOL(__down_interruptible); - -/* - * release a single token back to a semaphore - * - entered with lock held and interrupts disabled - */ -void __up(struct semaphore *sem) -{ - struct task_struct *tsk; - struct sem_waiter *waiter; - - semtrace(sem,"Entering __up"); - - /* grant the token to the process at the front of the queue */ - waiter = list_entry(sem->wait_list.next, struct sem_waiter, list); - - /* We must be careful not to touch 'waiter' after we set ->task = NULL. - * It is allocated on the waiter's stack and may become invalid at - * any time after that point (due to a wakeup from another source). - */ - list_del_init(&waiter->list); - tsk = waiter->task; - mb(); - waiter->task = NULL; - wake_up_process(tsk); - put_task_struct(tsk); - - semtrace(sem,"Leaving __up"); -} - -EXPORT_SYMBOL(__up); diff --git a/arch/h8300/kernel/Makefile b/arch/h8300/kernel/Makefile index 874f6aefee..6c248c3c5c 100644 --- a/arch/h8300/kernel/Makefile +++ b/arch/h8300/kernel/Makefile @@ -5,7 +5,7 @@ extra-y := vmlinux.lds obj-y := process.o traps.o ptrace.o irq.o \ - sys_h8300.o time.o semaphore.o signal.o \ + sys_h8300.o time.o signal.o \ setup.o gpio.o init_task.o syscalls.o \ entry.o diff --git a/arch/h8300/kernel/h8300_ksyms.c b/arch/h8300/kernel/h8300_ksyms.c index d1b15267ac..6866bd9c7f 100644 --- a/arch/h8300/kernel/h8300_ksyms.c +++ b/arch/h8300/kernel/h8300_ksyms.c @@ -12,7 +12,6 @@ #include #include #include -#include #include #include #include diff --git a/arch/h8300/kernel/semaphore.c b/arch/h8300/kernel/semaphore.c deleted file mode 100644 index d12cbbfe6e..0000000000 --- a/arch/h8300/kernel/semaphore.c +++ /dev/null @@ -1,132 +0,0 @@ -/* - * Generic semaphore code. Buyer beware. Do your own - * specific changes in - */ - -#include -#include -#include - -#ifndef CONFIG_RMW_INSNS -spinlock_t semaphore_wake_lock; -#endif - -/* - * Semaphores are implemented using a two-way counter: - * The "count" variable is decremented for each process - * that tries to sleep, while the "waking" variable is - * incremented when the "up()" code goes to wake up waiting - * processes. - * - * Notably, the inline "up()" and "down()" functions can - * efficiently test if they need to do any extra work (up - * needs to do something only if count was negative before - * the increment operation. - * - * waking_non_zero() (from asm/semaphore.h) must execute - * atomically. - * - * When __up() is called, the count was negative before - * incrementing it, and we need to wake up somebody. - * - * This routine adds one to the count of processes that need to - * wake up and exit. ALL waiting processes actually wake up but - * only the one that gets to the "waking" field first will gate - * through and acquire the semaphore. The others will go back - * to sleep. - * - * Note that these functions are only called when there is - * contention on the lock, and as such all this is the - * "non-critical" part of the whole semaphore business. The - * critical part is the inline stuff in - * where we want to avoid any extra jumps and calls. - */ -void __up(struct semaphore *sem) -{ - wake_one_more(sem); - wake_up(&sem->wait); -} - -/* - * Perform the "down" function. Return zero for semaphore acquired, - * return negative for signalled out of the function. - * - * If called from __down, the return is ignored and the wait loop is - * not interruptible. This means that a task waiting on a semaphore - * using "down()" cannot be killed until someone does an "up()" on - * the semaphore. - * - * If called from __down_interruptible, the return value gets checked - * upon return. If the return value is negative then the task continues - * with the negative value in the return register (it can be tested by - * the caller). - * - * Either form may be used in conjunction with "up()". - * - */ - - -#define DOWN_HEAD(task_state) \ - \ - \ - current->state = (task_state); \ - add_wait_queue(&sem->wait, &wait); \ - \ - /* \ - * Ok, we're set up. sem->count is known to be less than zero \ - * so we must wait. \ - * \ - * We can let go the lock for purposes of waiting. \ - * We re-acquire it after awaking so as to protect \ - * all semaphore operations. \ - * \ - * If "up()" is called before we call waking_non_zero() then \ - * we will catch it right away. If it is called later then \ - * we will have to go through a wakeup cycle to catch it. \ - * \ - * Multiple waiters contend for the semaphore lock to see \ - * who gets to gate through and who has to wait some more. \ - */ \ - for (;;) { - -#define DOWN_TAIL(task_state) \ - current->state = (task_state); \ - } \ - current->state = TASK_RUNNING; \ - remove_wait_queue(&sem->wait, &wait); - -void __sched __down(struct semaphore * sem) -{ - DECLARE_WAITQUEUE(wait, current); - - DOWN_HEAD(TASK_UNINTERRUPTIBLE) - if (waking_non_zero(sem)) - break; - schedule(); - DOWN_TAIL(TASK_UNINTERRUPTIBLE) -} - -int __sched __down_interruptible(struct semaphore * sem) -{ - DECLARE_WAITQUEUE(wait, current); - int ret = 0; - - DOWN_HEAD(TASK_INTERRUPTIBLE) - - ret = waking_non_zero_interruptible(sem, current); - if (ret) - { - if (ret == 1) - /* ret != 0 only if we get interrupted -arca */ - ret = 0; - break; - } - schedule(); - DOWN_TAIL(TASK_INTERRUPTIBLE) - return ret; -} - -int __down_trylock(struct semaphore * sem) -{ - return waking_non_zero_trylock(sem); -} diff --git a/arch/ia64/kernel/Makefile b/arch/ia64/kernel/Makefile index 33e5a59867..13fd10e869 100644 --- a/arch/ia64/kernel/Makefile +++ b/arch/ia64/kernel/Makefile @@ -6,7 +6,7 @@ extra-y := head.o init_task.o vmlinux.lds obj-y := acpi.o entry.o efi.o efi_stub.o gate-data.o fsys.o ia64_ksyms.o irq.o irq_ia64.o \ irq_lsapic.o ivt.o machvec.o pal.o patch.o process.o perfmon.o ptrace.o sal.o \ - salinfo.o semaphore.o setup.o signal.o sys_ia64.o time.o traps.o unaligned.o \ + salinfo.o setup.o signal.o sys_ia64.o time.o traps.o unaligned.o \ unwind.o mca.o mca_asm.o topology.o obj-$(CONFIG_IA64_BRL_EMU) += brl_emu.o diff --git a/arch/ia64/kernel/ia64_ksyms.c b/arch/ia64/kernel/ia64_ksyms.c index 8e7193d555..6da1f20d73 100644 --- a/arch/ia64/kernel/ia64_ksyms.c +++ b/arch/ia64/kernel/ia64_ksyms.c @@ -19,12 +19,6 @@ EXPORT_SYMBOL_GPL(empty_zero_page); EXPORT_SYMBOL(ip_fast_csum); /* hand-coded assembly */ EXPORT_SYMBOL(csum_ipv6_magic); -#include -EXPORT_SYMBOL(__down); -EXPORT_SYMBOL(__down_interruptible); -EXPORT_SYMBOL(__down_trylock); -EXPORT_SYMBOL(__up); - #include EXPORT_SYMBOL(clear_page); diff --git a/arch/ia64/kernel/semaphore.c b/arch/ia64/kernel/semaphore.c deleted file mode 100644 index 2724ef3fba..0000000000 --- a/arch/ia64/kernel/semaphore.c +++ /dev/null @@ -1,165 +0,0 @@ -/* - * IA-64 semaphore implementation (derived from x86 version). - * - * Copyright (C) 1999-2000, 2002 Hewlett-Packard Co - * David Mosberger-Tang - */ - -/* - * Semaphores are implemented using a two-way counter: The "count" - * variable is decremented for each process that tries to acquire the - * semaphore, while the "sleepers" variable is a count of such - * acquires. - * - * Notably, the inline "up()" and "down()" functions can efficiently - * test if they need to do any extra work (up needs to do something - * only if count was negative before the increment operation. - * - * "sleeping" and the contention routine ordering is protected - * by the spinlock in the semaphore's waitqueue head. - * - * Note that these functions are only called when there is contention - * on the lock, and as such all this is the "non-critical" part of the - * whole semaphore business. The critical part is the inline stuff in - * where we want to avoid any extra jumps and calls. - */ -#include -#include - -#include -#include - -/* - * Logic: - * - Only on a boundary condition do we need to care. When we go - * from a negative count to a non-negative, we wake people up. - * - When we go from a non-negative count to a negative do we - * (a) synchronize with the "sleepers" count and (b) make sure - * that we're on the wakeup list before we synchronize so that - * we cannot lose wakeup events. - */ - -void -__up (struct semaphore *sem) -{ - wake_up(&sem->wait); -} - -void __sched __down (struct semaphore *sem) -{ - struct task_struct *tsk = current; - DECLARE_WAITQUEUE(wait, tsk); - unsigned long flags; - - tsk->state = TASK_UNINTERRUPTIBLE; - spin_lock_irqsave(&sem->wait.lock, flags); - add_wait_queue_exclusive_locked(&sem->wait, &wait); - - sem->sleepers++; - for (;;) { - int sleepers = sem->sleepers; - - /* - * Add "everybody else" into it. They aren't - * playing, because we own the spinlock in - * the wait_queue_head. - */ - if (!atomic_add_negative(sleepers - 1, &sem->count)) { - sem->sleepers = 0; - break; - } - sem->sleepers = 1; /* us - see -1 above */ - spin_unlock_irqrestore(&sem->wait.lock, flags); - - schedule(); - - spin_lock_irqsave(&sem->wait.lock, flags); - tsk->state = TASK_UNINTERRUPTIBLE; - } - remove_wait_queue_locked(&sem->wait, &wait); - wake_up_locked(&sem->wait); - spin_unlock_irqrestore(&sem->wait.lock, flags); - tsk->state = TASK_RUNNING; -} - -int __sched __down_interruptible (struct semaphore * sem) -{ - int retval = 0; - struct task_struct *tsk = current; - DECLARE_WAITQUEUE(wait, tsk); - unsigned long flags; - - tsk->state = TASK_INTERRUPTIBLE; - spin_lock_irqsave(&sem->wait.lock, flags); - add_wait_queue_exclusive_locked(&sem->wait, &wait); - - sem->sleepers ++; - for (;;) { - int sleepers = sem->sleepers; - - /* - * With signals pending, this turns into - * the trylock failure case - we won't be - * sleeping, and we* can't get the lock as - * it has contention. Just correct the count - * and exit. - */ - if (signal_pending(current)) { - retval = -EINTR; - sem->sleepers = 0; - atomic_add(sleepers, &sem->count); - break; - } - - /* - * Add "everybody else" into it. They aren't - * playing, because we own the spinlock in - * wait_queue_head. The "-1" is because we're - * still hoping to get the semaphore. - */ - if (!atomic_add_negative(sleepers - 1, &sem->count)) { - sem->sleepers = 0; - break; - } - sem->sleepers = 1; /* us - see -1 above */ - spin_unlock_irqrestore(&sem->wait.lock, flags); - - schedule(); - - spin_lock_irqsave(&sem->wait.lock, flags); - tsk->state = TASK_INTERRUPTIBLE; - } - remove_wait_queue_locked(&sem->wait, &wait); - wake_up_locked(&sem->wait); - spin_unlock_irqrestore(&sem->wait.lock, flags); - - tsk->state = TASK_RUNNING; - return retval; -} - -/* - * Trylock failed - make sure we correct for having decremented the - * count. - */ -int -__down_trylock (struct semaphore *sem) -{ - unsigned long flags; - int sleepers; - - spin_lock_irqsave(&sem->wait.lock, flags); - sleepers = sem->sleepers + 1; - sem->sleepers = 0; - - /* - * Add "everybody else" and us into it. They aren't - * playing, because we own the spinlock in the - * wait_queue_head. - */ - if (!atomic_add_negative(sleepers, &sem->count)) { - wake_up_locked(&sem->wait); - } - - spin_unlock_irqrestore(&sem->wait.lock, flags); - return 1; -} diff --git a/arch/m32r/kernel/Makefile b/arch/m32r/kernel/Makefile index e97e26e87c..09200d4886 100644 --- a/arch/m32r/kernel/Makefile +++ b/arch/m32r/kernel/Makefile @@ -5,7 +5,7 @@ extra-y := head.o init_task.o vmlinux.lds obj-y := process.o entry.o traps.o align.o irq.o setup.o time.o \ - m32r_ksyms.o sys_m32r.o semaphore.o signal.o ptrace.o + m32r_ksyms.o sys_m32r.o signal.o ptrace.o obj-$(CONFIG_SMP) += smp.o smpboot.o obj-$(CONFIG_MODULES) += module.o diff --git a/arch/m32r/kernel/m32r_ksyms.c b/arch/m32r/kernel/m32r_ksyms.c index 41a4c95e06..e6709fe950 100644 --- a/arch/m32r/kernel/m32r_ksyms.c +++ b/arch/m32r/kernel/m32r_ksyms.c @@ -7,7 +7,6 @@ #include #include -#include #include #include #include @@ -22,10 +21,6 @@ EXPORT_SYMBOL(dump_fpu); EXPORT_SYMBOL(__ioremap); EXPORT_SYMBOL(iounmap); EXPORT_SYMBOL(kernel_thread); -EXPORT_SYMBOL(__down); -EXPORT_SYMBOL(__down_interruptible); -EXPORT_SYMBOL(__up); -EXPORT_SYMBOL(__down_trylock); /* Networking helper routines. */ /* Delay loops */ diff --git a/arch/m32r/kernel/semaphore.c b/arch/m32r/kernel/semaphore.c deleted file mode 100644 index 940c2d37cf..0000000000 --- a/arch/m32r/kernel/semaphore.c +++ /dev/null @@ -1,185 +0,0 @@ -/* - * linux/arch/m32r/semaphore.c - * orig : i386 2.6.4 - * - * M32R semaphore implementation. - * - * Copyright (c) 2002 - 2004 Hitoshi Yamamoto - */ - -/* - * i386 semaphore implementation. - * - * (C) Copyright 1999 Linus Torvalds - * - * Portions Copyright 1999 Red Hat, Inc. - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public License - * as published by the Free Software Foundation; either version - * 2 of the License, or (at your option) any later version. - * - * rw semaphores implemented November 1999 by Benjamin LaHaise - */ -#include -#include -#include -#include - -/* - * Semaphores are implemented using a two-way counter: - * The "count" variable is decremented for each process - * that tries to acquire the semaphore, while the "sleeping" - * variable is a count of such acquires. - * - * Notably, the inline "up()" and "down()" functions can - * efficiently test if they need to do any extra work (up - * needs to do something only if count was negative before - * the increment operation. - * - * "sleeping" and the contention routine ordering is protected - * by the spinlock in the semaphore's waitqueue head. - * - * Note that these functions are only called when there is - * contention on the lock, and as such all this is the - * "non-critical" part of the whole semaphore business. The - * critical part is the inline stuff in - * where we want to avoid any extra jumps and calls. - */ - -/* - * Logic: - * - only on a boundary condition do we need to care. When we go - * from a negative count to a non-negative, we wake people up. - * - when we go from a non-negative count to a negative do we - * (a) synchronize with the "sleeper" count and (b) make sure - * that we're on the wakeup list before we synchronize so that - * we cannot lose wakeup events. - */ - -asmlinkage void __up(struct semaphore *sem) -{ - wake_up(&sem->wait); -} - -asmlinkage void __sched __down(struct semaphore * sem) -{ - struct task_struct *tsk = current; - DECLARE_WAITQUEUE(wait, tsk); - unsigned long flags; - - tsk->state = TASK_UNINTERRUPTIBLE; - spin_lock_irqsave(&sem->wait.lock, flags); - add_wait_queue_exclusive_locked(&sem->wait, &wait); - - sem->sleepers++; - for (;;) { - int sleepers = sem->sleepers; - - /* - * Add "everybody else" into it. They aren't - * playing, because we own the spinlock in - * the wait_queue_head. - */ - if (!atomic_add_negative(sleepers - 1, &sem->count)) { - sem->sleepers = 0; - break; - } - sem->sleepers = 1; /* us - see -1 above */ - spin_unlock_irqrestore(&sem->wait.lock, flags); - - schedule(); - - spin_lock_irqsave(&sem->wait.lock, flags); - tsk->state = TASK_UNINTERRUPTIBLE; - } - remove_wait_queue_locked(&sem->wait, &wait); - wake_up_locked(&sem->wait); - spin_unlock_irqrestore(&sem->wait.lock, flags); - tsk->state = TASK_RUNNING; -} - -asmlinkage int __sched __down_interruptible(struct semaphore * sem) -{ - int retval = 0; - struct task_struct *tsk = current; - DECLARE_WAITQUEUE(wait, tsk); - unsigned long flags; - - tsk->state = TASK_INTERRUPTIBLE; - spin_lock_irqsave(&sem->wait.lock, flags); - add_wait_queue_exclusive_locked(&sem->wait, &wait); - - sem->sleepers++; - for (;;) { - int sleepers = sem->sleepers; - - /* - * With signals pending, this turns into - * the trylock failure case - we won't be - * sleeping, and we* can't get the lock as - * it has contention. Just correct the count - * and exit. - */ - if (signal_pending(current)) { - retval = -EINTR; - sem->sleepers = 0; - atomic_add(sleepers, &sem->count); - break; - } - - /* - * Add "everybody else" into it. They aren't - * playing, because we own the spinlock in - * wait_queue_head. The "-1" is because we're - * still hoping to get the semaphore. - */ - if (!atomic_add_negative(sleepers - 1, &sem->count)) { - sem->sleepers = 0; - break; - } - sem->sleepers = 1; /* us - see -1 above */ - spin_unlock_irqrestore(&sem->wait.lock, flags); - - schedule(); - - spin_lock_irqsave(&sem->wait.lock, flags); - tsk->state = TASK_INTERRUPTIBLE; - } - remove_wait_queue_locked(&sem->wait, &wait); - wake_up_locked(&sem->wait); - spin_unlock_irqrestore(&sem->wait.lock, flags); - - tsk->state = TASK_RUNNING; - return retval; -} - -/* - * Trylock failed - make sure we correct for - * having decremented the count. - * - * We could have done the trylock with a - * single "cmpxchg" without failure cases, - * but then it wouldn't work on a 386. - */ -asmlinkage int __down_trylock(struct semaphore * sem) -{ - int sleepers; - unsigned long flags; - - spin_lock_irqsave(&sem->wait.lock, flags); - sleepers = sem->sleepers + 1; - sem->sleepers = 0; - - /* - * Add "everybody else" and us into it. They aren't - * playing, because we own the spinlock in the - * wait_queue_head. - */ - if (!atomic_add_negative(sleepers, &sem->count)) { - wake_up_locked(&sem->wait); - } - - spin_unlock_irqrestore(&sem->wait.lock, flags); - return 1; -} diff --git a/arch/m68k/kernel/Makefile b/arch/m68k/kernel/Makefile index a806208c7f..7a62a71814 100644 --- a/arch/m68k/kernel/Makefile +++ b/arch/m68k/kernel/Makefile @@ -10,7 +10,7 @@ endif extra-y += vmlinux.lds obj-y := entry.o process.o traps.o ints.o signal.o ptrace.o module.o \ - sys_m68k.o time.o semaphore.o setup.o m68k_ksyms.o devres.o + sys_m68k.o time.o setup.o m68k_ksyms.o devres.o devres-y = ../../../kernel/irq/devres.o diff --git a/arch/m68k/kernel/m68k_ksyms.c b/arch/m68k/kernel/m68k_ksyms.c index 6fc69c74fe..d900e77e53 100644 --- a/arch/m68k/kernel/m68k_ksyms.c +++ b/arch/m68k/kernel/m68k_ksyms.c @@ -1,5 +1,4 @@ #include -#include asmlinkage long long __ashldi3 (long long, int); asmlinkage long long __ashrdi3 (long long, int); @@ -15,8 +14,3 @@ EXPORT_SYMBOL(__ashrdi3); EXPORT_SYMBOL(__lshrdi3); EXPORT_SYMBOL(__muldi3); -EXPORT_SYMBOL(__down_failed); -EXPORT_SYMBOL(__down_failed_interruptible); -EXPORT_SYMBOL(__down_failed_trylock); -EXPORT_SYMBOL(__up_wakeup); - diff --git a/arch/m68k/kernel/semaphore.c b/arch/m68k/kernel/semaphore.c deleted file mode 100644 index d12cbbfe6e..0000000000 --- a/arch/m68k/kernel/semaphore.c +++ /dev/null @@ -1,132 +0,0 @@ -/* - * Generic semaphore code. Buyer beware. Do your own - * specific changes in - */ - -#include -#include -#include - -#ifndef CONFIG_RMW_INSNS -spinlock_t semaphore_wake_lock; -#endif - -/* - * Semaphores are implemented using a two-way counter: - * The "count" variable is decremented for each process - * that tries to sleep, while the "waking" variable is - * incremented when the "up()" code goes to wake up waiting - * processes. - * - * Notably, the inline "up()" and "down()" functions can - * efficiently test if they need to do any extra work (up - * needs to do something only if count was negative before - * the increment operation. - * - * waking_non_zero() (from asm/semaphore.h) must execute - * atomically. - * - * When __up() is called, the count was negative before - * incrementing it, and we need to wake up somebody. - * - * This routine adds one to the count of processes that need to - * wake up and exit. ALL waiting processes actually wake up but - * only the one that gets to the "waking" field first will gate - * through and acquire the semaphore. The others will go back - * to sleep. - * - * Note that these functions are only called when there is - * contention on the lock, and as such all this is the - * "non-critical" part of the whole semaphore business. The - * critical part is the inline stuff in - * where we want to avoid any extra jumps and calls. - */ -void __up(struct semaphore *sem) -{ - wake_one_more(sem); - wake_up(&sem->wait); -} - -/* - * Perform the "down" function. Return zero for semaphore acquired, - * return negative for signalled out of the function. - * - * If called from __down, the return is ignored and the wait loop is - * not interruptible. This means that a task waiting on a semaphore - * using "down()" cannot be killed until someone does an "up()" on - * the semaphore. - * - * If called from __down_interruptible, the return value gets checked - * upon return. If the return value is negative then the task continues - * with the negative value in the return register (it can be tested by - * the caller). - * - * Either form may be used in conjunction with "up()". - * - */ - - -#define DOWN_HEAD(task_state) \ - \ - \ - current->state = (task_state); \ - add_wait_queue(&sem->wait, &wait); \ - \ - /* \ - * Ok, we're set up. sem->count is known to be less than zero \ - * so we must wait. \ - * \ - * We can let go the lock for purposes of waiting. \ - * We re-acquire it after awaking so as to protect \ - * all semaphore operations. \ - * \ - * If "up()" is called before we call waking_non_zero() then \ - * we will catch it right away. If it is called later then \ - * we will have to go through a wakeup cycle to catch it. \ - * \ - * Multiple waiters contend for the semaphore lock to see \ - * who gets to gate through and who has to wait some more. \ - */ \ - for (;;) { - -#define DOWN_TAIL(task_state) \ - current->state = (task_state); \ - } \ - current->state = TASK_RUNNING; \ - remove_wait_queue(&sem->wait, &wait); - -void __sched __down(struct semaphore * sem) -{ - DECLARE_WAITQUEUE(wait, current); - - DOWN_HEAD(TASK_UNINTERRUPTIBLE) - if (waking_non_zero(sem)) - break; - schedule(); - DOWN_TAIL(TASK_UNINTERRUPTIBLE) -} - -int __sched __down_interruptible(struct semaphore * sem) -{ - DECLARE_WAITQUEUE(wait, current); - int ret = 0; - - DOWN_HEAD(TASK_INTERRUPTIBLE) - - ret = waking_non_zero_interruptible(sem, current); - if (ret) - { - if (ret == 1) - /* ret != 0 only if we get interrupted -arca */ - ret = 0; - break; - } - schedule(); - DOWN_TAIL(TASK_INTERRUPTIBLE) - return ret; -} - -int __down_trylock(struct semaphore * sem) -{ - return waking_non_zero_trylock(sem); -} diff --git a/arch/m68k/lib/Makefile b/arch/m68k/lib/Makefile index 6bbf19f960..a18af095cd 100644 --- a/arch/m68k/lib/Makefile +++ b/arch/m68k/lib/Makefile @@ -5,4 +5,4 @@ EXTRA_AFLAGS := -traditional lib-y := ashldi3.o ashrdi3.o lshrdi3.o muldi3.o \ - checksum.o string.o semaphore.o uaccess.o + checksum.o string.o uaccess.o diff --git a/arch/m68k/lib/semaphore.S b/arch/m68k/lib/semaphore.S deleted file mode 100644 index 0215624c16..0000000000 --- a/arch/m68k/lib/semaphore.S +++ /dev/null @@ -1,53 +0,0 @@ -/* - * linux/arch/m68k/lib/semaphore.S - * - * Copyright (C) 1996 Linus Torvalds - * - * m68k version by Andreas Schwab - */ - -#include -#include - -/* - * The semaphore operations have a special calling sequence that - * allow us to do a simpler in-line version of them. These routines - * need to convert that sequence back into the C sequence when - * there is contention on the semaphore. - */ -ENTRY(__down_failed) - moveml %a0/%d0/%d1,-(%sp) - movel %a1,-(%sp) - jbsr __down - movel (%sp)+,%a1 - moveml (%sp)+,%a0/%d0/%d1 - rts - -ENTRY(__down_failed_interruptible) - movel %a0,-(%sp) - movel %d1,-(%sp) - movel %a1,-(%sp) - jbsr __down_interruptible - movel (%sp)+,%a1 - movel (%sp)+,%d1 - movel (%sp)+,%a0 - rts - -ENTRY(__down_failed_trylock) - movel %a0,-(%sp) - movel %d1,-(%sp) - movel %a1,-(%sp) - jbsr __down_trylock - movel (%sp)+,%a1 - movel (%sp)+,%d1 - movel (%sp)+,%a0 - rts - -ENTRY(__up_wakeup) - moveml %a0/%d0/%d1,-(%sp) - movel %a1,-(%sp) - jbsr __up - movel (%sp)+,%a1 - moveml (%sp)+,%a0/%d0/%d1 - rts - diff --git a/arch/m68knommu/kernel/Makefile b/arch/m68knommu/kernel/Makefile index 1524b39ad6..f0eab3dedb 100644 --- a/arch/m68knommu/kernel/Makefile +++ b/arch/m68knommu/kernel/Makefile @@ -5,7 +5,7 @@ extra-y := vmlinux.lds obj-y += dma.o entry.o init_task.o irq.o m68k_ksyms.o process.o ptrace.o \ - semaphore.o setup.o signal.o syscalltable.o sys_m68k.o time.o traps.o + setup.o signal.o syscalltable.o sys_m68k.o time.o traps.o obj-$(CONFIG_MODULES) += module.o obj-$(CONFIG_COMEMPCI) += comempci.o diff --git a/arch/m68knommu/kernel/m68k_ksyms.c b/arch/m68knommu/kernel/m68k_ksyms.c index 53fad14902..39fe0a7aec 100644 --- a/arch/m68knommu/kernel/m68k_ksyms.c +++ b/arch/m68knommu/kernel/m68k_ksyms.c @@ -13,7 +13,6 @@ #include #include #include -#include #include #include @@ -39,11 +38,6 @@ EXPORT_SYMBOL(csum_partial_copy_nocheck); EXPORT_SYMBOL(memcpy); EXPORT_SYMBOL(memset); -EXPORT_SYMBOL(__down_failed); -EXPORT_SYMBOL(__down_failed_interruptible); -EXPORT_SYMBOL(__down_failed_trylock); -EXPORT_SYMBOL(__up_wakeup); - /* * libgcc functions - functions that are used internally by the * compiler... (prototypes are not correct though, but that diff --git a/arch/m68knommu/kernel/semaphore.c b/arch/m68knommu/kernel/semaphore.c deleted file mode 100644 index bce2bc7d87..0000000000 --- a/arch/m68knommu/kernel/semaphore.c +++ /dev/null @@ -1,133 +0,0 @@ -/* - * Generic semaphore code. Buyer beware. Do your own - * specific changes in - */ - -#include -#include -#include -#include - -#ifndef CONFIG_RMW_INSNS -spinlock_t semaphore_wake_lock; -#endif - -/* - * Semaphores are implemented using a two-way counter: - * The "count" variable is decremented for each process - * that tries to sleep, while the "waking" variable is - * incremented when the "up()" code goes to wake up waiting - * processes. - * - * Notably, the inline "up()" and "down()" functions can - * efficiently test if they need to do any extra work (up - * needs to do something only if count was negative before - * the increment operation. - * - * waking_non_zero() (from asm/semaphore.h) must execute - * atomically. - * - * When __up() is called, the count was negative before - * incrementing it, and we need to wake up somebody. - * - * This routine adds one to the count of processes that need to - * wake up and exit. ALL waiting processes actually wake up but - * only the one that gets to the "waking" field first will gate - * through and acquire the semaphore. The others will go back - * to sleep. - * - * Note that these functions are only called when there is - * contention on the lock, and as such all this is the - * "non-critical" part of the whole semaphore business. The - * critical part is the inline stuff in - * where we want to avoid any extra jumps and calls. - */ -void __up(struct semaphore *sem) -{ - wake_one_more(sem); - wake_up(&sem->wait); -} - -/* - * Perform the "down" function. Return zero for semaphore acquired, - * return negative for signalled out of the function. - * - * If called from __down, the return is ignored and the wait loop is - * not interruptible. This means that a task waiting on a semaphore - * using "down()" cannot be killed until someone does an "up()" on - * the semaphore. - * - * If called from __down_interruptible, the return value gets checked - * upon return. If the return value is negative then the task continues - * with the negative value in the return register (it can be tested by - * the caller). - * - * Either form may be used in conjunction with "up()". - * - */ - - -#define DOWN_HEAD(task_state) \ - \ - \ - current->state = (task_state); \ - add_wait_queue(&sem->wait, &wait); \ - \ - /* \ - * Ok, we're set up. sem->count is known to be less than zero \ - * so we must wait. \ - * \ - * We can let go the lock for purposes of waiting. \ - * We re-acquire it after awaking so as to protect \ - * all semaphore operations. \ - * \ - * If "up()" is called before we call waking_non_zero() then \ - * we will catch it right away. If it is called later then \ - * we will have to go through a wakeup cycle to catch it. \ - * \ - * Multiple waiters contend for the semaphore lock to see \ - * who gets to gate through and who has to wait some more. \ - */ \ - for (;;) { - -#define DOWN_TAIL(task_state) \ - current->state = (task_state); \ - } \ - current->state = TASK_RUNNING; \ - remove_wait_queue(&sem->wait, &wait); - -void __sched __down(struct semaphore * sem) -{ - DECLARE_WAITQUEUE(wait, current); - - DOWN_HEAD(TASK_UNINTERRUPTIBLE) - if (waking_non_zero(sem)) - break; - schedule(); - DOWN_TAIL(TASK_UNINTERRUPTIBLE) -} - -int __sched __down_interruptible(struct semaphore * sem) -{ - DECLARE_WAITQUEUE(wait, current); - int ret = 0; - - DOWN_HEAD(TASK_INTERRUPTIBLE) - - ret = waking_non_zero_interruptible(sem, current); - if (ret) - { - if (ret == 1) - /* ret != 0 only if we get interrupted -arca */ - ret = 0; - break; - } - schedule(); - DOWN_TAIL(TASK_INTERRUPTIBLE) - return ret; -} - -int __down_trylock(struct semaphore * sem) -{ - return waking_non_zero_trylock(sem); -} diff --git a/arch/m68knommu/lib/Makefile b/arch/m68knommu/lib/Makefile index e051a79139..d94d709665 100644 --- a/arch/m68knommu/lib/Makefile +++ b/arch/m68knommu/lib/Makefile @@ -4,4 +4,4 @@ lib-y := ashldi3.o ashrdi3.o lshrdi3.o \ muldi3.o mulsi3.o divsi3.o udivsi3.o modsi3.o umodsi3.o \ - checksum.o semaphore.o memcpy.o memset.o delay.o + checksum.o memcpy.o memset.o delay.o diff --git a/arch/m68knommu/lib/semaphore.S b/arch/m68knommu/lib/semaphore.S deleted file mode 100644 index 87c7460343..0000000000 --- a/arch/m68knommu/lib/semaphore.S +++ /dev/null @@ -1,66 +0,0 @@ -/* - * linux/arch/m68k/lib/semaphore.S - * - * Copyright (C) 1996 Linus Torvalds - * - * m68k version by Andreas Schwab - * - * MAR/1999 -- modified to support ColdFire (gerg@snapgear.com) - */ - -#include -#include - -/* - * "down_failed" is called with the eventual return address - * in %a0, and the address of the semaphore in %a1. We need - * to increment the number of waiters on the semaphore, - * call "__down()", and then eventually return to try again. - */ -ENTRY(__down_failed) -#ifdef CONFIG_COLDFIRE - subl #12,%sp - moveml %a0/%d0/%d1,(%sp) -#else - moveml %a0/%d0/%d1,-(%sp) -#endif - movel %a1,-(%sp) - jbsr __down - movel (%sp)+,%a1 - movel (%sp)+,%d0 - movel (%sp)+,%d1 - rts - -ENTRY(__down_failed_interruptible) - movel %a0,-(%sp) - movel %d1,-(%sp) - movel %a1,-(%sp) - jbsr __down_interruptible - movel (%sp)+,%a1 - movel (%sp)+,%d1 - rts - -ENTRY(__up_wakeup) -#ifdef CONFIG_COLDFIRE - subl #12,%sp - moveml %a0/%d0/%d1,(%sp) -#else - moveml %a0/%d0/%d1,-(%sp) -#endif - movel %a1,-(%sp) - jbsr __up - movel (%sp)+,%a1 - movel (%sp)+,%d0 - movel (%sp)+,%d1 - rts - -ENTRY(__down_failed_trylock) - movel %a0,-(%sp) - movel %d1,-(%sp) - movel %a1,-(%sp) - jbsr __down_trylock - movel (%sp)+,%a1 - movel (%sp)+,%d1 - movel (%sp)+,%a0 - rts - diff --git a/arch/mips/kernel/Makefile b/arch/mips/kernel/Makefile index 9e78e1a4ca..6fcdb6fda2 100644 --- a/arch/mips/kernel/Makefile +++ b/arch/mips/kernel/Makefile @@ -5,7 +5,7 @@ extra-y := head.o init_task.o vmlinux.lds obj-y += cpu-probe.o branch.o entry.o genex.o irq.o process.o \ - ptrace.o reset.o semaphore.o setup.o signal.o syscall.o \ + ptrace.o reset.o setup.o signal.o syscall.o \ time.o topology.o traps.o unaligned.o obj-$(CONFIG_CEVT_BCM1480) += cevt-bcm1480.o diff --git a/arch/mips/kernel/semaphore.c b/arch/mips/kernel/semaphore.c deleted file mode 100644 index 1265358cdc..0000000000 --- a/arch/mips/kernel/semaphore.c +++ /dev/null @@ -1,168 +0,0 @@ -/* - * MIPS-specific semaphore code. - * - * Copyright (C) 1999 Cort Dougan - * Copyright (C) 2004 Ralf Baechle - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public License - * as published by the Free Software Foundation; either version - * 2 of the License, or (at your option) any later version. - * - * April 2001 - Reworked by Paul Mackerras - * to eliminate the SMP races in the old version between the updates - * of `count' and `waking'. Now we use negative `count' values to - * indicate that some process(es) are waiting for the semaphore. - */ - -#include -#include -#include -#include -#include -#include -#include -#include -/* - * Atomically update sem->count. - * This does the equivalent of the following: - * - * old_count = sem->count; - * tmp = MAX(old_count, 0) + incr; - * sem->count = tmp; - * return old_count; - * - * On machines without lld/scd we need a spinlock to make the manipulation of - * sem->count and sem->waking atomic. Scalability isn't an issue because - * this lock is used on UP only so it's just an empty variable. - */ -static inline int __sem_update_count(struct semaphore *sem, int incr) -{ - int old_count, tmp; - - if (cpu_has_llsc && R10000_LLSC_WAR) { - __asm__ __volatile__( - " .set mips3 \n" - "1: ll %0, %2 # __sem_update_count \n" - " sra %1, %0, 31 \n" - " not %1 \n" - " and %1, %0, %1 \n" - " addu %1, %1, %3 \n" - " sc %1, %2 \n" - " beqzl %1, 1b \n" - " .set mips0 \n" - : "=&r" (old_count), "=&r" (tmp), "=m" (sem->count) - : "r" (incr), "m" (sem->count)); - } else if (cpu_has_llsc) { - __asm__ __volatile__( - " .set mips3 \n" - "1: ll %0, %2 # __sem_update_count \n" - " sra %1, %0, 31 \n" - " not %1 \n" - " and %1, %0, %1 \n" - " addu %1, %1, %3 \n" - " sc %1, %2 \n" - " beqz %1, 1b \n" - " .set mips0 \n" - : "=&r" (old_count), "=&r" (tmp), "=m" (sem->count) - : "r" (incr), "m" (sem->count)); - } else { - static DEFINE_SPINLOCK(semaphore_lock); - unsigned long flags; - - spin_lock_irqsave(&semaphore_lock, flags); - old_count = atomic_read(&sem->count); - tmp = max_t(int, old_count, 0) + incr; - atomic_set(&sem->count, tmp); - spin_unlock_irqrestore(&semaphore_lock, flags); - } - - return old_count; -} - -void __up(struct semaphore *sem) -{ - /* - * Note that we incremented count in up() before we came here, - * but that was ineffective since the result was <= 0, and - * any negative value of count is equivalent to 0. - * This ends up setting count to 1, unless count is now > 0 - * (i.e. because some other cpu has called up() in the meantime), - * in which case we just increment count. - */ - __sem_update_count(sem, 1); - wake_up(&sem->wait); -} - -EXPORT_SYMBOL(__up); - -/* - * Note that when we come in to __down or __down_interruptible, - * we have already decremented count, but that decrement was - * ineffective since the result was < 0, and any negative value - * of count is equivalent to 0. - * Thus it is only when we decrement count from some value > 0 - * that we have actually got the semaphore. - */ -void __sched __down(struct semaphore *sem) -{ - struct task_struct *tsk = current; - DECLARE_WAITQUEUE(wait, tsk); - - __set_task_state(tsk, TASK_UNINTERRUPTIBLE); - add_wait_queue_exclusive(&sem->wait, &wait); - - /* - * Try to get the semaphore. If the count is > 0, then we've - * got the semaphore; we decrement count and exit the loop. - * If the count is 0 or negative, we set it to -1, indicating - * that we are asleep, and then sleep. - */ - while (__sem_update_count(sem, -1) <= 0) { - schedule(); - set_task_state(tsk, TASK_UNINTERRUPTIBLE); - } - remove_wait_queue(&sem->wait, &wait); - __set_task_state(tsk, TASK_RUNNING); - - /* - * If there are any more sleepers, wake one of them up so - * that it can either get the semaphore, or set count to -1 - * indicating that there are still processes sleeping. - */ - wake_up(&sem->wait); -} - -EXPORT_SYMBOL(__down); - -int __sched __down_interruptible(struct semaphore * sem) -{ - int retval = 0; - struct task_struct *tsk = current; - DECLARE_WAITQUEUE(wait, tsk); - - __set_task_state(tsk, TASK_INTERRUPTIBLE); - add_wait_queue_exclusive(&sem->wait, &wait); - - while (__sem_update_count(sem, -1) <= 0) { - if (signal_pending(current)) { - /* - * A signal is pending - give up trying. - * Set sem->count to 0 if it is negative, - * since we are no longer sleeping. - */ - __sem_update_count(sem, 0); - retval = -EINTR; - break; - } - schedule(); - set_task_state(tsk, TASK_INTERRUPTIBLE); - } - remove_wait_queue(&sem->wait, &wait); - __set_task_state(tsk, TASK_RUNNING); - - wake_up(&sem->wait); - return retval; -} - -EXPORT_SYMBOL(__down_interruptible); diff --git a/arch/mn10300/kernel/Makefile b/arch/mn10300/kernel/Makefile index ef07c95617..23f2ab6757 100644 --- a/arch/mn10300/kernel/Makefile +++ b/arch/mn10300/kernel/Makefile @@ -3,7 +3,7 @@ # extra-y := head.o init_task.o vmlinux.lds -obj-y := process.o semaphore.o signal.o entry.o fpu.o traps.o irq.o \ +obj-y := process.o signal.o entry.o fpu.o traps.o irq.o \ ptrace.o setup.o time.o sys_mn10300.o io.o kthread.o \ switch_to.o mn10300_ksyms.o kernel_execve.o diff --git a/arch/mn10300/kernel/semaphore.c b/arch/mn10300/kernel/semaphore.c deleted file mode 100644 index 9153c4039f..0000000000 --- a/arch/mn10300/kernel/semaphore.c +++ /dev/null @@ -1,149 +0,0 @@ -/* MN10300 Semaphore implementation - * - * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved. - * Written by David Howells (dhowells@redhat.com) - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public Licence - * as published by the Free Software Foundation; either version - * 2 of the Licence, or (at your option) any later version. - */ -#include -#include -#include - -struct sem_waiter { - struct list_head list; - struct task_struct *task; -}; - -#if SEMAPHORE_DEBUG -void semtrace(struct semaphore *sem, const char *str) -{ - if (sem->debug) - printk(KERN_DEBUG "[%d] %s({%d,%d})\n", - current->pid, - str, - atomic_read(&sem->count), - list_empty(&sem->wait_list) ? 0 : 1); -} -#else -#define semtrace(SEM, STR) do { } while (0) -#endif - -/* - * wait for a token to be granted from a semaphore - * - entered with lock held and interrupts disabled - */ -void __down(struct semaphore *sem, unsigned long flags) -{ - struct task_struct *tsk = current; - struct sem_waiter waiter; - - semtrace(sem, "Entering __down"); - - /* set up my own style of waitqueue */ - waiter.task = tsk; - get_task_struct(tsk); - - list_add_tail(&waiter.list, &sem->wait_list); - - /* we don't need to touch the semaphore struct anymore */ - spin_unlock_irqrestore(&sem->wait_lock, flags); - - /* wait to be given the semaphore */ - set_task_state(tsk, TASK_UNINTERRUPTIBLE); - - for (;;) { - if (!waiter.task) - break; - schedule(); - set_task_state(tsk, TASK_UNINTERRUPTIBLE); - } - - tsk->state = TASK_RUNNING; - semtrace(sem, "Leaving __down"); -} -EXPORT_SYMBOL(__down); - -/* - * interruptibly wait for a token to be granted from a semaphore - * - entered with lock held and interrupts disabled - */ -int __down_interruptible(struct semaphore *sem, unsigned long flags) -{ - struct task_struct *tsk = current; - struct sem_waiter waiter; - int ret; - - semtrace(sem, "Entering __down_interruptible"); - - /* set up my own style of waitqueue */ - waiter.task = tsk; - get_task_struct(tsk); - - list_add_tail(&waiter.list, &sem->wait_list); - - /* we don't need to touch the semaphore struct anymore */ - set_task_state(tsk, TASK_INTERRUPTIBLE); - - spin_unlock_irqrestore(&sem->wait_lock, flags); - - /* wait to be given the semaphore */ - ret = 0; - for (;;) { - if (!waiter.task) - break; - if (unlikely(signal_pending(current))) - goto interrupted; - schedule(); - set_task_state(tsk, TASK_INTERRUPTIBLE); - } - - out: - tsk->state = TASK_RUNNING; - semtrace(sem, "Leaving __down_interruptible"); - return ret; - - interrupted: - spin_lock_irqsave(&sem->wait_lock, flags); - list_del(&waiter.list); - spin_unlock_irqrestore(&sem->wait_lock, flags); - - ret = 0; - if (!waiter.task) { - put_task_struct(current); - ret = -EINTR; - } - goto out; -} -EXPORT_SYMBOL(__down_interruptible); - -/* - * release a single token back to a semaphore - * - entered with lock held and interrupts disabled - */ -void __up(struct semaphore *sem) -{ - struct task_struct *tsk; - struct sem_waiter *waiter; - - semtrace(sem, "Entering __up"); - - /* grant the token to the process at the front of the queue */ - waiter = list_entry(sem->wait_list.next, struct sem_waiter, list); - - /* We must be careful not to touch 'waiter' after we set ->task = NULL. - * It is an allocated on the waiter's stack and may become invalid at - * any time after that point (due to a wakeup from another source). - */ - list_del_init(&waiter->list); - tsk = waiter->task; - smp_mb(); - waiter->task = NULL; - wake_up_process(tsk); - put_task_struct(tsk); - - semtrace(sem, "Leaving __up"); -} -EXPORT_SYMBOL(__up); diff --git a/arch/parisc/kernel/Makefile b/arch/parisc/kernel/Makefile index 27827bc371..1f6585a56f 100644 --- a/arch/parisc/kernel/Makefile +++ b/arch/parisc/kernel/Makefile @@ -9,7 +9,7 @@ AFLAGS_pacache.o := -traditional obj-y := cache.o pacache.o setup.o traps.o time.o irq.o \ pa7300lc.o syscall.o entry.o sys_parisc.o firmware.o \ - ptrace.o hardware.o inventory.o drivers.o semaphore.o \ + ptrace.o hardware.o inventory.o drivers.o \ signal.o hpmc.o real2.o parisc_ksyms.o unaligned.o \ process.o processor.o pdc_cons.o pdc_chassis.o unwind.o \ topology.o diff --git a/arch/parisc/kernel/parisc_ksyms.c b/arch/parisc/kernel/parisc_ksyms.c index 7aca704e96..5b7fc4aa04 100644 --- a/arch/parisc/kernel/parisc_ksyms.c +++ b/arch/parisc/kernel/parisc_ksyms.c @@ -69,11 +69,6 @@ EXPORT_SYMBOL(memcpy_toio); EXPORT_SYMBOL(memcpy_fromio); EXPORT_SYMBOL(memset_io); -#include -EXPORT_SYMBOL(__up); -EXPORT_SYMBOL(__down_interruptible); -EXPORT_SYMBOL(__down); - extern void $$divI(void); extern void $$divU(void); extern void $$remI(void); diff --git a/arch/parisc/kernel/semaphore.c b/arch/parisc/kernel/semaphore.c deleted file mode 100644 index ee806bcc37..0000000000 --- a/arch/parisc/kernel/semaphore.c +++ /dev/null @@ -1,102 +0,0 @@ -/* - * Semaphore implementation Copyright (c) 2001 Matthew Wilcox, Hewlett-Packard - */ - -#include -#include -#include -#include - -/* - * Semaphores are complex as we wish to avoid using two variables. - * `count' has multiple roles, depending on its value. If it is positive - * or zero, there are no waiters. The functions here will never be - * called; see - * - * When count is -1 it indicates there is at least one task waiting - * for the semaphore. - * - * When count is less than that, there are '- count - 1' wakeups - * pending. ie if it has value -3, there are 2 wakeups pending. - * - * Note that these functions are only called when there is contention - * on the lock, and as such all this is the "non-critical" part of the - * whole semaphore business. The critical part is the inline stuff in - * where we want to avoid any extra jumps and calls. - */ -void __up(struct semaphore *sem) -{ - sem->count--; - wake_up(&sem->wait); -} - -#define wakers(count) (-1 - count) - -#define DOWN_HEAD \ - int ret = 0; \ - DECLARE_WAITQUEUE(wait, current); \ - \ - /* Note that someone is waiting */ \ - if (sem->count == 0) \ - sem->count = -1; \ - \ - /* protected by the sentry still -- use unlocked version */ \ - wait.flags = WQ_FLAG_EXCLUSIVE; \ - __add_wait_queue_tail(&sem->wait, &wait); \ - lost_race: \ - spin_unlock_irq(&sem->sentry); \ - -#define DOWN_TAIL \ - spin_lock_irq(&sem->sentry); \ - if (wakers(sem->count) == 0 && ret == 0) \ - goto lost_race; /* Someone stole our wakeup */ \ - __remove_wait_queue(&sem->wait, &wait); \ - current->state = TASK_RUNNING; \ - if (!waitqueue_active(&sem->wait) && (sem->count < 0)) \ - sem->count = wakers(sem->count); - -#define UPDATE_COUNT \ - sem->count += (sem->count < 0) ? 1 : - 1; - - -void __sched __down(struct semaphore * sem) -{ - DOWN_HEAD - - for(;;) { - set_task_state(current, TASK_UNINTERRUPTIBLE); - /* we can _read_ this without the sentry */ - if (sem->count != -1) - break; - schedule(); - } - - DOWN_TAIL - UPDATE_COUNT -} - -int __sched __down_interruptible(struct semaphore * sem) -{ - DOWN_HEAD - - for(;;) { - set_task_state(current, TASK_INTERRUPTIBLE); - /* we can _read_ this without the sentry */ - if (sem->count != -1) - break; - - if (signal_pending(current)) { - ret = -EINTR; - break; - } - schedule(); - } - - DOWN_TAIL - - if (!ret) { - UPDATE_COUNT - } - - return ret; -} diff --git a/arch/powerpc/kernel/Makefile b/arch/powerpc/kernel/Makefile index c1baf9d590..b9dbfff9af 100644 --- a/arch/powerpc/kernel/Makefile +++ b/arch/powerpc/kernel/Makefile @@ -12,7 +12,7 @@ CFLAGS_prom_init.o += -fPIC CFLAGS_btext.o += -fPIC endif -obj-y := semaphore.o cputable.o ptrace.o syscalls.o \ +obj-y := cputable.o ptrace.o syscalls.o \ irq.o align.o signal_32.o pmc.o vdso.o \ init_task.o process.o systbl.o idle.o \ signal.o diff --git a/arch/powerpc/kernel/ppc_ksyms.c b/arch/powerpc/kernel/ppc_ksyms.c index 9c98424277..65d14e6ddc 100644 --- a/arch/powerpc/kernel/ppc_ksyms.c +++ b/arch/powerpc/kernel/ppc_ksyms.c @@ -15,7 +15,6 @@ #include #include -#include #include #include #include diff --git a/arch/powerpc/kernel/semaphore.c b/arch/powerpc/kernel/semaphore.c deleted file mode 100644 index 2f8c3c9513..0000000000 --- a/arch/powerpc/kernel/semaphore.c +++ /dev/null @@ -1,135 +0,0 @@ -/* - * PowerPC-specific semaphore code. - * - * Copyright (C) 1999 Cort Dougan - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public License - * as published by the Free Software Foundation; either version - * 2 of the License, or (at your option) any later version. - * - * April 2001 - Reworked by Paul Mackerras - * to eliminate the SMP races in the old version between the updates - * of `count' and `waking'. Now we use negative `count' values to - * indicate that some process(es) are waiting for the semaphore. - */ - -#include -#include -#include - -#include -#include -#include - -/* - * Atomically update sem->count. - * This does the equivalent of the following: - * - * old_count = sem->count; - * tmp = MAX(old_count, 0) + incr; - * sem->count = tmp; - * return old_count; - */ -static inline int __sem_update_count(struct semaphore *sem, int incr) -{ - int old_count, tmp; - - __asm__ __volatile__("\n" -"1: lwarx %0,0,%3\n" -" srawi %1,%0,31\n" -" andc %1,%0,%1\n" -" add %1,%1,%4\n" - PPC405_ERR77(0,%3) -" stwcx. %1,0,%3\n" -" bne 1b" - : "=&r" (old_count), "=&r" (tmp), "=m" (sem->count) - : "r" (&sem->count), "r" (incr), "m" (sem->count) - : "cc"); - - return old_count; -} - -void __up(struct semaphore *sem) -{ - /* - * Note that we incremented count in up() before we came here, - * but that was ineffective since the result was <= 0, and - * any negative value of count is equivalent to 0. - * This ends up setting count to 1, unless count is now > 0 - * (i.e. because some other cpu has called up() in the meantime), - * in which case we just increment count. - */ - __sem_update_count(sem, 1); - wake_up(&sem->wait); -} -EXPORT_SYMBOL(__up); - -/* - * Note that when we come in to __down or __down_interruptible, - * we have already decremented count, but that decrement was - * ineffective since the result was < 0, and any negative value - * of count is equivalent to 0. - * Thus it is only when we decrement count from some value > 0 - * that we have actually got the semaphore. - */ -void __sched __down(struct semaphore *sem) -{ - struct task_struct *tsk = current; - DECLARE_WAITQUEUE(wait, tsk); - - __set_task_state(tsk, TASK_UNINTERRUPTIBLE); - add_wait_queue_exclusive(&sem->wait, &wait); - - /* - * Try to get the semaphore. If the count is > 0, then we've - * got the semaphore; we decrement count and exit the loop. - * If the count is 0 or negative, we set it to -1, indicating - * that we are asleep, and then sleep. - */ - while (__sem_update_count(sem, -1) <= 0) { - schedule(); - set_task_state(tsk, TASK_UNINTERRUPTIBLE); - } - remove_wait_queue(&sem->wait, &wait); - __set_task_state(tsk, TASK_RUNNING); - - /* - * If there are any more sleepers, wake one of them up so - * that it can either get the semaphore, or set count to -1 - * indicating that there are still processes sleeping. - */ - wake_up(&sem->wait); -} -EXPORT_SYMBOL(__down); - -int __sched __down_interruptible(struct semaphore * sem) -{ - int retval = 0; - struct task_struct *tsk = current; - DECLARE_WAITQUEUE(wait, tsk); - - __set_task_state(tsk, TASK_INTERRUPTIBLE); - add_wait_queue_exclusive(&sem->wait, &wait); - - while (__sem_update_count(sem, -1) <= 0) { - if (signal_pending(current)) { - /* - * A signal is pending - give up trying. - * Set sem->count to 0 if it is negative, - * since we are no longer sleeping. - */ - __sem_update_count(sem, 0); - retval = -EINTR; - break; - } - schedule(); - set_task_state(tsk, TASK_INTERRUPTIBLE); - } - remove_wait_queue(&sem->wait, &wait); - __set_task_state(tsk, TASK_RUNNING); - - wake_up(&sem->wait); - return retval; -} -EXPORT_SYMBOL(__down_interruptible); diff --git a/arch/ppc/kernel/semaphore.c b/arch/ppc/kernel/semaphore.c deleted file mode 100644 index 2fe429b27c..0000000000 --- a/arch/ppc/kernel/semaphore.c +++ /dev/null @@ -1,131 +0,0 @@ -/* - * PowerPC-specific semaphore code. - * - * Copyright (C) 1999 Cort Dougan - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public License - * as published by the Free Software Foundation; either version - * 2 of the License, or (at your option) any later version. - * - * April 2001 - Reworked by Paul Mackerras - * to eliminate the SMP races in the old version between the updates - * of `count' and `waking'. Now we use negative `count' values to - * indicate that some process(es) are waiting for the semaphore. - */ - -#include -#include -#include -#include -#include - -/* - * Atomically update sem->count. - * This does the equivalent of the following: - * - * old_count = sem->count; - * tmp = MAX(old_count, 0) + incr; - * sem->count = tmp; - * return old_count; - */ -static inline int __sem_update_count(struct semaphore *sem, int incr) -{ - int old_count, tmp; - - __asm__ __volatile__("\n" -"1: lwarx %0,0,%3\n" -" srawi %1,%0,31\n" -" andc %1,%0,%1\n" -" add %1,%1,%4\n" - PPC405_ERR77(0,%3) -" stwcx. %1,0,%3\n" -" bne 1b" - : "=&r" (old_count), "=&r" (tmp), "=m" (sem->count) - : "r" (&sem->count), "r" (incr), "m" (sem->count) - : "cc"); - - return old_count; -} - -void __up(struct semaphore *sem) -{ - /* - * Note that we incremented count in up() before we came here, - * but that was ineffective since the result was <= 0, and - * any negative value of count is equivalent to 0. - * This ends up setting count to 1, unless count is now > 0 - * (i.e. because some other cpu has called up() in the meantime), - * in which case we just increment count. - */ - __sem_update_count(sem, 1); - wake_up(&sem->wait); -} - -/* - * Note that when we come in to __down or __down_interruptible, - * we have already decremented count, but that decrement was - * ineffective since the result was < 0, and any negative value - * of count is equivalent to 0. - * Thus it is only when we decrement count from some value > 0 - * that we have actually got the semaphore. - */ -void __sched __down(struct semaphore *sem) -{ - struct task_struct *tsk = current; - DECLARE_WAITQUEUE(wait, tsk); - - tsk->state = TASK_UNINTERRUPTIBLE; - add_wait_queue_exclusive(&sem->wait, &wait); - smp_wmb(); - - /* - * Try to get the semaphore. If the count is > 0, then we've - * got the semaphore; we decrement count and exit the loop. - * If the count is 0 or negative, we set it to -1, indicating - * that we are asleep, and then sleep. - */ - while (__sem_update_count(sem, -1) <= 0) { - schedule(); - tsk->state = TASK_UNINTERRUPTIBLE; - } - remove_wait_queue(&sem->wait, &wait); - tsk->state = TASK_RUNNING; - - /* - * If there are any more sleepers, wake one of them up so - * that it can either get the semaphore, or set count to -1 - * indicating that there are still processes sleeping. - */ - wake_up(&sem->wait); -} - -int __sched __down_interruptible(struct semaphore * sem) -{ - int retval = 0; - struct task_struct *tsk = current; - DECLARE_WAITQUEUE(wait, tsk); - - tsk->state = TASK_INTERRUPTIBLE; - add_wait_queue_exclusive(&sem->wait, &wait); - smp_wmb(); - - while (__sem_update_count(sem, -1) <= 0) { - if (signal_pending(current)) { - /* - * A signal is pending - give up trying. - * Set sem->count to 0 if it is negative, - * since we are no longer sleeping. - */ - __sem_update_count(sem, 0); - retval = -EINTR; - break; - } - schedule(); - tsk->state = TASK_INTERRUPTIBLE; - } - tsk->state = TASK_RUNNING; - remove_wait_queue(&sem->wait, &wait); - wake_up(&sem->wait); - return retval; -} diff --git a/arch/s390/kernel/Makefile b/arch/s390/kernel/Makefile index 4d3e38392c..ce144b67f0 100644 --- a/arch/s390/kernel/Makefile +++ b/arch/s390/kernel/Makefile @@ -11,7 +11,7 @@ CFLAGS_smp.o := -Wno-nonnull obj-y := bitmap.o traps.o time.o process.o base.o early.o \ setup.o sys_s390.o ptrace.o signal.o cpcmd.o ebcdic.o \ - semaphore.o s390_ext.o debug.o irq.o ipl.o dis.o diag.o + s390_ext.o debug.o irq.o ipl.o dis.o diag.o obj-y += $(if $(CONFIG_64BIT),entry64.o,entry.o) obj-y += $(if $(CONFIG_64BIT),reipl64.o,reipl.o) diff --git a/arch/s390/kernel/s390_ksyms.c b/arch/s390/kernel/s390_ksyms.c index 7234c737f8..48238a114c 100644 --- a/arch/s390/kernel/s390_ksyms.c +++ b/arch/s390/kernel/s390_ksyms.c @@ -26,13 +26,6 @@ EXPORT_SYMBOL(_ni_bitmap); EXPORT_SYMBOL(_zb_findmap); EXPORT_SYMBOL(_sb_findmap); -/* - * semaphore ops - */ -EXPORT_SYMBOL(__up); -EXPORT_SYMBOL(__down); -EXPORT_SYMBOL(__down_interruptible); - /* * binfmt_elf loader */ diff --git a/arch/s390/kernel/semaphore.c b/arch/s390/kernel/semaphore.c deleted file mode 100644 index 191303f6c1..0000000000 --- a/arch/s390/kernel/semaphore.c +++ /dev/null @@ -1,108 +0,0 @@ -/* - * linux/arch/s390/kernel/semaphore.c - * - * S390 version - * Copyright (C) 1998-2000 IBM Corporation - * Author(s): Martin Schwidefsky - * - * Derived from "linux/arch/i386/kernel/semaphore.c - * Copyright (C) 1999, Linus Torvalds - * - */ -#include -#include -#include - -#include - -/* - * Atomically update sem->count. Equivalent to: - * old_val = sem->count.counter; - * new_val = ((old_val >= 0) ? old_val : 0) + incr; - * sem->count.counter = new_val; - * return old_val; - */ -static inline int __sem_update_count(struct semaphore *sem, int incr) -{ - int old_val, new_val; - - asm volatile( - " l %0,0(%3)\n" - "0: ltr %1,%0\n" - " jhe 1f\n" - " lhi %1,0\n" - "1: ar %1,%4\n" - " cs %0,%1,0(%3)\n" - " jl 0b\n" - : "=&d" (old_val), "=&d" (new_val), "=m" (sem->count) - : "a" (&sem->count), "d" (incr), "m" (sem->count) - : "cc"); - return old_val; -} - -/* - * The inline function up() incremented count but the result - * was <= 0. This indicates that some process is waiting on - * the semaphore. The semaphore is free and we'll wake the - * first sleeping process, so we set count to 1 unless some - * other cpu has called up in the meantime in which case - * we just increment count by 1. - */ -void __up(struct semaphore *sem) -{ - __sem_update_count(sem, 1); - wake_up(&sem->wait); -} - -/* - * The inline function down() decremented count and the result - * was < 0. The wait loop will atomically test and update the - * semaphore counter following the rules: - * count > 0: decrement count, wake up queue and exit. - * count <= 0: set count to -1, go to sleep. - */ -void __sched __down(struct semaphore * sem) -{ - struct task_struct *tsk = current; - DECLARE_WAITQUEUE(wait, tsk); - - __set_task_state(tsk, TASK_UNINTERRUPTIBLE); - add_wait_queue_exclusive(&sem->wait, &wait); - while (__sem_update_count(sem, -1) <= 0) { - schedule(); - set_task_state(tsk, TASK_UNINTERRUPTIBLE); - } - remove_wait_queue(&sem->wait, &wait); - __set_task_state(tsk, TASK_RUNNING); - wake_up(&sem->wait); -} - -/* - * Same as __down() with an additional test for signals. - * If a signal is pending the count is updated as follows: - * count > 0: wake up queue and exit. - * count <= 0: set count to 0, wake up queue and exit. - */ -int __sched __down_interruptible(struct semaphore * sem) -{ - int retval = 0; - struct task_struct *tsk = current; - DECLARE_WAITQUEUE(wait, tsk); - - __set_task_state(tsk, TASK_INTERRUPTIBLE); - add_wait_queue_exclusive(&sem->wait, &wait); - while (__sem_update_count(sem, -1) <= 0) { - if (signal_pending(current)) { - __sem_update_count(sem, 0); - retval = -EINTR; - break; - } - schedule(); - set_task_state(tsk, TASK_INTERRUPTIBLE); - } - remove_wait_queue(&sem->wait, &wait); - __set_task_state(tsk, TASK_RUNNING); - wake_up(&sem->wait); - return retval; -} - diff --git a/arch/sh/kernel/Makefile_32 b/arch/sh/kernel/Makefile_32 index 62bf373266..4bbdce36b9 100644 --- a/arch/sh/kernel/Makefile_32 +++ b/arch/sh/kernel/Makefile_32 @@ -5,7 +5,7 @@ extra-y := head_32.o init_task.o vmlinux.lds obj-y := debugtraps.o io.o io_generic.o irq.o machvec.o process_32.o \ - ptrace_32.o semaphore.o setup.o signal_32.o sys_sh.o sys_sh32.o \ + ptrace_32.o setup.o signal_32.o sys_sh.o sys_sh32.o \ syscalls_32.o time_32.o topology.o traps.o traps_32.o obj-y += cpu/ timers/ diff --git a/arch/sh/kernel/Makefile_64 b/arch/sh/kernel/Makefile_64 index e01283d49c..6edf53b93d 100644 --- a/arch/sh/kernel/Makefile_64 +++ b/arch/sh/kernel/Makefile_64 @@ -1,7 +1,7 @@ extra-y := head_64.o init_task.o vmlinux.lds obj-y := debugtraps.o io.o io_generic.o irq.o machvec.o process_64.o \ - ptrace_64.o semaphore.o setup.o signal_64.o sys_sh.o sys_sh64.o \ + ptrace_64.o setup.o signal_64.o sys_sh.o sys_sh64.o \ syscalls_64.o time_64.o topology.o traps.o traps_64.o obj-y += cpu/ timers/ diff --git a/arch/sh/kernel/semaphore.c b/arch/sh/kernel/semaphore.c deleted file mode 100644 index 184119eeae..0000000000 --- a/arch/sh/kernel/semaphore.c +++ /dev/null @@ -1,139 +0,0 @@ -/* - * Just taken from alpha implementation. - * This can't work well, perhaps. - */ -/* - * Generic semaphore code. Buyer beware. Do your own - * specific changes in - */ - -#include -#include -#include -#include -#include -#include - -DEFINE_SPINLOCK(semaphore_wake_lock); - -/* - * Semaphores are implemented using a two-way counter: - * The "count" variable is decremented for each process - * that tries to sleep, while the "waking" variable is - * incremented when the "up()" code goes to wake up waiting - * processes. - * - * Notably, the inline "up()" and "down()" functions can - * efficiently test if they need to do any extra work (up - * needs to do something only if count was negative before - * the increment operation. - * - * waking_non_zero() (from asm/semaphore.h) must execute - * atomically. - * - * When __up() is called, the count was negative before - * incrementing it, and we need to wake up somebody. - * - * This routine adds one to the count of processes that need to - * wake up and exit. ALL waiting processes actually wake up but - * only the one that gets to the "waking" field first will gate - * through and acquire the semaphore. The others will go back - * to sleep. - * - * Note that these functions are only called when there is - * contention on the lock, and as such all this is the - * "non-critical" part of the whole semaphore business. The - * critical part is the inline stuff in - * where we want to avoid any extra jumps and calls. - */ -void __up(struct semaphore *sem) -{ - wake_one_more(sem); - wake_up(&sem->wait); -} - -/* - * Perform the "down" function. Return zero for semaphore acquired, - * return negative for signalled out of the function. - * - * If called from __down, the return is ignored and the wait loop is - * not interruptible. This means that a task waiting on a semaphore - * using "down()" cannot be killed until someone does an "up()" on - * the semaphore. - * - * If called from __down_interruptible, the return value gets checked - * upon return. If the return value is negative then the task continues - * with the negative value in the return register (it can be tested by - * the caller). - * - * Either form may be used in conjunction with "up()". - * - */ - -#define DOWN_VAR \ - struct task_struct *tsk = current; \ - wait_queue_t wait; \ - init_waitqueue_entry(&wait, tsk); - -#define DOWN_HEAD(task_state) \ - \ - \ - tsk->state = (task_state); \ - add_wait_queue(&sem->wait, &wait); \ - \ - /* \ - * Ok, we're set up. sem->count is known to be less than zero \ - * so we must wait. \ - * \ - * We can let go the lock for purposes of waiting. \ - * We re-acquire it after awaking so as to protect \ - * all semaphore operations. \ - * \ - * If "up()" is called before we call waking_non_zero() then \ - * we will catch it right away. If it is called later then \ - * we will have to go through a wakeup cycle to catch it. \ - * \ - * Multiple waiters contend for the semaphore lock to see \ - * who gets to gate through and who has to wait some more. \ - */ \ - for (;;) { - -#define DOWN_TAIL(task_state) \ - tsk->state = (task_state); \ - } \ - tsk->state = TASK_RUNNING; \ - remove_wait_queue(&sem->wait, &wait); - -void __sched __down(struct semaphore * sem) -{ - DOWN_VAR - DOWN_HEAD(TASK_UNINTERRUPTIBLE) - if (waking_non_zero(sem)) - break; - schedule(); - DOWN_TAIL(TASK_UNINTERRUPTIBLE) -} - -int __sched __down_interruptible(struct semaphore * sem) -{ - int ret = 0; - DOWN_VAR - DOWN_HEAD(TASK_INTERRUPTIBLE) - - ret = waking_non_zero_interruptible(sem, tsk); - if (ret) - { - if (ret == 1) - /* ret != 0 only if we get interrupted -arca */ - ret = 0; - break; - } - schedule(); - DOWN_TAIL(TASK_INTERRUPTIBLE) - return ret; -} - -int __down_trylock(struct semaphore * sem) -{ - return waking_non_zero_trylock(sem); -} diff --git a/arch/sh/kernel/sh_ksyms_32.c b/arch/sh/kernel/sh_ksyms_32.c index 45bb333fd9..6d405462ce 100644 --- a/arch/sh/kernel/sh_ksyms_32.c +++ b/arch/sh/kernel/sh_ksyms_32.c @@ -9,7 +9,6 @@ #include #include #include -#include #include #include #include @@ -48,12 +47,6 @@ EXPORT_SYMBOL(__copy_user); EXPORT_SYMBOL(get_vm_area); #endif -/* semaphore exports */ -EXPORT_SYMBOL(__up); -EXPORT_SYMBOL(__down); -EXPORT_SYMBOL(__down_interruptible); -EXPORT_SYMBOL(__down_trylock); - EXPORT_SYMBOL(__udelay); EXPORT_SYMBOL(__ndelay); EXPORT_SYMBOL(__const_udelay); diff --git a/arch/sh/kernel/sh_ksyms_64.c b/arch/sh/kernel/sh_ksyms_64.c index b6410ce4bd..a310c9707f 100644 --- a/arch/sh/kernel/sh_ksyms_64.c +++ b/arch/sh/kernel/sh_ksyms_64.c @@ -16,7 +16,6 @@ #include #include #include -#include #include #include #include @@ -37,9 +36,6 @@ EXPORT_SYMBOL(csum_partial_copy_nocheck); EXPORT_SYMBOL(screen_info); #endif -EXPORT_SYMBOL(__down); -EXPORT_SYMBOL(__down_trylock); -EXPORT_SYMBOL(__up); EXPORT_SYMBOL(__put_user_asm_l); EXPORT_SYMBOL(__get_user_asm_l); EXPORT_SYMBOL(copy_page); diff --git a/arch/sparc/kernel/Makefile b/arch/sparc/kernel/Makefile index bf1b15d3f6..2712bb166f 100644 --- a/arch/sparc/kernel/Makefile +++ b/arch/sparc/kernel/Makefile @@ -12,7 +12,7 @@ obj-y := entry.o wof.o wuf.o etrap.o rtrap.o traps.o $(IRQ_OBJS) \ sys_sparc.o sunos_asm.o systbls.o \ time.o windows.o cpu.o devices.o sclow.o \ tadpole.o tick14.o ptrace.o sys_solaris.o \ - unaligned.o una_asm.o muldiv.o semaphore.o \ + unaligned.o una_asm.o muldiv.o \ prom.o of_device.o devres.o devres-y = ../../../kernel/irq/devres.o diff --git a/arch/sparc/kernel/semaphore.c b/arch/sparc/kernel/semaphore.c deleted file mode 100644 index 0c37c1a7cd..0000000000 --- a/arch/sparc/kernel/semaphore.c +++ /dev/null @@ -1,155 +0,0 @@ -/* $Id: semaphore.c,v 1.7 2001/04/18 21:06:05 davem Exp $ */ - -/* sparc32 semaphore implementation, based on i386 version */ - -#include -#include -#include - -#include - -/* - * Semaphores are implemented using a two-way counter: - * The "count" variable is decremented for each process - * that tries to acquire the semaphore, while the "sleeping" - * variable is a count of such acquires. - * - * Notably, the inline "up()" and "down()" functions can - * efficiently test if they need to do any extra work (up - * needs to do something only if count was negative before - * the increment operation. - * - * "sleeping" and the contention routine ordering is - * protected by the semaphore spinlock. - * - * Note that these functions are only called when there is - * contention on the lock, and as such all this is the - * "non-critical" part of the whole semaphore business. The - * critical part is the inline stuff in - * where we want to avoid any extra jumps and calls. - */ - -/* - * Logic: - * - only on a boundary condition do we need to care. When we go - * from a negative count to a non-negative, we wake people up. - * - when we go from a non-negative count to a negative do we - * (a) synchronize with the "sleeper" count and (b) make sure - * that we're on the wakeup list before we synchronize so that - * we cannot lose wakeup events. - */ - -void __up(struct semaphore *sem) -{ - wake_up(&sem->wait); -} - -static DEFINE_SPINLOCK(semaphore_lock); - -void __sched __down(struct semaphore * sem) -{ - struct task_struct *tsk = current; - DECLARE_WAITQUEUE(wait, tsk); - tsk->state = TASK_UNINTERRUPTIBLE; - add_wait_queue_exclusive(&sem->wait, &wait); - - spin_lock_irq(&semaphore_lock); - sem->sleepers++; - for (;;) { - int sleepers = sem->sleepers; - - /* - * Add "everybody else" into it. They aren't - * playing, because we own the spinlock. - */ - if (!atomic24_add_negative(sleepers - 1, &sem->count)) { - sem->sleepers = 0; - break; - } - sem->sleepers = 1; /* us - see -1 above */ - spin_unlock_irq(&semaphore_lock); - - schedule(); - tsk->state = TASK_UNINTERRUPTIBLE; - spin_lock_irq(&semaphore_lock); - } - spin_unlock_irq(&semaphore_lock); - remove_wait_queue(&sem->wait, &wait); - tsk->state = TASK_RUNNING; - wake_up(&sem->wait); -} - -int __sched __down_interruptible(struct semaphore * sem) -{ - int retval = 0; - struct task_struct *tsk = current; - DECLARE_WAITQUEUE(wait, tsk); - tsk->state = TASK_INTERRUPTIBLE; - add_wait_queue_exclusive(&sem->wait, &wait); - - spin_lock_irq(&semaphore_lock); - sem->sleepers ++; - for (;;) { - int sleepers = sem->sleepers; - - /* - * With signals pending, this turns into - * the trylock failure case - we won't be - * sleeping, and we* can't get the lock as - * it has contention. Just correct the count - * and exit. - */ - if (signal_pending(current)) { - retval = -EINTR; - sem->sleepers = 0; - atomic24_add(sleepers, &sem->count); - break; - } - - /* - * Add "everybody else" into it. They aren't - * playing, because we own the spinlock. The - * "-1" is because we're still hoping to get - * the lock. - */ - if (!atomic24_add_negative(sleepers - 1, &sem->count)) { - sem->sleepers = 0; - break; - } - sem->sleepers = 1; /* us - see -1 above */ - spin_unlock_irq(&semaphore_lock); - - schedule(); - tsk->state = TASK_INTERRUPTIBLE; - spin_lock_irq(&semaphore_lock); - } - spin_unlock_irq(&semaphore_lock); - tsk->state = TASK_RUNNING; - remove_wait_queue(&sem->wait, &wait); - wake_up(&sem->wait); - return retval; -} - -/* - * Trylock failed - make sure we correct for - * having decremented the count. - */ -int __down_trylock(struct semaphore * sem) -{ - int sleepers; - unsigned long flags; - - spin_lock_irqsave(&semaphore_lock, flags); - sleepers = sem->sleepers + 1; - sem->sleepers = 0; - - /* - * Add "everybody else" and us into it. They aren't - * playing, because we own the spinlock. - */ - if (!atomic24_add_negative(sleepers, &sem->count)) - wake_up(&sem->wait); - - spin_unlock_irqrestore(&semaphore_lock, flags); - return 1; -} diff --git a/arch/sparc/kernel/sparc_ksyms.c b/arch/sparc/kernel/sparc_ksyms.c index c1025e5516..97b1de0e90 100644 --- a/arch/sparc/kernel/sparc_ksyms.c +++ b/arch/sparc/kernel/sparc_ksyms.c @@ -107,11 +107,6 @@ EXPORT_SYMBOL(___rw_read_try); EXPORT_SYMBOL(___rw_read_exit); EXPORT_SYMBOL(___rw_write_enter); #endif -/* semaphores */ -EXPORT_SYMBOL(__up); -EXPORT_SYMBOL(__down); -EXPORT_SYMBOL(__down_trylock); -EXPORT_SYMBOL(__down_interruptible); EXPORT_SYMBOL(sparc_valid_addr_bitmap); EXPORT_SYMBOL(phys_base); diff --git a/arch/sparc64/kernel/Makefile b/arch/sparc64/kernel/Makefile index 1bf5b187de..459462e80a 100644 --- a/arch/sparc64/kernel/Makefile +++ b/arch/sparc64/kernel/Makefile @@ -10,7 +10,7 @@ extra-y := head.o init_task.o vmlinux.lds obj-y := process.o setup.o cpu.o idprom.o \ traps.o auxio.o una_asm.o sysfs.o iommu.o \ irq.o ptrace.o time.o sys_sparc.o signal.o \ - unaligned.o central.o pci.o starfire.o semaphore.o \ + unaligned.o central.o pci.o starfire.o \ power.o sbus.o sparc64_ksyms.o chmc.o \ visemul.o prom.o of_device.o hvapi.o sstate.o mdesc.o diff --git a/arch/sparc64/kernel/semaphore.c b/arch/sparc64/kernel/semaphore.c deleted file mode 100644 index 9974a68995..0000000000 --- a/arch/sparc64/kernel/semaphore.c +++ /dev/null @@ -1,254 +0,0 @@ -/* semaphore.c: Sparc64 semaphore implementation. - * - * This is basically the PPC semaphore scheme ported to use - * the sparc64 atomic instructions, so see the PPC code for - * credits. - */ - -#include -#include -#include - -/* - * Atomically update sem->count. - * This does the equivalent of the following: - * - * old_count = sem->count; - * tmp = MAX(old_count, 0) + incr; - * sem->count = tmp; - * return old_count; - */ -static inline int __sem_update_count(struct semaphore *sem, int incr) -{ - int old_count, tmp; - - __asm__ __volatile__("\n" -" ! __sem_update_count old_count(%0) tmp(%1) incr(%4) &sem->count(%3)\n" -"1: ldsw [%3], %0\n" -" mov %0, %1\n" -" cmp %0, 0\n" -" movl %%icc, 0, %1\n" -" add %1, %4, %1\n" -" cas [%3], %0, %1\n" -" cmp %0, %1\n" -" membar #StoreLoad | #StoreStore\n" -" bne,pn %%icc, 1b\n" -" nop\n" - : "=&r" (old_count), "=&r" (tmp), "=m" (sem->count) - : "r" (&sem->count), "r" (incr), "m" (sem->count) - : "cc"); - - return old_count; -} - -static void __up(struct semaphore *sem) -{ - __sem_update_count(sem, 1); - wake_up(&sem->wait); -} - -void up(struct semaphore *sem) -{ - /* This atomically does: - * old_val = sem->count; - * new_val = sem->count + 1; - * sem->count = new_val; - * if (old_val < 0) - * __up(sem); - * - * The (old_val < 0) test is equivalent to - * the more straightforward (new_val <= 0), - * but it is easier to test the former because - * of how the CAS instruction works. - */ - - __asm__ __volatile__("\n" -" ! up sem(%0)\n" -" membar #StoreLoad | #LoadLoad\n" -"1: lduw [%0], %%g1\n" -" add %%g1, 1, %%g7\n" -" cas [%0], %%g1, %%g7\n" -" cmp %%g1, %%g7\n" -" bne,pn %%icc, 1b\n" -" addcc %%g7, 1, %%g0\n" -" membar #StoreLoad | #StoreStore\n" -" ble,pn %%icc, 3f\n" -" nop\n" -"2:\n" -" .subsection 2\n" -"3: mov %0, %%g1\n" -" save %%sp, -160, %%sp\n" -" call %1\n" -" mov %%g1, %%o0\n" -" ba,pt %%xcc, 2b\n" -" restore\n" -" .previous\n" - : : "r" (sem), "i" (__up) - : "g1", "g2", "g3", "g7", "memory", "cc"); -} - -static void __sched __down(struct semaphore * sem) -{ - struct task_struct *tsk = current; - DECLARE_WAITQUEUE(wait, tsk); - - tsk->state = TASK_UNINTERRUPTIBLE; - add_wait_queue_exclusive(&sem->wait, &wait); - - while (__sem_update_count(sem, -1) <= 0) { - schedule(); - tsk->state = TASK_UNINTERRUPTIBLE; - } - remove_wait_queue(&sem->wait, &wait); - tsk->state = TASK_RUNNING; - - wake_up(&sem->wait); -} - -void __sched down(struct semaphore *sem) -{ - might_sleep(); - /* This atomically does: - * old_val = sem->count; - * new_val = sem->count - 1; - * sem->count = new_val; - * if (old_val < 1) - * __down(sem); - * - * The (old_val < 1) test is equivalent to - * the more straightforward (new_val < 0), - * but it is easier to test the former because - * of how the CAS instruction works. - */ - - __asm__ __volatile__("\n" -" ! down sem(%0)\n" -"1: lduw [%0], %%g1\n" -" sub %%g1, 1, %%g7\n" -" cas [%0], %%g1, %%g7\n" -" cmp %%g1, %%g7\n" -" bne,pn %%icc, 1b\n" -" cmp %%g7, 1\n" -" membar #StoreLoad | #StoreStore\n" -" bl,pn %%icc, 3f\n" -" nop\n" -"2:\n" -" .subsection 2\n" -"3: mov %0, %%g1\n" -" save %%sp, -160, %%sp\n" -" call %1\n" -" mov %%g1, %%o0\n" -" ba,pt %%xcc, 2b\n" -" restore\n" -" .previous\n" - : : "r" (sem), "i" (__down) - : "g1", "g2", "g3", "g7", "memory", "cc"); -} - -int down_trylock(struct semaphore *sem) -{ - int ret; - - /* This atomically does: - * old_val = sem->count; - * new_val = sem->count - 1; - * if (old_val < 1) { - * ret = 1; - * } else { - * sem->count = new_val; - * ret = 0; - * } - * - * The (old_val < 1) test is equivalent to - * the more straightforward (new_val < 0), - * but it is easier to test the former because - * of how the CAS instruction works. - */ - - __asm__ __volatile__("\n" -" ! down_trylock sem(%1) ret(%0)\n" -"1: lduw [%1], %%g1\n" -" sub %%g1, 1, %%g7\n" -" cmp %%g1, 1\n" -" bl,pn %%icc, 2f\n" -" mov 1, %0\n" -" cas [%1], %%g1, %%g7\n" -" cmp %%g1, %%g7\n" -" bne,pn %%icc, 1b\n" -" mov 0, %0\n" -" membar #StoreLoad | #StoreStore\n" -"2:\n" - : "=&r" (ret) - : "r" (sem) - : "g1", "g7", "memory", "cc"); - - return ret; -} - -static int __sched __down_interruptible(struct semaphore * sem) -{ - int retval = 0; - struct task_struct *tsk = current; - DECLARE_WAITQUEUE(wait, tsk); - - tsk->state = TASK_INTERRUPTIBLE; - add_wait_queue_exclusive(&sem->wait, &wait); - - while (__sem_update_count(sem, -1) <= 0) { - if (signal_pending(current)) { - __sem_update_count(sem, 0); - retval = -EINTR; - break; - } - schedule(); - tsk->state = TASK_INTERRUPTIBLE; - } - tsk->state = TASK_RUNNING; - remove_wait_queue(&sem->wait, &wait); - wake_up(&sem->wait); - return retval; -} - -int __sched down_interruptible(struct semaphore *sem) -{ - int ret = 0; - - might_sleep(); - /* This atomically does: - * old_val = sem->count; - * new_val = sem->count - 1; - * sem->count = new_val; - * if (old_val < 1) - * ret = __down_interruptible(sem); - * - * The (old_val < 1) test is equivalent to - * the more straightforward (new_val < 0), - * but it is easier to test the former because - * of how the CAS instruction works. - */ - - __asm__ __volatile__("\n" -" ! down_interruptible sem(%2) ret(%0)\n" -"1: lduw [%2], %%g1\n" -" sub %%g1, 1, %%g7\n" -" cas [%2], %%g1, %%g7\n" -" cmp %%g1, %%g7\n" -" bne,pn %%icc, 1b\n" -" cmp %%g7, 1\n" -" membar #StoreLoad | #StoreStore\n" -" bl,pn %%icc, 3f\n" -" nop\n" -"2:\n" -" .subsection 2\n" -"3: mov %2, %%g1\n" -" save %%sp, -160, %%sp\n" -" call %3\n" -" mov %%g1, %%o0\n" -" ba,pt %%xcc, 2b\n" -" restore\n" -" .previous\n" - : "=r" (ret) - : "0" (ret), "r" (sem), "i" (__down_interruptible) - : "g1", "g2", "g3", "g7", "memory", "cc"); - return ret; -} diff --git a/arch/sparc64/kernel/sparc64_ksyms.c b/arch/sparc64/kernel/sparc64_ksyms.c index 51fa773f38..051b8d9cb9 100644 --- a/arch/sparc64/kernel/sparc64_ksyms.c +++ b/arch/sparc64/kernel/sparc64_ksyms.c @@ -130,12 +130,6 @@ EXPORT_SYMBOL(_mcount); EXPORT_SYMBOL(sparc64_get_clock_tick); -/* semaphores */ -EXPORT_SYMBOL(down); -EXPORT_SYMBOL(down_trylock); -EXPORT_SYMBOL(down_interruptible); -EXPORT_SYMBOL(up); - /* RW semaphores */ EXPORT_SYMBOL(__down_read); EXPORT_SYMBOL(__down_read_trylock); diff --git a/arch/um/Kconfig.i386 b/arch/um/Kconfig.i386 index 3cd8a04d66..e09edfa560 100644 --- a/arch/um/Kconfig.i386 +++ b/arch/um/Kconfig.i386 @@ -19,10 +19,6 @@ config 64BIT bool default n -config SEMAPHORE_SLEEPERS - bool - default y - config 3_LEVEL_PGTABLES bool "Three-level pagetables (EXPERIMENTAL)" default n diff --git a/arch/um/Kconfig.x86_64 b/arch/um/Kconfig.x86_64 index 6533b349f0..3fbe69e359 100644 --- a/arch/um/Kconfig.x86_64 +++ b/arch/um/Kconfig.x86_64 @@ -11,10 +11,6 @@ config RWSEM_GENERIC_SPINLOCK bool default y -config SEMAPHORE_SLEEPERS - bool - default y - config 3_LEVEL_PGTABLES bool default y diff --git a/arch/um/sys-i386/ksyms.c b/arch/um/sys-i386/ksyms.c index 2a1eac1859..bfbefd30db 100644 --- a/arch/um/sys-i386/ksyms.c +++ b/arch/um/sys-i386/ksyms.c @@ -1,17 +1,5 @@ #include "linux/module.h" -#include "linux/in6.h" -#include "linux/rwsem.h" -#include "asm/byteorder.h" -#include "asm/delay.h" -#include "asm/semaphore.h" -#include "asm/uaccess.h" #include "asm/checksum.h" -#include "asm/errno.h" - -EXPORT_SYMBOL(__down_failed); -EXPORT_SYMBOL(__down_failed_interruptible); -EXPORT_SYMBOL(__down_failed_trylock); -EXPORT_SYMBOL(__up_wakeup); /* Networking helper routines. */ EXPORT_SYMBOL(csum_partial); diff --git a/arch/um/sys-ppc/Makefile b/arch/um/sys-ppc/Makefile index 08901526e8..b8bc844fd2 100644 --- a/arch/um/sys-ppc/Makefile +++ b/arch/um/sys-ppc/Makefile @@ -3,7 +3,7 @@ OBJ = built-in.o .S.o: $(CC) $(KBUILD_AFLAGS) -D__ASSEMBLY__ -D__UM_PPC__ -c $< -o $*.o -OBJS = ptrace.o sigcontext.o semaphore.o checksum.o miscthings.o misc.o \ +OBJS = ptrace.o sigcontext.o checksum.o miscthings.o misc.o \ ptrace_user.o sysrq.o EXTRA_AFLAGS := -DCONFIG_PPC32 -I. -I$(srctree)/arch/ppc/kernel @@ -20,10 +20,6 @@ ptrace_user.o: ptrace_user.c sigcontext.o: sigcontext.c $(CC) $(USER_CFLAGS) $(EXTRA_CFLAGS) -c -o $@ $< -semaphore.c: - rm -f $@ - ln -s $(srctree)/arch/ppc/kernel/$@ $@ - checksum.S: rm -f $@ ln -s $(srctree)/arch/ppc/lib/$@ $@ @@ -66,4 +62,4 @@ misc.o: misc.S ppc_defs.h $(CC) $(EXTRA_AFLAGS) $(KBUILD_AFLAGS) -D__ASSEMBLY__ -D__UM_PPC__ -c $< -o $*.o rm -f asm -clean-files := $(OBJS) ppc_defs.h checksum.S semaphore.c mk_defs.c +clean-files := $(OBJS) ppc_defs.h checksum.S mk_defs.c diff --git a/arch/um/sys-x86_64/ksyms.c b/arch/um/sys-x86_64/ksyms.c index 12c593607c..4d7d1a812d 100644 --- a/arch/um/sys-x86_64/ksyms.c +++ b/arch/um/sys-x86_64/ksyms.c @@ -1,16 +1,5 @@ #include "linux/module.h" -#include "linux/in6.h" -#include "linux/rwsem.h" -#include "asm/byteorder.h" -#include "asm/semaphore.h" -#include "asm/uaccess.h" -#include "asm/checksum.h" -#include "asm/errno.h" - -EXPORT_SYMBOL(__down_failed); -EXPORT_SYMBOL(__down_failed_interruptible); -EXPORT_SYMBOL(__down_failed_trylock); -EXPORT_SYMBOL(__up_wakeup); +#include "asm/string.h" /*XXX: we need them because they would be exported by x86_64 */ EXPORT_SYMBOL(__memcpy); diff --git a/arch/v850/kernel/Makefile b/arch/v850/kernel/Makefile index 3930482bdd..da5889c535 100644 --- a/arch/v850/kernel/Makefile +++ b/arch/v850/kernel/Makefile @@ -11,7 +11,7 @@ extra-y := head.o init_task.o vmlinux.lds -obj-y += intv.o entry.o process.o syscalls.o time.o semaphore.o setup.o \ +obj-y += intv.o entry.o process.o syscalls.o time.o setup.o \ signal.o irq.o mach.o ptrace.o bug.o obj-$(CONFIG_MODULES) += module.o v850_ksyms.o # chip-specific code diff --git a/arch/v850/kernel/semaphore.c b/arch/v850/kernel/semaphore.c deleted file mode 100644 index fc89fd661c..0000000000 --- a/arch/v850/kernel/semaphore.c +++ /dev/null @@ -1,166 +0,0 @@ -/* - * arch/v850/kernel/semaphore.c -- Semaphore support - * - * Copyright (C) 1998-2000 IBM Corporation - * Copyright (C) 1999 Linus Torvalds - * - * This file is subject to the terms and conditions of the GNU General - * Public License. See the file COPYING in the main directory of this - * archive for more details. - * - * This file is a copy of the s390 version, arch/s390/kernel/semaphore.c - * Author(s): Martin Schwidefsky - * which was derived from the i386 version, linux/arch/i386/kernel/semaphore.c - */ - -#include -#include -#include - -#include - -/* - * Semaphores are implemented using a two-way counter: - * The "count" variable is decremented for each process - * that tries to acquire the semaphore, while the "sleeping" - * variable is a count of such acquires. - * - * Notably, the inline "up()" and "down()" functions can - * efficiently test if they need to do any extra work (up - * needs to do something only if count was negative before - * the increment operation. - * - * "sleeping" and the contention routine ordering is - * protected by the semaphore spinlock. - * - * Note that these functions are only called when there is - * contention on the lock, and as such all this is the - * "non-critical" part of the whole semaphore business. The - * critical part is the inline stuff in - * where we want to avoid any extra jumps and calls. - */ - -/* - * Logic: - * - only on a boundary condition do we need to care. When we go - * from a negative count to a non-negative, we wake people up. - * - when we go from a non-negative count to a negative do we - * (a) synchronize with the "sleeper" count and (b) make sure - * that we're on the wakeup list before we synchronize so that - * we cannot lose wakeup events. - */ - -void __up(struct semaphore *sem) -{ - wake_up(&sem->wait); -} - -static DEFINE_SPINLOCK(semaphore_lock); - -void __sched __down(struct semaphore * sem) -{ - struct task_struct *tsk = current; - DECLARE_WAITQUEUE(wait, tsk); - tsk->state = TASK_UNINTERRUPTIBLE; - add_wait_queue_exclusive(&sem->wait, &wait); - - spin_lock_irq(&semaphore_lock); - sem->sleepers++; - for (;;) { - int sleepers = sem->sleepers; - - /* - * Add "everybody else" into it. They aren't - * playing, because we own the spinlock. - */ - if (!atomic_add_negative(sleepers - 1, &sem->count)) { - sem->sleepers = 0; - break; - } - sem->sleepers = 1; /* us - see -1 above */ - spin_unlock_irq(&semaphore_lock); - - schedule(); - tsk->state = TASK_UNINTERRUPTIBLE; - spin_lock_irq(&semaphore_lock); - } - spin_unlock_irq(&semaphore_lock); - remove_wait_queue(&sem->wait, &wait); - tsk->state = TASK_RUNNING; - wake_up(&sem->wait); -} - -int __sched __down_interruptible(struct semaphore * sem) -{ - int retval = 0; - struct task_struct *tsk = current; - DECLARE_WAITQUEUE(wait, tsk); - tsk->state = TASK_INTERRUPTIBLE; - add_wait_queue_exclusive(&sem->wait, &wait); - - spin_lock_irq(&semaphore_lock); - sem->sleepers ++; - for (;;) { - int sleepers = sem->sleepers; - - /* - * With signals pending, this turns into - * the trylock failure case - we won't be - * sleeping, and we* can't get the lock as - * it has contention. Just correct the count - * and exit. - */ - if (signal_pending(current)) { - retval = -EINTR; - sem->sleepers = 0; - atomic_add(sleepers, &sem->count); - break; - } - - /* - * Add "everybody else" into it. They aren't - * playing, because we own the spinlock. The - * "-1" is because we're still hoping to get - * the lock. - */ - if (!atomic_add_negative(sleepers - 1, &sem->count)) { - sem->sleepers = 0; - break; - } - sem->sleepers = 1; /* us - see -1 above */ - spin_unlock_irq(&semaphore_lock); - - schedule(); - tsk->state = TASK_INTERRUPTIBLE; - spin_lock_irq(&semaphore_lock); - } - spin_unlock_irq(&semaphore_lock); - tsk->state = TASK_RUNNING; - remove_wait_queue(&sem->wait, &wait); - wake_up(&sem->wait); - return retval; -} - -/* - * Trylock failed - make sure we correct for - * having decremented the count. - */ -int __down_trylock(struct semaphore * sem) -{ - unsigned long flags; - int sleepers; - - spin_lock_irqsave(&semaphore_lock, flags); - sleepers = sem->sleepers + 1; - sem->sleepers = 0; - - /* - * Add "everybody else" and us into it. They aren't - * playing, because we own the spinlock. - */ - if (!atomic_add_negative(sleepers, &sem->count)) - wake_up(&sem->wait); - - spin_unlock_irqrestore(&semaphore_lock, flags); - return 1; -} diff --git a/arch/v850/kernel/v850_ksyms.c b/arch/v850/kernel/v850_ksyms.c index 93575fdc87..8d386a5dbc 100644 --- a/arch/v850/kernel/v850_ksyms.c +++ b/arch/v850/kernel/v850_ksyms.c @@ -11,7 +11,6 @@ #include #include #include -#include #include #include @@ -34,12 +33,6 @@ EXPORT_SYMBOL (memset); EXPORT_SYMBOL (memcpy); EXPORT_SYMBOL (memmove); -/* semaphores */ -EXPORT_SYMBOL (__down); -EXPORT_SYMBOL (__down_interruptible); -EXPORT_SYMBOL (__down_trylock); -EXPORT_SYMBOL (__up); - /* * libgcc functions - functions that are used internally by the * compiler... (prototypes are not correct though, but that diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 6c70fed0f9..e4b38861ea 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -53,9 +53,6 @@ config STACKTRACE_SUPPORT config HAVE_LATENCYTOP_SUPPORT def_bool y -config SEMAPHORE_SLEEPERS - def_bool y - config FAST_CMPXCHG_LOCAL bool default y diff --git a/arch/x86/kernel/i386_ksyms_32.c b/arch/x86/kernel/i386_ksyms_32.c index 061627806a..deb43785e9 100644 --- a/arch/x86/kernel/i386_ksyms_32.c +++ b/arch/x86/kernel/i386_ksyms_32.c @@ -1,13 +1,8 @@ #include -#include #include #include #include -EXPORT_SYMBOL(__down_failed); -EXPORT_SYMBOL(__down_failed_interruptible); -EXPORT_SYMBOL(__down_failed_trylock); -EXPORT_SYMBOL(__up_wakeup); /* Networking helper routines. */ EXPORT_SYMBOL(csum_partial_copy_generic); diff --git a/arch/x86/kernel/x8664_ksyms_64.c b/arch/x86/kernel/x8664_ksyms_64.c index a66e9c1a05..95a993e181 100644 --- a/arch/x86/kernel/x8664_ksyms_64.c +++ b/arch/x86/kernel/x8664_ksyms_64.c @@ -4,7 +4,6 @@ #include #include -#include #include #include #include @@ -12,11 +11,6 @@ EXPORT_SYMBOL(kernel_thread); -EXPORT_SYMBOL(__down_failed); -EXPORT_SYMBOL(__down_failed_interruptible); -EXPORT_SYMBOL(__down_failed_trylock); -EXPORT_SYMBOL(__up_wakeup); - EXPORT_SYMBOL(__get_user_1); EXPORT_SYMBOL(__get_user_2); EXPORT_SYMBOL(__get_user_4); diff --git a/arch/x86/lib/semaphore_32.S b/arch/x86/lib/semaphore_32.S index 3899bd37fd..648fe47417 100644 --- a/arch/x86/lib/semaphore_32.S +++ b/arch/x86/lib/semaphore_32.S @@ -30,89 +30,6 @@ * value or just clobbered.. */ .section .sched.text, "ax" -ENTRY(__down_failed) - CFI_STARTPROC - FRAME - pushl %edx - CFI_ADJUST_CFA_OFFSET 4 - CFI_REL_OFFSET edx,0 - pushl %ecx - CFI_ADJUST_CFA_OFFSET 4 - CFI_REL_OFFSET ecx,0 - call __down - popl %ecx - CFI_ADJUST_CFA_OFFSET -4 - CFI_RESTORE ecx - popl %edx - CFI_ADJUST_CFA_OFFSET -4 - CFI_RESTORE edx - ENDFRAME - ret - CFI_ENDPROC - ENDPROC(__down_failed) - -ENTRY(__down_failed_interruptible) - CFI_STARTPROC - FRAME - pushl %edx - CFI_ADJUST_CFA_OFFSET 4 - CFI_REL_OFFSET edx,0 - pushl %ecx - CFI_ADJUST_CFA_OFFSET 4 - CFI_REL_OFFSET ecx,0 - call __down_interruptible - popl %ecx - CFI_ADJUST_CFA_OFFSET -4 - CFI_RESTORE ecx - popl %edx - CFI_ADJUST_CFA_OFFSET -4 - CFI_RESTORE edx - ENDFRAME - ret - CFI_ENDPROC - ENDPROC(__down_failed_interruptible) - -ENTRY(__down_failed_trylock) - CFI_STARTPROC - FRAME - pushl %edx - CFI_ADJUST_CFA_OFFSET 4 - CFI_REL_OFFSET edx,0 - pushl %ecx - CFI_ADJUST_CFA_OFFSET 4 - CFI_REL_OFFSET ecx,0 - call __down_trylock - popl %ecx - CFI_ADJUST_CFA_OFFSET -4 - CFI_RESTORE ecx - popl %edx - CFI_ADJUST_CFA_OFFSET -4 - CFI_RESTORE edx - ENDFRAME - ret - CFI_ENDPROC - ENDPROC(__down_failed_trylock) - -ENTRY(__up_wakeup) - CFI_STARTPROC - FRAME - pushl %edx - CFI_ADJUST_CFA_OFFSET 4 - CFI_REL_OFFSET edx,0 - pushl %ecx - CFI_ADJUST_CFA_OFFSET 4 - CFI_REL_OFFSET ecx,0 - call __up - popl %ecx - CFI_ADJUST_CFA_OFFSET -4 - CFI_RESTORE ecx - popl %edx - CFI_ADJUST_CFA_OFFSET -4 - CFI_RESTORE edx - ENDFRAME - ret - CFI_ENDPROC - ENDPROC(__up_wakeup) /* * rw spinlock fallbacks diff --git a/arch/x86/lib/thunk_64.S b/arch/x86/lib/thunk_64.S index 8b92d428ab..e009251d4e 100644 --- a/arch/x86/lib/thunk_64.S +++ b/arch/x86/lib/thunk_64.S @@ -41,11 +41,6 @@ thunk rwsem_downgrade_thunk,rwsem_downgrade_wake #endif - thunk __down_failed,__down - thunk_retrax __down_failed_interruptible,__down_interruptible - thunk_retrax __down_failed_trylock,__down_trylock - thunk __up_wakeup,__up - #ifdef CONFIG_TRACE_IRQFLAGS thunk trace_hardirqs_on_thunk,trace_hardirqs_on thunk trace_hardirqs_off_thunk,trace_hardirqs_off diff --git a/arch/xtensa/kernel/Makefile b/arch/xtensa/kernel/Makefile index f582d6a24e..7419dbccf0 100644 --- a/arch/xtensa/kernel/Makefile +++ b/arch/xtensa/kernel/Makefile @@ -5,7 +5,7 @@ extra-y := head.o vmlinux.lds -obj-y := align.o entry.o irq.o coprocessor.o process.o ptrace.o semaphore.o \ +obj-y := align.o entry.o irq.o coprocessor.o process.o ptrace.o \ setup.o signal.o syscall.o time.o traps.o vectors.o platform.o \ pci-dma.o init_task.o io.o diff --git a/arch/xtensa/kernel/semaphore.c b/arch/xtensa/kernel/semaphore.c deleted file mode 100644 index 995c6410ae..0000000000 --- a/arch/xtensa/kernel/semaphore.c +++ /dev/null @@ -1,226 +0,0 @@ -/* - * arch/xtensa/kernel/semaphore.c - * - * Generic semaphore code. Buyer beware. Do your own specific changes - * in - * - * This file is subject to the terms and conditions of the GNU General Public - * License. See the file "COPYING" in the main directory of this archive - * for more details. - * - * Copyright (C) 2001 - 2005 Tensilica Inc. - * - * Joe Taylor - * Chris Zankel - * Marc Gauthier - * Kevin Chea - */ - -#include -#include -#include -#include -#include - -/* - * These two _must_ execute atomically wrt each other. - */ - -static __inline__ void wake_one_more(struct semaphore * sem) -{ - atomic_inc((atomic_t *)&sem->sleepers); -} - -static __inline__ int waking_non_zero(struct semaphore *sem) -{ - unsigned long flags; - int ret = 0; - - spin_lock_irqsave(&semaphore_wake_lock, flags); - if (sem->sleepers > 0) { - sem->sleepers--; - ret = 1; - } - spin_unlock_irqrestore(&semaphore_wake_lock, flags); - return ret; -} - -/* - * waking_non_zero_interruptible: - * 1 got the lock - * 0 go to sleep - * -EINTR interrupted - * - * We must undo the sem->count down_interruptible() increment while we are - * protected by the spinlock in order to make atomic this atomic_inc() with the - * atomic_read() in wake_one_more(), otherwise we can race. -arca - */ - -static __inline__ int waking_non_zero_interruptible(struct semaphore *sem, - struct task_struct *tsk) -{ - unsigned long flags; - int ret = 0; - - spin_lock_irqsave(&semaphore_wake_lock, flags); - if (sem->sleepers > 0) { - sem->sleepers--; - ret = 1; - } else if (signal_pending(tsk)) { - atomic_inc(&sem->count); - ret = -EINTR; - } - spin_unlock_irqrestore(&semaphore_wake_lock, flags); - return ret; -} - -/* - * waking_non_zero_trylock: - * 1 failed to lock - * 0 got the lock - * - * We must undo the sem->count down_trylock() increment while we are - * protected by the spinlock in order to make atomic this atomic_inc() with the - * atomic_read() in wake_one_more(), otherwise we can race. -arca - */ - -static __inline__ int waking_non_zero_trylock(struct semaphore *sem) -{ - unsigned long flags; - int ret = 1; - - spin_lock_irqsave(&semaphore_wake_lock, flags); - if (sem->sleepers <= 0) - atomic_inc(&sem->count); - else { - sem->sleepers--; - ret = 0; - } - spin_unlock_irqrestore(&semaphore_wake_lock, flags); - return ret; -} - -DEFINE_SPINLOCK(semaphore_wake_lock); - -/* - * Semaphores are implemented using a two-way counter: - * The "count" variable is decremented for each process - * that tries to sleep, while the "waking" variable is - * incremented when the "up()" code goes to wake up waiting - * processes. - * - * Notably, the inline "up()" and "down()" functions can - * efficiently test if they need to do any extra work (up - * needs to do something only if count was negative before - * the increment operation. - * - * waking_non_zero() (from asm/semaphore.h) must execute - * atomically. - * - * When __up() is called, the count was negative before - * incrementing it, and we need to wake up somebody. - * - * This routine adds one to the count of processes that need to - * wake up and exit. ALL waiting processes actually wake up but - * only the one that gets to the "waking" field first will gate - * through and acquire the semaphore. The others will go back - * to sleep. - * - * Note that these functions are only called when there is - * contention on the lock, and as such all this is the - * "non-critical" part of the whole semaphore business. The - * critical part is the inline stuff in - * where we want to avoid any extra jumps and calls. - */ - -void __up(struct semaphore *sem) -{ - wake_one_more(sem); - wake_up(&sem->wait); -} - -/* - * Perform the "down" function. Return zero for semaphore acquired, - * return negative for signalled out of the function. - * - * If called from __down, the return is ignored and the wait loop is - * not interruptible. This means that a task waiting on a semaphore - * using "down()" cannot be killed until someone does an "up()" on - * the semaphore. - * - * If called from __down_interruptible, the return value gets checked - * upon return. If the return value is negative then the task continues - * with the negative value in the return register (it can be tested by - * the caller). - * - * Either form may be used in conjunction with "up()". - * - */ - -#define DOWN_VAR \ - struct task_struct *tsk = current; \ - wait_queue_t wait; \ - init_waitqueue_entry(&wait, tsk); - -#define DOWN_HEAD(task_state) \ - \ - \ - tsk->state = (task_state); \ - add_wait_queue(&sem->wait, &wait); \ - \ - /* \ - * Ok, we're set up. sem->count is known to be less than zero \ - * so we must wait. \ - * \ - * We can let go the lock for purposes of waiting. \ - * We re-acquire it after awaking so as to protect \ - * all semaphore operations. \ - * \ - * If "up()" is called before we call waking_non_zero() then \ - * we will catch it right away. If it is called later then \ - * we will have to go through a wakeup cycle to catch it. \ - * \ - * Multiple waiters contend for the semaphore lock to see \ - * who gets to gate through and who has to wait some more. \ - */ \ - for (;;) { - -#define DOWN_TAIL(task_state) \ - tsk->state = (task_state); \ - } \ - tsk->state = TASK_RUNNING; \ - remove_wait_queue(&sem->wait, &wait); - -void __sched __down(struct semaphore * sem) -{ - DOWN_VAR - DOWN_HEAD(TASK_UNINTERRUPTIBLE) - if (waking_non_zero(sem)) - break; - schedule(); - DOWN_TAIL(TASK_UNINTERRUPTIBLE) -} - -int __sched __down_interruptible(struct semaphore * sem) -{ - int ret = 0; - DOWN_VAR - DOWN_HEAD(TASK_INTERRUPTIBLE) - - ret = waking_non_zero_interruptible(sem, tsk); - if (ret) - { - if (ret == 1) - /* ret != 0 only if we get interrupted -arca */ - ret = 0; - break; - } - schedule(); - DOWN_TAIL(TASK_INTERRUPTIBLE) - return ret; -} - -int __down_trylock(struct semaphore * sem) -{ - return waking_non_zero_trylock(sem); -} diff --git a/arch/xtensa/kernel/xtensa_ksyms.c b/arch/xtensa/kernel/xtensa_ksyms.c index 60dbdb43fb..6e52cdd616 100644 --- a/arch/xtensa/kernel/xtensa_ksyms.c +++ b/arch/xtensa/kernel/xtensa_ksyms.c @@ -26,7 +26,6 @@ #include #include #include -#include #ifdef CONFIG_BLK_DEV_FD #include #endif @@ -71,14 +70,6 @@ EXPORT_SYMBOL(__umodsi3); EXPORT_SYMBOL(__udivdi3); EXPORT_SYMBOL(__umoddi3); -/* - * Semaphore operations - */ -EXPORT_SYMBOL(__down); -EXPORT_SYMBOL(__down_interruptible); -EXPORT_SYMBOL(__down_trylock); -EXPORT_SYMBOL(__up); - #ifdef CONFIG_NET /* * Networking support diff --git a/include/asm-alpha/semaphore.h b/include/asm-alpha/semaphore.h index f1e9278a9f..d9b2034ed1 100644 --- a/include/asm-alpha/semaphore.h +++ b/include/asm-alpha/semaphore.h @@ -1,149 +1 @@ -#ifndef _ALPHA_SEMAPHORE_H -#define _ALPHA_SEMAPHORE_H - -/* - * SMP- and interrupt-safe semaphores.. - * - * (C) Copyright 1996 Linus Torvalds - * (C) Copyright 1996, 2000 Richard Henderson - */ - -#include -#include -#include -#include -#include -#include - -struct semaphore { - atomic_t count; - wait_queue_head_t wait; -}; - -#define __SEMAPHORE_INITIALIZER(name, n) \ -{ \ - .count = ATOMIC_INIT(n), \ - .wait = __WAIT_QUEUE_HEAD_INITIALIZER((name).wait), \ -} - -#define __DECLARE_SEMAPHORE_GENERIC(name,count) \ - struct semaphore name = __SEMAPHORE_INITIALIZER(name,count) - -#define DECLARE_MUTEX(name) __DECLARE_SEMAPHORE_GENERIC(name,1) - -static inline void sema_init(struct semaphore *sem, int val) -{ - /* - * Logically, - * *sem = (struct semaphore)__SEMAPHORE_INITIALIZER((*sem),val); - * except that gcc produces better initializing by parts yet. - */ - - atomic_set(&sem->count, val); - init_waitqueue_head(&sem->wait); -} - -static inline void init_MUTEX (struct semaphore *sem) -{ - sema_init(sem, 1); -} - -static inline void init_MUTEX_LOCKED (struct semaphore *sem) -{ - sema_init(sem, 0); -} - -extern void down(struct semaphore *); -extern void __down_failed(struct semaphore *); -extern int down_interruptible(struct semaphore *); -extern int __down_failed_interruptible(struct semaphore *); -extern int down_trylock(struct semaphore *); -extern void up(struct semaphore *); -extern void __up_wakeup(struct semaphore *); - -/* - * Hidden out of line code is fun, but extremely messy. Rely on newer - * compilers to do a respectable job with this. The contention cases - * are handled out of line in arch/alpha/kernel/semaphore.c. - */ - -static inline void __down(struct semaphore *sem) -{ - long count; - might_sleep(); - count = atomic_dec_return(&sem->count); - if (unlikely(count < 0)) - __down_failed(sem); -} - -static inline int __down_interruptible(struct semaphore *sem) -{ - long count; - might_sleep(); - count = atomic_dec_return(&sem->count); - if (unlikely(count < 0)) - return __down_failed_interruptible(sem); - return 0; -} - -/* - * down_trylock returns 0 on success, 1 if we failed to get the lock. - */ - -static inline int __down_trylock(struct semaphore *sem) -{ - long ret; - - /* "Equivalent" C: - - do { - ret = ldl_l; - --ret; - if (ret < 0) - break; - ret = stl_c = ret; - } while (ret == 0); - */ - __asm__ __volatile__( - "1: ldl_l %0,%1\n" - " subl %0,1,%0\n" - " blt %0,2f\n" - " stl_c %0,%1\n" - " beq %0,3f\n" - " mb\n" - "2:\n" - ".subsection 2\n" - "3: br 1b\n" - ".previous" - : "=&r" (ret), "=m" (sem->count) - : "m" (sem->count)); - - return ret < 0; -} - -static inline void __up(struct semaphore *sem) -{ - if (unlikely(atomic_inc_return(&sem->count) <= 0)) - __up_wakeup(sem); -} - -#if !defined(CONFIG_DEBUG_SEMAPHORE) -extern inline void down(struct semaphore *sem) -{ - __down(sem); -} -extern inline int down_interruptible(struct semaphore *sem) -{ - return __down_interruptible(sem); -} -extern inline int down_trylock(struct semaphore *sem) -{ - return __down_trylock(sem); -} -extern inline void up(struct semaphore *sem) -{ - __up(sem); -} -#endif - -#endif +#include diff --git a/include/asm-arm/semaphore-helper.h b/include/asm-arm/semaphore-helper.h deleted file mode 100644 index 1d7f1987ed..0000000000 --- a/include/asm-arm/semaphore-helper.h +++ /dev/null @@ -1,84 +0,0 @@ -#ifndef ASMARM_SEMAPHORE_HELPER_H -#define ASMARM_SEMAPHORE_HELPER_H - -/* - * These two _must_ execute atomically wrt each other. - */ -static inline void wake_one_more(struct semaphore * sem) -{ - unsigned long flags; - - spin_lock_irqsave(&semaphore_wake_lock, flags); - if (atomic_read(&sem->count) <= 0) - sem->waking++; - spin_unlock_irqrestore(&semaphore_wake_lock, flags); -} - -static inline int waking_non_zero(struct semaphore *sem) -{ - unsigned long flags; - int ret = 0; - - spin_lock_irqsave(&semaphore_wake_lock, flags); - if (sem->waking > 0) { - sem->waking--; - ret = 1; - } - spin_unlock_irqrestore(&semaphore_wake_lock, flags); - return ret; -} - -/* - * waking non zero interruptible - * 1 got the lock - * 0 go to sleep - * -EINTR interrupted - * - * We must undo the sem->count down_interruptible() increment while we are - * protected by the spinlock in order to make this atomic_inc() with the - * atomic_read() in wake_one_more(), otherwise we can race. -arca - */ -static inline int waking_non_zero_interruptible(struct semaphore *sem, - struct task_struct *tsk) -{ - unsigned long flags; - int ret = 0; - - spin_lock_irqsave(&semaphore_wake_lock, flags); - if (sem->waking > 0) { - sem->waking--; - ret = 1; - } else if (signal_pending(tsk)) { - atomic_inc(&sem->count); - ret = -EINTR; - } - spin_unlock_irqrestore(&semaphore_wake_lock, flags); - return ret; -} - -/* - * waking_non_zero_try_lock: - * 1 failed to lock - * 0 got the lock - * - * We must undo the sem->count down_interruptible() increment while we are - * protected by the spinlock in order to make this atomic_inc() with the - * atomic_read() in wake_one_more(), otherwise we can race. -arca - */ -static inline int waking_non_zero_trylock(struct semaphore *sem) -{ - unsigned long flags; - int ret = 1; - - spin_lock_irqsave(&semaphore_wake_lock, flags); - if (sem->waking <= 0) - atomic_inc(&sem->count); - else { - sem->waking--; - ret = 0; - } - spin_unlock_irqrestore(&semaphore_wake_lock, flags); - return ret; -} - -#endif diff --git a/include/asm-arm/semaphore.h b/include/asm-arm/semaphore.h index 1c8b441f89..d9b2034ed1 100644 --- a/include/asm-arm/semaphore.h +++ b/include/asm-arm/semaphore.h @@ -1,98 +1 @@ -/* - * linux/include/asm-arm/semaphore.h - */ -#ifndef __ASM_ARM_SEMAPHORE_H -#define __ASM_ARM_SEMAPHORE_H - -#include -#include -#include -#include - -#include -#include - -struct semaphore { - atomic_t count; - int sleepers; - wait_queue_head_t wait; -}; - -#define __SEMAPHORE_INIT(name, cnt) \ -{ \ - .count = ATOMIC_INIT(cnt), \ - .wait = __WAIT_QUEUE_HEAD_INITIALIZER((name).wait), \ -} - -#define __DECLARE_SEMAPHORE_GENERIC(name,count) \ - struct semaphore name = __SEMAPHORE_INIT(name,count) - -#define DECLARE_MUTEX(name) __DECLARE_SEMAPHORE_GENERIC(name,1) - -static inline void sema_init(struct semaphore *sem, int val) -{ - atomic_set(&sem->count, val); - sem->sleepers = 0; - init_waitqueue_head(&sem->wait); -} - -static inline void init_MUTEX(struct semaphore *sem) -{ - sema_init(sem, 1); -} - -static inline void init_MUTEX_LOCKED(struct semaphore *sem) -{ - sema_init(sem, 0); -} - -/* - * special register calling convention - */ -asmlinkage void __down_failed(void); -asmlinkage int __down_interruptible_failed(void); -asmlinkage int __down_trylock_failed(void); -asmlinkage void __up_wakeup(void); - -extern void __down(struct semaphore * sem); -extern int __down_interruptible(struct semaphore * sem); -extern int __down_trylock(struct semaphore * sem); -extern void __up(struct semaphore * sem); - -/* - * This is ugly, but we want the default case to fall through. - * "__down" is the actual routine that waits... - */ -static inline void down(struct semaphore * sem) -{ - might_sleep(); - __down_op(sem, __down_failed); -} - -/* - * This is ugly, but we want the default case to fall through. - * "__down_interruptible" is the actual routine that waits... - */ -static inline int down_interruptible (struct semaphore * sem) -{ - might_sleep(); - return __down_op_ret(sem, __down_interruptible_failed); -} - -static inline int down_trylock(struct semaphore *sem) -{ - return __down_op_ret(sem, __down_trylock_failed); -} - -/* - * Note! This is subtle. We jump to wake people up only if - * the semaphore was negative (== somebody was waiting on it). - * The default case (no contention) will result in NO - * jumps for both down() and up(). - */ -static inline void up(struct semaphore * sem) -{ - __up_op(sem, __up_wakeup); -} - -#endif +#include diff --git a/include/asm-avr32/semaphore.h b/include/asm-avr32/semaphore.h index feaf1d4533..d9b2034ed1 100644 --- a/include/asm-avr32/semaphore.h +++ b/include/asm-avr32/semaphore.h @@ -1,108 +1 @@ -/* - * SMP- and interrupt-safe semaphores. - * - * Copyright (C) 2006 Atmel Corporation - * - * Based on include/asm-i386/semaphore.h - * Copyright (C) 1996 Linus Torvalds - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License version 2 as - * published by the Free Software Foundation. - */ -#ifndef __ASM_AVR32_SEMAPHORE_H -#define __ASM_AVR32_SEMAPHORE_H - -#include - -#include -#include -#include -#include - -struct semaphore { - atomic_t count; - int sleepers; - wait_queue_head_t wait; -}; - -#define __SEMAPHORE_INITIALIZER(name, n) \ -{ \ - .count = ATOMIC_INIT(n), \ - .wait = __WAIT_QUEUE_HEAD_INITIALIZER((name).wait) \ -} - -#define __DECLARE_SEMAPHORE_GENERIC(name,count) \ - struct semaphore name = __SEMAPHORE_INITIALIZER(name,count) - -#define DECLARE_MUTEX(name) __DECLARE_SEMAPHORE_GENERIC(name,1) - -static inline void sema_init (struct semaphore *sem, int val) -{ - atomic_set(&sem->count, val); - sem->sleepers = 0; - init_waitqueue_head(&sem->wait); -} - -static inline void init_MUTEX (struct semaphore *sem) -{ - sema_init(sem, 1); -} - -static inline void init_MUTEX_LOCKED (struct semaphore *sem) -{ - sema_init(sem, 0); -} - -void __down(struct semaphore * sem); -int __down_interruptible(struct semaphore * sem); -void __up(struct semaphore * sem); - -/* - * This is ugly, but we want the default case to fall through. - * "__down_failed" is a special asm handler that calls the C - * routine that actually waits. See arch/i386/kernel/semaphore.c - */ -static inline void down(struct semaphore * sem) -{ - might_sleep(); - if (unlikely(atomic_dec_return (&sem->count) < 0)) - __down (sem); -} - -/* - * Interruptible try to acquire a semaphore. If we obtained - * it, return zero. If we were interrupted, returns -EINTR - */ -static inline int down_interruptible(struct semaphore * sem) -{ - int ret = 0; - - might_sleep(); - if (unlikely(atomic_dec_return (&sem->count) < 0)) - ret = __down_interruptible (sem); - return ret; -} - -/* - * Non-blockingly attempt to down() a semaphore. - * Returns zero if we acquired it - */ -static inline int down_trylock(struct semaphore * sem) -{ - return atomic_dec_if_positive(&sem->count) < 0; -} - -/* - * Note! This is subtle. We jump to wake people up only if - * the semaphore was negative (== somebody was waiting on it). - * The default case (no contention) will result in NO - * jumps for both down() and up(). - */ -static inline void up(struct semaphore * sem) -{ - if (unlikely(atomic_inc_return (&sem->count) <= 0)) - __up (sem); -} - -#endif /*__ASM_AVR32_SEMAPHORE_H */ +#include diff --git a/include/asm-blackfin/semaphore-helper.h b/include/asm-blackfin/semaphore-helper.h deleted file mode 100644 index 9082b0dc3e..0000000000 --- a/include/asm-blackfin/semaphore-helper.h +++ /dev/null @@ -1,82 +0,0 @@ -/* Based on M68K version, Lineo Inc. May 2001 */ - -#ifndef _BFIN_SEMAPHORE_HELPER_H -#define _BFIN_SEMAPHORE_HELPER_H - -/* - * SMP- and interrupt-safe semaphores helper functions. - * - * (C) Copyright 1996 Linus Torvalds - * - */ - -#include - -/* - * These two _must_ execute atomically wrt each other. - */ -static inline void wake_one_more(struct semaphore *sem) -{ - atomic_inc(&sem->waking); -} - -static inline int waking_non_zero(struct semaphore *sem) -{ - int ret; - unsigned long flags = 0; - - spin_lock_irqsave(&semaphore_wake_lock, flags); - ret = 0; - if (atomic_read(&sem->waking) > 0) { - atomic_dec(&sem->waking); - ret = 1; - } - spin_unlock_irqrestore(&semaphore_wake_lock, flags); - return ret; -} - -/* - * waking_non_zero_interruptible: - * 1 got the lock - * 0 go to sleep - * -EINTR interrupted - */ -static inline int waking_non_zero_interruptible(struct semaphore *sem, - struct task_struct *tsk) -{ - int ret = 0; - unsigned long flags = 0; - - spin_lock_irqsave(&semaphore_wake_lock, flags); - if (atomic_read(&sem->waking) > 0) { - atomic_dec(&sem->waking); - ret = 1; - } else if (signal_pending(tsk)) { - atomic_inc(&sem->count); - ret = -EINTR; - } - spin_unlock_irqrestore(&semaphore_wake_lock, flags); - return ret; -} - -/* - * waking_non_zero_trylock: - * 1 failed to lock - * 0 got the lock - */ -static inline int waking_non_zero_trylock(struct semaphore *sem) -{ - int ret = 1; - unsigned long flags = 0; - - spin_lock_irqsave(&semaphore_wake_lock, flags); - if (atomic_read(&sem->waking) > 0) { - atomic_dec(&sem->waking); - ret = 0; - } else - atomic_inc(&sem->count); - spin_unlock_irqrestore(&semaphore_wake_lock, flags); - return ret; -} - -#endif /* _BFIN_SEMAPHORE_HELPER_H */ diff --git a/include/asm-blackfin/semaphore.h b/include/asm-blackfin/semaphore.h index 533f90fb2e..d9b2034ed1 100644 --- a/include/asm-blackfin/semaphore.h +++ b/include/asm-blackfin/semaphore.h @@ -1,105 +1 @@ -#ifndef _BFIN_SEMAPHORE_H -#define _BFIN_SEMAPHORE_H - -#ifndef __ASSEMBLY__ - -#include -#include -#include -#include -#include - -/* - * Interrupt-safe semaphores.. - * - * (C) Copyright 1996 Linus Torvalds - * - * BFIN version by akbar hussain Lineo Inc April 2001 - * - */ - -struct semaphore { - atomic_t count; - int sleepers; - wait_queue_head_t wait; -}; - -#define __SEMAPHORE_INITIALIZER(name, n) \ -{ \ - .count = ATOMIC_INIT(n), \ - .sleepers = 0, \ - .wait = __WAIT_QUEUE_HEAD_INITIALIZER((name).wait) \ -} - -#define __DECLARE_SEMAPHORE_GENERIC(name,count) \ - struct semaphore name = __SEMAPHORE_INITIALIZER(name,count) - -#define DECLARE_MUTEX(name) __DECLARE_SEMAPHORE_GENERIC(name,1) - -static inline void sema_init(struct semaphore *sem, int val) -{ - *sem = (struct semaphore)__SEMAPHORE_INITIALIZER(*sem, val); -} - -static inline void init_MUTEX(struct semaphore *sem) -{ - sema_init(sem, 1); -} - -static inline void init_MUTEX_LOCKED(struct semaphore *sem) -{ - sema_init(sem, 0); -} - -asmlinkage void __down(struct semaphore *sem); -asmlinkage int __down_interruptible(struct semaphore *sem); -asmlinkage int __down_trylock(struct semaphore *sem); -asmlinkage void __up(struct semaphore *sem); - -extern spinlock_t semaphore_wake_lock; - -/* - * This is ugly, but we want the default case to fall through. - * "down_failed" is a special asm handler that calls the C - * routine that actually waits. - */ -static inline void down(struct semaphore *sem) -{ - might_sleep(); - if (atomic_dec_return(&sem->count) < 0) - __down(sem); -} - -static inline int down_interruptible(struct semaphore *sem) -{ - int ret = 0; - - might_sleep(); - if (atomic_dec_return(&sem->count) < 0) - ret = __down_interruptible(sem); - return (ret); -} - -static inline int down_trylock(struct semaphore *sem) -{ - int ret = 0; - - if (atomic_dec_return(&sem->count) < 0) - ret = __down_trylock(sem); - return ret; -} - -/* - * Note! This is subtle. We jump to wake people up only if - * the semaphore was negative (== somebody was waiting on it). - * The default case (no contention) will result in NO - * jumps for both down() and up(). - */ -static inline void up(struct semaphore *sem) -{ - if (atomic_inc_return(&sem->count) <= 0) - __up(sem); -} - -#endif /* __ASSEMBLY__ */ -#endif /* _BFIN_SEMAPHORE_H */ +#include diff --git a/include/asm-cris/semaphore-helper.h b/include/asm-cris/semaphore-helper.h deleted file mode 100644 index 27bfeca1b9..0000000000 --- a/include/asm-cris/semaphore-helper.h +++ /dev/null @@ -1,78 +0,0 @@ -/* $Id: semaphore-helper.h,v 1.3 2001/03/26 15:00:33 orjanf Exp $ - * - * SMP- and interrupt-safe semaphores helper functions. Generic versions, no - * optimizations whatsoever... - * - */ - -#ifndef _ASM_SEMAPHORE_HELPER_H -#define _ASM_SEMAPHORE_HELPER_H - -#include -#include - -#define read(a) ((a)->counter) -#define inc(a) (((a)->counter)++) -#define dec(a) (((a)->counter)--) - -#define count_inc(a) ((*(a))++) - -/* - * These two _must_ execute atomically wrt each other. - */ -static inline void wake_one_more(struct semaphore * sem) -{ - atomic_inc(&sem->waking); -} - -static inline int waking_non_zero(struct semaphore *sem) -{ - unsigned long flags; - int ret = 0; - - local_irq_save(flags); - if (read(&sem->waking) > 0) { - dec(&sem->waking); - ret = 1; - } - local_irq_restore(flags); - return ret; -} - -static inline int waking_non_zero_interruptible(struct semaphore *sem, - struct task_struct *tsk) -{ - int ret = 0; - unsigned long flags; - - local_irq_save(flags); - if (read(&sem->waking) > 0) { - dec(&sem->waking); - ret = 1; - } else if (signal_pending(tsk)) { - inc(&sem->count); - ret = -EINTR; - } - local_irq_restore(flags); - return ret; -} - -static inline int waking_non_zero_trylock(struct semaphore *sem) -{ - int ret = 1; - unsigned long flags; - - local_irq_save(flags); - if (read(&sem->waking) <= 0) - inc(&sem->count); - else { - dec(&sem->waking); - ret = 0; - } - local_irq_restore(flags); - return ret; -} - -#endif /* _ASM_SEMAPHORE_HELPER_H */ - - diff --git a/include/asm-cris/semaphore.h b/include/asm-cris/semaphore.h index 31a4ac4481..d9b2034ed1 100644 --- a/include/asm-cris/semaphore.h +++ b/include/asm-cris/semaphore.h @@ -1,133 +1 @@ -/* $Id: semaphore.h,v 1.3 2001/05/08 13:54:09 bjornw Exp $ */ - -/* On the i386 these are coded in asm, perhaps we should as well. Later.. */ - -#ifndef _CRIS_SEMAPHORE_H -#define _CRIS_SEMAPHORE_H - -#define RW_LOCK_BIAS 0x01000000 - -#include -#include -#include - -#include -#include - -/* - * CRIS semaphores, implemented in C-only so far. - */ - -struct semaphore { - atomic_t count; - atomic_t waking; - wait_queue_head_t wait; -}; - -#define __SEMAPHORE_INITIALIZER(name, n) \ -{ \ - .count = ATOMIC_INIT(n), \ - .waking = ATOMIC_INIT(0), \ - .wait = __WAIT_QUEUE_HEAD_INITIALIZER((name).wait) \ -} - -#define __DECLARE_SEMAPHORE_GENERIC(name,count) \ - struct semaphore name = __SEMAPHORE_INITIALIZER(name,count) - -#define DECLARE_MUTEX(name) __DECLARE_SEMAPHORE_GENERIC(name,1) - -static inline void sema_init(struct semaphore *sem, int val) -{ - *sem = (struct semaphore)__SEMAPHORE_INITIALIZER((*sem),val); -} - -static inline void init_MUTEX (struct semaphore *sem) -{ - sema_init(sem, 1); -} - -static inline void init_MUTEX_LOCKED (struct semaphore *sem) -{ - sema_init(sem, 0); -} - -extern void __down(struct semaphore * sem); -extern int __down_interruptible(struct semaphore * sem); -extern int __down_trylock(struct semaphore * sem); -extern void __up(struct semaphore * sem); - -/* notice - we probably can do cli/sti here instead of saving */ - -static inline void down(struct semaphore * sem) -{ - unsigned long flags; - int failed; - - might_sleep(); - - /* atomically decrement the semaphores count, and if its negative, we wait */ - cris_atomic_save(sem, flags); - failed = --(sem->count.counter) < 0; - cris_atomic_restore(sem, flags); - if(failed) { - __down(sem); - } -} - -/* - * This version waits in interruptible state so that the waiting - * process can be killed. The down_interruptible routine - * returns negative for signalled and zero for semaphore acquired. - */ - -static inline int down_interruptible(struct semaphore * sem) -{ - unsigned long flags; - int failed; - - might_sleep(); - - /* atomically decrement the semaphores count, and if its negative, we wait */ - cris_atomic_save(sem, flags); - failed = --(sem->count.counter) < 0; - cris_atomic_restore(sem, flags); - if(failed) - failed = __down_interruptible(sem); - return(failed); -} - -static inline int down_trylock(struct semaphore * sem) -{ - unsigned long flags; - int failed; - - cris_atomic_save(sem, flags); - failed = --(sem->count.counter) < 0; - cris_atomic_restore(sem, flags); - if(failed) - failed = __down_trylock(sem); - return(failed); - -} - -/* - * Note! This is subtle. We jump to wake people up only if - * the semaphore was negative (== somebody was waiting on it). - * The default case (no contention) will result in NO - * jumps for both down() and up(). - */ -static inline void up(struct semaphore * sem) -{ - unsigned long flags; - int wakeup; - - /* atomically increment the semaphores count, and if it was negative, we wake people */ - cris_atomic_save(sem, flags); - wakeup = ++(sem->count.counter) <= 0; - cris_atomic_restore(sem, flags); - if(wakeup) { - __up(sem); - } -} - -#endif +#include diff --git a/include/asm-frv/semaphore.h b/include/asm-frv/semaphore.h index d7aaa1911a..d9b2034ed1 100644 --- a/include/asm-frv/semaphore.h +++ b/include/asm-frv/semaphore.h @@ -1,155 +1 @@ -/* semaphore.h: semaphores for the FR-V - * - * Copyright (C) 2003 Red Hat, Inc. All Rights Reserved. - * Written by David Howells (dhowells@redhat.com) - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public License - * as published by the Free Software Foundation; either version - * 2 of the License, or (at your option) any later version. - */ -#ifndef _ASM_SEMAPHORE_H -#define _ASM_SEMAPHORE_H - -#define RW_LOCK_BIAS 0x01000000 - -#ifndef __ASSEMBLY__ - -#include -#include -#include -#include - -/* - * the semaphore definition - * - if counter is >0 then there are tokens available on the semaphore for down to collect - * - if counter is <=0 then there are no spare tokens, and anyone that wants one must wait - * - if wait_list is not empty, then there are processes waiting for the semaphore - */ -struct semaphore { - unsigned counter; - spinlock_t wait_lock; - struct list_head wait_list; -#ifdef CONFIG_DEBUG_SEMAPHORE - unsigned __magic; -#endif -}; - -#ifdef CONFIG_DEBUG_SEMAPHORE -# define __SEM_DEBUG_INIT(name) , (long)&(name).__magic -#else -# define __SEM_DEBUG_INIT(name) -#endif - - -#define __SEMAPHORE_INITIALIZER(name,count) \ -{ count, SPIN_LOCK_UNLOCKED, LIST_HEAD_INIT((name).wait_list) __SEM_DEBUG_INIT(name) } - -#define __DECLARE_SEMAPHORE_GENERIC(name,count) \ - struct semaphore name = __SEMAPHORE_INITIALIZER(name,count) - -#define DECLARE_MUTEX(name) __DECLARE_SEMAPHORE_GENERIC(name,1) - -static inline void sema_init (struct semaphore *sem, int val) -{ - *sem = (struct semaphore) __SEMAPHORE_INITIALIZER(*sem, val); -} - -static inline void init_MUTEX (struct semaphore *sem) -{ - sema_init(sem, 1); -} - -static inline void init_MUTEX_LOCKED (struct semaphore *sem) -{ - sema_init(sem, 0); -} - -extern void __down(struct semaphore *sem, unsigned long flags); -extern int __down_interruptible(struct semaphore *sem, unsigned long flags); -extern void __up(struct semaphore *sem); - -static inline void down(struct semaphore *sem) -{ - unsigned long flags; - -#ifdef CONFIG_DEBUG_SEMAPHORE - CHECK_MAGIC(sem->__magic); -#endif - - spin_lock_irqsave(&sem->wait_lock, flags); - if (likely(sem->counter > 0)) { - sem->counter--; - spin_unlock_irqrestore(&sem->wait_lock, flags); - } - else { - __down(sem, flags); - } -} - -static inline int down_interruptible(struct semaphore *sem) -{ - unsigned long flags; - int ret = 0; - -#ifdef CONFIG_DEBUG_SEMAPHORE - CHECK_MAGIC(sem->__magic); -#endif - - spin_lock_irqsave(&sem->wait_lock, flags); - if (likely(sem->counter > 0)) { - sem->counter--; - spin_unlock_irqrestore(&sem->wait_lock, flags); - } - else { - ret = __down_interruptible(sem, flags); - } - return ret; -} - -/* - * non-blockingly attempt to down() a semaphore. - * - returns zero if we acquired it - */ -static inline int down_trylock(struct semaphore *sem) -{ - unsigned long flags; - int success = 0; - -#ifdef CONFIG_DEBUG_SEMAPHORE - CHECK_MAGIC(sem->__magic); -#endif - - spin_lock_irqsave(&sem->wait_lock, flags); - if (sem->counter > 0) { - sem->counter--; - success = 1; - } - spin_unlock_irqrestore(&sem->wait_lock, flags); - return !success; -} - -static inline void up(struct semaphore *sem) -{ - unsigned long flags; - -#ifdef CONFIG_DEBUG_SEMAPHORE - CHECK_MAGIC(sem->__magic); -#endif - - spin_lock_irqsave(&sem->wait_lock, flags); - if (!list_empty(&sem->wait_list)) - __up(sem); - else - sem->counter++; - spin_unlock_irqrestore(&sem->wait_lock, flags); -} - -static inline int sem_getcount(struct semaphore *sem) -{ - return sem->counter; -} - -#endif /* __ASSEMBLY__ */ - -#endif +#include diff --git a/include/asm-h8300/semaphore-helper.h b/include/asm-h8300/semaphore-helper.h deleted file mode 100644 index 4fea36be5f..0000000000 --- a/include/asm-h8300/semaphore-helper.h +++ /dev/null @@ -1,85 +0,0 @@ -#ifndef _H8300_SEMAPHORE_HELPER_H -#define _H8300_SEMAPHORE_HELPER_H - -/* - * SMP- and interrupt-safe semaphores helper functions. - * - * (C) Copyright 1996 Linus Torvalds - * - * based on - * m68k version by Andreas Schwab - */ - -#include - -/* - * These two _must_ execute atomically wrt each other. - */ -static inline void wake_one_more(struct semaphore * sem) -{ - atomic_inc((atomic_t *)&sem->sleepers); -} - -static inline int waking_non_zero(struct semaphore *sem) -{ - int ret; - unsigned long flags; - - spin_lock_irqsave(&semaphore_wake_lock, flags); - ret = 0; - if (sem->sleepers > 0) { - sem->sleepers--; - ret = 1; - } - spin_unlock_irqrestore(&semaphore_wake_lock, flags); - return ret; -} - -/* - * waking_non_zero_interruptible: - * 1 got the lock - * 0 go to sleep - * -EINTR interrupted - */ -static inline int waking_non_zero_interruptible(struct semaphore *sem, - struct task_struct *tsk) -{ - int ret; - unsigned long flags; - - spin_lock_irqsave(&semaphore_wake_lock, flags); - ret = 0; - if (sem->sleepers > 0) { - sem->sleepers--; - ret = 1; - } else if (signal_pending(tsk)) { - atomic_inc(&sem->count); - ret = -EINTR; - } - spin_unlock_irqrestore(&semaphore_wake_lock, flags); - return ret; -} - -/* - * waking_non_zero_trylock: - * 1 failed to lock - * 0 got the lock - */ -static inline int waking_non_zero_trylock(struct semaphore *sem) -{ - int ret; - unsigned long flags; - - spin_lock_irqsave(&semaphore_wake_lock, flags); - ret = 1; - if (sem->sleepers <= 0) - atomic_inc(&sem->count); - else { - sem->sleepers--; - ret = 0; - } - spin_unlock_irqrestore(&semaphore_wake_lock, flags); - return ret; -} - -#endif diff --git a/include/asm-h8300/semaphore.h b/include/asm-h8300/semaphore.h index f3ffff83ff..d9b2034ed1 100644 --- a/include/asm-h8300/semaphore.h +++ b/include/asm-h8300/semaphore.h @@ -1,190 +1 @@ -#ifndef _H8300_SEMAPHORE_H -#define _H8300_SEMAPHORE_H - -#define RW_LOCK_BIAS 0x01000000 - -#ifndef __ASSEMBLY__ - -#include -#include -#include -#include - -#include -#include - -/* - * Interrupt-safe semaphores.. - * - * (C) Copyright 1996 Linus Torvalds - * - * H8/300 version by Yoshinori Sato - */ - - -struct semaphore { - atomic_t count; - int sleepers; - wait_queue_head_t wait; -}; - -#define __SEMAPHORE_INITIALIZER(name, n) \ -{ \ - .count = ATOMIC_INIT(n), \ - .sleepers = 0, \ - .wait = __WAIT_QUEUE_HEAD_INITIALIZER((name).wait) \ -} - -#define __DECLARE_SEMAPHORE_GENERIC(name,count) \ - struct semaphore name = __SEMAPHORE_INITIALIZER(name,count) - -#define DECLARE_MUTEX(name) __DECLARE_SEMAPHORE_GENERIC(name,1) - -static inline void sema_init (struct semaphore *sem, int val) -{ - *sem = (struct semaphore)__SEMAPHORE_INITIALIZER(*sem, val); -} - -static inline void init_MUTEX (struct semaphore *sem) -{ - sema_init(sem, 1); -} - -static inline void init_MUTEX_LOCKED (struct semaphore *sem) -{ - sema_init(sem, 0); -} - -asmlinkage void __down_failed(void /* special register calling convention */); -asmlinkage int __down_failed_interruptible(void /* params in registers */); -asmlinkage int __down_failed_trylock(void /* params in registers */); -asmlinkage void __up_wakeup(void /* special register calling convention */); - -asmlinkage void __down(struct semaphore * sem); -asmlinkage int __down_interruptible(struct semaphore * sem); -asmlinkage int __down_trylock(struct semaphore * sem); -asmlinkage void __up(struct semaphore * sem); - -extern spinlock_t semaphore_wake_lock; - -/* - * This is ugly, but we want the default case to fall through. - * "down_failed" is a special asm handler that calls the C - * routine that actually waits. See arch/m68k/lib/semaphore.S - */ -static inline void down(struct semaphore * sem) -{ - register atomic_t *count asm("er0"); - - might_sleep(); - - count = &(sem->count); - __asm__ __volatile__( - "stc ccr,r3l\n\t" - "orc #0x80,ccr\n\t" - "mov.l %2, er1\n\t" - "dec.l #1,er1\n\t" - "mov.l er1,%0\n\t" - "bpl 1f\n\t" - "ldc r3l,ccr\n\t" - "mov.l %1,er0\n\t" - "jsr @___down\n\t" - "bra 2f\n" - "1:\n\t" - "ldc r3l,ccr\n" - "2:" - : "=m"(*count) - : "g"(sem),"m"(*count) - : "cc", "er1", "er2", "er3"); -} - -static inline int down_interruptible(struct semaphore * sem) -{ - register atomic_t *count asm("er0"); - - might_sleep(); - - count = &(sem->count); - __asm__ __volatile__( - "stc ccr,r1l\n\t" - "orc #0x80,ccr\n\t" - "mov.l %3, er2\n\t" - "dec.l #1,er2\n\t" - "mov.l er2,%1\n\t" - "bpl 1f\n\t" - "ldc r1l,ccr\n\t" - "mov.l %2,er0\n\t" - "jsr @___down_interruptible\n\t" - "bra 2f\n" - "1:\n\t" - "ldc r1l,ccr\n\t" - "sub.l %0,%0\n\t" - "2:\n\t" - : "=r" (count),"=m" (*count) - : "g"(sem),"m"(*count) - : "cc", "er1", "er2", "er3"); - return (int)count; -} - -static inline int down_trylock(struct semaphore * sem) -{ - register atomic_t *count asm("er0"); - - count = &(sem->count); - __asm__ __volatile__( - "stc ccr,r3l\n\t" - "orc #0x80,ccr\n\t" - "mov.l %3,er2\n\t" - "dec.l #1,er2\n\t" - "mov.l er2,%0\n\t" - "bpl 1f\n\t" - "ldc r3l,ccr\n\t" - "jmp @3f\n\t" - LOCK_SECTION_START(".align 2\n\t") - "3:\n\t" - "mov.l %2,er0\n\t" - "jsr @___down_trylock\n\t" - "jmp @2f\n\t" - LOCK_SECTION_END - "1:\n\t" - "ldc r3l,ccr\n\t" - "sub.l %1,%1\n" - "2:" - : "=m" (*count),"=r"(count) - : "g"(sem),"m"(*count) - : "cc", "er1","er2", "er3"); - return (int)count; -} - -/* - * Note! This is subtle. We jump to wake people up only if - * the semaphore was negative (== somebody was waiting on it). - * The default case (no contention) will result in NO - * jumps for both down() and up(). - */ -static inline void up(struct semaphore * sem) -{ - register atomic_t *count asm("er0"); - - count = &(sem->count); - __asm__ __volatile__( - "stc ccr,r3l\n\t" - "orc #0x80,ccr\n\t" - "mov.l %2,er1\n\t" - "inc.l #1,er1\n\t" - "mov.l er1,%0\n\t" - "ldc r3l,ccr\n\t" - "sub.l er2,er2\n\t" - "cmp.l er2,er1\n\t" - "bgt 1f\n\t" - "mov.l %1,er0\n\t" - "jsr @___up\n" - "1:" - : "=m"(*count) - : "g"(sem),"m"(*count) - : "cc", "er1", "er2", "er3"); -} - -#endif /* __ASSEMBLY__ */ - -#endif +#include diff --git a/include/asm-ia64/semaphore.h b/include/asm-ia64/semaphore.h index d8393d1128..d9b2034ed1 100644 --- a/include/asm-ia64/semaphore.h +++ b/include/asm-ia64/semaphore.h @@ -1,99 +1 @@ -#ifndef _ASM_IA64_SEMAPHORE_H -#define _ASM_IA64_SEMAPHORE_H - -/* - * Copyright (C) 1998-2000 Hewlett-Packard Co - * Copyright (C) 1998-2000 David Mosberger-Tang - */ - -#include -#include - -#include - -struct semaphore { - atomic_t count; - int sleepers; - wait_queue_head_t wait; -}; - -#define __SEMAPHORE_INITIALIZER(name, n) \ -{ \ - .count = ATOMIC_INIT(n), \ - .sleepers = 0, \ - .wait = __WAIT_QUEUE_HEAD_INITIALIZER((name).wait) \ -} - -#define __DECLARE_SEMAPHORE_GENERIC(name,count) \ - struct semaphore name = __SEMAPHORE_INITIALIZER(name, count) - -#define DECLARE_MUTEX(name) __DECLARE_SEMAPHORE_GENERIC(name, 1) - -static inline void -sema_init (struct semaphore *sem, int val) -{ - *sem = (struct semaphore) __SEMAPHORE_INITIALIZER(*sem, val); -} - -static inline void -init_MUTEX (struct semaphore *sem) -{ - sema_init(sem, 1); -} - -static inline void -init_MUTEX_LOCKED (struct semaphore *sem) -{ - sema_init(sem, 0); -} - -extern void __down (struct semaphore * sem); -extern int __down_interruptible (struct semaphore * sem); -extern int __down_trylock (struct semaphore * sem); -extern void __up (struct semaphore * sem); - -/* - * Atomically decrement the semaphore's count. If it goes negative, - * block the calling thread in the TASK_UNINTERRUPTIBLE state. - */ -static inline void -down (struct semaphore *sem) -{ - might_sleep(); - if (ia64_fetchadd(-1, &sem->count.counter, acq) < 1) - __down(sem); -} - -/* - * Atomically decrement the semaphore's count. If it goes negative, - * block the calling thread in the TASK_INTERRUPTIBLE state. - */ -static inline int -down_interruptible (struct semaphore * sem) -{ - int ret = 0; - - might_sleep(); - if (ia64_fetchadd(-1, &sem->count.counter, acq) < 1) - ret = __down_interruptible(sem); - return ret; -} - -static inline int -down_trylock (struct semaphore *sem) -{ - int ret = 0; - - if (ia64_fetchadd(-1, &sem->count.counter, acq) < 1) - ret = __down_trylock(sem); - return ret; -} - -static inline void -up (struct semaphore * sem) -{ - if (ia64_fetchadd(1, &sem->count.counter, rel) <= -1) - __up(sem); -} - -#endif /* _ASM_IA64_SEMAPHORE_H */ +#include diff --git a/include/asm-m32r/semaphore.h b/include/asm-m32r/semaphore.h index b5bf95a6f2..d9b2034ed1 100644 --- a/include/asm-m32r/semaphore.h +++ b/include/asm-m32r/semaphore.h @@ -1,144 +1 @@ -#ifndef _ASM_M32R_SEMAPHORE_H -#define _ASM_M32R_SEMAPHORE_H - -#include - -#ifdef __KERNEL__ - -/* - * SMP- and interrupt-safe semaphores.. - * - * Copyright (C) 1996 Linus Torvalds - * Copyright (C) 2004, 2006 Hirokazu Takata - */ - -#include -#include -#include -#include -#include - -struct semaphore { - atomic_t count; - int sleepers; - wait_queue_head_t wait; -}; - -#define __SEMAPHORE_INITIALIZER(name, n) \ -{ \ - .count = ATOMIC_INIT(n), \ - .sleepers = 0, \ - .wait = __WAIT_QUEUE_HEAD_INITIALIZER((name).wait) \ -} - -#define __DECLARE_SEMAPHORE_GENERIC(name,count) \ - struct semaphore name = __SEMAPHORE_INITIALIZER(name,count) - -#define DECLARE_MUTEX(name) __DECLARE_SEMAPHORE_GENERIC(name,1) - -static inline void sema_init (struct semaphore *sem, int val) -{ -/* - * *sem = (struct semaphore)__SEMAPHORE_INITIALIZER((*sem),val); - * - * i'd rather use the more flexible initialization above, but sadly - * GCC 2.7.2.3 emits a bogus warning. EGCS doesnt. Oh well. - */ - atomic_set(&sem->count, val); - sem->sleepers = 0; - init_waitqueue_head(&sem->wait); -} - -static inline void init_MUTEX (struct semaphore *sem) -{ - sema_init(sem, 1); -} - -static inline void init_MUTEX_LOCKED (struct semaphore *sem) -{ - sema_init(sem, 0); -} - -asmlinkage void __down_failed(void /* special register calling convention */); -asmlinkage int __down_failed_interruptible(void /* params in registers */); -asmlinkage int __down_failed_trylock(void /* params in registers */); -asmlinkage void __up_wakeup(void /* special register calling convention */); - -asmlinkage void __down(struct semaphore * sem); -asmlinkage int __down_interruptible(struct semaphore * sem); -asmlinkage int __down_trylock(struct semaphore * sem); -asmlinkage void __up(struct semaphore * sem); - -/* - * Atomically decrement the semaphore's count. If it goes negative, - * block the calling thread in the TASK_UNINTERRUPTIBLE state. - */ -static inline void down(struct semaphore * sem) -{ - might_sleep(); - if (unlikely(atomic_dec_return(&sem->count) < 0)) - __down(sem); -} - -/* - * Interruptible try to acquire a semaphore. If we obtained - * it, return zero. If we were interrupted, returns -EINTR - */ -static inline int down_interruptible(struct semaphore * sem) -{ - int result = 0; - - might_sleep(); - if (unlikely(atomic_dec_return(&sem->count) < 0)) - result = __down_interruptible(sem); - - return result; -} - -/* - * Non-blockingly attempt to down() a semaphore. - * Returns zero if we acquired it - */ -static inline int down_trylock(struct semaphore * sem) -{ - unsigned long flags; - long count; - int result = 0; - - local_irq_save(flags); - __asm__ __volatile__ ( - "# down_trylock \n\t" - DCACHE_CLEAR("%0", "r4", "%1") - M32R_LOCK" %0, @%1; \n\t" - "addi %0, #-1; \n\t" - M32R_UNLOCK" %0, @%1; \n\t" - : "=&r" (count) - : "r" (&sem->count) - : "memory" -#ifdef CONFIG_CHIP_M32700_TS1 - , "r4" -#endif /* CONFIG_CHIP_M32700_TS1 */ - ); - local_irq_restore(flags); - - if (unlikely(count < 0)) - result = __down_trylock(sem); - - return result; -} - -/* - * Note! This is subtle. We jump to wake people up only if - * the semaphore was negative (== somebody was waiting on it). - * The default case (no contention) will result in NO - * jumps for both down() and up(). - */ -static inline void up(struct semaphore * sem) -{ - if (unlikely(atomic_inc_return(&sem->count) <= 0)) - __up(sem); -} - -#endif /* __KERNEL__ */ - -#endif /* _ASM_M32R_SEMAPHORE_H */ +#include diff --git a/include/asm-m68k/semaphore-helper.h b/include/asm-m68k/semaphore-helper.h deleted file mode 100644 index eef30ba0b4..0000000000 --- a/include/asm-m68k/semaphore-helper.h +++ /dev/null @@ -1,142 +0,0 @@ -#ifndef _M68K_SEMAPHORE_HELPER_H -#define _M68K_SEMAPHORE_HELPER_H - -/* - * SMP- and interrupt-safe semaphores helper functions. - * - * (C) Copyright 1996 Linus Torvalds - * - * m68k version by Andreas Schwab - */ - -#include - -/* - * These two _must_ execute atomically wrt each other. - */ -static inline void wake_one_more(struct semaphore * sem) -{ - atomic_inc(&sem->waking); -} - -#ifndef CONFIG_RMW_INSNS -extern spinlock_t semaphore_wake_lock; -#endif - -static inline int waking_non_zero(struct semaphore *sem) -{ - int ret; -#ifndef CONFIG_RMW_INSNS - unsigned long flags; - - spin_lock_irqsave(&semaphore_wake_lock, flags); - ret = 0; - if (atomic_read(&sem->waking) > 0) { - atomic_dec(&sem->waking); - ret = 1; - } - spin_unlock_irqrestore(&semaphore_wake_lock, flags); -#else - int tmp1, tmp2; - - __asm__ __volatile__ - ("1: movel %1,%2\n" - " jle 2f\n" - " subql #1,%2\n" - " casl %1,%2,%3\n" - " jne 1b\n" - " moveq #1,%0\n" - "2:" - : "=d" (ret), "=d" (tmp1), "=d" (tmp2) - : "m" (sem->waking), "0" (0), "1" (sem->waking)); -#endif - - return ret; -} - -/* - * waking_non_zero_interruptible: - * 1 got the lock - * 0 go to sleep - * -EINTR interrupted - */ -static inline int waking_non_zero_interruptible(struct semaphore *sem, - struct task_struct *tsk) -{ - int ret; -#ifndef CONFIG_RMW_INSNS - unsigned long flags; - - spin_lock_irqsave(&semaphore_wake_lock, flags); - ret = 0; - if (atomic_read(&sem->waking) > 0) { - atomic_dec(&sem->waking); - ret = 1; - } else if (signal_pending(tsk)) { - atomic_inc(&sem->count); - ret = -EINTR; - } - spin_unlock_irqrestore(&semaphore_wake_lock, flags); -#else - int tmp1, tmp2; - - __asm__ __volatile__ - ("1: movel %1,%2\n" - " jle 2f\n" - " subql #1,%2\n" - " casl %1,%2,%3\n" - " jne 1b\n" - " moveq #1,%0\n" - " jra %a4\n" - "2:" - : "=d" (ret), "=d" (tmp1), "=d" (tmp2) - : "m" (sem->waking), "i" (&&next), "0" (0), "1" (sem->waking)); - if (signal_pending(tsk)) { - atomic_inc(&sem->count); - ret = -EINTR; - } -next: -#endif - - return ret; -} - -/* - * waking_non_zero_trylock: - * 1 failed to lock - * 0 got the lock - */ -static inline int waking_non_zero_trylock(struct semaphore *sem) -{ - int ret; -#ifndef CONFIG_RMW_INSNS - unsigned long flags; - - spin_lock_irqsave(&semaphore_wake_lock, flags); - ret = 1; - if (atomic_read(&sem->waking) > 0) { - atomic_dec(&sem->waking); - ret = 0; - } else - atomic_inc(&sem->count); - spin_unlock_irqrestore(&semaphore_wake_lock, flags); -#else - int tmp1, tmp2; - - __asm__ __volatile__ - ("1: movel %1,%2\n" - " jle 2f\n" - " subql #1,%2\n" - " casl %1,%2,%3\n" - " jne 1b\n" - " moveq #0,%0\n" - "2:" - : "=d" (ret), "=d" (tmp1), "=d" (tmp2) - : "m" (sem->waking), "0" (1), "1" (sem->waking)); - if (ret) - atomic_inc(&sem->count); -#endif - return ret; -} - -#endif diff --git a/include/asm-m68k/semaphore.h b/include/asm-m68k/semaphore.h index 64d6b119bb..d9b2034ed1 100644 --- a/include/asm-m68k/semaphore.h +++ b/include/asm-m68k/semaphore.h @@ -1,163 +1 @@ -#ifndef _M68K_SEMAPHORE_H -#define _M68K_SEMAPHORE_H - -#define RW_LOCK_BIAS 0x01000000 - -#ifndef __ASSEMBLY__ - -#include -#include -#include -#include -#include - -#include -#include - -/* - * Interrupt-safe semaphores.. - * - * (C) Copyright 1996 Linus Torvalds - * - * m68k version by Andreas Schwab - */ - - -struct semaphore { - atomic_t count; - atomic_t waking; - wait_queue_head_t wait; -}; - -#define __SEMAPHORE_INITIALIZER(name, n) \ -{ \ - .count = ATOMIC_INIT(n), \ - .waking = ATOMIC_INIT(0), \ - .wait = __WAIT_QUEUE_HEAD_INITIALIZER((name).wait) \ -} - -#define __DECLARE_SEMAPHORE_GENERIC(name,count) \ - struct semaphore name = __SEMAPHORE_INITIALIZER(name,count) - -#define DECLARE_MUTEX(name) __DECLARE_SEMAPHORE_GENERIC(name,1) - -static inline void sema_init(struct semaphore *sem, int val) -{ - *sem = (struct semaphore)__SEMAPHORE_INITIALIZER(*sem, val); -} - -static inline void init_MUTEX (struct semaphore *sem) -{ - sema_init(sem, 1); -} - -static inline void init_MUTEX_LOCKED (struct semaphore *sem) -{ - sema_init(sem, 0); -} - -asmlinkage void __down_failed(void /* special register calling convention */); -asmlinkage int __down_failed_interruptible(void /* params in registers */); -asmlinkage int __down_failed_trylock(void /* params in registers */); -asmlinkage void __up_wakeup(void /* special register calling convention */); - -asmlinkage void __down(struct semaphore * sem); -asmlinkage int __down_interruptible(struct semaphore * sem); -asmlinkage int __down_trylock(struct semaphore * sem); -asmlinkage void __up(struct semaphore * sem); - -/* - * This is ugly, but we want the default case to fall through. - * "down_failed" is a special asm handler that calls the C - * routine that actually waits. See arch/m68k/lib/semaphore.S - */ -static inline void down(struct semaphore *sem) -{ - register struct semaphore *sem1 __asm__ ("%a1") = sem; - - might_sleep(); - __asm__ __volatile__( - "| atomic down operation\n\t" - "subql #1,%0@\n\t" - "jmi 2f\n\t" - "1:\n" - LOCK_SECTION_START(".even\n\t") - "2:\tpea 1b\n\t" - "jbra __down_failed\n" - LOCK_SECTION_END - : /* no outputs */ - : "a" (sem1) - : "memory"); -} - -static inline int down_interruptible(struct semaphore *sem) -{ - register struct semaphore *sem1 __asm__ ("%a1") = sem; - register int result __asm__ ("%d0"); - - might_sleep(); - __asm__ __volatile__( - "| atomic interruptible down operation\n\t" - "subql #1,%1@\n\t" - "jmi 2f\n\t" - "clrl %0\n" - "1:\n" - LOCK_SECTION_START(".even\n\t") - "2:\tpea 1b\n\t" - "jbra __down_failed_interruptible\n" - LOCK_SECTION_END - : "=d" (result) - : "a" (sem1) - : "memory"); - return result; -} - -static inline int down_trylock(struct semaphore *sem) -{ - register struct semaphore *sem1 __asm__ ("%a1") = sem; - register int result __asm__ ("%d0"); - - __asm__ __volatile__( - "| atomic down trylock operation\n\t" - "subql #1,%1@\n\t" - "jmi 2f\n\t" - "clrl %0\n" - "1:\n" - LOCK_SECTION_START(".even\n\t") - "2:\tpea 1b\n\t" - "jbra __down_failed_trylock\n" - LOCK_SECTION_END - : "=d" (result) - : "a" (sem1) - : "memory"); - return result; -} - -/* - * Note! This is subtle. We jump to wake people up only if - * the semaphore was negative (== somebody was waiting on it). - * The default case (no contention) will result in NO - * jumps for both down() and up(). - */ -static inline void up(struct semaphore *sem) -{ - register struct semaphore *sem1 __asm__ ("%a1") = sem; - - __asm__ __volatile__( - "| atomic up operation\n\t" - "addql #1,%0@\n\t" - "jle 2f\n" - "1:\n" - LOCK_SECTION_START(".even\n\t") - "2:\t" - "pea 1b\n\t" - "jbra __up_wakeup\n" - LOCK_SECTION_END - : /* no outputs */ - : "a" (sem1) - : "memory"); -} - -#endif /* __ASSEMBLY__ */ - -#endif +#include diff --git a/include/asm-m68knommu/semaphore-helper.h b/include/asm-m68knommu/semaphore-helper.h deleted file mode 100644 index 43da7bc483..0000000000 --- a/include/asm-m68knommu/semaphore-helper.h +++ /dev/null @@ -1,82 +0,0 @@ -#ifndef _M68K_SEMAPHORE_HELPER_H -#define _M68K_SEMAPHORE_HELPER_H - -/* - * SMP- and interrupt-safe semaphores helper functions. - * - * (C) Copyright 1996 Linus Torvalds - * - * m68k version by Andreas Schwab - */ - - -/* - * These two _must_ execute atomically wrt each other. - */ -static inline void wake_one_more(struct semaphore * sem) -{ - atomic_inc(&sem->waking); -} - -static inline int waking_non_zero(struct semaphore *sem) -{ - int ret; - unsigned long flags; - - spin_lock_irqsave(&semaphore_wake_lock, flags); - ret = 0; - if (atomic_read(&sem->waking) > 0) { - atomic_dec(&sem->waking); - ret = 1; - } - spin_unlock_irqrestore(&semaphore_wake_lock, flags); - return ret; -} - -/* - * waking_non_zero_interruptible: - * 1 got the lock - * 0 go to sleep - * -EINTR interrupted - */ -static inline int waking_non_zero_interruptible(struct semaphore *sem, - struct task_struct *tsk) -{ - int ret; - unsigned long flags; - - spin_lock_irqsave(&semaphore_wake_lock, flags); - ret = 0; - if (atomic_read(&sem->waking) > 0) { - atomic_dec(&sem->waking); - ret = 1; - } else if (signal_pending(tsk)) { - atomic_inc(&sem->count); - ret = -EINTR; - } - spin_unlock_irqrestore(&semaphore_wake_lock, flags); - return ret; -} - -/* - * waking_non_zero_trylock: - * 1 failed to lock - * 0 got the lock - */ -static inline int waking_non_zero_trylock(struct semaphore *sem) -{ - int ret; - unsigned long flags; - - spin_lock_irqsave(&semaphore_wake_lock, flags); - ret = 1; - if (atomic_read(&sem->waking) > 0) { - atomic_dec(&sem->waking); - ret = 0; - } else - atomic_inc(&sem->count); - spin_unlock_irqrestore(&semaphore_wake_lock, flags); - return ret; -} - -#endif diff --git a/include/asm-m68knommu/semaphore.h b/include/asm-m68knommu/semaphore.h index 5779eb6c06..d9b2034ed1 100644 --- a/include/asm-m68knommu/semaphore.h +++ b/include/asm-m68knommu/semaphore.h @@ -1,153 +1 @@ -#ifndef _M68K_SEMAPHORE_H -#define _M68K_SEMAPHORE_H - -#define RW_LOCK_BIAS 0x01000000 - -#ifndef __ASSEMBLY__ - -#include -#include -#include -#include - -#include -#include - -/* - * Interrupt-safe semaphores.. - * - * (C) Copyright 1996 Linus Torvalds - * - * m68k version by Andreas Schwab - */ - - -struct semaphore { - atomic_t count; - atomic_t waking; - wait_queue_head_t wait; -}; - -#define __SEMAPHORE_INITIALIZER(name, n) \ -{ \ - .count = ATOMIC_INIT(n), \ - .waking = ATOMIC_INIT(0), \ - .wait = __WAIT_QUEUE_HEAD_INITIALIZER((name).wait) \ -} - -#define __DECLARE_SEMAPHORE_GENERIC(name,count) \ - struct semaphore name = __SEMAPHORE_INITIALIZER(name,count) - -#define DECLARE_MUTEX(name) __DECLARE_SEMAPHORE_GENERIC(name,1) - -static inline void sema_init (struct semaphore *sem, int val) -{ - *sem = (struct semaphore)__SEMAPHORE_INITIALIZER(*sem, val); -} - -static inline void init_MUTEX (struct semaphore *sem) -{ - sema_init(sem, 1); -} - -static inline void init_MUTEX_LOCKED (struct semaphore *sem) -{ - sema_init(sem, 0); -} - -asmlinkage void __down_failed(void /* special register calling convention */); -asmlinkage int __down_failed_interruptible(void /* params in registers */); -asmlinkage int __down_failed_trylock(void /* params in registers */); -asmlinkage void __up_wakeup(void /* special register calling convention */); - -asmlinkage void __down(struct semaphore * sem); -asmlinkage int __down_interruptible(struct semaphore * sem); -asmlinkage int __down_trylock(struct semaphore * sem); -asmlinkage void __up(struct semaphore * sem); - -extern spinlock_t semaphore_wake_lock; - -/* - * This is ugly, but we want the default case to fall through. - * "down_failed" is a special asm handler that calls the C - * routine that actually waits. See arch/m68k/lib/semaphore.S - */ -static inline void down(struct semaphore * sem) -{ - might_sleep(); - __asm__ __volatile__( - "| atomic down operation\n\t" - "movel %0, %%a1\n\t" - "lea %%pc@(1f), %%a0\n\t" - "subql #1, %%a1@\n\t" - "jmi __down_failed\n" - "1:" - : /* no outputs */ - : "g" (sem) - : "cc", "%a0", "%a1", "memory"); -} - -static inline int down_interruptible(struct semaphore * sem) -{ - int ret; - - might_sleep(); - __asm__ __volatile__( - "| atomic down operation\n\t" - "movel %1, %%a1\n\t" - "lea %%pc@(1f), %%a0\n\t" - "subql #1, %%a1@\n\t" - "jmi __down_failed_interruptible\n\t" - "clrl %%d0\n" - "1: movel %%d0, %0\n" - : "=d" (ret) - : "g" (sem) - : "cc", "%d0", "%a0", "%a1", "memory"); - return(ret); -} - -static inline int down_trylock(struct semaphore * sem) -{ - register struct semaphore *sem1 __asm__ ("%a1") = sem; - register int result __asm__ ("%d0"); - - __asm__ __volatile__( - "| atomic down trylock operation\n\t" - "subql #1,%1@\n\t" - "jmi 2f\n\t" - "clrl %0\n" - "1:\n" - ".section .text.lock,\"ax\"\n" - ".even\n" - "2:\tpea 1b\n\t" - "jbra __down_failed_trylock\n" - ".previous" - : "=d" (result) - : "a" (sem1) - : "memory"); - return result; -} - -/* - * Note! This is subtle. We jump to wake people up only if - * the semaphore was negative (== somebody was waiting on it). - * The default case (no contention) will result in NO - * jumps for both down() and up(). - */ -static inline void up(struct semaphore * sem) -{ - __asm__ __volatile__( - "| atomic up operation\n\t" - "movel %0, %%a1\n\t" - "lea %%pc@(1f), %%a0\n\t" - "addql #1, %%a1@\n\t" - "jle __up_wakeup\n" - "1:" - : /* no outputs */ - : "g" (sem) - : "cc", "%a0", "%a1", "memory"); -} - -#endif /* __ASSEMBLY__ */ - -#endif +#include diff --git a/include/asm-mips/semaphore.h b/include/asm-mips/semaphore.h index fdf8042b78..d9b2034ed1 100644 --- a/include/asm-mips/semaphore.h +++ b/include/asm-mips/semaphore.h @@ -1,108 +1 @@ -/* - * This file is subject to the terms and conditions of the GNU General Public - * License. See the file "COPYING" in the main directory of this archive - * for more details. - * - * Copyright (C) 1996 Linus Torvalds - * Copyright (C) 1998, 99, 2000, 01, 04 Ralf Baechle - * Copyright (C) 1999, 2000, 01 Silicon Graphics, Inc. - * Copyright (C) 2000, 01 MIPS Technologies, Inc. - * - * In all honesty, little of the old MIPS code left - the PPC64 variant was - * just looking nice and portable so I ripped it. Credits to whoever wrote - * it. - */ -#ifndef __ASM_SEMAPHORE_H -#define __ASM_SEMAPHORE_H - -/* - * Remove spinlock-based RW semaphores; RW semaphore definitions are - * now in rwsem.h and we use the generic lib/rwsem.c implementation. - * Rework semaphores to use atomic_dec_if_positive. - * -- Paul Mackerras (paulus@samba.org) - */ - -#ifdef __KERNEL__ - -#include -#include -#include -#include - -struct semaphore { - /* - * Note that any negative value of count is equivalent to 0, - * but additionally indicates that some process(es) might be - * sleeping on `wait'. - */ - atomic_t count; - wait_queue_head_t wait; -}; - -#define __SEMAPHORE_INITIALIZER(name, n) \ -{ \ - .count = ATOMIC_INIT(n), \ - .wait = __WAIT_QUEUE_HEAD_INITIALIZER((name).wait) \ -} - -#define __DECLARE_SEMAPHORE_GENERIC(name, count) \ - struct semaphore name = __SEMAPHORE_INITIALIZER(name, count) - -#define DECLARE_MUTEX(name) __DECLARE_SEMAPHORE_GENERIC(name, 1) - -static inline void sema_init(struct semaphore *sem, int val) -{ - atomic_set(&sem->count, val); - init_waitqueue_head(&sem->wait); -} - -static inline void init_MUTEX(struct semaphore *sem) -{ - sema_init(sem, 1); -} - -static inline void init_MUTEX_LOCKED(struct semaphore *sem) -{ - sema_init(sem, 0); -} - -extern void __down(struct semaphore * sem); -extern int __down_interruptible(struct semaphore * sem); -extern void __up(struct semaphore * sem); - -static inline void down(struct semaphore * sem) -{ - might_sleep(); - - /* - * Try to get the semaphore, take the slow path if we fail. - */ - if (unlikely(atomic_dec_return(&sem->count) < 0)) - __down(sem); -} - -static inline int down_interruptible(struct semaphore * sem) -{ - int ret = 0; - - might_sleep(); - - if (unlikely(atomic_dec_return(&sem->count) < 0)) - ret = __down_interruptible(sem); - return ret; -} - -static inline int down_trylock(struct semaphore * sem) -{ - return atomic_dec_if_positive(&sem->count) < 0; -} - -static inline void up(struct semaphore * sem) -{ - if (unlikely(atomic_inc_return(&sem->count) <= 0)) - __up(sem); -} - -#endif /* __KERNEL__ */ - -#endif /* __ASM_SEMAPHORE_H */ +#include diff --git a/include/asm-mn10300/semaphore.h b/include/asm-mn10300/semaphore.h index 5a9e1ad0b2..d9b2034ed1 100644 --- a/include/asm-mn10300/semaphore.h +++ b/include/asm-mn10300/semaphore.h @@ -1,169 +1 @@ -/* MN10300 Semaphores - * - * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved. - * Written by David Howells (dhowells@redhat.com) - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public Licence - * as published by the Free Software Foundation; either version - * 2 of the Licence, or (at your option) any later version. - */ -#ifndef _ASM_SEMAPHORE_H -#define _ASM_SEMAPHORE_H - -#ifndef __ASSEMBLY__ - -#include -#include -#include -#include - -#define SEMAPHORE_DEBUG 0 - -/* - * the semaphore definition - * - if count is >0 then there are tokens available on the semaphore for down - * to collect - * - if count is <=0 then there are no spare tokens, and anyone that wants one - * must wait - * - if wait_list is not empty, then there are processes waiting for the - * semaphore - */ -struct semaphore { - atomic_t count; /* it's not really atomic, it's - * just that certain modules - * expect to be able to access - * it directly */ - spinlock_t wait_lock; - struct list_head wait_list; -#if SEMAPHORE_DEBUG - unsigned __magic; -#endif -}; - -#if SEMAPHORE_DEBUG -# define __SEM_DEBUG_INIT(name) , (long)&(name).__magic -#else -# define __SEM_DEBUG_INIT(name) -#endif - - -#define __SEMAPHORE_INITIALIZER(name, init_count) \ -{ \ - .count = ATOMIC_INIT(init_count), \ - .wait_lock = __SPIN_LOCK_UNLOCKED((name).wait_lock), \ - .wait_list = LIST_HEAD_INIT((name).wait_list) \ - __SEM_DEBUG_INIT(name) \ -} - -#define __DECLARE_SEMAPHORE_GENERIC(name,count) \ - struct semaphore name = __SEMAPHORE_INITIALIZER(name, count) - -#define DECLARE_MUTEX(name) __DECLARE_SEMAPHORE_GENERIC(name, 1) -#define DECLARE_MUTEX_LOCKED(name) __DECLARE_SEMAPHORE_GENERIC(name, 0) - -static inline void sema_init(struct semaphore *sem, int val) -{ - *sem = (struct semaphore) __SEMAPHORE_INITIALIZER(*sem, val); -} - -static inline void init_MUTEX(struct semaphore *sem) -{ - sema_init(sem, 1); -} - -static inline void init_MUTEX_LOCKED(struct semaphore *sem) -{ - sema_init(sem, 0); -} - -extern void __down(struct semaphore *sem, unsigned long flags); -extern int __down_interruptible(struct semaphore *sem, unsigned long flags); -extern void __up(struct semaphore *sem); - -static inline void down(struct semaphore *sem) -{ - unsigned long flags; - int count; - -#if SEMAPHORE_DEBUG - CHECK_MAGIC(sem->__magic); -#endif - - spin_lock_irqsave(&sem->wait_lock, flags); - count = atomic_read(&sem->count); - if (likely(count > 0)) { - atomic_set(&sem->count, count - 1); - spin_unlock_irqrestore(&sem->wait_lock, flags); - } else { - __down(sem, flags); - } -} - -static inline int down_interruptible(struct semaphore *sem) -{ - unsigned long flags; - int count, ret = 0; - -#if SEMAPHORE_DEBUG - CHECK_MAGIC(sem->__magic); -#endif - - spin_lock_irqsave(&sem->wait_lock, flags); - count = atomic_read(&sem->count); - if (likely(count > 0)) { - atomic_set(&sem->count, count - 1); - spin_unlock_irqrestore(&sem->wait_lock, flags); - } else { - ret = __down_interruptible(sem, flags); - } - return ret; -} - -/* - * non-blockingly attempt to down() a semaphore. - * - returns zero if we acquired it - */ -static inline int down_trylock(struct semaphore *sem) -{ - unsigned long flags; - int count, success = 0; - -#if SEMAPHORE_DEBUG - CHECK_MAGIC(sem->__magic); -#endif - - spin_lock_irqsave(&sem->wait_lock, flags); - count = atomic_read(&sem->count); - if (likely(count > 0)) { - atomic_set(&sem->count, count - 1); - success = 1; - } - spin_unlock_irqrestore(&sem->wait_lock, flags); - return !success; -} - -static inline void up(struct semaphore *sem) -{ - unsigned long flags; - -#if SEMAPHORE_DEBUG - CHECK_MAGIC(sem->__magic); -#endif - - spin_lock_irqsave(&sem->wait_lock, flags); - if (!list_empty(&sem->wait_list)) - __up(sem); - else - atomic_set(&sem->count, atomic_read(&sem->count) + 1); - spin_unlock_irqrestore(&sem->wait_lock, flags); -} - -static inline int sem_getcount(struct semaphore *sem) -{ - return atomic_read(&sem->count); -} - -#endif /* __ASSEMBLY__ */ - -#endif +#include diff --git a/include/asm-parisc/semaphore-helper.h b/include/asm-parisc/semaphore-helper.h deleted file mode 100644 index 387f7c1277..0000000000 --- a/include/asm-parisc/semaphore-helper.h +++ /dev/null @@ -1,89 +0,0 @@ -#ifndef _ASM_PARISC_SEMAPHORE_HELPER_H -#define _ASM_PARISC_SEMAPHORE_HELPER_H - -/* - * SMP- and interrupt-safe semaphores helper functions. - * - * (C) Copyright 1996 Linus Torvalds - * (C) Copyright 1999 Andrea Arcangeli - */ - -/* - * These two _must_ execute atomically wrt each other. - * - * This is trivially done with load_locked/store_cond, - * which we have. Let the rest of the losers suck eggs. - */ -static __inline__ void wake_one_more(struct semaphore * sem) -{ - atomic_inc((atomic_t *)&sem->waking); -} - -static __inline__ int waking_non_zero(struct semaphore *sem) -{ - unsigned long flags; - int ret = 0; - - spin_lock_irqsave(&semaphore_wake_lock, flags); - if (sem->waking > 0) { - sem->waking--; - ret = 1; - } - spin_unlock_irqrestore(&semaphore_wake_lock, flags); - return ret; -} - -/* - * waking_non_zero_interruptible: - * 1 got the lock - * 0 go to sleep - * -EINTR interrupted - * - * We must undo the sem->count down_interruptible() increment while we are - * protected by the spinlock in order to make atomic this atomic_inc() with the - * atomic_read() in wake_one_more(), otherwise we can race. -arca - */ -static __inline__ int waking_non_zero_interruptible(struct semaphore *sem, - struct task_struct *tsk) -{ - unsigned long flags; - int ret = 0; - - spin_lock_irqsave(&semaphore_wake_lock, flags); - if (sem->waking > 0) { - sem->waking--; - ret = 1; - } else if (signal_pending(tsk)) { - atomic_inc(&sem->count); - ret = -EINTR; - } - spin_unlock_irqrestore(&semaphore_wake_lock, flags); - return ret; -} - -/* - * waking_non_zero_trylock: - * 1 failed to lock - * 0 got the lock - * - * We must undo the sem->count down_trylock() increment while we are - * protected by the spinlock in order to make atomic this atomic_inc() with the - * atomic_read() in wake_one_more(), otherwise we can race. -arca - */ -static __inline__ int waking_non_zero_trylock(struct semaphore *sem) -{ - unsigned long flags; - int ret = 1; - - spin_lock_irqsave(&semaphore_wake_lock, flags); - if (sem->waking <= 0) - atomic_inc(&sem->count); - else { - sem->waking--; - ret = 0; - } - spin_unlock_irqrestore(&semaphore_wake_lock, flags); - return ret; -} - -#endif /* _ASM_PARISC_SEMAPHORE_HELPER_H */ diff --git a/include/asm-parisc/semaphore.h b/include/asm-parisc/semaphore.h index a16271cdc7..d9b2034ed1 100644 --- a/include/asm-parisc/semaphore.h +++ b/include/asm-parisc/semaphore.h @@ -1,145 +1 @@ -/* SMP- and interrupt-safe semaphores. - * PA-RISC version by Matthew Wilcox - * - * Linux/PA-RISC Project (http://www.parisc-linux.org/) - * Copyright (C) 1996 Linus Torvalds - * Copyright (C) 1999-2001 Matthew Wilcox < willy at debian d0T org > - * Copyright (C) 2000 Grant Grundler < grundler a debian org > - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License as published by - * the Free Software Foundation; either version 2 of the License, or - * (at your option) any later version. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - * You should have received a copy of the GNU General Public License - * along with this program; if not, write to the Free Software - * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA - */ - -#ifndef _ASM_PARISC_SEMAPHORE_H -#define _ASM_PARISC_SEMAPHORE_H - -#include -#include -#include - -#include - -/* - * The `count' is initialised to the number of people who are allowed to - * take the lock. (Normally we want a mutex, so this is `1'). if - * `count' is positive, the lock can be taken. if it's 0, no-one is - * waiting on it. if it's -1, at least one task is waiting. - */ -struct semaphore { - spinlock_t sentry; - int count; - wait_queue_head_t wait; -}; - -#define __SEMAPHORE_INITIALIZER(name, n) \ -{ \ - .sentry = SPIN_LOCK_UNLOCKED, \ - .count = n, \ - .wait = __WAIT_QUEUE_HEAD_INITIALIZER((name).wait) \ -} - -#define __DECLARE_SEMAPHORE_GENERIC(name,count) \ - struct semaphore name = __SEMAPHORE_INITIALIZER(name,count) - -#define DECLARE_MUTEX(name) __DECLARE_SEMAPHORE_GENERIC(name,1) - -static inline void sema_init (struct semaphore *sem, int val) -{ - *sem = (struct semaphore)__SEMAPHORE_INITIALIZER((*sem),val); -} - -static inline void init_MUTEX (struct semaphore *sem) -{ - sema_init(sem, 1); -} - -static inline void init_MUTEX_LOCKED (struct semaphore *sem) -{ - sema_init(sem, 0); -} - -static inline int sem_getcount(struct semaphore *sem) -{ - return sem->count; -} - -asmlinkage void __down(struct semaphore * sem); -asmlinkage int __down_interruptible(struct semaphore * sem); -asmlinkage void __up(struct semaphore * sem); - -/* Semaphores can be `tried' from irq context. So we have to disable - * interrupts while we're messing with the semaphore. Sorry. - */ - -static inline void down(struct semaphore * sem) -{ - might_sleep(); - spin_lock_irq(&sem->sentry); - if (sem->count > 0) { - sem->count--; - } else { - __down(sem); - } - spin_unlock_irq(&sem->sentry); -} - -static inline int down_interruptible(struct semaphore * sem) -{ - int ret = 0; - might_sleep(); - spin_lock_irq(&sem->sentry); - if (sem->count > 0) { - sem->count--; - } else { - ret = __down_interruptible(sem); - } - spin_unlock_irq(&sem->sentry); - return ret; -} - -/* - * down_trylock returns 0 on success, 1 if we failed to get the lock. - * May not sleep, but must preserve irq state - */ -static inline int down_trylock(struct semaphore * sem) -{ - unsigned long flags; - int count; - - spin_lock_irqsave(&sem->sentry, flags); - count = sem->count - 1; - if (count >= 0) - sem->count = count; - spin_unlock_irqrestore(&sem->sentry, flags); - return (count < 0); -} - -/* - * Note! This is subtle. We jump to wake people up only if - * the semaphore was negative (== somebody was waiting on it). - */ -static inline void up(struct semaphore * sem) -{ - unsigned long flags; - - spin_lock_irqsave(&sem->sentry, flags); - if (sem->count < 0) { - __up(sem); - } else { - sem->count++; - } - spin_unlock_irqrestore(&sem->sentry, flags); -} - -#endif /* _ASM_PARISC_SEMAPHORE_H */ +#include diff --git a/include/asm-powerpc/semaphore.h b/include/asm-powerpc/semaphore.h index 48dd32e077..d9b2034ed1 100644 --- a/include/asm-powerpc/semaphore.h +++ b/include/asm-powerpc/semaphore.h @@ -1,94 +1 @@ -#ifndef _ASM_POWERPC_SEMAPHORE_H -#define _ASM_POWERPC_SEMAPHORE_H - -/* - * Remove spinlock-based RW semaphores; RW semaphore definitions are - * now in rwsem.h and we use the generic lib/rwsem.c implementation. - * Rework semaphores to use atomic_dec_if_positive. - * -- Paul Mackerras (paulus@samba.org) - */ - -#ifdef __KERNEL__ - -#include -#include -#include -#include - -struct semaphore { - /* - * Note that any negative value of count is equivalent to 0, - * but additionally indicates that some process(es) might be - * sleeping on `wait'. - */ - atomic_t count; - wait_queue_head_t wait; -}; - -#define __SEMAPHORE_INITIALIZER(name, n) \ -{ \ - .count = ATOMIC_INIT(n), \ - .wait = __WAIT_QUEUE_HEAD_INITIALIZER((name).wait) \ -} - -#define __DECLARE_SEMAPHORE_GENERIC(name, count) \ - struct semaphore name = __SEMAPHORE_INITIALIZER(name,count) - -#define DECLARE_MUTEX(name) __DECLARE_SEMAPHORE_GENERIC(name, 1) - -static inline void sema_init (struct semaphore *sem, int val) -{ - atomic_set(&sem->count, val); - init_waitqueue_head(&sem->wait); -} - -static inline void init_MUTEX (struct semaphore *sem) -{ - sema_init(sem, 1); -} - -static inline void init_MUTEX_LOCKED (struct semaphore *sem) -{ - sema_init(sem, 0); -} - -extern void __down(struct semaphore * sem); -extern int __down_interruptible(struct semaphore * sem); -extern void __up(struct semaphore * sem); - -static inline void down(struct semaphore * sem) -{ - might_sleep(); - - /* - * Try to get the semaphore, take the slow path if we fail. - */ - if (unlikely(atomic_dec_return(&sem->count) < 0)) - __down(sem); -} - -static inline int down_interruptible(struct semaphore * sem) -{ - int ret = 0; - - might_sleep(); - - if (unlikely(atomic_dec_return(&sem->count) < 0)) - ret = __down_interruptible(sem); - return ret; -} - -static inline int down_trylock(struct semaphore * sem) -{ - return atomic_dec_if_positive(&sem->count) < 0; -} - -static inline void up(struct semaphore * sem) -{ - if (unlikely(atomic_inc_return(&sem->count) <= 0)) - __up(sem); -} - -#endif /* __KERNEL__ */ - -#endif /* _ASM_POWERPC_SEMAPHORE_H */ +#include diff --git a/include/asm-s390/semaphore.h b/include/asm-s390/semaphore.h index 0e7001ad83..d9b2034ed1 100644 --- a/include/asm-s390/semaphore.h +++ b/include/asm-s390/semaphore.h @@ -1,107 +1 @@ -/* - * include/asm-s390/semaphore.h - * - * S390 version - * Copyright (C) 1999 IBM Deutschland Entwicklung GmbH, IBM Corporation - * - * Derived from "include/asm-i386/semaphore.h" - * (C) Copyright 1996 Linus Torvalds - */ - -#ifndef _S390_SEMAPHORE_H -#define _S390_SEMAPHORE_H - -#include -#include -#include -#include - -struct semaphore { - /* - * Note that any negative value of count is equivalent to 0, - * but additionally indicates that some process(es) might be - * sleeping on `wait'. - */ - atomic_t count; - wait_queue_head_t wait; -}; - -#define __SEMAPHORE_INITIALIZER(name,count) \ - { ATOMIC_INIT(count), __WAIT_QUEUE_HEAD_INITIALIZER((name).wait) } - -#define __DECLARE_SEMAPHORE_GENERIC(name,count) \ - struct semaphore name = __SEMAPHORE_INITIALIZER(name,count) - -#define DECLARE_MUTEX(name) __DECLARE_SEMAPHORE_GENERIC(name,1) - -static inline void sema_init (struct semaphore *sem, int val) -{ - atomic_set(&sem->count, val); - init_waitqueue_head(&sem->wait); -} - -static inline void init_MUTEX (struct semaphore *sem) -{ - sema_init(sem, 1); -} - -static inline void init_MUTEX_LOCKED (struct semaphore *sem) -{ - sema_init(sem, 0); -} - -asmlinkage void __down(struct semaphore * sem); -asmlinkage int __down_interruptible(struct semaphore * sem); -asmlinkage int __down_trylock(struct semaphore * sem); -asmlinkage void __up(struct semaphore * sem); - -static inline void down(struct semaphore * sem) -{ - might_sleep(); - if (atomic_dec_return(&sem->count) < 0) - __down(sem); -} - -static inline int down_interruptible(struct semaphore * sem) -{ - int ret = 0; - - might_sleep(); - if (atomic_dec_return(&sem->count) < 0) - ret = __down_interruptible(sem); - return ret; -} - -static inline int down_trylock(struct semaphore * sem) -{ - int old_val, new_val; - - /* - * This inline assembly atomically implements the equivalent - * to the following C code: - * old_val = sem->count.counter; - * if ((new_val = old_val) > 0) - * sem->count.counter = --new_val; - * In the ppc code this is called atomic_dec_if_positive. - */ - asm volatile( - " l %0,0(%3)\n" - "0: ltr %1,%0\n" - " jle 1f\n" - " ahi %1,-1\n" - " cs %0,%1,0(%3)\n" - " jl 0b\n" - "1:" - : "=&d" (old_val), "=&d" (new_val), "=m" (sem->count.counter) - : "a" (&sem->count.counter), "m" (sem->count.counter) - : "cc", "memory"); - return old_val <= 0; -} - -static inline void up(struct semaphore * sem) -{ - if (atomic_inc_return(&sem->count) <= 0) - __up(sem); -} - -#endif +#include diff --git a/include/asm-sh/semaphore-helper.h b/include/asm-sh/semaphore-helper.h deleted file mode 100644 index bd8230c369..0000000000 --- a/include/asm-sh/semaphore-helper.h +++ /dev/null @@ -1,89 +0,0 @@ -#ifndef __ASM_SH_SEMAPHORE_HELPER_H -#define __ASM_SH_SEMAPHORE_HELPER_H - -/* - * SMP- and interrupt-safe semaphores helper functions. - * - * (C) Copyright 1996 Linus Torvalds - * (C) Copyright 1999 Andrea Arcangeli - */ - -/* - * These two _must_ execute atomically wrt each other. - * - * This is trivially done with load_locked/store_cond, - * which we have. Let the rest of the losers suck eggs. - */ -static __inline__ void wake_one_more(struct semaphore * sem) -{ - atomic_inc((atomic_t *)&sem->sleepers); -} - -static __inline__ int waking_non_zero(struct semaphore *sem) -{ - unsigned long flags; - int ret = 0; - - spin_lock_irqsave(&semaphore_wake_lock, flags); - if (sem->sleepers > 0) { - sem->sleepers--; - ret = 1; - } - spin_unlock_irqrestore(&semaphore_wake_lock, flags); - return ret; -} - -/* - * waking_non_zero_interruptible: - * 1 got the lock - * 0 go to sleep - * -EINTR interrupted - * - * We must undo the sem->count down_interruptible() increment while we are - * protected by the spinlock in order to make atomic this atomic_inc() with the - * atomic_read() in wake_one_more(), otherwise we can race. -arca - */ -static __inline__ int waking_non_zero_interruptible(struct semaphore *sem, - struct task_struct *tsk) -{ - unsigned long flags; - int ret = 0; - - spin_lock_irqsave(&semaphore_wake_lock, flags); - if (sem->sleepers > 0) { - sem->sleepers--; - ret = 1; - } else if (signal_pending(tsk)) { - atomic_inc(&sem->count); - ret = -EINTR; - } - spin_unlock_irqrestore(&semaphore_wake_lock, flags); - return ret; -} - -/* - * waking_non_zero_trylock: - * 1 failed to lock - * 0 got the lock - * - * We must undo the sem->count down_trylock() increment while we are - * protected by the spinlock in order to make atomic this atomic_inc() with the - * atomic_read() in wake_one_more(), otherwise we can race. -arca - */ -static __inline__ int waking_non_zero_trylock(struct semaphore *sem) -{ - unsigned long flags; - int ret = 1; - - spin_lock_irqsave(&semaphore_wake_lock, flags); - if (sem->sleepers <= 0) - atomic_inc(&sem->count); - else { - sem->sleepers--; - ret = 0; - } - spin_unlock_irqrestore(&semaphore_wake_lock, flags); - return ret; -} - -#endif /* __ASM_SH_SEMAPHORE_HELPER_H */ diff --git a/include/asm-sh/semaphore.h b/include/asm-sh/semaphore.h index 9e5a37c4dc..d9b2034ed1 100644 --- a/include/asm-sh/semaphore.h +++ b/include/asm-sh/semaphore.h @@ -1,115 +1 @@ -#ifndef __ASM_SH_SEMAPHORE_H -#define __ASM_SH_SEMAPHORE_H - -#include - -#ifdef __KERNEL__ -/* - * SMP- and interrupt-safe semaphores. - * - * (C) Copyright 1996 Linus Torvalds - * - * SuperH verison by Niibe Yutaka - * (Currently no asm implementation but generic C code...) - */ - -#include -#include -#include - -#include -#include - -struct semaphore { - atomic_t count; - int sleepers; - wait_queue_head_t wait; -}; - -#define __SEMAPHORE_INITIALIZER(name, n) \ -{ \ - .count = ATOMIC_INIT(n), \ - .sleepers = 0, \ - .wait = __WAIT_QUEUE_HEAD_INITIALIZER((name).wait) \ -} - -#define __DECLARE_SEMAPHORE_GENERIC(name,count) \ - struct semaphore name = __SEMAPHORE_INITIALIZER(name,count) - -#define DECLARE_MUTEX(name) __DECLARE_SEMAPHORE_GENERIC(name,1) - -static inline void sema_init (struct semaphore *sem, int val) -{ -/* - * *sem = (struct semaphore)__SEMAPHORE_INITIALIZER((*sem),val); - * - * i'd rather use the more flexible initialization above, but sadly - * GCC 2.7.2.3 emits a bogus warning. EGCS doesn't. Oh well. - */ - atomic_set(&sem->count, val); - sem->sleepers = 0; - init_waitqueue_head(&sem->wait); -} - -static inline void init_MUTEX (struct semaphore *sem) -{ - sema_init(sem, 1); -} - -static inline void init_MUTEX_LOCKED (struct semaphore *sem) -{ - sema_init(sem, 0); -} - -#if 0 -asmlinkage void __down_failed(void /* special register calling convention */); -asmlinkage int __down_failed_interruptible(void /* params in registers */); -asmlinkage int __down_failed_trylock(void /* params in registers */); -asmlinkage void __up_wakeup(void /* special register calling convention */); -#endif - -asmlinkage void __down(struct semaphore * sem); -asmlinkage int __down_interruptible(struct semaphore * sem); -asmlinkage int __down_trylock(struct semaphore * sem); -asmlinkage void __up(struct semaphore * sem); - -extern spinlock_t semaphore_wake_lock; - -static inline void down(struct semaphore * sem) -{ - might_sleep(); - if (atomic_dec_return(&sem->count) < 0) - __down(sem); -} - -static inline int down_interruptible(struct semaphore * sem) -{ - int ret = 0; - - might_sleep(); - if (atomic_dec_return(&sem->count) < 0) - ret = __down_interruptible(sem); - return ret; -} - -static inline int down_trylock(struct semaphore * sem) -{ - int ret = 0; - - if (atomic_dec_return(&sem->count) < 0) - ret = __down_trylock(sem); - return ret; -} - -/* - * Note! This is subtle. We jump to wake people up only if - * the semaphore was negative (== somebody was waiting on it). - */ -static inline void up(struct semaphore * sem) -{ - if (atomic_inc_return(&sem->count) <= 0) - __up(sem); -} - -#endif -#endif /* __ASM_SH_SEMAPHORE_H */ +#include diff --git a/include/asm-sparc/semaphore.h b/include/asm-sparc/semaphore.h index 8018f9f4d4..d9b2034ed1 100644 --- a/include/asm-sparc/semaphore.h +++ b/include/asm-sparc/semaphore.h @@ -1,192 +1 @@ -#ifndef _SPARC_SEMAPHORE_H -#define _SPARC_SEMAPHORE_H - -/* Dinky, good for nothing, just barely irq safe, Sparc semaphores. */ - -#ifdef __KERNEL__ - -#include -#include -#include - -struct semaphore { - atomic24_t count; - int sleepers; - wait_queue_head_t wait; -}; - -#define __SEMAPHORE_INITIALIZER(name, n) \ -{ \ - .count = ATOMIC24_INIT(n), \ - .sleepers = 0, \ - .wait = __WAIT_QUEUE_HEAD_INITIALIZER((name).wait) \ -} - -#define __DECLARE_SEMAPHORE_GENERIC(name,count) \ - struct semaphore name = __SEMAPHORE_INITIALIZER(name,count) - -#define DECLARE_MUTEX(name) __DECLARE_SEMAPHORE_GENERIC(name,1) - -static inline void sema_init (struct semaphore *sem, int val) -{ - atomic24_set(&sem->count, val); - sem->sleepers = 0; - init_waitqueue_head(&sem->wait); -} - -static inline void init_MUTEX (struct semaphore *sem) -{ - sema_init(sem, 1); -} - -static inline void init_MUTEX_LOCKED (struct semaphore *sem) -{ - sema_init(sem, 0); -} - -extern void __down(struct semaphore * sem); -extern int __down_interruptible(struct semaphore * sem); -extern int __down_trylock(struct semaphore * sem); -extern void __up(struct semaphore * sem); - -static inline void down(struct semaphore * sem) -{ - register volatile int *ptr asm("g1"); - register int increment asm("g2"); - - might_sleep(); - - ptr = &(sem->count.counter); - increment = 1; - - __asm__ __volatile__( - "mov %%o7, %%g4\n\t" - "call ___atomic24_sub\n\t" - " add %%o7, 8, %%o7\n\t" - "tst %%g2\n\t" - "bl 2f\n\t" - " nop\n" - "1:\n\t" - ".subsection 2\n" - "2:\n\t" - "save %%sp, -64, %%sp\n\t" - "mov %%g1, %%l1\n\t" - "mov %%g5, %%l5\n\t" - "call %3\n\t" - " mov %%g1, %%o0\n\t" - "mov %%l1, %%g1\n\t" - "ba 1b\n\t" - " restore %%l5, %%g0, %%g5\n\t" - ".previous\n" - : "=&r" (increment) - : "0" (increment), "r" (ptr), "i" (__down) - : "g3", "g4", "g7", "memory", "cc"); -} - -static inline int down_interruptible(struct semaphore * sem) -{ - register volatile int *ptr asm("g1"); - register int increment asm("g2"); - - might_sleep(); - - ptr = &(sem->count.counter); - increment = 1; - - __asm__ __volatile__( - "mov %%o7, %%g4\n\t" - "call ___atomic24_sub\n\t" - " add %%o7, 8, %%o7\n\t" - "tst %%g2\n\t" - "bl 2f\n\t" - " clr %%g2\n" - "1:\n\t" - ".subsection 2\n" - "2:\n\t" - "save %%sp, -64, %%sp\n\t" - "mov %%g1, %%l1\n\t" - "mov %%g5, %%l5\n\t" - "call %3\n\t" - " mov %%g1, %%o0\n\t" - "mov %%l1, %%g1\n\t" - "mov %%l5, %%g5\n\t" - "ba 1b\n\t" - " restore %%o0, %%g0, %%g2\n\t" - ".previous\n" - : "=&r" (increment) - : "0" (increment), "r" (ptr), "i" (__down_interruptible) - : "g3", "g4", "g7", "memory", "cc"); - - return increment; -} - -static inline int down_trylock(struct semaphore * sem) -{ - register volatile int *ptr asm("g1"); - register int increment asm("g2"); - - ptr = &(sem->count.counter); - increment = 1; - - __asm__ __volatile__( - "mov %%o7, %%g4\n\t" - "call ___atomic24_sub\n\t" - " add %%o7, 8, %%o7\n\t" - "tst %%g2\n\t" - "bl 2f\n\t" - " clr %%g2\n" - "1:\n\t" - ".subsection 2\n" - "2:\n\t" - "save %%sp, -64, %%sp\n\t" - "mov %%g1, %%l1\n\t" - "mov %%g5, %%l5\n\t" - "call %3\n\t" - " mov %%g1, %%o0\n\t" - "mov %%l1, %%g1\n\t" - "mov %%l5, %%g5\n\t" - "ba 1b\n\t" - " restore %%o0, %%g0, %%g2\n\t" - ".previous\n" - : "=&r" (increment) - : "0" (increment), "r" (ptr), "i" (__down_trylock) - : "g3", "g4", "g7", "memory", "cc"); - - return increment; -} - -static inline void up(struct semaphore * sem) -{ - register volatile int *ptr asm("g1"); - register int increment asm("g2"); - - ptr = &(sem->count.counter); - increment = 1; - - __asm__ __volatile__( - "mov %%o7, %%g4\n\t" - "call ___atomic24_add\n\t" - " add %%o7, 8, %%o7\n\t" - "tst %%g2\n\t" - "ble 2f\n\t" - " nop\n" - "1:\n\t" - ".subsection 2\n" - "2:\n\t" - "save %%sp, -64, %%sp\n\t" - "mov %%g1, %%l1\n\t" - "mov %%g5, %%l5\n\t" - "call %3\n\t" - " mov %%g1, %%o0\n\t" - "mov %%l1, %%g1\n\t" - "ba 1b\n\t" - " restore %%l5, %%g0, %%g5\n\t" - ".previous\n" - : "=&r" (increment) - : "0" (increment), "r" (ptr), "i" (__up) - : "g3", "g4", "g7", "memory", "cc"); -} - -#endif /* __KERNEL__ */ - -#endif /* !(_SPARC_SEMAPHORE_H) */ +#include diff --git a/include/asm-sparc64/semaphore.h b/include/asm-sparc64/semaphore.h index 7f7c0c4e02..d9b2034ed1 100644 --- a/include/asm-sparc64/semaphore.h +++ b/include/asm-sparc64/semaphore.h @@ -1,53 +1 @@ -#ifndef _SPARC64_SEMAPHORE_H -#define _SPARC64_SEMAPHORE_H - -/* These are actually reasonable on the V9. - * - * See asm-ppc/semaphore.h for implementation commentary, - * only sparc64 specific issues are commented here. - */ -#ifdef __KERNEL__ - -#include -#include -#include -#include - -struct semaphore { - atomic_t count; - wait_queue_head_t wait; -}; - -#define __SEMAPHORE_INITIALIZER(name, count) \ - { ATOMIC_INIT(count), \ - __WAIT_QUEUE_HEAD_INITIALIZER((name).wait) } - -#define __DECLARE_SEMAPHORE_GENERIC(name, count) \ - struct semaphore name = __SEMAPHORE_INITIALIZER(name,count) - -#define DECLARE_MUTEX(name) __DECLARE_SEMAPHORE_GENERIC(name, 1) - -static inline void sema_init (struct semaphore *sem, int val) -{ - atomic_set(&sem->count, val); - init_waitqueue_head(&sem->wait); -} - -static inline void init_MUTEX (struct semaphore *sem) -{ - sema_init(sem, 1); -} - -static inline void init_MUTEX_LOCKED (struct semaphore *sem) -{ - sema_init(sem, 0); -} - -extern void up(struct semaphore *sem); -extern void down(struct semaphore *sem); -extern int down_trylock(struct semaphore *sem); -extern int down_interruptible(struct semaphore *sem); - -#endif /* __KERNEL__ */ - -#endif /* !(_SPARC64_SEMAPHORE_H) */ +#include diff --git a/include/asm-um/semaphore.h b/include/asm-um/semaphore.h index ff13c34de4..d9b2034ed1 100644 --- a/include/asm-um/semaphore.h +++ b/include/asm-um/semaphore.h @@ -1,6 +1 @@ -#ifndef __UM_SEMAPHORE_H -#define __UM_SEMAPHORE_H - -#include "asm/arch/semaphore.h" - -#endif +#include diff --git a/include/asm-v850/semaphore.h b/include/asm-v850/semaphore.h index 10ed0ccf37..d9b2034ed1 100644 --- a/include/asm-v850/semaphore.h +++ b/include/asm-v850/semaphore.h @@ -1,84 +1 @@ -#ifndef __V850_SEMAPHORE_H__ -#define __V850_SEMAPHORE_H__ - -#include -#include -#include -#include - -#include - -struct semaphore { - atomic_t count; - int sleepers; - wait_queue_head_t wait; -}; - -#define __SEMAPHORE_INITIALIZER(name,count) \ - { ATOMIC_INIT (count), 0, \ - __WAIT_QUEUE_HEAD_INITIALIZER ((name).wait) } - -#define __DECLARE_SEMAPHORE_GENERIC(name,count) \ - struct semaphore name = __SEMAPHORE_INITIALIZER (name,count) - -#define DECLARE_MUTEX(name) __DECLARE_SEMAPHORE_GENERIC (name,1) - -static inline void sema_init (struct semaphore *sem, int val) -{ - *sem = (struct semaphore)__SEMAPHORE_INITIALIZER((*sem),val); -} - -static inline void init_MUTEX (struct semaphore *sem) -{ - sema_init (sem, 1); -} - -static inline void init_MUTEX_LOCKED (struct semaphore *sem) -{ - sema_init (sem, 0); -} - -/* - * special register calling convention - */ -asmlinkage void __down_failed (void); -asmlinkage int __down_interruptible_failed (void); -asmlinkage int __down_trylock_failed (void); -asmlinkage void __up_wakeup (void); - -extern void __down (struct semaphore * sem); -extern int __down_interruptible (struct semaphore * sem); -extern int __down_trylock (struct semaphore * sem); -extern void __up (struct semaphore * sem); - -static inline void down (struct semaphore * sem) -{ - might_sleep(); - if (atomic_dec_return (&sem->count) < 0) - __down (sem); -} - -static inline int down_interruptible (struct semaphore * sem) -{ - int ret = 0; - might_sleep(); - if (atomic_dec_return (&sem->count) < 0) - ret = __down_interruptible (sem); - return ret; -} - -static inline int down_trylock (struct semaphore *sem) -{ - int ret = 0; - if (atomic_dec_return (&sem->count) < 0) - ret = __down_trylock (sem); - return ret; -} - -static inline void up (struct semaphore * sem) -{ - if (atomic_inc_return (&sem->count) <= 0) - __up (sem); -} - -#endif /* __V850_SEMAPHORE_H__ */ +#include diff --git a/include/asm-x86/semaphore.h b/include/asm-x86/semaphore.h index 572c0b67a6..d9b2034ed1 100644 --- a/include/asm-x86/semaphore.h +++ b/include/asm-x86/semaphore.h @@ -1,5 +1 @@ -#ifdef CONFIG_X86_32 -# include "semaphore_32.h" -#else -# include "semaphore_64.h" -#endif +#include diff --git a/include/asm-x86/semaphore_32.h b/include/asm-x86/semaphore_32.h deleted file mode 100644 index ac96d3804d..0000000000 --- a/include/asm-x86/semaphore_32.h +++ /dev/null @@ -1,175 +0,0 @@ -#ifndef _I386_SEMAPHORE_H -#define _I386_SEMAPHORE_H - -#include - -#ifdef __KERNEL__ - -/* - * SMP- and interrupt-safe semaphores.. - * - * (C) Copyright 1996 Linus Torvalds - * - * Modified 1996-12-23 by Dave Grothe to fix bugs in - * the original code and to make semaphore waits - * interruptible so that processes waiting on - * semaphores can be killed. - * Modified 1999-02-14 by Andrea Arcangeli, split the sched.c helper - * functions in asm/sempahore-helper.h while fixing a - * potential and subtle race discovered by Ulrich Schmid - * in down_interruptible(). Since I started to play here I - * also implemented the `trylock' semaphore operation. - * 1999-07-02 Artur Skawina - * Optimized "0(ecx)" -> "(ecx)" (the assembler does not - * do this). Changed calling sequences from push/jmp to - * traditional call/ret. - * Modified 2001-01-01 Andreas Franck - * Some hacks to ensure compatibility with recent - * GCC snapshots, to avoid stack corruption when compiling - * with -fomit-frame-pointer. It's not sure if this will - * be fixed in GCC, as our previous implementation was a - * bit dubious. - * - * If you would like to see an analysis of this implementation, please - * ftp to gcom.com and download the file - * /pub/linux/src/semaphore/semaphore-2.0.24.tar.gz. - * - */ - -#include -#include -#include -#include - -struct semaphore { - atomic_t count; - int sleepers; - wait_queue_head_t wait; -}; - - -#define __SEMAPHORE_INITIALIZER(name, n) \ -{ \ - .count = ATOMIC_INIT(n), \ - .sleepers = 0, \ - .wait = __WAIT_QUEUE_HEAD_INITIALIZER((name).wait) \ -} - -#define __DECLARE_SEMAPHORE_GENERIC(name,count) \ - struct semaphore name = __SEMAPHORE_INITIALIZER(name,count) - -#define DECLARE_MUTEX(name) __DECLARE_SEMAPHORE_GENERIC(name,1) - -static inline void sema_init (struct semaphore *sem, int val) -{ -/* - * *sem = (struct semaphore)__SEMAPHORE_INITIALIZER((*sem),val); - * - * i'd rather use the more flexible initialization above, but sadly - * GCC 2.7.2.3 emits a bogus warning. EGCS doesn't. Oh well. - */ - atomic_set(&sem->count, val); - sem->sleepers = 0; - init_waitqueue_head(&sem->wait); -} - -static inline void init_MUTEX (struct semaphore *sem) -{ - sema_init(sem, 1); -} - -static inline void init_MUTEX_LOCKED (struct semaphore *sem) -{ - sema_init(sem, 0); -} - -extern asmregparm void __down_failed(atomic_t *count_ptr); -extern asmregparm int __down_failed_interruptible(atomic_t *count_ptr); -extern asmregparm int __down_failed_trylock(atomic_t *count_ptr); -extern asmregparm void __up_wakeup(atomic_t *count_ptr); - -/* - * This is ugly, but we want the default case to fall through. - * "__down_failed" is a special asm handler that calls the C - * routine that actually waits. See arch/i386/kernel/semaphore.c - */ -static inline void down(struct semaphore * sem) -{ - might_sleep(); - __asm__ __volatile__( - "# atomic down operation\n\t" - LOCK_PREFIX "decl %0\n\t" /* --sem->count */ - "jns 2f\n" - "\tlea %0,%%eax\n\t" - "call __down_failed\n" - "2:" - :"+m" (sem->count) - : - :"memory","ax"); -} - -/* - * Interruptible try to acquire a semaphore. If we obtained - * it, return zero. If we were interrupted, returns -EINTR - */ -static inline int down_interruptible(struct semaphore * sem) -{ - int result; - - might_sleep(); - __asm__ __volatile__( - "# atomic interruptible down operation\n\t" - "xorl %0,%0\n\t" - LOCK_PREFIX "decl %1\n\t" /* --sem->count */ - "jns 2f\n\t" - "lea %1,%%eax\n\t" - "call __down_failed_interruptible\n" - "2:" - :"=&a" (result), "+m" (sem->count) - : - :"memory"); - return result; -} - -/* - * Non-blockingly attempt to down() a semaphore. - * Returns zero if we acquired it - */ -static inline int down_trylock(struct semaphore * sem) -{ - int result; - - __asm__ __volatile__( - "# atomic interruptible down operation\n\t" - "xorl %0,%0\n\t" - LOCK_PREFIX "decl %1\n\t" /* --sem->count */ - "jns 2f\n\t" - "lea %1,%%eax\n\t" - "call __down_failed_trylock\n\t" - "2:\n" - :"=&a" (result), "+m" (sem->count) - : - :"memory"); - return result; -} - -/* - * Note! This is subtle. We jump to wake people up only if - * the semaphore was negative (== somebody was waiting on it). - */ -static inline void up(struct semaphore * sem) -{ - __asm__ __volatile__( - "# atomic up operation\n\t" - LOCK_PREFIX "incl %0\n\t" /* ++sem->count */ - "jg 1f\n\t" - "lea %0,%%eax\n\t" - "call __up_wakeup\n" - "1:" - :"+m" (sem->count) - : - :"memory","ax"); -} - -#endif -#endif diff --git a/include/asm-x86/semaphore_64.h b/include/asm-x86/semaphore_64.h deleted file mode 100644 index 79694306bf..0000000000 --- a/include/asm-x86/semaphore_64.h +++ /dev/null @@ -1,180 +0,0 @@ -#ifndef _X86_64_SEMAPHORE_H -#define _X86_64_SEMAPHORE_H - -#include - -#ifdef __KERNEL__ - -/* - * SMP- and interrupt-safe semaphores.. - * - * (C) Copyright 1996 Linus Torvalds - * - * Modified 1996-12-23 by Dave Grothe to fix bugs in - * the original code and to make semaphore waits - * interruptible so that processes waiting on - * semaphores can be killed. - * Modified 1999-02-14 by Andrea Arcangeli, split the sched.c helper - * functions in asm/sempahore-helper.h while fixing a - * potential and subtle race discovered by Ulrich Schmid - * in down_interruptible(). Since I started to play here I - * also implemented the `trylock' semaphore operation. - * 1999-07-02 Artur Skawina - * Optimized "0(ecx)" -> "(ecx)" (the assembler does not - * do this). Changed calling sequences from push/jmp to - * traditional call/ret. - * Modified 2001-01-01 Andreas Franck - * Some hacks to ensure compatibility with recent - * GCC snapshots, to avoid stack corruption when compiling - * with -fomit-frame-pointer. It's not sure if this will - * be fixed in GCC, as our previous implementation was a - * bit dubious. - * - * If you would like to see an analysis of this implementation, please - * ftp to gcom.com and download the file - * /pub/linux/src/semaphore/semaphore-2.0.24.tar.gz. - * - */ - -#include -#include -#include -#include -#include -#include - -struct semaphore { - atomic_t count; - int sleepers; - wait_queue_head_t wait; -}; - -#define __SEMAPHORE_INITIALIZER(name, n) \ -{ \ - .count = ATOMIC_INIT(n), \ - .sleepers = 0, \ - .wait = __WAIT_QUEUE_HEAD_INITIALIZER((name).wait) \ -} - -#define __DECLARE_SEMAPHORE_GENERIC(name,count) \ - struct semaphore name = __SEMAPHORE_INITIALIZER(name,count) - -#define DECLARE_MUTEX(name) __DECLARE_SEMAPHORE_GENERIC(name,1) - -static inline void sema_init (struct semaphore *sem, int val) -{ -/* - * *sem = (struct semaphore)__SEMAPHORE_INITIALIZER((*sem),val); - * - * i'd rather use the more flexible initialization above, but sadly - * GCC 2.7.2.3 emits a bogus warning. EGCS doesn't. Oh well. - */ - atomic_set(&sem->count, val); - sem->sleepers = 0; - init_waitqueue_head(&sem->wait); -} - -static inline void init_MUTEX (struct semaphore *sem) -{ - sema_init(sem, 1); -} - -static inline void init_MUTEX_LOCKED (struct semaphore *sem) -{ - sema_init(sem, 0); -} - -asmlinkage void __down_failed(void /* special register calling convention */); -asmlinkage int __down_failed_interruptible(void /* params in registers */); -asmlinkage int __down_failed_trylock(void /* params in registers */); -asmlinkage void __up_wakeup(void /* special register calling convention */); - -asmlinkage void __down(struct semaphore * sem); -asmlinkage int __down_interruptible(struct semaphore * sem); -asmlinkage int __down_trylock(struct semaphore * sem); -asmlinkage void __up(struct semaphore * sem); - -/* - * This is ugly, but we want the default case to fall through. - * "__down_failed" is a special asm handler that calls the C - * routine that actually waits. See arch/x86_64/kernel/semaphore.c - */ -static inline void down(struct semaphore * sem) -{ - might_sleep(); - - __asm__ __volatile__( - "# atomic down operation\n\t" - LOCK_PREFIX "decl %0\n\t" /* --sem->count */ - "jns 1f\n\t" - "call __down_failed\n" - "1:" - :"=m" (sem->count) - :"D" (sem) - :"memory"); -} - -/* - * Interruptible try to acquire a semaphore. If we obtained - * it, return zero. If we were interrupted, returns -EINTR - */ -static inline int down_interruptible(struct semaphore * sem) -{ - int result; - - might_sleep(); - - __asm__ __volatile__( - "# atomic interruptible down operation\n\t" - "xorl %0,%0\n\t" - LOCK_PREFIX "decl %1\n\t" /* --sem->count */ - "jns 2f\n\t" - "call __down_failed_interruptible\n" - "2:\n" - :"=&a" (result), "=m" (sem->count) - :"D" (sem) - :"memory"); - return result; -} - -/* - * Non-blockingly attempt to down() a semaphore. - * Returns zero if we acquired it - */ -static inline int down_trylock(struct semaphore * sem) -{ - int result; - - __asm__ __volatile__( - "# atomic interruptible down operation\n\t" - "xorl %0,%0\n\t" - LOCK_PREFIX "decl %1\n\t" /* --sem->count */ - "jns 2f\n\t" - "call __down_failed_trylock\n\t" - "2:\n" - :"=&a" (result), "=m" (sem->count) - :"D" (sem) - :"memory","cc"); - return result; -} - -/* - * Note! This is subtle. We jump to wake people up only if - * the semaphore was negative (== somebody was waiting on it). - * The default case (no contention) will result in NO - * jumps for both down() and up(). - */ -static inline void up(struct semaphore * sem) -{ - __asm__ __volatile__( - "# atomic up operation\n\t" - LOCK_PREFIX "incl %0\n\t" /* ++sem->count */ - "jg 1f\n\t" - "call __up_wakeup\n" - "1:" - :"=m" (sem->count) - :"D" (sem) - :"memory"); -} -#endif /* __KERNEL__ */ -#endif diff --git a/include/asm-xtensa/semaphore.h b/include/asm-xtensa/semaphore.h index 3e04167cd9..d9b2034ed1 100644 --- a/include/asm-xtensa/semaphore.h +++ b/include/asm-xtensa/semaphore.h @@ -1,99 +1 @@ -/* - * linux/include/asm-xtensa/semaphore.h - * - * This file is subject to the terms and conditions of the GNU General Public - * License. See the file "COPYING" in the main directory of this archive - * for more details. - * - * Copyright (C) 2001 - 2005 Tensilica Inc. - */ - -#ifndef _XTENSA_SEMAPHORE_H -#define _XTENSA_SEMAPHORE_H - -#include -#include -#include -#include - -struct semaphore { - atomic_t count; - int sleepers; - wait_queue_head_t wait; -}; - -#define __SEMAPHORE_INITIALIZER(name,n) \ -{ \ - .count = ATOMIC_INIT(n), \ - .sleepers = 0, \ - .wait = __WAIT_QUEUE_HEAD_INITIALIZER((name).wait) \ -} - -#define __DECLARE_SEMAPHORE_GENERIC(name,count) \ - struct semaphore name = __SEMAPHORE_INITIALIZER(name,count) - -#define DECLARE_MUTEX(name) __DECLARE_SEMAPHORE_GENERIC(name,1) - -static inline void sema_init (struct semaphore *sem, int val) -{ - atomic_set(&sem->count, val); - sem->sleepers = 0; - init_waitqueue_head(&sem->wait); -} - -static inline void init_MUTEX (struct semaphore *sem) -{ - sema_init(sem, 1); -} - -static inline void init_MUTEX_LOCKED (struct semaphore *sem) -{ - sema_init(sem, 0); -} - -asmlinkage void __down(struct semaphore * sem); -asmlinkage int __down_interruptible(struct semaphore * sem); -asmlinkage int __down_trylock(struct semaphore * sem); -asmlinkage void __up(struct semaphore * sem); - -extern spinlock_t semaphore_wake_lock; - -static inline void down(struct semaphore * sem) -{ - might_sleep(); - - if (atomic_sub_return(1, &sem->count) < 0) - __down(sem); -} - -static inline int down_interruptible(struct semaphore * sem) -{ - int ret = 0; - - might_sleep(); - - if (atomic_sub_return(1, &sem->count) < 0) - ret = __down_interruptible(sem); - return ret; -} - -static inline int down_trylock(struct semaphore * sem) -{ - int ret = 0; - - if (atomic_sub_return(1, &sem->count) < 0) - ret = __down_trylock(sem); - return ret; -} - -/* - * Note! This is subtle. We jump to wake people up only if - * the semaphore was negative (== somebody was waiting on it). - */ -static inline void up(struct semaphore * sem) -{ - if (atomic_add_return(1, &sem->count) <= 0) - __up(sem); -} - -#endif /* _XTENSA_SEMAPHORE_H */ +#include diff --git a/include/linux/semaphore.h b/include/linux/semaphore.h new file mode 100644 index 0000000000..b3c691b089 --- /dev/null +++ b/include/linux/semaphore.h @@ -0,0 +1,77 @@ +/* + * Copyright (c) 2008 Intel Corporation + * Author: Matthew Wilcox + * + * Distributed under the terms of the GNU GPL, version 2 + * + * Counting semaphores allow up to tasks to acquire the semaphore + * simultaneously. + */ +#ifndef __LINUX_SEMAPHORE_H +#define __LINUX_SEMAPHORE_H + +#include +#include + +/* + * The spinlock controls access to the other members of the semaphore. + * 'count' is decremented by every task which calls down*() and incremented + * by every call to up(). Thus, if it is positive, it indicates how many + * more tasks may acquire the lock. If it is negative, it indicates how + * many tasks are waiting for the lock. Tasks waiting for the lock are + * kept on the wait_list. + */ +struct semaphore { + spinlock_t lock; + int count; + struct list_head wait_list; +}; + +#define __SEMAPHORE_INITIALIZER(name, n) \ +{ \ + .lock = __SPIN_LOCK_UNLOCKED((name).lock), \ + .count = n, \ + .wait_list = LIST_HEAD_INIT((name).wait_list), \ +} + +#define __DECLARE_SEMAPHORE_GENERIC(name, count) \ + struct semaphore name = __SEMAPHORE_INITIALIZER(name, count) + +#define DECLARE_MUTEX(name) __DECLARE_SEMAPHORE_GENERIC(name, 1) + +static inline void sema_init(struct semaphore *sem, int val) +{ + static struct lock_class_key __key; + *sem = (struct semaphore) __SEMAPHORE_INITIALIZER(*sem, val); + lockdep_init_map(&sem->lock.dep_map, "semaphore->lock", &__key, 0); +} + +#define init_MUTEX(sem) sema_init(sem, 1) +#define init_MUTEX_LOCKED(sem) sema_init(sem, 0) + +/* + * Attempt to acquire the semaphore. If another task is already holding the + * semaphore, sleep until the semaphore is released. + */ +extern void down(struct semaphore *sem); + +/* + * As down(), except the sleep may be interrupted by a signal. If it is, + * this function will return -EINTR. + */ +extern int __must_check down_interruptible(struct semaphore *sem); + +/* + * As down(), except this function will not sleep. It will return 0 if it + * acquired the semaphore and 1 if the semaphore was contended. This + * function may be called from any context, including interrupt and softirq. + */ +extern int __must_check down_trylock(struct semaphore *sem); + +/* + * Release the semaphore. Unlike mutexes, up() may be called from any + * context and even by tasks which have never called down(). + */ +extern void up(struct semaphore *sem); + +#endif /* __LINUX_SEMAPHORE_H */ diff --git a/kernel/Makefile b/kernel/Makefile index 6c584c55a6..f45c69e696 100644 --- a/kernel/Makefile +++ b/kernel/Makefile @@ -8,7 +8,7 @@ obj-y = sched.o fork.o exec_domain.o panic.o printk.o profile.o \ signal.o sys.o kmod.o workqueue.o pid.o \ rcupdate.o extable.o params.o posix-timers.o \ kthread.o wait.o kfifo.o sys_ni.o posix-cpu-timers.o mutex.o \ - hrtimer.o rwsem.o nsproxy.o srcu.o \ + hrtimer.o rwsem.o nsproxy.o srcu.o semaphore.o \ notifier.o ksysfs.o pm_qos_params.o obj-$(CONFIG_SYSCTL) += sysctl_check.o diff --git a/kernel/semaphore.c b/kernel/semaphore.c new file mode 100644 index 0000000000..d5a72702f2 --- /dev/null +++ b/kernel/semaphore.c @@ -0,0 +1,187 @@ +/* + * Copyright (c) 2008 Intel Corporation + * Author: Matthew Wilcox + * + * Distributed under the terms of the GNU GPL, version 2 + */ + +#include +#include +#include +#include +#include +#include + +/* + * Some notes on the implementation: + * + * down_trylock() and up() can be called from interrupt context. + * So we have to disable interrupts when taking the lock. + * + * The ->count variable, if positive, defines how many more tasks can + * acquire the semaphore. If negative, it represents how many tasks are + * waiting on the semaphore (*). If zero, no tasks are waiting, and no more + * tasks can acquire the semaphore. + * + * (*) Except for the window between one task calling up() and the task + * sleeping in a __down_common() waking up. In order to avoid a third task + * coming in and stealing the second task's wakeup, we leave the ->count + * negative. If we have a more complex situation, the ->count may become + * zero or negative (eg a semaphore with count = 2, three tasks attempt to + * acquire it, one sleeps, two finish and call up(), the second task to call + * up() notices that the list is empty and just increments count). + */ + +static noinline void __down(struct semaphore *sem); +static noinline int __down_interruptible(struct semaphore *sem); +static noinline void __up(struct semaphore *sem); + +void down(struct semaphore *sem) +{ + unsigned long flags; + + spin_lock_irqsave(&sem->lock, flags); + if (unlikely(sem->count-- <= 0)) + __down(sem); + spin_unlock_irqrestore(&sem->lock, flags); +} +EXPORT_SYMBOL(down); + +int down_interruptible(struct semaphore *sem) +{ + unsigned long flags; + int result = 0; + + spin_lock_irqsave(&sem->lock, flags); + if (unlikely(sem->count-- <= 0)) + result = __down_interruptible(sem); + spin_unlock_irqrestore(&sem->lock, flags); + + return result; +} +EXPORT_SYMBOL(down_interruptible); + +/** + * down_trylock - try to acquire the semaphore, without waiting + * @sem: the semaphore to be acquired + * + * Try to acquire the semaphore atomically. Returns 0 if the mutex has + * been acquired successfully and 1 if it is contended. + * + * NOTE: This return value is inverted from both spin_trylock and + * mutex_trylock! Be careful about this when converting code. + * + * Unlike mutex_trylock, this function can be used from interrupt context, + * and the semaphore can be released by any task or interrupt. + */ +int down_trylock(struct semaphore *sem) +{ + unsigned long flags; + int count; + + spin_lock_irqsave(&sem->lock, flags); + count = sem->count - 1; + if (likely(count >= 0)) + sem->count = count; + spin_unlock_irqrestore(&sem->lock, flags); + + return (count < 0); +} +EXPORT_SYMBOL(down_trylock); + +void up(struct semaphore *sem) +{ + unsigned long flags; + + spin_lock_irqsave(&sem->lock, flags); + if (likely(sem->count >= 0)) + sem->count++; + else + __up(sem); + spin_unlock_irqrestore(&sem->lock, flags); +} +EXPORT_SYMBOL(up); + +/* Functions for the contended case */ + +struct semaphore_waiter { + struct list_head list; + struct task_struct *task; + int up; +}; + +/* + * Wake up a process waiting on a semaphore. We need to call this from both + * __up and __down_common as it's possible to race a task into the semaphore + * if it comes in at just the right time between two tasks calling up() and + * a third task waking up. This function assumes the wait_list is already + * checked for being non-empty. + */ +static noinline void __sched __up_down_common(struct semaphore *sem) +{ + struct semaphore_waiter *waiter = list_first_entry(&sem->wait_list, + struct semaphore_waiter, list); + list_del(&waiter->list); + waiter->up = 1; + wake_up_process(waiter->task); +} + +/* + * Because this function is inlined, the 'state' parameter will be constant, + * and thus optimised away by the compiler. + */ +static inline int __sched __down_common(struct semaphore *sem, long state) +{ + int result = 0; + struct task_struct *task = current; + struct semaphore_waiter waiter; + + list_add_tail(&waiter.list, &sem->wait_list); + waiter.task = task; + waiter.up = 0; + + for (;;) { + if (state == TASK_INTERRUPTIBLE && signal_pending(task)) + goto interrupted; + __set_task_state(task, state); + spin_unlock_irq(&sem->lock); + schedule(); + spin_lock_irq(&sem->lock); + if (waiter.up) + goto woken; + } + + interrupted: + list_del(&waiter.list); + result = -EINTR; + woken: + /* + * Account for the process which woke us up. For the case where + * we're interrupted, we need to increment the count on our own + * behalf. I don't believe we can hit the case where the + * sem->count hits zero, *and* there's a second task sleeping, + * but it doesn't hurt, that's not a commonly exercised path and + * it's not a performance path either. + */ + if (unlikely((++sem->count >= 0) && !list_empty(&sem->wait_list))) + __up_down_common(sem); + return result; +} + +static noinline void __sched __down(struct semaphore *sem) +{ + __down_common(sem, TASK_UNINTERRUPTIBLE); +} + +static noinline int __sched __down_interruptible(struct semaphore *sem) +{ + return __down_common(sem, TASK_INTERRUPTIBLE); +} + +static noinline void __sched __up(struct semaphore *sem) +{ + if (unlikely(list_empty(&sem->wait_list))) + sem->count++; + else + __up_down_common(sem); +} diff --git a/lib/Makefile b/lib/Makefile index 23de261a4c..28dba90d50 100644 --- a/lib/Makefile +++ b/lib/Makefile @@ -29,7 +29,6 @@ obj-$(CONFIG_DEBUG_LOCKING_API_SELFTESTS) += locking-selftest.o obj-$(CONFIG_DEBUG_SPINLOCK) += spinlock_debug.o lib-$(CONFIG_RWSEM_GENERIC_SPINLOCK) += rwsem-spinlock.o lib-$(CONFIG_RWSEM_XCHGADD_ALGORITHM) += rwsem.o -lib-$(CONFIG_SEMAPHORE_SLEEPERS) += semaphore-sleepers.o lib-$(CONFIG_GENERIC_FIND_NEXT_BIT) += find_next_bit.o obj-$(CONFIG_GENERIC_HWEIGHT) += hweight.o obj-$(CONFIG_LOCK_KERNEL) += kernel_lock.o diff --git a/lib/semaphore-sleepers.c b/lib/semaphore-sleepers.c deleted file mode 100644 index 0198782cda..0000000000 --- a/lib/semaphore-sleepers.c +++ /dev/null @@ -1,176 +0,0 @@ -/* - * i386 and x86-64 semaphore implementation. - * - * (C) Copyright 1999 Linus Torvalds - * - * Portions Copyright 1999 Red Hat, Inc. - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public License - * as published by the Free Software Foundation; either version - * 2 of the License, or (at your option) any later version. - * - * rw semaphores implemented November 1999 by Benjamin LaHaise - */ -#include -#include -#include -#include - -/* - * Semaphores are implemented using a two-way counter: - * The "count" variable is decremented for each process - * that tries to acquire the semaphore, while the "sleeping" - * variable is a count of such acquires. - * - * Notably, the inline "up()" and "down()" functions can - * efficiently test if they need to do any extra work (up - * needs to do something only if count was negative before - * the increment operation. - * - * "sleeping" and the contention routine ordering is protected - * by the spinlock in the semaphore's waitqueue head. - * - * Note that these functions are only called when there is - * contention on the lock, and as such all this is the - * "non-critical" part of the whole semaphore business. The - * critical part is the inline stuff in - * where we want to avoid any extra jumps and calls. - */ - -/* - * Logic: - * - only on a boundary condition do we need to care. When we go - * from a negative count to a non-negative, we wake people up. - * - when we go from a non-negative count to a negative do we - * (a) synchronize with the "sleeper" count and (b) make sure - * that we're on the wakeup list before we synchronize so that - * we cannot lose wakeup events. - */ - -void __up(struct semaphore *sem) -{ - wake_up(&sem->wait); -} - -void __sched __down(struct semaphore *sem) -{ - struct task_struct *tsk = current; - DECLARE_WAITQUEUE(wait, tsk); - unsigned long flags; - - tsk->state = TASK_UNINTERRUPTIBLE; - spin_lock_irqsave(&sem->wait.lock, flags); - add_wait_queue_exclusive_locked(&sem->wait, &wait); - - sem->sleepers++; - for (;;) { - int sleepers = sem->sleepers; - - /* - * Add "everybody else" into it. They aren't - * playing, because we own the spinlock in - * the wait_queue_head. - */ - if (!atomic_add_negative(sleepers - 1, &sem->count)) { - sem->sleepers = 0; - break; - } - sem->sleepers = 1; /* us - see -1 above */ - spin_unlock_irqrestore(&sem->wait.lock, flags); - - schedule(); - - spin_lock_irqsave(&sem->wait.lock, flags); - tsk->state = TASK_UNINTERRUPTIBLE; - } - remove_wait_queue_locked(&sem->wait, &wait); - wake_up_locked(&sem->wait); - spin_unlock_irqrestore(&sem->wait.lock, flags); - tsk->state = TASK_RUNNING; -} - -int __sched __down_interruptible(struct semaphore *sem) -{ - int retval = 0; - struct task_struct *tsk = current; - DECLARE_WAITQUEUE(wait, tsk); - unsigned long flags; - - tsk->state = TASK_INTERRUPTIBLE; - spin_lock_irqsave(&sem->wait.lock, flags); - add_wait_queue_exclusive_locked(&sem->wait, &wait); - - sem->sleepers++; - for (;;) { - int sleepers = sem->sleepers; - - /* - * With signals pending, this turns into - * the trylock failure case - we won't be - * sleeping, and we* can't get the lock as - * it has contention. Just correct the count - * and exit. - */ - if (signal_pending(current)) { - retval = -EINTR; - sem->sleepers = 0; - atomic_add(sleepers, &sem->count); - break; - } - - /* - * Add "everybody else" into it. They aren't - * playing, because we own the spinlock in - * wait_queue_head. The "-1" is because we're - * still hoping to get the semaphore. - */ - if (!atomic_add_negative(sleepers - 1, &sem->count)) { - sem->sleepers = 0; - break; - } - sem->sleepers = 1; /* us - see -1 above */ - spin_unlock_irqrestore(&sem->wait.lock, flags); - - schedule(); - - spin_lock_irqsave(&sem->wait.lock, flags); - tsk->state = TASK_INTERRUPTIBLE; - } - remove_wait_queue_locked(&sem->wait, &wait); - wake_up_locked(&sem->wait); - spin_unlock_irqrestore(&sem->wait.lock, flags); - - tsk->state = TASK_RUNNING; - return retval; -} - -/* - * Trylock failed - make sure we correct for - * having decremented the count. - * - * We could have done the trylock with a - * single "cmpxchg" without failure cases, - * but then it wouldn't work on a 386. - */ -int __down_trylock(struct semaphore *sem) -{ - int sleepers; - unsigned long flags; - - spin_lock_irqsave(&sem->wait.lock, flags); - sleepers = sem->sleepers + 1; - sem->sleepers = 0; - - /* - * Add "everybody else" and us into it. They aren't - * playing, because we own the spinlock in the - * wait_queue_head. - */ - if (!atomic_add_negative(sleepers, &sem->count)) { - wake_up_locked(&sem->wait); - } - - spin_unlock_irqrestore(&sem->wait.lock, flags); - return 1; -} -- 2.39.5