[PATCH] powerpc: Merge thread_info.h

Merge ppc32 and ppc64 versions of thread_info.h.  They were pretty
similar already, the chief changes are:

	- Instead of inline asm to implement current_thread_info(),
which needs to be different for ppc32 and ppc64, we use C with an
asm("r1") register variable.  gcc turns it into the same asm as we
used to have for both platforms.
	- We replace ppc32's 'local_flags' with the ppc64
'syscall_noerror' field.  The noerror flag was in fact the only thing
in the local_flags field anyway, so the ppc64 approach is simpler, and
means we only need a load-immediate/store instead of load/mask/store
when clearing the flag.
	- In readiness for 64k pages, when THREAD_SIZE will be less
than a page, ppc64 used kmalloc() rather than get_free_pages() to
allocate the kernel stack.  With this patch we do the same for ppc32,
since there's no strong reason not to.
	- For ppc64, we no longer export THREAD_SHIFT and THREAD_SIZE
via asm-offsets, thread_info.h can now be safely included in asm, as
on ppc32.

Built and booted on G4 Powerbook (ARCH=ppc and ARCH=powerpc) and
Power5 (ARCH=ppc64 and ARCH=powerpc).

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>

diff --git a/arch/powerpc/kernel/asm-offsets.c b/arch/powerpc/kernel/asm-offsets.c
index b0d6a7cd85e9dceb2590978b13dc547560bb5810..1c83abd9f37cf699f49ed6c448a9b99be84a2786 100644 (file)
--- a/arch/powerpc/kernel/asm-offsets.c
+++ b/arch/powerpc/kernel/asm-offsets.c
@@ -56,8 +56,6 @@ int main(void)
        DEFINE(THREAD, offsetof(struct task_struct, thread));
        DEFINE(MM, offsetof(struct task_struct, mm));
 #ifdef CONFIG_PPC64
-       DEFINE(THREAD_SHIFT, THREAD_SHIFT);
-       DEFINE(THREAD_SIZE, THREAD_SIZE);
        DEFINE(AUDITCONTEXT, offsetof(struct task_struct, audit_context));
 #else
        DEFINE(THREAD_INFO, offsetof(struct task_struct, thread_info));
@@ -94,12 +92,10 @@ int main(void)
 
        DEFINE(TI_FLAGS, offsetof(struct thread_info, flags));
        DEFINE(TI_PREEMPT, offsetof(struct thread_info, preempt_count));
-#ifdef CONFIG_PPC64
        DEFINE(TI_SC_NOERR, offsetof(struct thread_info, syscall_noerror));
-#else
+#ifdef CONFIG_PPC32
        DEFINE(TI_TASK, offsetof(struct thread_info, task));
        DEFINE(TI_EXECDOMAIN, offsetof(struct thread_info, exec_domain));
-       DEFINE(TI_LOCAL_FLAGS, offsetof(struct thread_info, local_flags));
        DEFINE(TI_CPU, offsetof(struct thread_info, cpu));
 #endif /* CONFIG_PPC64 */
 

diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S
index fc9dded9ac045d14522629efecda9d778914e52a..37b4396ca97860b5ed4acc2caa27de824a2fdba4 100644 (file)
--- a/arch/powerpc/kernel/entry_32.S
+++ b/arch/powerpc/kernel/entry_32.S
@@ -199,10 +199,9 @@ _GLOBAL(DoSyscall)
 #ifdef SHOW_SYSCALLS
        bl      do_show_syscall
 #endif /* SHOW_SYSCALLS */
-       rlwinm  r10,r1,0,0,18   /* current_thread_info() */
-       lwz     r11,TI_LOCAL_FLAGS(r10)
-       rlwinm  r11,r11,0,~_TIFL_FORCE_NOERROR
-       stw     r11,TI_LOCAL_FLAGS(r10)
+       rlwinm  r10,r1,0,0,(31-THREAD_SHIFT)    /* current_thread_info() */
+       li      r11,0
+       stb     r11,TI_SC_NOERR(r10)
        lwz     r11,TI_FLAGS(r10)
        andi.   r11,r11,_TIF_SYSCALL_T_OR_A
        bne-    syscall_dotrace
@@ -225,10 +224,10 @@ ret_from_syscall:
        mr      r6,r3
        li      r11,-_LAST_ERRNO
        cmplw   0,r3,r11
-       rlwinm  r12,r1,0,0,18   /* current_thread_info() */
+       rlwinm  r12,r1,0,0,(31-THREAD_SHIFT)    /* current_thread_info() */
        blt+    30f
-       lwz     r11,TI_LOCAL_FLAGS(r12)
-       andi.   r11,r11,_TIFL_FORCE_NOERROR
+       lbz     r11,TI_SC_NOERR(r12)
+       cmpwi   r11,0
        bne     30f
        neg     r3,r3
        lwz     r10,_CCR(r1)    /* Set SO bit in CR */
@@ -315,7 +314,7 @@ syscall_exit_work:
        LOAD_MSR_KERNEL(r10,MSR_KERNEL) /* doesn't include MSR_EE */
        SYNC
        MTMSRD(r10)             /* disable interrupts again */
-       rlwinm  r12,r1,0,0,18   /* current_thread_info() */
+       rlwinm  r12,r1,0,0,(31-THREAD_SHIFT)    /* current_thread_info() */
        lwz     r9,TI_FLAGS(r12)
 5:
        andi.   r0,r9,_TIF_NEED_RESCHED
@@ -630,7 +629,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_601)
        .globl  sigreturn_exit
 sigreturn_exit:
        subi    r1,r3,STACK_FRAME_OVERHEAD
-       rlwinm  r12,r1,0,0,18   /* current_thread_info() */
+       rlwinm  r12,r1,0,0,(31-THREAD_SHIFT)    /* current_thread_info() */
        lwz     r9,TI_FLAGS(r12)
        andi.   r0,r9,_TIF_SYSCALL_T_OR_A
        beq+    ret_from_except_full
@@ -657,7 +656,7 @@ ret_from_except:
 
 user_exc_return:               /* r10 contains MSR_KERNEL here */
        /* Check current_thread_info()->flags */
-       rlwinm  r9,r1,0,0,18
+       rlwinm  r9,r1,0,0,(31-THREAD_SHIFT)
        lwz     r9,TI_FLAGS(r9)
        andi.   r0,r9,(_TIF_SIGPENDING|_TIF_NEED_RESCHED)
        bne     do_work
@@ -677,7 +676,7 @@ restore_user:
 /* N.B. the only way to get here is from the beq following ret_from_except. */
 resume_kernel:
        /* check current_thread_info->preempt_count */
-       rlwinm  r9,r1,0,0,18
+       rlwinm  r9,r1,0,0,(31-THREAD_SHIFT)
        lwz     r0,TI_PREEMPT(r9)
        cmpwi   0,r0,0          /* if non-zero, just restore regs and return */
        bne     restore
@@ -687,7 +686,7 @@ resume_kernel:
        andi.   r0,r3,MSR_EE    /* interrupts off? */
        beq     restore         /* don't schedule if so */
 1:     bl      preempt_schedule_irq
-       rlwinm  r9,r1,0,0,18
+       rlwinm  r9,r1,0,0,(31-THREAD_SHIFT)
        lwz     r3,TI_FLAGS(r9)
        andi.   r0,r3,_TIF_NEED_RESCHED
        bne-    1b
@@ -889,7 +888,7 @@ recheck:
        LOAD_MSR_KERNEL(r10,MSR_KERNEL)
        SYNC
        MTMSRD(r10)             /* disable interrupts */
-       rlwinm  r9,r1,0,0,18
+       rlwinm  r9,r1,0,0,(31-THREAD_SHIFT)
        lwz     r9,TI_FLAGS(r9)
        andi.   r0,r9,_TIF_NEED_RESCHED
        bne-    do_resched

diff --git a/arch/powerpc/kernel/head_64.S b/arch/powerpc/kernel/head_64.S
index a4ceb9ae20fc01bfd67bcc0790cf695b6b92f090..72b0d26e41d4f280123235d4758907b48a58b132 100644 (file)
--- a/arch/powerpc/kernel/head_64.S
+++ b/arch/powerpc/kernel/head_64.S
@@ -36,6 +36,7 @@
 #include <asm/setup.h>
 #include <asm/hvcall.h>
 #include <asm/iSeries/LparMap.h>
+#include <asm/thread_info.h>
 
 #ifdef CONFIG_PPC_ISERIES
 #define DO_SOFT_DISABLE

diff --git a/arch/powerpc/kernel/misc_64.S b/arch/powerpc/kernel/misc_64.S
index 8fe295693c09e85851b9c9d37c1f221aa1a1fa5f..4775bed42cac84964c9d3784ea0342adcd851d74 100644 (file)
--- a/arch/powerpc/kernel/misc_64.S
+++ b/arch/powerpc/kernel/misc_64.S
@@ -26,6 +26,7 @@
 #include <asm/ppc_asm.h>
 #include <asm/asm-offsets.h>
 #include <asm/cputable.h>
+#include <asm/thread_info.h>
 
        .text
 

diff --git a/arch/ppc/kernel/asm-offsets.c b/arch/ppc/kernel/asm-offsets.c
index 7972db1f65707bcfcb81c683ee70ff1502cfdb3a..968261d6957223a88b3812a414ac0574bb365667 100644 (file)
--- a/arch/ppc/kernel/asm-offsets.c
+++ b/arch/ppc/kernel/asm-offsets.c
@@ -130,10 +130,10 @@ main(void)
        DEFINE(CPU_SPEC_FEATURES, offsetof(struct cpu_spec, cpu_features));
        DEFINE(CPU_SPEC_SETUP, offsetof(struct cpu_spec, cpu_setup));
 
+       DEFINE(TI_SC_NOERR, offsetof(struct thread_info, syscall_noerror));
        DEFINE(TI_TASK, offsetof(struct thread_info, task));
        DEFINE(TI_EXECDOMAIN, offsetof(struct thread_info, exec_domain));
        DEFINE(TI_FLAGS, offsetof(struct thread_info, flags));
-       DEFINE(TI_LOCAL_FLAGS, offsetof(struct thread_info, local_flags));
        DEFINE(TI_CPU, offsetof(struct thread_info, cpu));
        DEFINE(TI_PREEMPT, offsetof(struct thread_info, preempt_count));
 

diff --git a/arch/ppc/kernel/entry.S b/arch/ppc/kernel/entry.S
index 68fc612217764303b891b83392e304ce1743e6db..f044edbb454fe68abf869909a9a180829997e1aa 100644 (file)
--- a/arch/ppc/kernel/entry.S
+++ b/arch/ppc/kernel/entry.S
@@ -200,9 +200,8 @@ _GLOBAL(DoSyscall)
        bl      do_show_syscall
 #endif /* SHOW_SYSCALLS */
        rlwinm  r10,r1,0,0,18   /* current_thread_info() */
-       lwz     r11,TI_LOCAL_FLAGS(r10)
-       rlwinm  r11,r11,0,~_TIFL_FORCE_NOERROR
-       stw     r11,TI_LOCAL_FLAGS(r10)
+       li      r11,0
+       stb     r11,TI_SC_NOERR(r10)
        lwz     r11,TI_FLAGS(r10)
        andi.   r11,r11,_TIF_SYSCALL_T_OR_A
        bne-    syscall_dotrace
@@ -227,8 +226,8 @@ ret_from_syscall:
        cmplw   0,r3,r11
        rlwinm  r12,r1,0,0,18   /* current_thread_info() */
        blt+    30f
-       lwz     r11,TI_LOCAL_FLAGS(r12)
-       andi.   r11,r11,_TIFL_FORCE_NOERROR
+       lbz     r11,TI_SC_NOERR(r12)
+       cmpwi   r11,0
        bne     30f
        neg     r3,r3
        lwz     r10,_CCR(r1)    /* Set SO bit in CR */

diff --git a/arch/ppc64/kernel/asm-offsets.c b/arch/ppc64/kernel/asm-offsets.c
index 1378fbbe1e57e9ff747afec1b6e39f73ce031e8e..5e6046cb414e0da876d9359333ff5f507134340f 100644 (file)
--- a/arch/ppc64/kernel/asm-offsets.c
+++ b/arch/ppc64/kernel/asm-offsets.c
@@ -46,8 +46,6 @@
 int main(void)
 {
        /* thread struct on stack */
-       DEFINE(THREAD_SHIFT, THREAD_SHIFT);
-       DEFINE(THREAD_SIZE, THREAD_SIZE);
        DEFINE(TI_FLAGS, offsetof(struct thread_info, flags));
        DEFINE(TI_PREEMPT, offsetof(struct thread_info, preempt_count));
        DEFINE(TI_SC_NOERR, offsetof(struct thread_info, syscall_noerror));

diff --git a/arch/ppc64/kernel/head.S b/arch/ppc64/kernel/head.S
index d5e6be2007648890fb6b6fdbb09742dba6ac016b..15c5f0c48043ec4e801692786faa229952916d68 100644 (file)
--- a/arch/ppc64/kernel/head.S
+++ b/arch/ppc64/kernel/head.S
@@ -36,6 +36,7 @@
 #include <asm/setup.h>
 #include <asm/hvcall.h>
 #include <asm/iSeries/LparMap.h>
+#include <asm/thread_info.h>
 
 #ifdef CONFIG_PPC_ISERIES
 #define DO_SOFT_DISABLE

diff --git a/arch/ppc64/kernel/misc.S b/arch/ppc64/kernel/misc.S
index ad73aad8dbb679a260f8deec8a6427d88edc6031..a33448c2bd916de78f251ed7be9ea1d9973c3b5f 100644 (file)
--- a/arch/ppc64/kernel/misc.S
+++ b/arch/ppc64/kernel/misc.S
@@ -28,6 +28,7 @@
 #include <asm/ppc_asm.h>
 #include <asm/asm-offsets.h>
 #include <asm/cputable.h>
+#include <asm/thread_info.h>
 
        .text
 

diff --git a/include/asm-ppc64/thread_info.h b/include/asm-powerpc/thread_info.h
similarity index 84%
rename from include/asm-ppc64/thread_info.h
rename to include/asm-powerpc/thread_info.h
index 71244d8a427d3b175716400597b06d7cdaf677d6..0b4c24551c21fc8df7bdeccce6bacc9de99642e2 100644 (file)
--- a/include/asm-ppc64/thread_info.h
+++ b/include/asm-powerpc/thread_info.h
@@ -1,15 +1,25 @@
-/* thread_info.h: PPC low-level thread information
+/* thread_info.h: PowerPC low-level thread information
  * adapted from the i386 version by Paul Mackerras
  *
  * Copyright (C) 2002  David Howells (dhowells@redhat.com)
  * - Incorporating suggestions made by Linus Torvalds and Dave Miller
  */
 
-#ifndef _ASM_THREAD_INFO_H
-#define _ASM_THREAD_INFO_H
+#ifndef _ASM_POWERPC_THREAD_INFO_H
+#define _ASM_POWERPC_THREAD_INFO_H
 
 #ifdef __KERNEL__
 
+/* We have 8k stacks on ppc32 and 16k on ppc64 */
+
+#ifdef CONFIG_PPC64
+#define THREAD_SHIFT           14
+#else
+#define THREAD_SHIFT           13
+#endif
+
+#define THREAD_SIZE            (1 << THREAD_SHIFT)
+
 #ifndef __ASSEMBLY__
 #include <linux/config.h>
 #include <linux/cache.h>
@@ -24,7 +34,8 @@ struct thread_info {
        struct task_struct *task;               /* main task structure */
        struct exec_domain *exec_domain;        /* execution domain */
        int             cpu;                    /* cpu we're on */
-       int             preempt_count;          /* 0 => preemptable, <0 => BUG */
+       int             preempt_count;          /* 0 => preemptable,
+                                                  <0 => BUG */
        struct restart_block restart_block;
        /* set by force_successful_syscall_return */
        unsigned char   syscall_noerror;
@@ -54,9 +65,6 @@ struct thread_info {
 
 /* thread information allocation */
 
-#define THREAD_SHIFT           14
-#define THREAD_ORDER           (THREAD_SHIFT - PAGE_SHIFT)
-#define THREAD_SIZE            (1 << THREAD_SHIFT)
 #ifdef CONFIG_DEBUG_STACK_USAGE
 #define alloc_thread_info(tsk)                                 \
        ({                                                      \
@@ -68,7 +76,7 @@ struct thread_info {
                ret;                                            \
        })
 #else
-#define alloc_thread_info(tsk) kmalloc(THREAD_SIZE, GFP_KERNEL)
+#define alloc_thread_info(tsk) kmalloc(THREAD_SIZE, GFP_KERNEL)
 #endif
 #define free_thread_info(ti)   kfree(ti)
 #define get_thread_info(ti)    get_task_struct((ti)->task)
@@ -77,9 +85,11 @@ struct thread_info {
 /* how to get the thread information struct from C */
 static inline struct thread_info *current_thread_info(void)
 {
-       struct thread_info *ti;
-       __asm__("clrrdi %0,1,%1" : "=r"(ti) : "i" (THREAD_SHIFT));
-       return ti;
+       register unsigned long sp asm("r1");
+
+       /* gcc4, at least, is smart enough to turn this into a single
+        * rlwinm for ppc32 and clrrdi for ppc64 */
+       return (struct thread_info *)(sp & ~(THREAD_SIZE-1));
 }
 
 #endif /* __ASSEMBLY__ */
@@ -122,4 +132,4 @@ static inline struct thread_info *current_thread_info(void)
 
 #endif /* __KERNEL__ */
 
-#endif /* _ASM_THREAD_INFO_H */
+#endif /* _ASM_POWERPC_THREAD_INFO_H */

diff --git a/include/asm-ppc/ptrace.h b/include/asm-ppc/ptrace.h
index 7043c164b5375d98a9ae8794b1b77db89653b3ab..c34fb4e37a9739419bb35b5a7c2dbf41c3f2cac4 100644 (file)
--- a/include/asm-ppc/ptrace.h
+++ b/include/asm-ppc/ptrace.h
@@ -57,7 +57,7 @@ extern unsigned long profile_pc(struct pt_regs *regs);
 
 #define force_successful_syscall_return()   \
        do { \
-               current_thread_info()->local_flags |= _TIFL_FORCE_NOERROR; \
+               current_thread_info()->syscall_noerror = 1; \
        } while(0)
 
 /*

diff --git a/include/asm-ppc/thread_info.h b/include/asm-ppc/thread_info.h
deleted file mode 100644 (file)
index 27903db..0000000
--- a/include/asm-ppc/thread_info.h
+++ /dev/null
@@ -1,107 +0,0 @@
-/* thread_info.h: PPC low-level thread information
- * adapted from the i386 version by Paul Mackerras
- *
- * Copyright (C) 2002  David Howells (dhowells@redhat.com)
- * - Incorporating suggestions made by Linus Torvalds and Dave Miller
- */
-
-#ifndef _ASM_THREAD_INFO_H
-#define _ASM_THREAD_INFO_H
-
-#ifdef __KERNEL__
-#ifndef __ASSEMBLY__
-/*
- * low level task data.
- * If you change this, change the TI_* offsets below to match.
- */
-struct thread_info {
-       struct task_struct      *task;          /* main task structure */
-       struct exec_domain      *exec_domain;   /* execution domain */
-       unsigned long           flags;          /* low level flags */
-       unsigned long           local_flags;    /* non-racy flags */
-       int                     cpu;            /* cpu we're on */
-       int                     preempt_count;  /* 0 => preemptable,
-                                                  <0 => BUG */
-       struct restart_block    restart_block;
-};
-
-#define INIT_THREAD_INFO(tsk)                  \
-{                                              \
-       .task =         &tsk,                   \
-       .exec_domain =  &default_exec_domain,   \
-       .flags =        0,                      \
-       .local_flags =  0,                      \
-       .cpu =          0,                      \
-       .preempt_count = 1,                     \
-       .restart_block = {                      \
-               .fn = do_no_restart_syscall,    \
-       },                                      \
-}
-
-#define init_thread_info       (init_thread_union.thread_info)
-#define init_stack             (init_thread_union.stack)
-
-/*
- * macros/functions for gaining access to the thread information structure
- */
-
-/* how to get the thread information struct from C */
-static inline struct thread_info *current_thread_info(void)
-{
-       struct thread_info *ti;
-       __asm__("rlwinm %0,1,0,0,18" : "=r"(ti));
-       return ti;
-}
-
-/* thread information allocation */
-#define alloc_thread_info(tsk) ((struct thread_info *) \
-                               __get_free_pages(GFP_KERNEL, 1))
-#define free_thread_info(ti)   free_pages((unsigned long) (ti), 1)
-#define get_thread_info(ti)    get_task_struct((ti)->task)
-#define put_thread_info(ti)    put_task_struct((ti)->task)
-#endif /* __ASSEMBLY__ */
-
-/*
- * Size of kernel stack for each process.
- */
-#define THREAD_SIZE            8192    /* 2 pages */
-
-#define PREEMPT_ACTIVE         0x10000000
-
-/*
- * thread information flag bit numbers
- */
-#define TIF_SYSCALL_TRACE      0       /* syscall trace active */
-#define TIF_NOTIFY_RESUME      1       /* resumption notification requested */
-#define TIF_SIGPENDING         2       /* signal pending */
-#define TIF_NEED_RESCHED       3       /* rescheduling necessary */
-#define TIF_POLLING_NRFLAG     4       /* true if poll_idle() is polling
-                                          TIF_NEED_RESCHED */
-#define TIF_MEMDIE             5
-#define TIF_SYSCALL_AUDIT       6       /* syscall auditing active */
-#define TIF_SECCOMP             7      /* secure computing */
-
-/* as above, but as bit values */
-#define _TIF_SYSCALL_TRACE     (1<<TIF_SYSCALL_TRACE)
-#define _TIF_NOTIFY_RESUME     (1<<TIF_NOTIFY_RESUME)
-#define _TIF_SIGPENDING                (1<<TIF_SIGPENDING)
-#define _TIF_NEED_RESCHED      (1<<TIF_NEED_RESCHED)
-#define _TIF_POLLING_NRFLAG    (1<<TIF_POLLING_NRFLAG)
-#define _TIF_SYSCALL_AUDIT      (1<<TIF_SYSCALL_AUDIT)
-#define _TIF_SECCOMP            (1<<TIF_SECCOMP)
-
-#define _TIF_SYSCALL_T_OR_A     (_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT|_TIF_SECCOMP)
-
-/*
- * Non racy (local) flags bit numbers
- */
-#define TIFL_FORCE_NOERROR     0       /* don't return error from current
-                                          syscall even if result < 0 */
-
-/* as above, but as bit values */
-#define _TIFL_FORCE_NOERROR    (1<<TIFL_FORCE_NOERROR)
-
-
-#endif /* __KERNEL__ */
-
-#endif /* _ASM_THREAD_INFO_H */