[POWERPC] Define and use TLF_RESTORE_SIGMASK

Replace TIF_RESTORE_SIGMASK with TLF_RESTORE_SIGMASK and define
our own set_restore_sigmask() function.  This saves the costly
SMP-safe set_bit operation, which we do not need for the sigmask
flag since TIF_SIGPENDING always has to be set too.

Signed-off-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>

diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S
index 0c8614d9875ca8b5966c148c7ad447bbcf3a987d..3a05e9f93d426be90ec100e3aeb2c5c47283f74f 100644 (file)
--- a/arch/powerpc/kernel/entry_32.S
+++ b/arch/powerpc/kernel/entry_32.S
@@ -668,7 +668,7 @@ user_exc_return:            /* r10 contains MSR_KERNEL here */
        /* Check current_thread_info()->flags */
        rlwinm  r9,r1,0,0,(31-THREAD_SHIFT)
        lwz     r9,TI_FLAGS(r9)
-       andi.   r0,r9,(_TIF_SIGPENDING|_TIF_RESTORE_SIGMASK|_TIF_NEED_RESCHED)
+       andi.   r0,r9,_TIF_USER_WORK_MASK
        bne     do_work
 
 restore_user:
@@ -925,7 +925,7 @@ recheck:
        lwz     r9,TI_FLAGS(r9)
        andi.   r0,r9,_TIF_NEED_RESCHED
        bne-    do_resched
-       andi.   r0,r9,_TIF_SIGPENDING|_TIF_RESTORE_SIGMASK
+       andi.   r0,r9,_TIF_USER_WORK_MASK
        beq     restore_user
 do_user_signal:                        /* r10 contains MSR_KERNEL here */
        ori     r10,r10,MSR_EE

diff --git a/arch/powerpc/kernel/signal.c b/arch/powerpc/kernel/signal.c
index a65a44fbe52375c5b1b5ca7a8deb33305ab11536..ad55488939c376f7073b0770ca79ad1f5954ca1e 100644 (file)
--- a/arch/powerpc/kernel/signal.c
+++ b/arch/powerpc/kernel/signal.c
@@ -120,7 +120,7 @@ int do_signal(sigset_t *oldset, struct pt_regs *regs)
        int ret;
        int is32 = is_32bit_task();
 
-       if (test_thread_flag(TIF_RESTORE_SIGMASK))
+       if (current_thread_info()->local_flags & _TLF_RESTORE_SIGMASK)
                oldset = &current->saved_sigmask;
        else if (!oldset)
                oldset = &current->blocked;
@@ -131,9 +131,10 @@ int do_signal(sigset_t *oldset, struct pt_regs *regs)
        check_syscall_restart(regs, &ka, signr > 0);
 
        if (signr <= 0) {
+               struct thread_info *ti = current_thread_info();
                /* No signal to deliver -- put the saved sigmask back */
-               if (test_thread_flag(TIF_RESTORE_SIGMASK)) {
-                       clear_thread_flag(TIF_RESTORE_SIGMASK);
+               if (ti->local_flags & _TLF_RESTORE_SIGMASK) {
+                       ti->local_flags &= ~_TLF_RESTORE_SIGMASK;
                        sigprocmask(SIG_SETMASK, &current->saved_sigmask, NULL);
                }
                return 0;               /* no signals delivered */
@@ -169,10 +170,9 @@ int do_signal(sigset_t *oldset, struct pt_regs *regs)
 
                /*
                 * A signal was successfully delivered; the saved sigmask is in
-                * its frame, and we can clear the TIF_RESTORE_SIGMASK flag.
+                * its frame, and we can clear the TLF_RESTORE_SIGMASK flag.
                 */
-               if (test_thread_flag(TIF_RESTORE_SIGMASK))
-                       clear_thread_flag(TIF_RESTORE_SIGMASK);
+               current_thread_info()->local_flags &= ~_TLF_RESTORE_SIGMASK;
        }
 
        return ret;

diff --git a/arch/powerpc/kernel/signal_32.c b/arch/powerpc/kernel/signal_32.c
index ad6943468ee9f25aee853a3ded8f99271f1c3d72..4ae16d179803ef6071cd07909b86dd91ad032b62 100644 (file)
--- a/arch/powerpc/kernel/signal_32.c
+++ b/arch/powerpc/kernel/signal_32.c
@@ -243,7 +243,7 @@ long sys_sigsuspend(old_sigset_t mask)
 
        current->state = TASK_INTERRUPTIBLE;
        schedule();
-       set_thread_flag(TIF_RESTORE_SIGMASK);
+       set_restore_sigmask();
        return -ERESTARTNOHAND;
 }
 

diff --git a/arch/ppc/kernel/entry.S b/arch/ppc/kernel/entry.S
index 5f3a5d068a5c6af9475babc8828d0e87f4290245..fcd830a292e24186ede36195ba4558d0312e2aa3 100644 (file)
--- a/arch/ppc/kernel/entry.S
+++ b/arch/ppc/kernel/entry.S
@@ -647,7 +647,7 @@ user_exc_return:            /* r10 contains MSR_KERNEL here */
        /* Check current_thread_info()->flags */
        rlwinm  r9,r1,0,0,18
        lwz     r9,TI_FLAGS(r9)
-       andi.   r0,r9,(_TIF_SIGPENDING|_TIF_RESTORE_SIGMASK|_TIF_NEED_RESCHED)
+       andi.   r0,r9,_TIF_USER_WORK_MASK
        bne     do_work
 
 restore_user:
@@ -898,7 +898,7 @@ recheck:
        lwz     r9,TI_FLAGS(r9)
        andi.   r0,r9,_TIF_NEED_RESCHED
        bne-    do_resched
-       andi.   r0,r9,_TIF_SIGPENDING
+       andi.   r0,r9,_TIF_USER_WORK_MASK
        beq     restore_user
 do_user_signal:                        /* r10 contains MSR_KERNEL here */
        ori     r10,r10,MSR_EE

diff --git a/include/asm-powerpc/thread_info.h b/include/asm-powerpc/thread_info.h
index d030f5ce39adafdac57aa0fd93d88bc8f985b2ea..e079e81051fda1371c5ef7958d4cdd18a30e224a 100644 (file)
--- a/include/asm-powerpc/thread_info.h
+++ b/include/asm-powerpc/thread_info.h
@@ -116,7 +116,6 @@ static inline struct thread_info *current_thread_info(void)
 #define TIF_SECCOMP            10      /* secure computing */
 #define TIF_RESTOREALL         11      /* Restore all regs (implies NOERROR) */
 #define TIF_NOERROR            12      /* Force successful syscall return */
-#define TIF_RESTORE_SIGMASK    13      /* Restore signal mask in do_signal */
 #define TIF_FREEZE             14      /* Freezing for suspend */
 #define TIF_RUNLATCH           15      /* Is the runlatch enabled? */
 #define TIF_ABI_PENDING                16      /* 32/64 bit switch needed */
@@ -134,21 +133,31 @@ static inline struct thread_info *current_thread_info(void)
 #define _TIF_SECCOMP           (1<<TIF_SECCOMP)
 #define _TIF_RESTOREALL                (1<<TIF_RESTOREALL)
 #define _TIF_NOERROR           (1<<TIF_NOERROR)
-#define _TIF_RESTORE_SIGMASK   (1<<TIF_RESTORE_SIGMASK)
 #define _TIF_FREEZE            (1<<TIF_FREEZE)
 #define _TIF_RUNLATCH          (1<<TIF_RUNLATCH)
 #define _TIF_ABI_PENDING       (1<<TIF_ABI_PENDING)
 #define _TIF_SYSCALL_T_OR_A    (_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT|_TIF_SECCOMP)
 
-#define _TIF_USER_WORK_MASK    ( _TIF_SIGPENDING | \
-                                _TIF_NEED_RESCHED | _TIF_RESTORE_SIGMASK)
+#define _TIF_USER_WORK_MASK    (_TIF_SIGPENDING | _TIF_NEED_RESCHED)
 #define _TIF_PERSYSCALL_MASK   (_TIF_RESTOREALL|_TIF_NOERROR)
 
 /* Bits in local_flags */
 /* Don't move TLF_NAPPING without adjusting the code in entry_32.S */
 #define TLF_NAPPING            0       /* idle thread enabled NAP mode */
+#define TLF_RESTORE_SIGMASK    1       /* Restore signal mask in do_signal */
 
 #define _TLF_NAPPING           (1 << TLF_NAPPING)
+#define _TLF_RESTORE_SIGMASK   (1 << TLF_RESTORE_SIGMASK)
+
+#ifndef __ASSEMBLY__
+#define HAVE_SET_RESTORE_SIGMASK       1
+static inline void set_restore_sigmask(void)
+{
+       struct thread_info *ti = current_thread_info();
+       ti->local_flags |= _TLF_RESTORE_SIGMASK;
+       set_bit(TIF_SIGPENDING, &ti->flags);
+}
+#endif /* !__ASSEMBLY__ */
 
 #endif /* __KERNEL__ */