From 5a8da0ea82db6fa9737041381079fd16f25dcce2 Mon Sep 17 00:00:00 2001 From: Roland McGrath Date: Wed, 30 Apr 2008 00:53:10 -0700 Subject: [PATCH] signals: x86 TS_RESTORE_SIGMASK Replace TIF_RESTORE_SIGMASK with TS_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 Cc: Oleg Nesterov Cc: Ingo Molnar Cc: Thomas Gleixner Cc: Martin Schwidefsky Cc: Heiko Carstens Cc: "Luck, Tony" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/x86/ia32/ia32_signal.c | 2 +- arch/x86/kernel/signal_32.c | 17 ++++++++--------- arch/x86/kernel/signal_64.c | 16 +++++++++------- include/asm-x86/thread_info_32.h | 13 +++++++++++-- include/asm-x86/thread_info_64.h | 13 +++++++++++-- 5 files changed, 40 insertions(+), 21 deletions(-) diff --git a/arch/x86/ia32/ia32_signal.c b/arch/x86/ia32/ia32_signal.c index bbed3a26ce55..cb3856a18c85 100644 --- a/arch/x86/ia32/ia32_signal.c +++ b/arch/x86/ia32/ia32_signal.c @@ -128,7 +128,7 @@ asmlinkage long sys32_sigsuspend(int history0, int history1, old_sigset_t mask) current->state = TASK_INTERRUPTIBLE; schedule(); - set_thread_flag(TIF_RESTORE_SIGMASK); + set_restore_sigmask(); return -ERESTARTNOHAND; } diff --git a/arch/x86/kernel/signal_32.c b/arch/x86/kernel/signal_32.c index 8e05e7f7bd40..d92373630963 100644 --- a/arch/x86/kernel/signal_32.c +++ b/arch/x86/kernel/signal_32.c @@ -57,7 +57,7 @@ sys_sigsuspend(int history0, int history1, old_sigset_t mask) current->state = TASK_INTERRUPTIBLE; schedule(); - set_thread_flag(TIF_RESTORE_SIGMASK); + set_restore_sigmask(); return -ERESTARTNOHAND; } @@ -593,7 +593,7 @@ static void do_signal(struct pt_regs *regs) if (!user_mode(regs)) return; - if (test_thread_flag(TIF_RESTORE_SIGMASK)) + if (current_thread_info()->status & TS_RESTORE_SIGMASK) oldset = ¤t->saved_sigmask; else oldset = ¤t->blocked; @@ -612,13 +612,12 @@ static void do_signal(struct pt_regs *regs) /* Whee! Actually deliver the signal. */ if (handle_signal(signr, &info, &ka, oldset, regs) == 0) { /* - * a signal was successfully delivered; the saved + * A signal was successfully delivered; the saved * sigmask will have been stored in the signal frame, * and will be restored by sigreturn, so we can simply - * clear the TIF_RESTORE_SIGMASK flag + * clear the TS_RESTORE_SIGMASK flag. */ - if (test_thread_flag(TIF_RESTORE_SIGMASK)) - clear_thread_flag(TIF_RESTORE_SIGMASK); + current_thread_info()->status &= ~TS_RESTORE_SIGMASK; } return; } @@ -645,8 +644,8 @@ static void do_signal(struct pt_regs *regs) * If there's no signal to deliver, we just put the saved sigmask * back. */ - if (test_thread_flag(TIF_RESTORE_SIGMASK)) { - clear_thread_flag(TIF_RESTORE_SIGMASK); + if (current_thread_info()->status & TS_RESTORE_SIGMASK) { + current_thread_info()->status &= ~TS_RESTORE_SIGMASK; sigprocmask(SIG_SETMASK, ¤t->saved_sigmask, NULL); } } @@ -665,7 +664,7 @@ do_notify_resume(struct pt_regs *regs, void *unused, __u32 thread_info_flags) } /* deal with pending signal delivery */ - if (thread_info_flags & (_TIF_SIGPENDING | _TIF_RESTORE_SIGMASK)) + if (thread_info_flags & _TIF_SIGPENDING) do_signal(regs); if (thread_info_flags & _TIF_HRTICK_RESCHED) diff --git a/arch/x86/kernel/signal_64.c b/arch/x86/kernel/signal_64.c index ccb2a4560c2d..e53b267662e7 100644 --- a/arch/x86/kernel/signal_64.c +++ b/arch/x86/kernel/signal_64.c @@ -427,7 +427,7 @@ static void do_signal(struct pt_regs *regs) if (!user_mode(regs)) return; - if (test_thread_flag(TIF_RESTORE_SIGMASK)) + if (current_thread_info()->status & TS_RESTORE_SIGMASK) oldset = ¤t->saved_sigmask; else oldset = ¤t->blocked; @@ -444,11 +444,13 @@ static void do_signal(struct pt_regs *regs) /* Whee! Actually deliver the signal. */ if (handle_signal(signr, &info, &ka, oldset, regs) == 0) { - /* a signal was successfully delivered; the saved + /* + * A signal was successfully delivered; the saved * sigmask will have been stored in the signal frame, * and will be restored by sigreturn, so we can simply - * clear the TIF_RESTORE_SIGMASK flag */ - clear_thread_flag(TIF_RESTORE_SIGMASK); + * clear the TS_RESTORE_SIGMASK flag. + */ + current_thread_info()->status &= ~TS_RESTORE_SIGMASK; } return; } @@ -476,8 +478,8 @@ static void do_signal(struct pt_regs *regs) * If there's no signal to deliver, we just put the saved sigmask * back. */ - if (test_thread_flag(TIF_RESTORE_SIGMASK)) { - clear_thread_flag(TIF_RESTORE_SIGMASK); + if (current_thread_info()->status & TS_RESTORE_SIGMASK) { + current_thread_info()->status &= ~TS_RESTORE_SIGMASK; sigprocmask(SIG_SETMASK, ¤t->saved_sigmask, NULL); } } @@ -498,7 +500,7 @@ void do_notify_resume(struct pt_regs *regs, void *unused, #endif /* CONFIG_X86_MCE */ /* deal with pending signal delivery */ - if (thread_info_flags & (_TIF_SIGPENDING | _TIF_RESTORE_SIGMASK)) + if (thread_info_flags & _TIF_SIGPENDING) do_signal(regs); if (thread_info_flags & _TIF_HRTICK_RESCHED) diff --git a/include/asm-x86/thread_info_32.h b/include/asm-x86/thread_info_32.h index 531859962096..b6338829d1a8 100644 --- a/include/asm-x86/thread_info_32.h +++ b/include/asm-x86/thread_info_32.h @@ -131,7 +131,6 @@ static inline struct thread_info *current_thread_info(void) #define TIF_SYSCALL_EMU 5 /* syscall emulation active */ #define TIF_SYSCALL_AUDIT 6 /* syscall auditing active */ #define TIF_SECCOMP 7 /* secure computing */ -#define TIF_RESTORE_SIGMASK 8 /* restore signal mask in do_signal() */ #define TIF_HRTICK_RESCHED 9 /* reprogram hrtick timer */ #define TIF_MEMDIE 16 #define TIF_DEBUG 17 /* uses debug registers */ @@ -151,7 +150,6 @@ static inline struct thread_info *current_thread_info(void) #define _TIF_SYSCALL_EMU (1 << TIF_SYSCALL_EMU) #define _TIF_SYSCALL_AUDIT (1 << TIF_SYSCALL_AUDIT) #define _TIF_SECCOMP (1 << TIF_SECCOMP) -#define _TIF_RESTORE_SIGMASK (1 << TIF_RESTORE_SIGMASK) #define _TIF_HRTICK_RESCHED (1 << TIF_HRTICK_RESCHED) #define _TIF_DEBUG (1 << TIF_DEBUG) #define _TIF_IO_BITMAP (1 << TIF_IO_BITMAP) @@ -188,9 +186,20 @@ static inline struct thread_info *current_thread_info(void) this quantum (SMP) */ #define TS_POLLING 0x0002 /* True if in idle loop and not sleeping */ +#define TS_RESTORE_SIGMASK 0x0004 /* restore signal mask in do_signal() */ #define tsk_is_polling(t) (task_thread_info(t)->status & TS_POLLING) +#ifndef __ASSEMBLY__ +#define HAVE_SET_RESTORE_SIGMASK 1 +static inline void set_restore_sigmask(void) +{ + struct thread_info *ti = current_thread_info(); + ti->status |= TS_RESTORE_SIGMASK; + set_bit(TIF_SIGPENDING, &ti->flags); +} +#endif /* !__ASSEMBLY__ */ + #endif /* __KERNEL__ */ #endif /* _ASM_THREAD_INFO_H */ diff --git a/include/asm-x86/thread_info_64.h b/include/asm-x86/thread_info_64.h index ed664e874dec..cb69f70abba1 100644 --- a/include/asm-x86/thread_info_64.h +++ b/include/asm-x86/thread_info_64.h @@ -109,7 +109,6 @@ static inline struct thread_info *stack_thread_info(void) #define TIF_IRET 5 /* force IRET */ #define TIF_SYSCALL_AUDIT 7 /* syscall auditing active */ #define TIF_SECCOMP 8 /* secure computing */ -#define TIF_RESTORE_SIGMASK 9 /* restore signal mask in do_signal */ #define TIF_MCE_NOTIFY 10 /* notify userspace of an MCE */ #define TIF_HRTICK_RESCHED 11 /* reprogram hrtick timer */ /* 16 free */ @@ -133,7 +132,6 @@ static inline struct thread_info *stack_thread_info(void) #define _TIF_IRET (1 << TIF_IRET) #define _TIF_SYSCALL_AUDIT (1 << TIF_SYSCALL_AUDIT) #define _TIF_SECCOMP (1 << TIF_SECCOMP) -#define _TIF_RESTORE_SIGMASK (1 << TIF_RESTORE_SIGMASK) #define _TIF_MCE_NOTIFY (1 << TIF_MCE_NOTIFY) #define _TIF_HRTICK_RESCHED (1 << TIF_HRTICK_RESCHED) #define _TIF_IA32 (1 << TIF_IA32) @@ -178,9 +176,20 @@ static inline struct thread_info *stack_thread_info(void) #define TS_COMPAT 0x0002 /* 32bit syscall active */ #define TS_POLLING 0x0004 /* true if in idle loop and not sleeping */ +#define TS_RESTORE_SIGMASK 0x0008 /* restore signal mask in do_signal() */ #define tsk_is_polling(t) (task_thread_info(t)->status & TS_POLLING) +#ifndef __ASSEMBLY__ +#define HAVE_SET_RESTORE_SIGMASK 1 +static inline void set_restore_sigmask(void) +{ + struct thread_info *ti = current_thread_info(); + ti->status |= TS_RESTORE_SIGMASK; + set_bit(TIF_SIGPENDING, &ti->flags); +} +#endif /* !__ASSEMBLY__ */ + #endif /* __KERNEL__ */ #endif /* _ASM_THREAD_INFO_H */ -- GitLab