From b4e74264eb0b03f42097fa70a0766312156244a0 Mon Sep 17 00:00:00 2001 From: Oleg Nesterov Date: Fri, 6 Jun 2014 14:37:00 -0700 Subject: signals: introduce kernel_sigaction() Now that allow_signal() is really trivial we can unify it with disallow_signal(). Add the new helper, kernel_sigaction(), and reimplement allow_signal/disallow_signal as a trivial wrappers. This saves one EXPORT_SYMBOL() and the new helper can have more users. Signed-off-by: Oleg Nesterov Cc: Peter Zijlstra Cc: Al Viro Cc: David Woodhouse Cc: Frederic Weisbecker Cc: Geert Uytterhoeven Cc: Ingo Molnar Cc: Mathieu Desnoyers Cc: Richard Weinberger Cc: Steven Rostedt Cc: Tejun Heo Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- kernel/signal.c | 36 ++++++++++++------------------------ 1 file changed, 12 insertions(+), 24 deletions(-) (limited to 'kernel/signal.c') diff --git a/kernel/signal.c b/kernel/signal.c index 3ec405132c79..a4077e90f19f 100644 --- a/kernel/signal.c +++ b/kernel/signal.c @@ -3067,37 +3067,25 @@ COMPAT_SYSCALL_DEFINE4(rt_tgsigqueueinfo, #endif /* - * Let kernel threads use this to say that they allow a certain signal. - * Must not be used if kthread was cloned with CLONE_SIGHAND. + * For kthreads only, must not be used if cloned with CLONE_SIGHAND */ -void allow_signal(int sig) +void kernel_sigaction(int sig, __sighandler_t action) { - /* - * Kernel threads handle their own signals. Let the signal code - * know it'll be handled, so that they don't get converted to - * SIGKILL or just silently dropped. - */ spin_lock_irq(¤t->sighand->siglock); - current->sighand->action[(sig)-1].sa.sa_handler = (void __user *)2; - spin_unlock_irq(¤t->sighand->siglock); -} -EXPORT_SYMBOL(allow_signal); + current->sighand->action[sig - 1].sa.sa_handler = action; + if (action == SIG_IGN) { + sigset_t mask; -void disallow_signal(int sig) -{ - sigset_t mask; + sigemptyset(&mask); + sigaddset(&mask, sig); - sigemptyset(&mask); - sigaddset(&mask, sig); - - spin_lock_irq(¤t->sighand->siglock); - current->sighand->action[(sig)-1].sa.sa_handler = SIG_IGN; - flush_sigqueue_mask(&mask, ¤t->signal->shared_pending); - flush_sigqueue_mask(&mask, ¤t->pending); - recalc_sigpending(); + flush_sigqueue_mask(&mask, ¤t->signal->shared_pending); + flush_sigqueue_mask(&mask, ¤t->pending); + recalc_sigpending(); + } spin_unlock_irq(¤t->sighand->siglock); } -EXPORT_SYMBOL(disallow_signal); +EXPORT_SYMBOL(kernel_sigaction); int do_sigaction(int sig, struct k_sigaction *act, struct k_sigaction *oact) { -- cgit v1.2.3