diff options
author | Oleg Nesterov <oleg@redhat.com> | 2014-06-07 01:37:00 +0400 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2014-06-07 03:08:12 +0400 |
commit | b4e74264eb0b03f42097fa70a0766312156244a0 (patch) | |
tree | f681b406765648b4fb6dde9b1c672b1276937a79 | |
parent | 580d34e42ad621736a3c53c9c11a2152c18a4068 (diff) | |
download | linux-b4e74264eb0b03f42097fa70a0766312156244a0.tar.xz |
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 <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-rw-r--r-- | include/linux/signal.h | 18 | ||||
-rw-r--r-- | kernel/signal.c | 36 |
2 files changed, 28 insertions, 26 deletions
diff --git a/include/linux/signal.h b/include/linux/signal.h index ac83c593f4b9..c9e65360c49a 100644 --- a/include/linux/signal.h +++ b/include/linux/signal.h @@ -284,8 +284,22 @@ extern int get_signal_to_deliver(siginfo_t *info, struct k_sigaction *return_ka, extern void signal_setup_done(int failed, struct ksignal *ksig, int stepping); extern void signal_delivered(int sig, siginfo_t *info, struct k_sigaction *ka, struct pt_regs *regs, int stepping); extern void exit_signals(struct task_struct *tsk); -extern void allow_signal(int); -extern void disallow_signal(int); +extern void kernel_sigaction(int, __sighandler_t); + +static inline void allow_signal(int sig) +{ + /* + * 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. + */ + kernel_sigaction(sig, (__force __sighandler_t)2); +} + +static inline void disallow_signal(int sig) +{ + kernel_sigaction(sig, SIG_IGN); +} /* * Eventually that'll replace get_signal_to_deliver(); macro for now, 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) { |