From 2acb024d5524eda305523c1d6061fe5ef1949165 Mon Sep 17 00:00:00 2001 From: Pavel Emelyanov Date: Wed, 30 Apr 2008 00:52:35 -0700 Subject: [PATCH] signals: consolidate checking for ignored/legacy signals Two callers for send_signal() - the specific_send_sig_info and the __group_send_sig_info - both check for sig to be ignored or already queued. Move these checks into send_signal() and make it return 1 to indicate that the signal is dropped, but there's no error in this. Besides, merge comments and spell-check them. [oleg@tv-sign.ru: simplifications] Signed-off-by: Pavel Emelyanov Cc: Roland McGrath Signed-off-by: Oleg Nesterov Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- kernel/signal.c | 42 +++++++++++++++++------------------------- 1 file changed, 17 insertions(+), 25 deletions(-) diff --git a/kernel/signal.c b/kernel/signal.c index 772aa011dad..fb8ffd46885 100644 --- a/kernel/signal.c +++ b/kernel/signal.c @@ -667,6 +667,14 @@ static int send_signal(int sig, struct siginfo *info, struct task_struct *t, { struct sigqueue * q = NULL; + /* + * Short-circuit ignored signals and support queuing + * exactly one non-rt signal, so that we can get more + * detailed information about the cause of the signal. + */ + if (sig_ignored(t, sig) || legacy_queue(signals, sig)) + return 0; + /* * Deliver the signal to listening signalfds. This must be called * with the sighand lock held. @@ -723,7 +731,7 @@ static int send_signal(int sig, struct siginfo *info, struct task_struct *t, out_set: sigaddset(&signals->signal, sig); - return 0; + return 1; } int print_fatal_signals; @@ -761,26 +769,18 @@ __setup("print-fatal-signals=", setup_print_fatal_signals); static int specific_send_sig_info(int sig, struct siginfo *info, struct task_struct *t) { - int ret = 0; + int ret; BUG_ON(!irqs_disabled()); assert_spin_locked(&t->sighand->siglock); - /* Short-circuit ignored signals. */ - if (sig_ignored(t, sig)) - goto out; - - /* Support queueing exactly one non-rt signal, so that we - can get more detailed information about the cause of - the signal. */ - if (legacy_queue(&t->pending, sig)) - goto out; - ret = send_signal(sig, info, t, &t->pending); - if (!ret && !sigismember(&t->blocked, sig)) + if (ret <= 0) + return ret; + + if (!sigismember(&t->blocked, sig)) signal_wake_up(t, sig == SIGKILL); -out: - return ret; + return 0; } /* @@ -925,26 +925,18 @@ __group_complete_signal(int sig, struct task_struct *p) int __group_send_sig_info(int sig, struct siginfo *info, struct task_struct *p) { - int ret = 0; + int ret; assert_spin_locked(&p->sighand->siglock); handle_stop_signal(sig, p); - /* Short-circuit ignored signals. */ - if (sig_ignored(p, sig)) - return ret; - - if (legacy_queue(&p->signal->shared_pending, sig)) - /* This is a non-RT signal and we already have one queued. */ - return ret; - /* * Put this signal on the shared-pending queue, or fail with EAGAIN. * We always use the shared queue for process-wide signals, * to avoid several races. */ ret = send_signal(sig, info, p, &p->signal->shared_pending); - if (unlikely(ret)) + if (ret <= 0) return ret; __group_complete_signal(sig, p);