Commit 2acb024d authored by Pavel Emelyanov's avatar Pavel Emelyanov Committed by Linus Torvalds
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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: default avatarPavel Emelyanov <xemul@openvz.org>
Cc: Roland McGrath <roland@redhat.com>
Signed-off-by: default avatarOleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent af7fff9c

kernel/signal.c

+17 −25
Original line number Diff line number Diff line
@@ -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))

		signal_wake_up(t, sig == SIGKILL);

out:

	if (ret <= 0)

		return ret;



	if (!sigismember(&t->blocked, sig))

		signal_wake_up(t, sig == SIGKILL);

	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);