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 <xemul@openvz.org>
Cc: Roland McGrath <roland@redhat.com>
Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/kernel/signal.c b/kernel/signal.c
index 772aa01..fb8ffd4 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -668,6 +668,14 @@
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 @@
out_set:
sigaddset(&signals->signal, sig);
- return 0;
+ return 1;
}
int print_fatal_signals;
@@ -761,26 +769,18 @@
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 @@
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);