[PATCH] coredump: speedup SIGKILL sending
With this patch a thread group is killed atomically under ->siglock. This is
faster because we can use sigaddset() instead of force_sig_info() and this is
used in further patches.
Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Acked-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/fs/exec.c b/fs/exec.c
index 80fe7bc..a5c5164 100644
--- a/fs/exec.c
+++ b/fs/exec.c
@@ -1371,17 +1371,24 @@
static void zap_process(struct task_struct *start, int *ptraced)
{
struct task_struct *t;
+ unsigned long flags;
+
+ spin_lock_irqsave(&start->sighand->siglock, flags);
t = start;
do {
if (t != current && t->mm) {
t->mm->core_waiters++;
- force_sig_specific(SIGKILL, t);
+ sigaddset(&t->pending.signal, SIGKILL);
+ signal_wake_up(t, 1);
+
if (unlikely(t->ptrace) &&
unlikely(t->parent->mm == t->mm))
*ptraced = 1;
}
} while ((t = next_thread(t)) != start);
+
+ spin_unlock_irqrestore(&start->sighand->siglock, flags);
}
static void zap_threads (struct mm_struct *mm)