2007-08-02 22:37:20

by Oleg Nesterov

Subject: [PATCH] do_sigaction: remove now unneeded recalc_sigpending()

With the recent changes, do_sigaction()->recalc_sigpending_and_wake() can
never clear TIF_SIGPENDING. Instead, it can set this flag and wake up the
thread without any reason. Harmless, but unneeded and wastes CPU.

Signed-off-by: Oleg Nesterov <[email protected]>

--- t/kernel/signal.c~ 2007-08-03 02:26:30.000000000 +0400
+++ t/kernel/signal.c 2007-08-03 02:28:50.000000000 +0400
@@ -2342,7 +2342,6 @@ int do_sigaction(int sig, struct k_sigac
rm_from_queue_full(&mask, &t->signal->shared_pending);
do {
rm_from_queue_full(&mask, &t->pending);
- recalc_sigpending_and_wake(t);
t = next_thread(t);
} while (t != current);
}

2007-08-02 22:41:08

by Roland McGrath

Subject: Re: [PATCH] do_sigaction: remove now unneeded recalc_sigpending()

> With the recent changes, do_sigaction()->recalc_sigpending_and_wake() can
> never clear TIF_SIGPENDING. Instead, it can set this flag and wake up the
> thread without any reason. Harmless, but unneeded and wastes CPU.
>
> Signed-off-by: Oleg Nesterov <[email protected]>

ACK. (We agreed months ago this was the thing to do.)


Thanks,
Roland