From: Oleg Nesterov Every time we set SIGNAL_GROUP_EXIT or clear SIGNAL_STOP_DEQUEUED we also reset ->group_stop_count. This means that the SIGNAL_GROUP_EXIT check in handle_group_stop() is not needed, and do_signal_stop() should check SIGNAL_STOP_DEQUEUED only when ->group_stop_count == 0. With these changes handle_group_stop() becomes the subset of do_signal_stop(), we can kill it and use do_signal_stop() instead. Also, a preparation for the next patch. Signed-off-by: Oleg Nesterov Cc: Davide Libenzi Cc: Ingo Molnar Cc: Linus Torvalds Cc: Robin Holt Cc: Roland McGrath Signed-off-by: Andrew Morton --- kernel/signal.c | 43 +++++-------------------------------------- 1 file changed, 5 insertions(+), 38 deletions(-) diff -puN kernel/signal.c~remove-handle_group_stop-in-favor-of-do_signal_stop kernel/signal.c --- a/kernel/signal.c~remove-handle_group_stop-in-favor-of-do_signal_stop +++ a/kernel/signal.c @@ -1682,9 +1682,6 @@ static int do_signal_stop(int signr) struct signal_struct *sig = current->signal; int stop_count; - if (!likely(sig->flags & SIGNAL_STOP_DEQUEUED)) - return 0; - if (sig->group_stop_count > 0) { /* * There is a group stop in progress. We don't need to @@ -1692,12 +1689,14 @@ static int do_signal_stop(int signr) */ stop_count = --sig->group_stop_count; } else { + struct task_struct *t; + + if (!likely(sig->flags & SIGNAL_STOP_DEQUEUED)) + return 0; /* * There is no group stop already in progress. * We must initiate one now. */ - struct task_struct *t; - sig->group_exit_code = signr; stop_count = 0; @@ -1725,38 +1724,6 @@ static int do_signal_stop(int signr) return 1; } -/* - * Do appropriate magic when group_stop_count > 0. - * We return nonzero if we stopped, after releasing the siglock. - * We return zero if we still hold the siglock and should look - * for another signal without checking group_stop_count again. - */ -static int handle_group_stop(void) -{ - int stop_count; - - if (current->signal->flags & SIGNAL_GROUP_EXIT) - /* - * Group stop is so another thread can do a core dump, - * or else we are racing against a death signal. - * Just punt the stop so we can get the next signal. - */ - return 0; - - /* - * There is a group stop in progress. We stop - * without any associated signal being in our queue. - */ - stop_count = --current->signal->group_stop_count; - if (stop_count == 0) - current->signal->flags = SIGNAL_STOP_STOPPED; - current->exit_code = current->signal->group_exit_code; - set_current_state(TASK_STOPPED); - spin_unlock_irq(¤t->sighand->siglock); - finish_stop(stop_count); - return 1; -} - int get_signal_to_deliver(siginfo_t *info, struct k_sigaction *return_ka, struct pt_regs *regs, void *cookie) { @@ -1771,7 +1738,7 @@ relock: struct k_sigaction *ka; if (unlikely(current->signal->group_stop_count > 0) && - handle_group_stop()) + do_signal_stop(0)) goto relock; signr = dequeue_signal(current, mask, info); _