Re: [PATCH] Software suspend and recalc sigpending bug fix

[Kirill Korotaev <dev@sw.ru>]

>>This patch fixes recalc_sigpending() to work correctly
>>with tasks which are being freezed. The problem is that
>>freeze_processes() sets PF_FREEZE and TIF_SIGPENDING
>>flags on tasks, but recalc_sigpending() called from
>>e.g. sys_rt_sigtimedwait or any other kernel place
>>will clear TIF_SIGPENDING due to no pending signals queued
>>and the tasks won't be freezed until it recieves a real signal
>>or freezed_processes() fail due to timeout.
>>
>>Signed-Off-By: Kirill Korotaev <dev@sw.ru>
>>Signed-Off-By: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
> 
> 
> This should fix our problems with mysqld, right? Yes, patch looks good
> (modulo missing whitespace around &)). I'll apply it to my tree. (Or
> andrew, if you prefer, just take it...

Another cleanup idea in swsusp: it would be nice if all such checks for 
PF_FREEZE were wrapped in inline function 
is_task_freezing()/any_thing_else, to make freeze code disappear when 
CONFIG_PM/CONFIG_SOFTWARE_SUSPEND is off...

Kirill

> 								Pavel
> 
> 
>>--- ./kernel/signal.c.freezesigrec	2005-05-10 16:10:40.000000000 +0400
>>+++ ./kernel/signal.c	2005-05-10 18:10:08.000000000 +0400
>>@@ -212,6 +212,7 @@ static inline int has_pending_signals(si
>> fastcall void recalc_sigpending_tsk(struct task_struct *t)
>> {
>> 	if (t->signal->group_stop_count > 0 ||
>>+	    (t->flags&PF_FREEZE) ||
>> 	    PENDING(&t->pending, &t->blocked) ||
>> 	    PENDING(&t->signal->shared_pending, &t->blocked))
>> 		set_tsk_thread_flag(t, TIF_SIGPENDING);
> 
> 
>