From mboxrd@z Thu Jan 1 00:00:00 1970 From: Pavel Machek Subject: Re: S3 and sigwait (was Re: 2.6.13-rc3: swsusp works (TP 600X)) Date: Mon, 1 Aug 2005 09:09:26 +0200 Message-ID: <20050801070926.GI27580@elf.ucw.cz> References: <20050730103034.GC1942@elf.ucw.cz> <1122879094.3285.2.camel@linux-hp.sh.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <1122879094.3285.2.camel-ECwVeV2eNyQD0+JXs3kMbRL4W9x8LtSr@public.gmane.org> Sender: acpi-devel-admin-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org Errors-To: acpi-devel-admin-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , List-Archive: To: Shaohua Li Cc: Sanjoy Mahajan , linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, acpi-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org List-Id: linux-acpi@vger.kernel.org Hi! > > If you think it is a linux bug, can you produce small test case doing > > just the sigwait, and post it on l-k with big title "sigwait() breaks > > when straced, and on suspend"? > > > > That way it is going to get some attetion, and you'll get either > > documentation or kernel fixed. > Looks like a linux bug to me. The refrigerator fake signal waked the > task up and without restart for the sigwait case. How about below > patch: Is there chance to fix strace case, too? sigwait() is broken in more than one way it seems... Pavel > linux-2.6.13-rc4-root/kernel/signal.c | 11 ++++++++++- > 1 files changed, 10 insertions(+), 1 deletion(-) > > diff -puN kernel/signal.c~sigwait-suspend-resume kernel/signal.c > --- linux-2.6.13-rc4/kernel/signal.c~sigwait-suspend-resume 2005-08-01 14:00:39.089460688 +0800 > +++ linux-2.6.13-rc4-root/kernel/signal.c 2005-08-01 14:30:13.821660384 +0800 > @@ -2188,6 +2188,7 @@ sys_rt_sigtimedwait(const sigset_t __use > struct timespec ts; > siginfo_t info; > long timeout = 0; > + int recover = 0; > > /* XXX: Don't preclude handling different sized sigset_t's. */ > if (sigsetsize != sizeof(sigset_t)) > @@ -2225,15 +2226,23 @@ sys_rt_sigtimedwait(const sigset_t __use > * be awakened when they arrive. */ > current->real_blocked = current->blocked; > sigandsets(¤t->blocked, ¤t->blocked, &these); > +do_recover: > recalc_sigpending(); > spin_unlock_irq(¤t->sighand->siglock); > > current->state = TASK_INTERRUPTIBLE; > timeout = schedule_timeout(timeout); > > - try_to_freeze(); > + if (try_to_freeze()) > + recover = 1; Can't you just goto do_recover here? > spin_lock_irq(¤t->sighand->siglock); > sig = dequeue_signal(current, &these, &info); > + if (!sig && recover) { > + if (timeout == 0) > + timeout = MAX_SCHEDULE_TIMEOUT; > + recover = 0; > + goto do_recover; > + } > current->blocked = current->real_blocked; > siginitset(¤t->real_blocked, 0); > recalc_sigpending(); > _ > -- if you have sharp zaurus hardware you don't need... you know my address ------------------------------------------------------- SF.Net email is sponsored by: Discover Easy Linux Migration Strategies from IBM. Find simple to follow Roadmaps, straightforward articles, informative Webcasts and more! Get everything you need to get up to speed, fast. http://ads.osdn.com/?ad_id=7477&alloc_id=16492&op=click