Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752373AbbDYUKl (ORCPT ); Sat, 25 Apr 2015 16:10:41 -0400 Received: from atrey.karlin.mff.cuni.cz ([195.113.26.193]:37343 "EHLO atrey.karlin.mff.cuni.cz" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750928AbbDYUKj (ORCPT ); Sat, 25 Apr 2015 16:10:39 -0400 Date: Sat, 25 Apr 2015 22:10:34 +0200 From: Pavel Machek To: Jin Qian Cc: "Rafael J. Wysocki" , Len Brown , Greg Kroah-Hartman , linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 2/3] power: increment wakeup_count when save_wakeup_count failed. Message-ID: <20150425201034.GA3008@amd> References: <1429750212-28659-1-git-send-email-jinqian@android.com> <1429750212-28659-3-git-send-email-jinqian@android.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1429750212-28659-3-git-send-email-jinqian@android.com> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2440 Lines: 75 On Wed 2015-04-22 17:50:11, Jin Qian wrote: > user-space aborts suspend attempt if writing wakeup_count failed. > Count the write failure towards wakeup_count. Why should writing wakeup_count fail? Can you make sure it does not happen, instead? Pavel > Signed-off-by: Jin Qian > --- > drivers/base/power/wakeup.c | 17 +++++++++++++++++ > 1 file changed, 17 insertions(+) > > diff --git a/drivers/base/power/wakeup.c b/drivers/base/power/wakeup.c > index f24c622..bdb45f3 100644 > --- a/drivers/base/power/wakeup.c > +++ b/drivers/base/power/wakeup.c > @@ -57,6 +57,8 @@ static LIST_HEAD(wakeup_sources); > > static DECLARE_WAIT_QUEUE_HEAD(wakeup_count_wait_queue); > > +static ktime_t last_read_time; > + > /** > * wakeup_source_prepare - Prepare a new wakeup source for initialization. > * @ws: Wakeup source to prepare. > @@ -771,10 +773,15 @@ void pm_wakeup_clear(void) > bool pm_get_wakeup_count(unsigned int *count, bool block) > { > unsigned int cnt, inpr; > + unsigned long flags; > > if (block) { > DEFINE_WAIT(wait); > > + spin_lock_irqsave(&events_lock, flags); > + last_read_time = ktime_get(); > + spin_unlock_irqrestore(&events_lock, flags); > + > for (;;) { > prepare_to_wait(&wakeup_count_wait_queue, &wait, > TASK_INTERRUPTIBLE); > @@ -806,6 +813,7 @@ bool pm_save_wakeup_count(unsigned int count) > { > unsigned int cnt, inpr; > unsigned long flags; > + struct wakeup_source *ws; > > events_check_enabled = false; > spin_lock_irqsave(&events_lock, flags); > @@ -813,6 +821,15 @@ bool pm_save_wakeup_count(unsigned int count) > if (cnt == count && inpr == 0) { > saved_count = count; > events_check_enabled = true; > + } else { > + rcu_read_lock(); > + list_for_each_entry_rcu(ws, &wakeup_sources, entry) { > + if (ws->active || > + ktime_compare(ws->last_time, last_read_time) > 0) { > + ws->wakeup_count++; > + } > + } > + rcu_read_unlock(); > } > spin_unlock_irqrestore(&events_lock, flags); > return events_check_enabled; -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/