From mboxrd@z Thu Jan 1 00:00:00 1970 From: Nitish Ambastha Subject: [PATCH 1/1] kernel/power/autosleep.c: check for pm_suspend() return before queueing suspend again Date: Mon, 29 Jun 2015 18:04:57 +0530 Message-ID: <1435581297-20271-1-git-send-email-nitish.a@samsung.com> Return-path: Received: from mailout2.samsung.com ([203.254.224.25]:50514 "EHLO mailout2.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750872AbbF2HBY (ORCPT ); Mon, 29 Jun 2015 03:01:24 -0400 Sender: linux-pm-owner@vger.kernel.org List-Id: linux-pm@vger.kernel.org To: rjw@rjwysocki.net, pavel@ucw.cz, len.brown@intel.com, linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org Cc: cpgs@samsung.com, nitish.a@samsung.com, nits.ambastha@gmail.com Prevent tight loop for suspend-resume when some devices failed to suspend If some devices failed to suspend, we monitor this error in try_to_suspend(). pm_suspend() is already an 'int' returning function, how about checking return from pm_suspend() before queueing suspend again? For devices which do not register for pending events, this will prevent tight loop for suspend-resume in suspend abort scenarios due to device suspend failures Signed-off-by: Nitish Ambastha --- kernel/power/autosleep.c | 13 ++++++++++++- 1 file changed, 12 insertions(+), 1 deletion(-) diff --git a/kernel/power/autosleep.c b/kernel/power/autosleep.c index 9012ecf..3923148 100644 --- a/kernel/power/autosleep.c +++ b/kernel/power/autosleep.c @@ -26,6 +26,7 @@ static struct wakeup_source *autosleep_ws; static void try_to_suspend(struct work_struct *work) { unsigned int initial_count, final_count; + int error = 0; if (!pm_get_wakeup_count(&initial_count, true)) goto out; @@ -45,10 +46,20 @@ static void try_to_suspend(struct work_struct *work) if (autosleep_state >= PM_SUSPEND_MAX) hibernate(); else - pm_suspend(autosleep_state); + error = pm_suspend(autosleep_state); mutex_unlock(&autosleep_lock); + if (error) { + /* + * If some devices failed to suspend, its better to wait + * to prevent system from trying to suspend in tight loop + */ + pr_info("PM: suspend returned (%d)\n", error); + schedule_timeout_uninterruptible(HZ / 2); + goto out; + } + if (!pm_get_wakeup_count(&final_count, false)) goto out; -- 1.7.9.5