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 <[email protected]> --- v2: Rearranged code to make wait entry shared with existing one as suggested by Pavel Machek <[email protected]> Corrected log level from pr_info to pr_err for failure log Added return check for hibernate() kernel/power/autosleep.c | 23 ++++++++++++++++------- 1 file changed, 16 insertions(+), 7 deletions(-) diff --git a/kernel/power/autosleep.c b/kernel/power/autosleep.c index 9012ecf..1a86698 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; @@ -43,22 +44,30 @@ static void try_to_suspend(struct work_struct *work) return; } if (autosleep_state >= PM_SUSPEND_MAX) - hibernate(); + error = hibernate(); else - pm_suspend(autosleep_state); + error = pm_suspend(autosleep_state); mutex_unlock(&autosleep_lock); + if (error) { + pr_err("PM: suspend returned (%d)\n", error); + goto wait; + } + if (!pm_get_wakeup_count(&final_count, false)) goto out; + if (final_count != initial_count) + goto out; + + wait: /* - * If the wakeup occured for an unknown reason, wait to prevent the - * system from trying to suspend and waking up in a tight loop. + * If some devices failed to suspend or if the wakeup ocurred + * for an unknown reason, wait to prevent the system from + * trying to suspend and waking up in a tight loop. */ - if (final_count == initial_count) - schedule_timeout_uninterruptible(HZ / 2); - + schedule_timeout_uninterruptible(HZ / 2); out: queue_up_suspend_work(); } -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
