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Subject[PATCH -next 2/2] PM: suspend: advanced pm_wakeup_clear() for normal suspend/hibernate
pm_wakeup_clear() will clear the wakeup source, which can ensure that it
is not disturbed by useless wakeup signals when doing suspend/hibernate;

At the beginning of the suspend/hibernate process, the notifier
mechanism is used to notify other device drivers. This action is
time-consuming (second-level time-consuming). If the process fails due
to the received wakeup signal during the execution of these functions,
it can better improve the experience of failing suspend/hibernate

Therefore, it is recommended here that for the suspend/hibernate process
normally called from /sys/power/state, the pm_wakeup_clear() function
should be brought before the notifier call; for the freeze_process()
function called from other places, the original logic is kept;

The pm_suspend_target_state variable is used here to identify whether the
suspend process is going normally.

Signed-off-by: xiongxin <>
kernel/power/process.c | 5 ++++-
kernel/power/suspend.c | 6 ++++++
2 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/kernel/power/process.c b/kernel/power/process.c
index 3068601e585a..3fde0240b3d1 100644
--- a/kernel/power/process.c
+++ b/kernel/power/process.c
@@ -131,7 +131,10 @@ int freeze_processes(void)
if (!pm_freezing)

- pm_wakeup_clear(0);
+ if (pm_suspend_target_state != PM_SUSPEND_ON)
+ pm_wakeup_clear(1);
+ else
+ pm_wakeup_clear(0);
pr_info("Freezing user space processes ... ");
pm_freezing = true;
error = try_to_freeze_tasks(true);
diff --git a/kernel/power/suspend.c b/kernel/power/suspend.c
index c754b084ec03..f4259f6c1cc2 100644
--- a/kernel/power/suspend.c
+++ b/kernel/power/suspend.c
@@ -569,6 +569,12 @@ static int enter_state(suspend_state_t state)
* performed from the /sys/power/state entry.
pm_suspend_target_state = state;
+ /*
+ * Put pm_wakeup_clear() before the notifier notification chain to
+ * optimize in the suspend process, the wakeup signal can interrupt
+ * the suspend in advance and fail to return.
+ */
+ pm_wakeup_clear(0);

if (sync_on_suspend_enabled) {
trace_suspend_resume(TPS("sync_filesystems"), 0, true);

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