[PATCH v2 -next 0/2] PM: suspend: Optimized suspend is fail returned by wakeup

[PATCH v2 -next 0/2] PM: suspend: Optimized suspend is fail returned by wakeup

[xiongxin]

Changes in v2:
* fix a build test ERROR reported by kernel test robot.
* Increase the initial value of the pm_suspend_target_state variable to
  prevent the situation where it was not assigned before the call from
  freeze_process().

Cover letter from v1:

When the suspend process is executed from the /sys/power/state entry,
the pm_wakeup_clear() signal is cleared in advance, and the wakeup
signal can be captured to fail the suspend process when the suspend
process is notified by the notifier;

Expanding the scope of the pm_suspend_target_state variable also allows
the device driver to know that the system has entered the suspend
process earlier.

xiongxin (2):
  PM: suspend: expand the assignment scope of the
    pm_suspend_target_state
  PM: suspend: advanced pm_wakeup_clear() for normal suspend/hibernate

 kernel/power/process.c |  5 ++++-
 kernel/power/suspend.c | 15 ++++++++++++++-
 2 files changed, 18 insertions(+), 2 deletions(-)

-- 
2.25.1


No virus found
		Checked by Hillstone Network AntiVirus

[PATCH v2 -next 1/2] PM: suspend: expand the assignment scope of the pm_suspend_target_state

[xiongxin]

The pm_suspend_target_state variable can be used as a suspend state
identifier and given to the specific device driver as a code judgment;

Because the suspend_prepare() function is time-consuming for the
operation of freezing processes, and this stage is actually in the suspend
stage, it is necessary to expand the scope of the pm_suspend_target_state
variable to be assigned to the suspend state at enter_state() function;

Another reason is that the specific device driver can locate whether it is
in the suspend state based on this variable, so as to determine the
validity of its wake-up source.

Signed-off-by: xiongxin <xiongxin@kylinos.cn>
---
 kernel/power/suspend.c | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/kernel/power/suspend.c b/kernel/power/suspend.c
index 827075944d28..4cfa464600bf 100644
--- a/kernel/power/suspend.c
+++ b/kernel/power/suspend.c
@@ -48,7 +48,7 @@ const char *mem_sleep_states[PM_SUSPEND_MAX];
 
 suspend_state_t mem_sleep_current = PM_SUSPEND_TO_IDLE;
 suspend_state_t mem_sleep_default = PM_SUSPEND_MAX;
-suspend_state_t pm_suspend_target_state;
+suspend_state_t pm_suspend_target_state = PM_SUSPEND_ON;
 EXPORT_SYMBOL_GPL(pm_suspend_target_state);
 
 unsigned int pm_suspend_global_flags;
@@ -564,6 +564,12 @@ static int enter_state(suspend_state_t state)
 	if (state == PM_SUSPEND_TO_IDLE)
 		s2idle_begin();
 
+	/*
+	 * Expand the scope of suspend state for suspend operations
+	 * performed from the /sys/power/state entry.
+	 */
+	pm_suspend_target_state = state;
+
 	if (sync_on_suspend_enabled) {
 		trace_suspend_resume(TPS("sync_filesystems"), 0, true);
 		ksys_sync_helper();
@@ -590,6 +596,7 @@ static int enter_state(suspend_state_t state)
 	pm_pr_dbg("Finishing wakeup.\n");
 	suspend_finish();
  Unlock:
+	pm_suspend_target_state = PM_SUSPEND_ON;
 	mutex_unlock(&system_transition_mutex);
 	return error;
 }
-- 
2.25.1


No virus found
		Checked by Hillstone Network AntiVirus

[PATCH v2 -next 2/2] PM: suspend: advanced pm_wakeup_clear() for normal suspend/hibernate

[xiongxin]

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
returns;

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 <xiongxin@kylinos.cn>
---
 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)
 		atomic_inc(&system_freezing_cnt);
 
-	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 4cfa464600bf..2a82db57adc9 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);
-- 
2.25.1


No virus found
		Checked by Hillstone Network AntiVirus