| Message ID | 1491988332-13398-1-git-send-email-j-keerthy@ti.com (mailing list archive) |
|---|---|
| State | Rejected |
| Delegated to: | Zhang Rui |
| Headers | show |
Hey, On Wed, Apr 12, 2017 at 02:42:12PM +0530, Keerthy wrote: > thermal_zone_device_check --> thermal_zone_device_update --> > handle_thermal_trip --> handle_critical_trips --> orderly_poweroff > > The above sequence happens every 250/500 mS based on the configuration. > The orderly_poweroff function is getting called every 250/500 mS. > With a full fledged file system it takes at least 5-10 Seconds to > power off gracefully. > > In that period due to the thermal_zone_device_check triggering > periodically the thermal work queues bombard with > orderly_poweroff calls multiple times eventually leading to > failures in gracefully powering off the system. > > Make sure that orderly_poweroff is called only once. > > Fixes: 0c01ebbfd3caf1d ("Thermal: Remove throttling logic out of thermal_sys.c") Why? how the above commit introduced this issue? > Reported-by: Nishanth Menon <nm@ti.com> > Signed-off-by: Keerthy <j-keerthy@ti.com> > --- > drivers/thermal/thermal_core.c | 4 +++- > 1 file changed, 3 insertions(+), 1 deletion(-) > > diff --git a/drivers/thermal/thermal_core.c b/drivers/thermal/thermal_core.c > index 11f0675..4e68ce0 100644 > --- a/drivers/thermal/thermal_core.c > +++ b/drivers/thermal/thermal_core.c > @@ -326,6 +326,7 @@ static void handle_critical_trips(struct thermal_zone_device *tz, > int trip, enum thermal_trip_type trip_type) > { > int trip_temp; > + static bool power_off_triggered; > I am not convinced this change does what you say it does.. > tz->ops->get_trip_temp(tz, trip, &trip_temp); > > @@ -338,11 +339,12 @@ static void handle_critical_trips(struct thermal_zone_device *tz, > if (tz->ops->notify) > tz->ops->notify(tz, trip, trip_type); > > - if (trip_type == THERMAL_TRIP_CRITICAL) { > + if (trip_type == THERMAL_TRIP_CRITICAL && !power_off_triggered) { > dev_emerg(&tz->device, > "critical temperature reached(%d C),shutting down\n", > tz->temperature / 1000); > orderly_poweroff(true); Imagine you have two zones about to enter critical path. thermal zone 0 first gets into critical, and at this line (btween orderly_poweroff() and you set your flag), it gets preempted. Then thermal zone 1 also enters the critical path, then happens to be scheduled, you essentially end up still calling orderly_poweroff() twice, which is what this patch is supposed to avoid. You better simply use a lock to serialize code execution. BR, > + power_off_triggered = true; > } > } > > -- > 1.9.1 >
On Thursday 13 April 2017 10:36 AM, Eduardo Valentin wrote: > Hey, > > On Wed, Apr 12, 2017 at 02:42:12PM +0530, Keerthy wrote: >> thermal_zone_device_check --> thermal_zone_device_update --> >> handle_thermal_trip --> handle_critical_trips --> orderly_poweroff >> >> The above sequence happens every 250/500 mS based on the configuration. >> The orderly_poweroff function is getting called every 250/500 mS. >> With a full fledged file system it takes at least 5-10 Seconds to >> power off gracefully. >> >> In that period due to the thermal_zone_device_check triggering >> periodically the thermal work queues bombard with >> orderly_poweroff calls multiple times eventually leading to >> failures in gracefully powering off the system. >> >> Make sure that orderly_poweroff is called only once. >> >> Fixes: 0c01ebbfd3caf1d ("Thermal: Remove throttling logic out of thermal_sys.c") > > Why? how the above commit introduced this issue? git blame showed me that. I can remove this. Let me know if you have the right commit that introduced this. > >> Reported-by: Nishanth Menon <nm@ti.com> >> Signed-off-by: Keerthy <j-keerthy@ti.com> >> --- >> drivers/thermal/thermal_core.c | 4 +++- >> 1 file changed, 3 insertions(+), 1 deletion(-) >> >> diff --git a/drivers/thermal/thermal_core.c b/drivers/thermal/thermal_core.c >> index 11f0675..4e68ce0 100644 >> --- a/drivers/thermal/thermal_core.c >> +++ b/drivers/thermal/thermal_core.c >> @@ -326,6 +326,7 @@ static void handle_critical_trips(struct thermal_zone_device *tz, >> int trip, enum thermal_trip_type trip_type) >> { >> int trip_temp; >> + static bool power_off_triggered; >> > > I am not convinced this change does what you say it does.. > >> tz->ops->get_trip_temp(tz, trip, &trip_temp); >> >> @@ -338,11 +339,12 @@ static void handle_critical_trips(struct thermal_zone_device *tz, >> if (tz->ops->notify) >> tz->ops->notify(tz, trip, trip_type); >> >> - if (trip_type == THERMAL_TRIP_CRITICAL) { >> + if (trip_type == THERMAL_TRIP_CRITICAL && !power_off_triggered) { >> dev_emerg(&tz->device, >> "critical temperature reached(%d C),shutting down\n", >> tz->temperature / 1000); >> orderly_poweroff(true); > > Imagine you have two zones about to enter critical path. thermal zone 0 > first gets into critical, and at this line (btween orderly_poweroff() > and you set your flag), it gets preempted. Then thermal zone 1 also > enters the critical path, then happens to be scheduled, you essentially > end up still calling orderly_poweroff() twice, which is what this patch > is supposed to avoid. > > You better simply use a lock to serialize code execution. Okay understood. Will do it in the next version. > > BR, > >> + power_off_triggered = true; >> } >> } >> >> -- >> 1.9.1 >>
diff --git a/drivers/thermal/thermal_core.c b/drivers/thermal/thermal_core.c index 11f0675..4e68ce0 100644 --- a/drivers/thermal/thermal_core.c +++ b/drivers/thermal/thermal_core.c @@ -326,6 +326,7 @@ static void handle_critical_trips(struct thermal_zone_device *tz, int trip, enum thermal_trip_type trip_type) { int trip_temp; + static bool power_off_triggered; tz->ops->get_trip_temp(tz, trip, &trip_temp); @@ -338,11 +339,12 @@ static void handle_critical_trips(struct thermal_zone_device *tz, if (tz->ops->notify) tz->ops->notify(tz, trip, trip_type); - if (trip_type == THERMAL_TRIP_CRITICAL) { + if (trip_type == THERMAL_TRIP_CRITICAL && !power_off_triggered) { dev_emerg(&tz->device, "critical temperature reached(%d C),shutting down\n", tz->temperature / 1000); orderly_poweroff(true); + power_off_triggered = true; } }
thermal_zone_device_check --> thermal_zone_device_update --> handle_thermal_trip --> handle_critical_trips --> orderly_poweroff The above sequence happens every 250/500 mS based on the configuration. The orderly_poweroff function is getting called every 250/500 mS. With a full fledged file system it takes at least 5-10 Seconds to power off gracefully. In that period due to the thermal_zone_device_check triggering periodically the thermal work queues bombard with orderly_poweroff calls multiple times eventually leading to failures in gracefully powering off the system. Make sure that orderly_poweroff is called only once. Fixes: 0c01ebbfd3caf1d ("Thermal: Remove throttling logic out of thermal_sys.c") Reported-by: Nishanth Menon <nm@ti.com> Signed-off-by: Keerthy <j-keerthy@ti.com> --- drivers/thermal/thermal_core.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)