diff mbox

[RFC,3/3] thermal: trace: Trace when temperature is above a trip point

Message ID 9hhionqvbbx.fsf@arm.com (mailing list archive)
State RFC, archived
Headers show

Commit Message

Punit Agrawal June 24, 2014, 10:41 a.m. UTC
"Javi Merino" <javi.merino@arm.com> writes:

> Hi Punit,
>
> On Wed, Jun 11, 2014 at 12:31:44PM +0100, Punit Agrawal wrote:
>> Create a new event to trace when the temperature is above a trip
>> point. Use the trace-point when handling non-critical and critical
>> trip pionts.
>> 
>> Cc: Zhang Rui <rui.zhang@intel.com>
>> Cc: Eduardo Valentin <edubezval@gmail.com>
>> Cc: Steven Rostedt <rostedt@goodmis.org>
>> Cc: Frederic Weisbecker <fweisbec@gmail.com>
>> Cc: Ingo Molnar <mingo@redhat.com>
>> Signed-off-by: Punit Agrawal <punit.agrawal@arm.com>
>> ---
>> Hi Steven,
>> 
>> I am facing an issue with partial trace being emitted when using
>> __print_symbolic in this patch. 
>> 
>> When the trip_type is THERMAL_TRIP_ACTIVE (i.e., the first value in
>> the symbol map), the emitted trace contains the corresponding string
>> ("active"). But for other values of trip_type an empty string is
>> emitted in the trace.
>> 
>> I've looked at other uses of __print_symbolic in the kernel and don't
>> see any difference in usage. Do you know what could be causing this or
>> alternately have any pointers on how to debug this behaviour?
>> 
>> Thanks.
>> Punit
>> 
>>  drivers/thermal/fair_share.c   |    7 ++++++-
>>  drivers/thermal/step_wise.c    |    5 ++++-
>>  drivers/thermal/thermal_core.c |    2 ++
>>  include/trace/events/thermal.h |   30 ++++++++++++++++++++++++++++++
>>  4 files changed, 42 insertions(+), 2 deletions(-)
>> 
>> diff --git a/drivers/thermal/fair_share.c b/drivers/thermal/fair_share.c
>> index 944ba2f..2cddd68 100644
>> --- a/drivers/thermal/fair_share.c
>> +++ b/drivers/thermal/fair_share.c
>> @@ -23,6 +23,7 @@
>>   */
>>  
>>  #include <linux/thermal.h>
>> +#include <trace/events/thermal.h>
>>  
>>  #include "thermal_core.h"
>>  
>> @@ -34,14 +35,18 @@ static int get_trip_level(struct thermal_zone_device *tz)
>>  {
>>  	int count = 0;
>>  	unsigned long trip_temp;
>> +	enum thermal_trip_type trip_type;
>>  
>>  	if (tz->trips == 0 || !tz->ops->get_trip_temp)
>>  		return 0;
>>  
>>  	for (count = 0; count < tz->trips; count++) {
>>  		tz->ops->get_trip_temp(tz, count, &trip_temp);
>> -		if (tz->temperature < trip_temp)
>> +		if (tz->temperature < trip_temp) {
>> +			tz->ops->get_trip_type(tz, count, &trip_type);
>> +			trace_thermal_zone_trip(tz, count, trip_type);
>
> This should be outside the if condition.  You want to report when trip
> points have been hit, like in the step_wise code below.
>

It turned out to be a bit more subtle than moving the trace outside the
if. I have the below fixup with an added comment. Let me know if that
doesn't solve the problem.

-- >8 --
Subject: [PATCH] fixup! thermal: trace: Trace when temperature is above a
 trip point

---
 drivers/thermal/fair_share.c |   15 +++++++++++----
 1 file changed, 11 insertions(+), 4 deletions(-)

Comments

Javi Merino June 25, 2014, 1:26 p.m. UTC | #1
On Tue, Jun 24, 2014 at 11:41:38AM +0100, Punit Agrawal wrote:
> "Javi Merino" <javi.merino@arm.com> writes:
> 
> > Hi Punit,
> >
> > On Wed, Jun 11, 2014 at 12:31:44PM +0100, Punit Agrawal wrote:
> >> Create a new event to trace when the temperature is above a trip
> >> point. Use the trace-point when handling non-critical and critical
> >> trip pionts.
> >> 
> >> Cc: Zhang Rui <rui.zhang@intel.com>
> >> Cc: Eduardo Valentin <edubezval@gmail.com>
> >> Cc: Steven Rostedt <rostedt@goodmis.org>
> >> Cc: Frederic Weisbecker <fweisbec@gmail.com>
> >> Cc: Ingo Molnar <mingo@redhat.com>
> >> Signed-off-by: Punit Agrawal <punit.agrawal@arm.com>
> >> ---
> >> Hi Steven,
> >> 
> >> I am facing an issue with partial trace being emitted when using
> >> __print_symbolic in this patch. 
> >> 
> >> When the trip_type is THERMAL_TRIP_ACTIVE (i.e., the first value in
> >> the symbol map), the emitted trace contains the corresponding string
> >> ("active"). But for other values of trip_type an empty string is
> >> emitted in the trace.
> >> 
> >> I've looked at other uses of __print_symbolic in the kernel and don't
> >> see any difference in usage. Do you know what could be causing this or
> >> alternately have any pointers on how to debug this behaviour?
> >> 
> >> Thanks.
> >> Punit
> >> 
> >>  drivers/thermal/fair_share.c   |    7 ++++++-
> >>  drivers/thermal/step_wise.c    |    5 ++++-
> >>  drivers/thermal/thermal_core.c |    2 ++
> >>  include/trace/events/thermal.h |   30 ++++++++++++++++++++++++++++++
> >>  4 files changed, 42 insertions(+), 2 deletions(-)
> >> 
> >> diff --git a/drivers/thermal/fair_share.c b/drivers/thermal/fair_share.c
> >> index 944ba2f..2cddd68 100644
> >> --- a/drivers/thermal/fair_share.c
> >> +++ b/drivers/thermal/fair_share.c
> >> @@ -23,6 +23,7 @@
> >>   */
> >>  
> >>  #include <linux/thermal.h>
> >> +#include <trace/events/thermal.h>
> >>  
> >>  #include "thermal_core.h"
> >>  
> >> @@ -34,14 +35,18 @@ static int get_trip_level(struct thermal_zone_device *tz)
> >>  {
> >>  	int count = 0;
> >>  	unsigned long trip_temp;
> >> +	enum thermal_trip_type trip_type;
> >>  
> >>  	if (tz->trips == 0 || !tz->ops->get_trip_temp)
> >>  		return 0;
> >>  
> >>  	for (count = 0; count < tz->trips; count++) {
> >>  		tz->ops->get_trip_temp(tz, count, &trip_temp);
> >> -		if (tz->temperature < trip_temp)
> >> +		if (tz->temperature < trip_temp) {
> >> +			tz->ops->get_trip_type(tz, count, &trip_type);
> >> +			trace_thermal_zone_trip(tz, count, trip_type);
> >
> > This should be outside the if condition.  You want to report when trip
> > points have been hit, like in the step_wise code below.
> >
> 
> It turned out to be a bit more subtle than moving the trace outside the
> if.

True, it was more difficult than what I said.  

>     I have the below fixup with an added comment. Let me know if that
> doesn't solve the problem.

I don't have a reproducer, I just spotted it while reading the code.
The below fix seems to be the right thing.

> -- >8 --
> Subject: [PATCH] fixup! thermal: trace: Trace when temperature is above a
>  trip point
> 
> ---
>  drivers/thermal/fair_share.c |   15 +++++++++++----
>  1 file changed, 11 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/thermal/fair_share.c b/drivers/thermal/fair_share.c
> index 2cddd68..6e0a3fb 100644
> --- a/drivers/thermal/fair_share.c
> +++ b/drivers/thermal/fair_share.c
> @@ -42,12 +42,19 @@ static int get_trip_level(struct thermal_zone_device *tz)
>  
>  	for (count = 0; count < tz->trips; count++) {
>  		tz->ops->get_trip_temp(tz, count, &trip_temp);
> -		if (tz->temperature < trip_temp) {
> -			tz->ops->get_trip_type(tz, count, &trip_type);
> -			trace_thermal_zone_trip(tz, count, trip_type);
> +		if (tz->temperature < trip_temp)
>  			break;
> -		}
>  	}
> +
> +	/*
> +	 * count > 0 only if temperature is greater than first trip
> +	 * point, in which case, trip_point = count - 1
> +	 */
> +	if (count > 0) {
> +		tz->ops->get_trip_type(tz, count - 1, &trip_type);
> +		trace_thermal_zone_trip(tz, count - 1, trip_type);
> +	}
> +
>  	return count;
>  }
>  
> -- 
> 1.7.10.4

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Eduardo Valentin July 25, 2014, 2:11 p.m. UTC | #2
Punit,

On Tue, Jun 24, 2014 at 6:41 AM, Punit Agrawal <punit.agrawal@arm.com> wrote:
> "Javi Merino" <javi.merino@arm.com> writes:
>
>> Hi Punit,
>>
>> On Wed, Jun 11, 2014 at 12:31:44PM +0100, Punit Agrawal wrote:
>>> Create a new event to trace when the temperature is above a trip
>>> point. Use the trace-point when handling non-critical and critical
>>> trip pionts.
>>>
>>> Cc: Zhang Rui <rui.zhang@intel.com>
>>> Cc: Eduardo Valentin <edubezval@gmail.com>
>>> Cc: Steven Rostedt <rostedt@goodmis.org>
>>> Cc: Frederic Weisbecker <fweisbec@gmail.com>
>>> Cc: Ingo Molnar <mingo@redhat.com>
>>> Signed-off-by: Punit Agrawal <punit.agrawal@arm.com>
>>> ---
>>> Hi Steven,
>>>
>>> I am facing an issue with partial trace being emitted when using
>>> __print_symbolic in this patch.
>>>
>>> When the trip_type is THERMAL_TRIP_ACTIVE (i.e., the first value in
>>> the symbol map), the emitted trace contains the corresponding string
>>> ("active"). But for other values of trip_type an empty string is
>>> emitted in the trace.
>>>
>>> I've looked at other uses of __print_symbolic in the kernel and don't
>>> see any difference in usage. Do you know what could be causing this or
>>> alternately have any pointers on how to debug this behaviour?
>>>
>>> Thanks.
>>> Punit
>>>
>>>  drivers/thermal/fair_share.c   |    7 ++++++-
>>>  drivers/thermal/step_wise.c    |    5 ++++-
>>>  drivers/thermal/thermal_core.c |    2 ++
>>>  include/trace/events/thermal.h |   30 ++++++++++++++++++++++++++++++
>>>  4 files changed, 42 insertions(+), 2 deletions(-)
>>>
>>> diff --git a/drivers/thermal/fair_share.c b/drivers/thermal/fair_share.c
>>> index 944ba2f..2cddd68 100644
>>> --- a/drivers/thermal/fair_share.c
>>> +++ b/drivers/thermal/fair_share.c
>>> @@ -23,6 +23,7 @@
>>>   */
>>>
>>>  #include <linux/thermal.h>
>>> +#include <trace/events/thermal.h>
>>>
>>>  #include "thermal_core.h"
>>>
>>> @@ -34,14 +35,18 @@ static int get_trip_level(struct thermal_zone_device *tz)
>>>  {
>>>      int count = 0;
>>>      unsigned long trip_temp;
>>> +    enum thermal_trip_type trip_type;
>>>
>>>      if (tz->trips == 0 || !tz->ops->get_trip_temp)
>>>              return 0;
>>>
>>>      for (count = 0; count < tz->trips; count++) {
>>>              tz->ops->get_trip_temp(tz, count, &trip_temp);
>>> -            if (tz->temperature < trip_temp)
>>> +            if (tz->temperature < trip_temp) {
>>> +                    tz->ops->get_trip_type(tz, count, &trip_type);
>>> +                    trace_thermal_zone_trip(tz, count, trip_type);
>>
>> This should be outside the if condition.  You want to report when trip
>> points have been hit, like in the step_wise code below.
>>
>
> It turned out to be a bit more subtle than moving the trace outside the
> if. I have the below fixup with an added comment. Let me know if that
> doesn't solve the problem.
>
> -- >8 --
> Subject: [PATCH] fixup! thermal: trace: Trace when temperature is above a
>  trip point

Can you please repost the patch with the fixup merged?



Cheers,

>
> ---
>  drivers/thermal/fair_share.c |   15 +++++++++++----
>  1 file changed, 11 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/thermal/fair_share.c b/drivers/thermal/fair_share.c
> index 2cddd68..6e0a3fb 100644
> --- a/drivers/thermal/fair_share.c
> +++ b/drivers/thermal/fair_share.c
> @@ -42,12 +42,19 @@ static int get_trip_level(struct thermal_zone_device *tz)
>
>         for (count = 0; count < tz->trips; count++) {
>                 tz->ops->get_trip_temp(tz, count, &trip_temp);
> -               if (tz->temperature < trip_temp) {
> -                       tz->ops->get_trip_type(tz, count, &trip_type);
> -                       trace_thermal_zone_trip(tz, count, trip_type);
> +               if (tz->temperature < trip_temp)
>                         break;
> -               }
>         }
> +
> +       /*
> +        * count > 0 only if temperature is greater than first trip
> +        * point, in which case, trip_point = count - 1
> +        */
> +       if (count > 0) {
> +               tz->ops->get_trip_type(tz, count - 1, &trip_type);
> +               trace_thermal_zone_trip(tz, count - 1, trip_type);
> +       }
> +
>         return count;
>  }
>
> --
> 1.7.10.4
>
>>>                      break;
>>> +            }
>>>      }
>>>      return count;
>>>  }
>>> diff --git a/drivers/thermal/step_wise.c b/drivers/thermal/step_wise.c
>>> index f251521..3b54c2c 100644
>>> --- a/drivers/thermal/step_wise.c
>>> +++ b/drivers/thermal/step_wise.c
>>> @@ -23,6 +23,7 @@
>>>   */
>>>
>>>  #include <linux/thermal.h>
>>> +#include <trace/events/thermal.h>
>>>
>>>  #include "thermal_core.h"
>>>
>>> @@ -129,8 +130,10 @@ static void thermal_zone_trip_update(struct thermal_zone_device *tz, int trip)
>>>
>>>      trend = get_tz_trend(tz, trip);
>>>
>>> -    if (tz->temperature >= trip_temp)
>>> +    if (tz->temperature >= trip_temp) {
>>>              throttle = true;
>>> +            trace_thermal_zone_trip(tz, trip, trip_type);
>>> +    }
>>>
>>>      dev_dbg(&tz->device, "Trip%d[type=%d,temp=%ld]:trend=%d,throttle=%d\n",
>>>                              trip, trip_type, trip_temp, trend, throttle);
>>> diff --git a/drivers/thermal/thermal_core.c b/drivers/thermal/thermal_core.c
>>> index c74c78d..454884a 100644
>>> --- a/drivers/thermal/thermal_core.c
>>> +++ b/drivers/thermal/thermal_core.c
>>> @@ -371,6 +371,8 @@ static void handle_critical_trips(struct thermal_zone_device *tz,
>>>      if (tz->temperature < trip_temp)
>>>              return;
>>>
>>> +    trace_thermal_zone_trip(tz, trip, trip_type);
>>> +
>>>      if (tz->ops->notify)
>>>              tz->ops->notify(tz, trip, trip_type);
>>>
>>
>> Cheers,
>> Javi
>>
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>> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
>> the body of a message to majordomo@vger.kernel.org
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diff mbox

Patch

diff --git a/drivers/thermal/fair_share.c b/drivers/thermal/fair_share.c
index 2cddd68..6e0a3fb 100644
--- a/drivers/thermal/fair_share.c
+++ b/drivers/thermal/fair_share.c
@@ -42,12 +42,19 @@  static int get_trip_level(struct thermal_zone_device *tz)
 
 	for (count = 0; count < tz->trips; count++) {
 		tz->ops->get_trip_temp(tz, count, &trip_temp);
-		if (tz->temperature < trip_temp) {
-			tz->ops->get_trip_type(tz, count, &trip_type);
-			trace_thermal_zone_trip(tz, count, trip_type);
+		if (tz->temperature < trip_temp)
 			break;
-		}
 	}
+
+	/*
+	 * count > 0 only if temperature is greater than first trip
+	 * point, in which case, trip_point = count - 1
+	 */
+	if (count > 0) {
+		tz->ops->get_trip_type(tz, count - 1, &trip_type);
+		trace_thermal_zone_trip(tz, count - 1, trip_type);
+	}
+
 	return count;
 }