[Fix up LKML address.]
On Thu, Mar 1, 2018 at 3:27 AM, Du, Changbin <changbin...@intel.com> wrote:
> On Wed, Feb 28, 2018 at 11:27:09AM +0100, Rafael J. Wysocki wrote:
>> On Wed, Feb 28, 2018 at 10:20 AM, <changbin...@intel.com> wrote:
>> > From: Changbin Du <changbin...@intel.com>
>> > The type of state is signed int, convert it to unsigned int looks weird.
>> > (-1 become 4294967295)
>> > 932.123 power:cpu_idle:state=1 cpu_id=0)
>> > 932.125 power:cpu_idle:state=4294967295 cpu_id=0)
>> > 932.132 power:cpu_idle:state=1 cpu_id=0)
>> > 932.133 power:cpu_idle:state=4294967295 cpu_id=0)
>> > Similarly for cpu_frequency as "state=%lu cpu_id=%lu". User need to read
>> > the code to understand what 'state' means.
>> > No functional change in this patch.
>> That rather isn't the case if negative values are ever passed to the
>> tracepoint, right?
>> Which seems to be the reason why you want to make this change, isn't it?
> yes, to improve readability.
>> So maybe fix the code using the tracepoint(s) to avoid passing
>> negative values to it(them)?
> For cpu_idle event, [0, CPUIDLE_STATE_MAX) are used to index the idle state
> so I think a appropriate value for PWR_EVENT_EXIT is -1 (defined in
> Or do you have a better idea? Thanks!
Sorry, I'm not sure what you mean.
I'm saying that the code using the CPU PM tracepoints is not expected
to pass -1 as the CPU number to them. IOW, neither -1 nor its UL
representation should ever appear in the output of these tracepoints.
If that happens, it is a problem with the code using the tracepoints
which needs to be fixed. Users should not see any of these values.