Several fixes for group flag and counters-snapshotting

[PATCH V2 0/5] Several fixes for group flag and counters-snapshotting

Posted by kan.liang@linux.intel.com 9 months, 2 weeks ago

From: Kan Liang <kan.liang@linux.intel.com>

The patch series includes several fixes for the new Intel features.

The first 4 patches are to fix the group flag issue which impacts the
branch counters, PEBS counters-snapshotting and ACR.
The V1 can be found at
https://lore.kernel.org/lkml/20250423221015.268949-1-kan.liang@linux.intel.com/

The last patch is to fix an issue of counters-snapshotting.
The V1 can be found at
https://lore.kernel.org/lkml/20250204210514.4089680-1-kan.liang@linux.intel.com/

Kan Liang (5):
  perf/x86/intel: Only check the group flag for X86 leader
  perf/x86/intel: Check the X86 leader for pebs_counter_event_group
  perf/x86/intel: Check the X86 leader for ACR group
  perf/x86: Optimize the is_x86_event
  perf/x86/intel/ds: Fix counter backwards of non-precise events
    counters-snapshotting

 arch/x86/events/core.c       | 19 ++++++++++---------
 arch/x86/events/intel/ds.c   | 21 +++++++++++++++++++--
 arch/x86/events/perf_event.h | 14 ++++++++++----
 3 files changed, 39 insertions(+), 15 deletions(-)

-- 
2.38.1

Re: [PATCH V2 0/5] Several fixes for group flag and counters-snapshotting

Posted by Peter Zijlstra 9 months, 2 weeks ago

On Thu, Apr 24, 2025 at 06:47:13AM -0700, kan.liang@linux.intel.com wrote:
> From: Kan Liang <kan.liang@linux.intel.com>
> 
> The patch series includes several fixes for the new Intel features.
> 
> The first 4 patches are to fix the group flag issue which impacts the
> branch counters, PEBS counters-snapshotting and ACR.
> The V1 can be found at
> https://lore.kernel.org/lkml/20250423221015.268949-1-kan.liang@linux.intel.com/
> 
> The last patch is to fix an issue of counters-snapshotting.
> The V1 can be found at
> https://lore.kernel.org/lkml/20250204210514.4089680-1-kan.liang@linux.intel.com/
> 
> Kan Liang (5):
>   perf/x86/intel: Only check the group flag for X86 leader
>   perf/x86/intel: Check the X86 leader for pebs_counter_event_group
>   perf/x86/intel: Check the X86 leader for ACR group
>   perf/x86: Optimize the is_x86_event
>   perf/x86/intel/ds: Fix counter backwards of non-precise events
>     counters-snapshotting

It didn't apply cleanly, but I stomped on it and pushed out new
perf/urgent and perf/core branches that contain these patches. Hopefully
I didn't mess it up ;-)

Re: [PATCH V2 0/5] Several fixes for group flag and counters-snapshotting

Posted by Liang, Kan 9 months, 2 weeks ago


On 2025-04-24 10:25 a.m., Peter Zijlstra wrote:
> On Thu, Apr 24, 2025 at 06:47:13AM -0700, kan.liang@linux.intel.com wrote:
>> From: Kan Liang <kan.liang@linux.intel.com>
>>
>> The patch series includes several fixes for the new Intel features.
>>
>> The first 4 patches are to fix the group flag issue which impacts the
>> branch counters, PEBS counters-snapshotting and ACR.
>> The V1 can be found at
>> https://lore.kernel.org/lkml/20250423221015.268949-1-kan.liang@linux.intel.com/
>>
>> The last patch is to fix an issue of counters-snapshotting.
>> The V1 can be found at
>> https://lore.kernel.org/lkml/20250204210514.4089680-1-kan.liang@linux.intel.com/
>>
>> Kan Liang (5):
>>   perf/x86/intel: Only check the group flag for X86 leader
>>   perf/x86/intel: Check the X86 leader for pebs_counter_event_group
>>   perf/x86/intel: Check the X86 leader for ACR group
>>   perf/x86: Optimize the is_x86_event
>>   perf/x86/intel/ds: Fix counter backwards of non-precise events
>>     counters-snapshotting
> 
> It didn't apply cleanly,

Sorry for it.

> but I stomped on it and pushed out new
> perf/urgent and perf/core branches that contain these patches. Hopefully
> I didn't mess it up ;-)

Something is missed in this patch 5d4d71ebc737 ("perf/x86/intel: Only
check the group flag for X86 leader")

diff --git a/arch/x86/events/perf_event.h b/arch/x86/events/perf_event.h
index a73b1ff031b2..1f72a4f77b5c 100644
--- a/arch/x86/events/perf_event.h
+++ b/arch/x86/events/perf_event.h
@@ -119,7 +119,7 @@ static inline bool check_leader_group(struct
perf_event *leader, int flags)

 static inline bool is_branch_counters_group(struct perf_event *event)
 {
-	return check_leader_group(event->group_leader, PERF_X86_EVENT_PEBS_CNTR);
+	return check_leader_group(event->group_leader,
PERF_X86_EVENT_BRANCH_COUNTERS);
 }

 static inline bool is_pebs_counter_event_group(struct perf_event *event)
@@ -1123,7 +1123,6 @@ static struct perf_pmu_format_hybrid_attr
format_attr_hybrid_##_name = {\
 	.pmu_type	= _pmu,                                         \
 }

-int is_x86_event(struct perf_event *event);
 struct pmu *x86_get_pmu(unsigned int cpu);
 extern struct x86_pmu x86_pmu __read_mostly;


Thanks,
Kan

Re: [PATCH V2 0/5] Several fixes for group flag and counters-snapshotting

Posted by Peter Zijlstra 9 months, 2 weeks ago

On Thu, Apr 24, 2025 at 12:00:02PM -0400, Liang, Kan wrote:
> 
> 
> On 2025-04-24 10:25 a.m., Peter Zijlstra wrote:
> > On Thu, Apr 24, 2025 at 06:47:13AM -0700, kan.liang@linux.intel.com wrote:
> >> From: Kan Liang <kan.liang@linux.intel.com>
> >>
> >> The patch series includes several fixes for the new Intel features.
> >>
> >> The first 4 patches are to fix the group flag issue which impacts the
> >> branch counters, PEBS counters-snapshotting and ACR.
> >> The V1 can be found at
> >> https://lore.kernel.org/lkml/20250423221015.268949-1-kan.liang@linux.intel.com/
> >>
> >> The last patch is to fix an issue of counters-snapshotting.
> >> The V1 can be found at
> >> https://lore.kernel.org/lkml/20250204210514.4089680-1-kan.liang@linux.intel.com/
> >>
> >> Kan Liang (5):
> >>   perf/x86/intel: Only check the group flag for X86 leader
> >>   perf/x86/intel: Check the X86 leader for pebs_counter_event_group
> >>   perf/x86/intel: Check the X86 leader for ACR group
> >>   perf/x86: Optimize the is_x86_event
> >>   perf/x86/intel/ds: Fix counter backwards of non-precise events
> >>     counters-snapshotting
> > 
> > It didn't apply cleanly,
> 
> Sorry for it.
> 
> > but I stomped on it and pushed out new
> > perf/urgent and perf/core branches that contain these patches. Hopefully
> > I didn't mess it up ;-)
> 
> Something is missed in this patch 5d4d71ebc737 ("perf/x86/intel: Only
> check the group flag for X86 leader")
> 
> diff --git a/arch/x86/events/perf_event.h b/arch/x86/events/perf_event.h
> index a73b1ff031b2..1f72a4f77b5c 100644
> --- a/arch/x86/events/perf_event.h
> +++ b/arch/x86/events/perf_event.h
> @@ -119,7 +119,7 @@ static inline bool check_leader_group(struct
> perf_event *leader, int flags)
> 
>  static inline bool is_branch_counters_group(struct perf_event *event)
>  {
> -	return check_leader_group(event->group_leader, PERF_X86_EVENT_PEBS_CNTR);
> +	return check_leader_group(event->group_leader,
> PERF_X86_EVENT_BRANCH_COUNTERS);
>  }
> 
>  static inline bool is_pebs_counter_event_group(struct perf_event *event)

Right.

> @@ -1123,7 +1123,6 @@ static struct perf_pmu_format_hybrid_attr
> format_attr_hybrid_##_name = {\
>  	.pmu_type	= _pmu,                                         \
>  }
> 
> -int is_x86_event(struct perf_event *event);
>  struct pmu *x86_get_pmu(unsigned int cpu);
>  extern struct x86_pmu x86_pmu __read_mostly;

See, that isn't there in tip/perf/urgent :-)


I've pushed out an updated set. Please check.

Re: [PATCH V2 0/5] Several fixes for group flag and counters-snapshotting

Posted by Liang, Kan 9 months, 2 weeks ago


On 2025-04-25 8:55 a.m., Peter Zijlstra wrote:
> On Thu, Apr 24, 2025 at 12:00:02PM -0400, Liang, Kan wrote:
>>
>>
>> On 2025-04-24 10:25 a.m., Peter Zijlstra wrote:
>>> On Thu, Apr 24, 2025 at 06:47:13AM -0700, kan.liang@linux.intel.com wrote:
>>>> From: Kan Liang <kan.liang@linux.intel.com>
>>>>
>>>> The patch series includes several fixes for the new Intel features.
>>>>
>>>> The first 4 patches are to fix the group flag issue which impacts the
>>>> branch counters, PEBS counters-snapshotting and ACR.
>>>> The V1 can be found at
>>>> https://lore.kernel.org/lkml/20250423221015.268949-1-kan.liang@linux.intel.com/
>>>>
>>>> The last patch is to fix an issue of counters-snapshotting.
>>>> The V1 can be found at
>>>> https://lore.kernel.org/lkml/20250204210514.4089680-1-kan.liang@linux.intel.com/
>>>>
>>>> Kan Liang (5):
>>>>   perf/x86/intel: Only check the group flag for X86 leader
>>>>   perf/x86/intel: Check the X86 leader for pebs_counter_event_group
>>>>   perf/x86/intel: Check the X86 leader for ACR group
>>>>   perf/x86: Optimize the is_x86_event
>>>>   perf/x86/intel/ds: Fix counter backwards of non-precise events
>>>>     counters-snapshotting
>>>
>>> It didn't apply cleanly,
>>
>> Sorry for it.
>>
>>> but I stomped on it and pushed out new
>>> perf/urgent and perf/core branches that contain these patches. Hopefully
>>> I didn't mess it up ;-)
>>
>> Something is missed in this patch 5d4d71ebc737 ("perf/x86/intel: Only
>> check the group flag for X86 leader")
>>
>> diff --git a/arch/x86/events/perf_event.h b/arch/x86/events/perf_event.h
>> index a73b1ff031b2..1f72a4f77b5c 100644
>> --- a/arch/x86/events/perf_event.h
>> +++ b/arch/x86/events/perf_event.h
>> @@ -119,7 +119,7 @@ static inline bool check_leader_group(struct
>> perf_event *leader, int flags)
>>
>>  static inline bool is_branch_counters_group(struct perf_event *event)
>>  {
>> -	return check_leader_group(event->group_leader, PERF_X86_EVENT_PEBS_CNTR);
>> +	return check_leader_group(event->group_leader,
>> PERF_X86_EVENT_BRANCH_COUNTERS);
>>  }
>>
>>  static inline bool is_pebs_counter_event_group(struct perf_event *event)
> 
> Right.
> 
>> @@ -1123,7 +1123,6 @@ static struct perf_pmu_format_hybrid_attr
>> format_attr_hybrid_##_name = {\
>>  	.pmu_type	= _pmu,                                         \
>>  }
>>
>> -int is_x86_event(struct perf_event *event);
>>  struct pmu *x86_get_pmu(unsigned int cpu);
>>  extern struct x86_pmu x86_pmu __read_mostly;
> 
> See, that isn't there in tip/perf/urgent :-)
> >
> I've pushed out an updated set. Please check.

It looks good to me. Thanks a lot! :)

Kan