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s390/cpumf: Handle events cycles and instructions identical

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[ Upstream commit be857b7f77d130dbbd47c91fc35198b040f35865 ]

Events CPU_CYCLES and INSTRUCTIONS can be submitted with two different
perf_event attribute::type values:
 - PERF_TYPE_HARDWARE: when invoked via perf tool predefined events name
   cycles or cpu-cycles or instructions.
 - pmu->type: when invoked via perf tool event name cpu_cf/CPU_CYLCES/ or
   cpu_cf/INSTRUCTIONS/. This invocation also selects the PMU to which
   the event belongs.
Handle both type of invocations identical for events CPU_CYLCES and
INSTRUCTIONS. They address the same hardware.
The result is different when event modifier exclude_kernel is also set.
Invocation with event modifier for user space event counting fails.

Output before:

 # perf stat -e cpum_cf/cpu_cycles/u -- true

 Performance counter stats for 'true':

   <not supported>      cpum_cf/cpu_cycles/u

       0.000761033 seconds time elapsed

       0.000076000 seconds user
       0.000725000 seconds sys

 #

Output after:
 # perf stat -e cpum_cf/cpu_cycles/u -- true

 Performance counter stats for 'true':

           349,613      cpum_cf/cpu_cycles/u

       0.000844143 seconds time elapsed

       0.000079000 seconds user
       0.000800000 seconds sys
 #

Fixes: 6a82e23f45 ("s390/cpumf: Adjust registration of s390 PMU device drivers")
Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Acked-by: Sumanth Korikkar <sumanthk@linux.ibm.com>
[agordeev@linux.ibm.com corrected commit ID of Fixes commit]
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Thomas Richter 2022-06-10 15:19:00 +02:00 committed by Greg Kroah-Hartman
parent abe487a88a
commit 5ee016f612
1 changed files with 21 additions and 1 deletions
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22
arch/s390/kernel/perf_cpum_cf.c
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@ -292,6 +292,26 @@ static int __hw_perf_event_init(struct perf_event *event, unsigned int type)
return err;
}
/* Events CPU_CYLCES and INSTRUCTIONS can be submitted with two different
* attribute::type values:
* - PERF_TYPE_HARDWARE:
* - pmu->type:
* Handle both type of invocations identical. They address the same hardware.
* The result is different when event modifiers exclude_kernel and/or
* exclude_user are also set.
*/
static int cpumf_pmu_event_type(struct perf_event *event)
{
u64 ev = event->attr.config;
if (cpumf_generic_events_basic[PERF_COUNT_HW_CPU_CYCLES] == ev ||
cpumf_generic_events_basic[PERF_COUNT_HW_INSTRUCTIONS] == ev ||
cpumf_generic_events_user[PERF_COUNT_HW_CPU_CYCLES] == ev ||
cpumf_generic_events_user[PERF_COUNT_HW_INSTRUCTIONS] == ev)
return PERF_TYPE_HARDWARE;
return PERF_TYPE_RAW;
}
static int cpumf_pmu_event_init(struct perf_event *event)
{
unsigned int type = event->attr.type;
@ -301,7 +321,7 @@ static int cpumf_pmu_event_init(struct perf_event *event)
err = __hw_perf_event_init(event, type);
else if (event->pmu->type == type)
/* Registered as unknown PMU */
err = __hw_perf_event_init(event, PERF_TYPE_RAW);
err = __hw_perf_event_init(event, cpumf_pmu_event_type(event));
else
return -ENOENT;