| Message ID | 20230710122138.1450930-4-james.clark@arm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | arm_pmu: Add PERF_PMU_CAP_EXTENDED_HW_TYPE capability | expand |
On Mon, Jul 10, 2023 at 5:22 AM James Clark <james.clark@arm.com> wrote: > > Since commit bd2756811766 ("perf: Rewrite core context handling") the > relationship between perf_event_context and PMUs has changed so that > the error scenario that PERF_PMU_CAP_HETEROGENEOUS_CPUS originally > silenced no longer exists. > > Remove the capability and associated comment to avoid confusion that it > actually influences any perf core behavior. This change should be a > no-op. > > Signed-off-by: James Clark <james.clark@arm.com> Acked-by: Ian Rogers <irogers@google.com> Thanks, Ian > --- > drivers/perf/arm_pmu.c | 7 ++----- > 1 file changed, 2 insertions(+), 5 deletions(-) > > diff --git a/drivers/perf/arm_pmu.c b/drivers/perf/arm_pmu.c > index d8844a9461a2..297906df6628 100644 > --- a/drivers/perf/arm_pmu.c > +++ b/drivers/perf/arm_pmu.c > @@ -872,15 +872,12 @@ struct arm_pmu *armpmu_alloc(void) > .attr_groups = pmu->attr_groups, > /* > * This is a CPU PMU potentially in a heterogeneous > - * configuration (e.g. big.LITTLE). This is not an uncore PMU, > - * and we have taken ctx sharing into account (e.g. with our > - * pmu::filter callback and pmu::event_init group validation). > - * > + * configuration (e.g. big.LITTLE) so > * PERF_PMU_CAP_EXTENDED_HW_TYPE is required to open the legacy > * PERF_TYPE_HARDWARE and PERF_TYPE_HW_CACHE events on a > * specific PMU. > */ > - .capabilities = PERF_PMU_CAP_HETEROGENEOUS_CPUS | PERF_PMU_CAP_EXTENDED_REGS | > + .capabilities = PERF_PMU_CAP_EXTENDED_REGS | > PERF_PMU_CAP_EXTENDED_HW_TYPE, > }; > > -- > 2.34.1 >
On 7/10/23 17:51, James Clark wrote: > Since commit bd2756811766 ("perf: Rewrite core context handling") the > relationship between perf_event_context and PMUs has changed so that > the error scenario that PERF_PMU_CAP_HETEROGENEOUS_CPUS originally > silenced no longer exists. > > Remove the capability and associated comment to avoid confusion that it > actually influences any perf core behavior. This change should be a > no-op. > > Signed-off-by: James Clark <james.clark@arm.com> > --- > drivers/perf/arm_pmu.c | 7 ++----- > 1 file changed, 2 insertions(+), 5 deletions(-) > > diff --git a/drivers/perf/arm_pmu.c b/drivers/perf/arm_pmu.c > index d8844a9461a2..297906df6628 100644 > --- a/drivers/perf/arm_pmu.c > +++ b/drivers/perf/arm_pmu.c > @@ -872,15 +872,12 @@ struct arm_pmu *armpmu_alloc(void) > .attr_groups = pmu->attr_groups, > /* > * This is a CPU PMU potentially in a heterogeneous > - * configuration (e.g. big.LITTLE). This is not an uncore PMU, > - * and we have taken ctx sharing into account (e.g. with our > - * pmu::filter callback and pmu::event_init group validation). > - * > + * configuration (e.g. big.LITTLE) so > * PERF_PMU_CAP_EXTENDED_HW_TYPE is required to open the legacy > * PERF_TYPE_HARDWARE and PERF_TYPE_HW_CACHE events on a > * specific PMU. > */ > - .capabilities = PERF_PMU_CAP_HETEROGENEOUS_CPUS | PERF_PMU_CAP_EXTENDED_REGS | > + .capabilities = PERF_PMU_CAP_EXTENDED_REGS | > PERF_PMU_CAP_EXTENDED_HW_TYPE, Small nit, the second line could be folded back into the first one. > }; >
On 11/07/2023 13:08, Anshuman Khandual wrote: > > > On 7/10/23 17:51, James Clark wrote: >> Since commit bd2756811766 ("perf: Rewrite core context handling") the >> relationship between perf_event_context and PMUs has changed so that >> the error scenario that PERF_PMU_CAP_HETEROGENEOUS_CPUS originally >> silenced no longer exists. >> >> Remove the capability and associated comment to avoid confusion that it >> actually influences any perf core behavior. This change should be a >> no-op. >> >> Signed-off-by: James Clark <james.clark@arm.com> >> --- >> drivers/perf/arm_pmu.c | 7 ++----- >> 1 file changed, 2 insertions(+), 5 deletions(-) >> >> diff --git a/drivers/perf/arm_pmu.c b/drivers/perf/arm_pmu.c >> index d8844a9461a2..297906df6628 100644 >> --- a/drivers/perf/arm_pmu.c >> +++ b/drivers/perf/arm_pmu.c >> @@ -872,15 +872,12 @@ struct arm_pmu *armpmu_alloc(void) >> .attr_groups = pmu->attr_groups, >> /* >> * This is a CPU PMU potentially in a heterogeneous >> - * configuration (e.g. big.LITTLE). This is not an uncore PMU, >> - * and we have taken ctx sharing into account (e.g. with our >> - * pmu::filter callback and pmu::event_init group validation). >> - * >> + * configuration (e.g. big.LITTLE) so >> * PERF_PMU_CAP_EXTENDED_HW_TYPE is required to open the legacy >> * PERF_TYPE_HARDWARE and PERF_TYPE_HW_CACHE events on a >> * specific PMU. >> */ >> - .capabilities = PERF_PMU_CAP_HETEROGENEOUS_CPUS | PERF_PMU_CAP_EXTENDED_REGS | >> + .capabilities = PERF_PMU_CAP_EXTENDED_REGS | >> PERF_PMU_CAP_EXTENDED_HW_TYPE, > > Small nit, the second line could be folded back into the first one. .clang-format has a column limit of 80 which is why it gets folded. The kernel coding style guide also still says 80 is a strongly preferred limit so I'll probably leave it. > >> }; >>
diff --git a/drivers/perf/arm_pmu.c b/drivers/perf/arm_pmu.c index d8844a9461a2..297906df6628 100644 --- a/drivers/perf/arm_pmu.c +++ b/drivers/perf/arm_pmu.c @@ -872,15 +872,12 @@ struct arm_pmu *armpmu_alloc(void) .attr_groups = pmu->attr_groups, /* * This is a CPU PMU potentially in a heterogeneous - * configuration (e.g. big.LITTLE). This is not an uncore PMU, - * and we have taken ctx sharing into account (e.g. with our - * pmu::filter callback and pmu::event_init group validation). - * + * configuration (e.g. big.LITTLE) so * PERF_PMU_CAP_EXTENDED_HW_TYPE is required to open the legacy * PERF_TYPE_HARDWARE and PERF_TYPE_HW_CACHE events on a * specific PMU. */ - .capabilities = PERF_PMU_CAP_HETEROGENEOUS_CPUS | PERF_PMU_CAP_EXTENDED_REGS | + .capabilities = PERF_PMU_CAP_EXTENDED_REGS | PERF_PMU_CAP_EXTENDED_HW_TYPE, };
Since commit bd2756811766 ("perf: Rewrite core context handling") the relationship between perf_event_context and PMUs has changed so that the error scenario that PERF_PMU_CAP_HETEROGENEOUS_CPUS originally silenced no longer exists. Remove the capability and associated comment to avoid confusion that it actually influences any perf core behavior. This change should be a no-op. Signed-off-by: James Clark <james.clark@arm.com> --- drivers/perf/arm_pmu.c | 7 ++----- 1 file changed, 2 insertions(+), 5 deletions(-)