summaryrefslogtreecommitdiff
path: root/tools/perf/arch/arm/util/pmu.c
diff options
context:
space:
mode:
authorIan Rogers <irogers@google.com>2023-10-12 20:56:45 +0300
committerNamhyung Kim <namhyung@kernel.org>2023-10-17 22:40:50 +0300
commit0197da7affab502cd6e25da616ad038b169a7a77 (patch)
tree4d6ee74bb61b24c72399d2e533de338a9fc64f37 /tools/perf/arch/arm/util/pmu.c
parentf20c15d13f017d4b46523990a0f3ba42025391a6 (diff)
downloadlinux-0197da7affab502cd6e25da616ad038b169a7a77.tar.xz
perf pmu: Lazily compute default config
The default config is computed during creation of the PMU and may do things like scanning sysfs, when the PMU may just be used as part of scanning. Change default_config to perf_event_attr_init_default, a callback that is used when a default config needs initializing. This avoids holding onto the memory for a perf_event_attr and copying. On a tigerlake laptop running the pmu-scan benchmark: Before: Running 'internals/pmu-scan' benchmark: Computing performance of sysfs PMU event scan for 100 times Average core PMU scanning took: 28.780 usec (+- 0.503 usec) Average PMU scanning took: 283.480 usec (+- 18.471 usec) Number of openat syscalls: 30,227 After: Running 'internals/pmu-scan' benchmark: Computing performance of sysfs PMU event scan for 100 times Average core PMU scanning took: 27.880 usec (+- 0.169 usec) Average PMU scanning took: 245.260 usec (+- 15.758 usec) Number of openat syscalls: 28,914 Over 3 runs it is a nearly 12% reduction in execution time and a 4.3% of openat calls. Signed-off-by: Ian Rogers <irogers@google.com> Reviewed-by: Adrian Hunter <adrian.hunter@intel.com> Cc: Ravi Bangoria <ravi.bangoria@amd.com> Cc: James Clark <james.clark@arm.com> Cc: Suzuki K Poulose <suzuki.poulose@arm.com> Cc: Yang Jihong <yangjihong1@huawei.com> Cc: Will Deacon <will@kernel.org> Cc: Leo Yan <leo.yan@linaro.org> Cc: Mike Leach <mike.leach@linaro.org> Cc: Jing Zhang <renyu.zj@linux.alibaba.com> Cc: Kajol Jain <kjain@linux.ibm.com> Cc: Thomas Richter <tmricht@linux.ibm.com> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: John Garry <john.g.garry@oracle.com> Cc: linux-arm-kernel@lists.infradead.org Cc: coresight@lists.linaro.org Link: https://lore.kernel.org/r/20231012175645.1849503-8-irogers@google.com Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Diffstat (limited to 'tools/perf/arch/arm/util/pmu.c')
-rw-r--r--tools/perf/arch/arm/util/pmu.c4
1 files changed, 2 insertions, 2 deletions
diff --git a/tools/perf/arch/arm/util/pmu.c b/tools/perf/arch/arm/util/pmu.c
index f25f68f84a94..7f3af3b97f3b 100644
--- a/tools/perf/arch/arm/util/pmu.c
+++ b/tools/perf/arch/arm/util/pmu.c
@@ -20,12 +20,12 @@ void perf_pmu__arch_init(struct perf_pmu *pmu __maybe_unused)
if (!strcmp(pmu->name, CORESIGHT_ETM_PMU_NAME)) {
/* add ETM default config here */
pmu->selectable = true;
- pmu->default_config = cs_etm_get_default_config(pmu);
+ pmu->perf_event_attr_init_default = cs_etm_get_default_config;
#if defined(__aarch64__)
} else if (strstarts(pmu->name, ARM_SPE_PMU_NAME)) {
pmu->selectable = true;
pmu->is_uncore = false;
- pmu->default_config = arm_spe_pmu_default_config(pmu);
+ pmu->perf_event_attr_init_default = arm_spe_pmu_default_config;
} else if (strstarts(pmu->name, HISI_PTT_PMU_NAME)) {
pmu->selectable = true;
#endif