[PATCH v2 3/3] perf mem: Scan all PMUs instead of just core ones

Ravi Bangoria
2023-06-15T05:18:33Z

Scanning only core PMUs is not sufficient on platforms like AMD since
perf mem on AMD uses IBS OP PMU, which is independent of core PMU.
Scan all PMUs instead of just core PMUs. There should be negligible
performance overhead because of scanning all PMUs, so we should be okay.

Signed-off-by: Ravi Bangoria <ravi.bangoria@amd.com>
---
tools/perf/util/mem-events.c | 13 +++++++++----
1 file changed, 9 insertions(+), 4 deletions(-)

diff --git a/tools/perf/util/mem-events.c b/tools/perf/util/mem-events.c
index be15aadb6b14..c07fe3a90722 100644
--- a/tools/perf/util/mem-events.c
+++ b/tools/perf/util/mem-events.c
@@ -130,7 +130,12 @@ int perf_mem_events__init(void)
if (!e->tag)
continue;

- while ((pmu = perf_pmus__scan_core(pmu)) != NULL) {
+ /*
+ * Scan all PMUs not just core ones, since perf mem/c2c on
+ * platforms like AMD uses IBS OP PMU which is independent
+ * of core PMU.
+ */
+ while ((pmu = perf_pmus__scan(pmu)) != NULL) {
scnprintf(sysfs_name, sizeof(sysfs_name), e->sysfs_name, pmu->name);
e->supported |= perf_mem_event__supported(mnt, sysfs_name);
}
@@ -165,7 +170,7 @@ static void perf_mem_events__print_unsupport_hybrid(struct perf_mem_event *e,
char sysfs_name[100];
struct perf_pmu *pmu = NULL;

- while ((pmu = perf_pmus__scan_core(pmu)) != NULL) {
+ while ((pmu = perf_pmus__scan(pmu)) != NULL) {
scnprintf(sysfs_name, sizeof(sysfs_name), e->sysfs_name,
pmu->name);
if (!perf_mem_event__supported(mnt, sysfs_name)) {
@@ -188,7 +193,7 @@ int perf_mem_events__record_args(const char **rec_argv, int *argv_nr,
if (!e->record)
continue;

- if (perf_pmus__num_core_pmus() == 1) {
+ if (perf_pmus__num_mem_pmus() == 1) {
if (!e->supported) {
pr_err("failed: event '%s' not supported\n",
perf_mem_events__name(j, NULL));
@@ -203,7 +208,7 @@ int perf_mem_events__record_args(const char **rec_argv, int *argv_nr,
return -1;
}

- while ((pmu = perf_pmus__scan_core(pmu)) != NULL) {
+ while ((pmu = perf_pmus__scan(pmu)) != NULL) {
rec_argv[i++] = "-e";
s = perf_mem_events__name(j, pmu->name);
if (s) {
--
2.40.1