[PATCH 2/3] perf mem: Fix missed p-core mem events on ADL and RPL

From: kan . liang
Date: Thu Sep 05 2024 - 13:07:30 EST


From: Kan Liang <kan.liang@xxxxxxxxxxxxxxx>

The p-core mem events are missed when launching perf mem record on ADL
and RPL.

root@number:~# perf mem record sleep 1
Memory events are enabled on a subset of CPUs: 16-27
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.032 MB perf.data ]
root@number:~# perf evlist
cpu_atom/mem-loads,ldlat=30/P
cpu_atom/mem-stores/P
dummy:u

A variable 'record' in the struct perf_mem_event is to indicate whether
a mem event in a mem_events[] should be recorded. The current code only
configure the variable for the first eligible PMU. It's good enough for
a non-hybrid machine or a hybrid machine which has the same
mem_events[]. However, if a different mem_events[] is used for different
PMUs on a hybrid machine, e.g., ADL or RPL, the 'record' for the second
PMU never get a chance to be set. The mem_events[] of the second PMU
are always ignored.

Perf mem doesn't support the per-PMU configuration now. A
per-PMU mem_events[] 'record' variable doesn't make sense. Make it
global. That could also avoid searching for the per-PMU mem_events[]
via perf_pmu__mem_events_ptr every time.

Fixes: abbdd79b786e ("perf mem: Clean up perf_mem_events__name()")
Reported-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
Closes: https://lore.kernel.org/lkml/Zthu81fA3kLC2CS2@x1/
Signed-off-by: Kan Liang <kan.liang@xxxxxxxxxxxxxxx>
---
tools/perf/builtin-c2c.c | 12 ++++--------
tools/perf/builtin-mem.c | 17 ++++++-----------
tools/perf/util/mem-events.c | 6 ++++--
tools/perf/util/mem-events.h | 2 +-
4 files changed, 15 insertions(+), 22 deletions(-)

diff --git a/tools/perf/builtin-c2c.c b/tools/perf/builtin-c2c.c
index cef95b2781c0..15e1fce71c72 100644
--- a/tools/perf/builtin-c2c.c
+++ b/tools/perf/builtin-c2c.c
@@ -3285,19 +3285,15 @@ static int perf_c2c__record(int argc, const char **argv)
* PERF_MEM_EVENTS__LOAD_STORE if it is supported.
*/
if (e->tag) {
- e->record = true;
+ perf_mem_record[PERF_MEM_EVENTS__LOAD_STORE] = true;
rec_argv[i++] = "-W";
} else {
- e = perf_pmu__mem_events_ptr(pmu, PERF_MEM_EVENTS__LOAD);
- e->record = true;
-
- e = perf_pmu__mem_events_ptr(pmu, PERF_MEM_EVENTS__STORE);
- e->record = true;
+ perf_mem_record[PERF_MEM_EVENTS__LOAD] = true;
+ perf_mem_record[PERF_MEM_EVENTS__STORE] = true;
}
}

- e = perf_pmu__mem_events_ptr(pmu, PERF_MEM_EVENTS__LOAD);
- if (e->record)
+ if (perf_mem_record[PERF_MEM_EVENTS__LOAD])
rec_argv[i++] = "-W";

rec_argv[i++] = "-d";
diff --git a/tools/perf/builtin-mem.c b/tools/perf/builtin-mem.c
index f6be7ffc9e45..ba1d37bfb916 100644
--- a/tools/perf/builtin-mem.c
+++ b/tools/perf/builtin-mem.c
@@ -117,22 +117,17 @@ static int __cmd_record(int argc, const char **argv, struct perf_mem *mem,
if (e->tag &&
(mem->operation & MEM_OPERATION_LOAD) &&
(mem->operation & MEM_OPERATION_STORE)) {
- e->record = true;
+ perf_mem_record[PERF_MEM_EVENTS__LOAD_STORE] = true;
rec_argv[i++] = "-W";
} else {
- if (mem->operation & MEM_OPERATION_LOAD) {
- e = perf_pmu__mem_events_ptr(pmu, PERF_MEM_EVENTS__LOAD);
- e->record = true;
- }
+ if (mem->operation & MEM_OPERATION_LOAD)
+ perf_mem_record[PERF_MEM_EVENTS__LOAD] = true;

- if (mem->operation & MEM_OPERATION_STORE) {
- e = perf_pmu__mem_events_ptr(pmu, PERF_MEM_EVENTS__STORE);
- e->record = true;
- }
+ if (mem->operation & MEM_OPERATION_STORE)
+ perf_mem_record[PERF_MEM_EVENTS__STORE] = true;
}

- e = perf_pmu__mem_events_ptr(pmu, PERF_MEM_EVENTS__LOAD);
- if (e->record)
+ if (perf_mem_record[PERF_MEM_EVENTS__LOAD])
rec_argv[i++] = "-W";

rec_argv[i++] = "-d";
diff --git a/tools/perf/util/mem-events.c b/tools/perf/util/mem-events.c
index 17f80013e574..051feb93ed8d 100644
--- a/tools/perf/util/mem-events.c
+++ b/tools/perf/util/mem-events.c
@@ -29,6 +29,8 @@ struct perf_mem_event perf_mem_events[PERF_MEM_EVENTS__MAX] = {
};
#undef E

+bool perf_mem_record[PERF_MEM_EVENTS__MAX] = { 0 };
+
static char mem_loads_name[100];
static char mem_stores_name[100];

@@ -163,7 +165,7 @@ int perf_pmu__mem_events_parse(struct perf_pmu *pmu, const char *str)
continue;

if (strstr(e->tag, tok))
- e->record = found = true;
+ perf_mem_record[j] = found = true;
}

tok = strtok_r(NULL, ",", &saveptr);
@@ -261,7 +263,7 @@ int perf_mem_events__record_args(const char **rec_argv, int *argv_nr)
for (int j = 0; j < PERF_MEM_EVENTS__MAX; j++) {
e = perf_pmu__mem_events_ptr(pmu, j);

- if (!e->record)
+ if (!perf_mem_record[j])
continue;

if (!e->supported) {
diff --git a/tools/perf/util/mem-events.h b/tools/perf/util/mem-events.h
index a6fc2a593938..8dc27db9fd52 100644
--- a/tools/perf/util/mem-events.h
+++ b/tools/perf/util/mem-events.h
@@ -6,7 +6,6 @@
#include <linux/types.h>

struct perf_mem_event {
- bool record;
bool supported;
bool ldlat;
u32 aux_event;
@@ -28,6 +27,7 @@ struct perf_pmu;

extern unsigned int perf_mem_events__loads_ldlat;
extern struct perf_mem_event perf_mem_events[PERF_MEM_EVENTS__MAX];
+extern bool perf_mem_record[PERF_MEM_EVENTS__MAX];

int perf_pmu__mem_events_parse(struct perf_pmu *pmu, const char *str);
int perf_pmu__mem_events_init(void);
--
2.38.1