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perf tools: Check if mem_events is supported for hybrid platform

Check if the mem_events ('mem-loads' and 'mem-stores') exist
in the sysfs path.

For Alderlake, the hybrid cpu pmu are "cpu_core" and "cpu_atom".
Check the existing of following paths:

/sys/devices/cpu_atom/events/mem-loads
/sys/devices/cpu_atom/events/mem-stores
/sys/devices/cpu_core/events/mem-loads
/sys/devices/cpu_core/events/mem-stores

If the patch exists, the mem_event is supported.

Signed-off-by: Jin Yao <yao.jin@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20210527001610.10553-5-yao.jin@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This commit is contained in:
Jin Yao 2021-05-27 08:16:06 +08:00 committed by Arnaldo Carvalho de Melo
parent a91ffcf30e
commit e7ce8d11bf

View File

@ -12,6 +12,8 @@
#include "mem-events.h"
#include "debug.h"
#include "symbol.h"
#include "pmu.h"
#include "pmu-hybrid.h"
unsigned int perf_mem_events__loads_ldlat = 30;
@ -100,6 +102,15 @@ int perf_mem_events__parse(const char *str)
return -1;
}
static bool perf_mem_event__supported(const char *mnt, char *sysfs_name)
{
char path[PATH_MAX];
struct stat st;
scnprintf(path, PATH_MAX, "%s/devices/%s", mnt, sysfs_name);
return !stat(path, &st);
}
int perf_mem_events__init(void)
{
const char *mnt = sysfs__mount();
@ -110,9 +121,9 @@ int perf_mem_events__init(void)
return -ENOENT;
for (j = 0; j < PERF_MEM_EVENTS__MAX; j++) {
char path[PATH_MAX];
struct perf_mem_event *e = perf_mem_events__ptr(j);
struct stat st;
struct perf_pmu *pmu;
char sysfs_name[100];
/*
* If the event entry isn't valid, skip initialization
@ -121,11 +132,20 @@ int perf_mem_events__init(void)
if (!e->tag)
continue;
scnprintf(path, PATH_MAX, "%s/devices/%s",
mnt, e->sysfs_name);
if (!perf_pmu__has_hybrid()) {
scnprintf(sysfs_name, sizeof(sysfs_name),
e->sysfs_name, "cpu");
e->supported = perf_mem_event__supported(mnt, sysfs_name);
} else {
perf_pmu__for_each_hybrid_pmu(pmu) {
scnprintf(sysfs_name, sizeof(sysfs_name),
e->sysfs_name, pmu->name);
e->supported |= perf_mem_event__supported(mnt, sysfs_name);
}
}
if (!stat(path, &st))
e->supported = found = true;
if (e->supported)
found = true;
}
return found ? 0 : -ENOENT;