[PATCH v3 1/9] perf mem: Search event name with more flexible path

Leo Yan
2020-10-28T06:39:13Z

Perf tool searches memory event name under the folder
'/sys/devices/cpu/events/', this leads to the limitation for selection
memory profiling event which must be under this folder. Thus it's
impossible to use any other event as memory event which is not under
this specific folder, e.g. Arm SPE hardware event is not located in
'/sys/devices/cpu/events/' so it cannot be enabled for memory profiling.

This patch changes to search folder from '/sys/devices/cpu/events/' to
'/sys/devices', so it give flexibility to find events which can be used
for memory profiling.

Signed-off-by: Leo Yan <leo.yan@linaro.org>
Acked-by: Jiri Olsa <jolsa@redhat.com>
---
tools/perf/util/mem-events.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/tools/perf/util/mem-events.c b/tools/perf/util/mem-events.c
index ea0af0bc4314..35c8d175a9d2 100644
--- a/tools/perf/util/mem-events.c
+++ b/tools/perf/util/mem-events.c
@@ -18,8 +18,8 @@ unsigned int perf_mem_events__loads_ldlat = 30;
#define E(t, n, s) { .tag = t, .name = n, .sysfs_name = s }

struct perf_mem_event perf_mem_events[PERF_MEM_EVENTS__MAX] = {
- E("ldlat-loads", "cpu/mem-loads,ldlat=%u/P", "mem-loads"),
- E("ldlat-stores", "cpu/mem-stores/P", "mem-stores"),
+ E("ldlat-loads", "cpu/mem-loads,ldlat=%u/P", "cpu/events/mem-loads"),
+ E("ldlat-stores", "cpu/mem-stores/P", "cpu/events/mem-stores"),
};
#undef E

@@ -93,7 +93,7 @@ int perf_mem_events__init(void)
struct perf_mem_event *e = &perf_mem_events[j];
struct stat st;

- scnprintf(path, PATH_MAX, "%s/devices/cpu/events/%s",
+ scnprintf(path, PATH_MAX, "%s/devices/%s",
mnt, e->sysfs_name);

if (!stat(path, &st))