[PATCH v1 3/5] perf tools: Check if mem_events is supported for hybrid

[Jin Yao]

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@xxxxxxxxxxxxxxx>
---
 tools/perf/util/mem-events.c | 43 +++++++++++++++++++++++++++++-------
 1 file changed, 35 insertions(+), 8 deletions(-)

diff --git a/tools/perf/util/mem-events.c b/tools/perf/util/mem-events.c
index c736eaded06c..e8f6e745eaf0 100644
--- a/tools/perf/util/mem-events.c
+++ b/tools/perf/util/mem-events.c
@@ -12,14 +12,16 @@
 #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;
 
 #define E(t, n, s) { .tag = t, .name = n, .sysfs_name = s }
 
 static struct perf_mem_event perf_mem_events[PERF_MEM_EVENTS__MAX] = {
-	E("ldlat-loads",	"cpu/mem-loads,ldlat=%u/P",	"cpu/events/mem-loads"),
-	E("ldlat-stores",	"cpu/mem-stores/P",		"cpu/events/mem-stores"),
+	E("ldlat-loads",	"%s/mem-loads,ldlat=%u/P",	"%s/events/mem-loads"),
+	E("ldlat-stores",	"%s/mem-stores/P",		"%s/events/mem-stores"),
 	E(NULL,			NULL,				NULL),
 };
 #undef E
@@ -100,6 +102,18 @@ int perf_mem_events__parse(const char *str)
 	return -1;
 }
 
+static bool perf_mem_events__supported(const char *mnt, char *sysfs_name)
+{
+	char path[PATH_MAX];
+	struct stat st;
+
+	scnprintf(path, PATH_MAX, "%s/devices/%s", mnt, sysfs_name);
+	if (!stat(path, &st))
+		return true;
+
+	return false;
+}
+
 int perf_mem_events__init(void)
 {
 	const char *mnt = sysfs__mount();
@@ -110,9 +124,10 @@ 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];
+		int unsupported = 0;
 
 		/*
 		 * If the event entry isn't valid, skip initialization
@@ -121,11 +136,23 @@ 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_events__supported(mnt, sysfs_name);
+		} else {
+			perf_pmu__for_each_hybrid_pmu(pmu) {
+				scnprintf(sysfs_name, sizeof(sysfs_name),
+					  e->sysfs_name, pmu->name);
+				if (!perf_mem_events__supported(mnt, sysfs_name))
+					unsupported++;
+			}
+
+			e->supported = (unsupported == 0) ? true : false;
+		}
 
-		if (!stat(path, &st))
-			e->supported = found = true;
+		if (e->supported)
+			found = true;
 	}
 
 	return found ? 0 : -ENOENT;
-- 
2.17.1