[PATCH v2 2/2] perf parse-events: Remove "not supported" hybrid cache events
From: zhengjun . xing
Date: Thu Sep 22 2022 - 22:58:56 EST
From: Zhengjun Xing <zhengjun.xing@xxxxxxxxxxxxxxx>
By default, we create two hybrid cache events, one is for cpu_core, and
another is for cpu_atom. But Some hybrid hardware cache events are only
available on one CPU PMU. For example, the 'L1-dcache-load-misses' is only
available on cpu_core, while the 'L1-icache-loads' is only available on
cpu_atom. We need to remove "not supported" hybrid cache events. By
extending is_event_supported() to global API and using it to check if the
hybrid cache events are supported before being created, we can remove the
"not supported" hybrid cache events.
Before:
# ./perf stat -e L1-dcache-load-misses,L1-icache-loads -a sleep 1
Performance counter stats for 'system wide':
52,570 cpu_core/L1-dcache-load-misses/
<not supported> cpu_atom/L1-dcache-load-misses/
<not supported> cpu_core/L1-icache-loads/
1,471,817 cpu_atom/L1-icache-loads/
1.004915229 seconds time elapsed
After:
# ./perf stat -e L1-dcache-load-misses,L1-icache-loads -a sleep 1
Performance counter stats for 'system wide':
54,510 cpu_core/L1-dcache-load-misses/
1,441,286 cpu_atom/L1-icache-loads/
1.005114281 seconds time elapsed
Fixes: 30def61f64ba ("perf parse-events: Create two hybrid cache events")
Signed-off-by: Zhengjun Xing <zhengjun.xing@xxxxxxxxxxxxxxx>
Reviewed-by: Kan Liang <kan.liang@xxxxxxxxxxxxxxx>
Reported-by: Yi Ammy <ammy.yi@xxxxxxxxx>
---
Change log:
v2:
* Adds a comment for removing "not supported" hybrid cache events.
* Remove goto and add a strdup check
* "is_event_supported" move to parse-events.c per Ian's suggestion.
* Adds Reported-by from Yi Ammy <ammy.yi@xxxxxxxxx>
tools/perf/util/parse-events-hybrid.c | 21 ++++++++++++---
tools/perf/util/parse-events.c | 39 +++++++++++++++++++++++++++
tools/perf/util/parse-events.h | 1 +
tools/perf/util/print-events.c | 39 ---------------------------
4 files changed, 57 insertions(+), 43 deletions(-)
diff --git a/tools/perf/util/parse-events-hybrid.c b/tools/perf/util/parse-events-hybrid.c
index 284f8eabd3b9..7c9f9150bad5 100644
--- a/tools/perf/util/parse-events-hybrid.c
+++ b/tools/perf/util/parse-events-hybrid.c
@@ -33,7 +33,8 @@ static void config_hybrid_attr(struct perf_event_attr *attr,
* If the PMU type ID is 0, the PERF_TYPE_RAW will be applied.
*/
attr->type = type;
- attr->config = attr->config | ((__u64)pmu_type << PERF_PMU_TYPE_SHIFT);
+ attr->config = (attr->config & PERF_HW_EVENT_MASK) |
+ ((__u64)pmu_type << PERF_PMU_TYPE_SHIFT);
}
static int create_event_hybrid(__u32 config_type, int *idx,
@@ -48,13 +49,25 @@ static int create_event_hybrid(__u32 config_type, int *idx,
__u64 config = attr->config;
config_hybrid_attr(attr, config_type, pmu->type);
+
+ /*
+ * Some hybrid hardware cache events are only available on one CPU
+ * PMU. For example, the 'L1-dcache-load-misses' is only available
+ * on cpu_core, while the 'L1-icache-loads' is only available on
+ * cpu_atom. We need to remove "not supported" hybrid cache events.
+ */
+ if (attr->type == PERF_TYPE_HW_CACHE
+ && !is_event_supported(attr->type, attr->config))
+ return 0;
+
evsel = parse_events__add_event_hybrid(list, idx, attr, name, metric_id,
pmu, config_terms);
- if (evsel)
+ if (evsel) {
evsel->pmu_name = strdup(pmu->name);
- else
+ if (!evsel->pmu_name)
+ return -ENOMEM;
+ } else
return -ENOMEM;
-
attr->type = type;
attr->config = config;
return 0;
diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c
index f05e15acd33f..f3b2c2a87456 100644
--- a/tools/perf/util/parse-events.c
+++ b/tools/perf/util/parse-events.c
@@ -28,6 +28,7 @@
#include "util/parse-events-hybrid.h"
#include "util/pmu-hybrid.h"
#include "tracepoint.h"
+#include "thread_map.h"
#define MAX_NAME_LEN 100
@@ -157,6 +158,44 @@ struct event_symbol event_symbols_sw[PERF_COUNT_SW_MAX] = {
#define PERF_EVENT_TYPE(config) __PERF_EVENT_FIELD(config, TYPE)
#define PERF_EVENT_ID(config) __PERF_EVENT_FIELD(config, EVENT)
+bool is_event_supported(u8 type, u64 config)
+{
+ bool ret = true;
+ int open_return;
+ struct evsel *evsel;
+ struct perf_event_attr attr = {
+ .type = type,
+ .config = config,
+ .disabled = 1,
+ };
+ struct perf_thread_map *tmap = thread_map__new_by_tid(0);
+
+ if (tmap == NULL)
+ return false;
+
+ evsel = evsel__new(&attr);
+ if (evsel) {
+ open_return = evsel__open(evsel, NULL, tmap);
+ ret = open_return >= 0;
+
+ if (open_return == -EACCES) {
+ /*
+ * This happens if the paranoid value
+ * /proc/sys/kernel/perf_event_paranoid is set to 2
+ * Re-run with exclude_kernel set; we don't do that
+ * by default as some ARM machines do not support it.
+ *
+ */
+ evsel->core.attr.exclude_kernel = 1;
+ ret = evsel__open(evsel, NULL, tmap) >= 0;
+ }
+ evsel__delete(evsel);
+ }
+
+ perf_thread_map__put(tmap);
+ return ret;
+}
+
const char *event_type(int type)
{
switch (type) {
diff --git a/tools/perf/util/parse-events.h b/tools/perf/util/parse-events.h
index 7e6a601d9cd0..07df7bb7b042 100644
--- a/tools/perf/util/parse-events.h
+++ b/tools/perf/util/parse-events.h
@@ -19,6 +19,7 @@ struct option;
struct perf_pmu;
bool have_tracepoints(struct list_head *evlist);
+bool is_event_supported(u8 type, u64 config);
const char *event_type(int type);
diff --git a/tools/perf/util/print-events.c b/tools/perf/util/print-events.c
index 04050d4f6db8..c4d5d87fae2f 100644
--- a/tools/perf/util/print-events.c
+++ b/tools/perf/util/print-events.c
@@ -22,7 +22,6 @@
#include "probe-file.h"
#include "string2.h"
#include "strlist.h"
-#include "thread_map.h"
#include "tracepoint.h"
#include "pfm.h"
#include "pmu-hybrid.h"
@@ -239,44 +238,6 @@ void print_sdt_events(const char *subsys_glob, const char *event_glob,
strlist__delete(sdtlist);
}
-static bool is_event_supported(u8 type, u64 config)
-{
- bool ret = true;
- int open_return;
- struct evsel *evsel;
- struct perf_event_attr attr = {
- .type = type,
- .config = config,
- .disabled = 1,
- };
- struct perf_thread_map *tmap = thread_map__new_by_tid(0);
-
- if (tmap == NULL)
- return false;
-
- evsel = evsel__new(&attr);
- if (evsel) {
- open_return = evsel__open(evsel, NULL, tmap);
- ret = open_return >= 0;
-
- if (open_return == -EACCES) {
- /*
- * This happens if the paranoid value
- * /proc/sys/kernel/perf_event_paranoid is set to 2
- * Re-run with exclude_kernel set; we don't do that
- * by default as some ARM machines do not support it.
- *
- */
- evsel->core.attr.exclude_kernel = 1;
- ret = evsel__open(evsel, NULL, tmap) >= 0;
- }
- evsel__delete(evsel);
- }
-
- perf_thread_map__put(tmap);
- return ret;
-}
-
int print_hwcache_events(const char *event_glob, bool name_only)
{
unsigned int type, op, i, evt_i = 0, evt_num = 0, npmus = 0;
--
2.25.1