[RFC PATCH v17 4/8] perf stat: Plugin retire_lat value from sampled data to evsel

From: weilin . wang
Date: Fri Jul 12 2024 - 15:10:28 EST


From: Weilin Wang <weilin.wang@xxxxxxxxx>

In current :R parsing implementation, the parser would recognize events with
retire_latency modifier and insert them into the evlist like a normal event.
Ideally, we need to avoid counting these events.

In this commit, at the time when a retire_latency evsel is read, set the retire
latency value processed from the sampled data to count value. This sampled
retire latency value will be used for metric calculation and final event count
print out. No special metric calculation and event print out code required for
retire_latency events.

Signed-off-by: Weilin Wang <weilin.wang@xxxxxxxxx>
---
tools/perf/arch/x86/util/evlist.c | 6 ++++++
tools/perf/util/evsel.c | 15 +++++++++++++++
tools/perf/util/evsel.h | 5 +++++
3 files changed, 26 insertions(+)

diff --git a/tools/perf/arch/x86/util/evlist.c b/tools/perf/arch/x86/util/evlist.c
index b1ce0c52d88d..cebdd483149e 100644
--- a/tools/perf/arch/x86/util/evlist.c
+++ b/tools/perf/arch/x86/util/evlist.c
@@ -89,6 +89,12 @@ int arch_evlist__cmp(const struct evsel *lhs, const struct evsel *rhs)
return 1;
}

+ /* Retire latency event should not be group leader*/
+ if (lhs->retire_lat && !rhs->retire_lat)
+ return 1;
+ if (!lhs->retire_lat && rhs->retire_lat)
+ return -1;
+
/* Default ordering by insertion index. */
return lhs->core.idx - rhs->core.idx;
}
diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
index 1d000fa2c6cf..d607056b73c9 100644
--- a/tools/perf/util/evsel.c
+++ b/tools/perf/util/evsel.c
@@ -59,6 +59,7 @@
#include <internal/xyarray.h>
#include <internal/lib.h>
#include <internal/threadmap.h>
+#include "util/intel-tpebs.h"

#include <linux/ctype.h>

@@ -1539,6 +1540,11 @@ static int evsel__read_one(struct evsel *evsel, int cpu_map_idx, int thread)
return perf_evsel__read(&evsel->core, cpu_map_idx, thread, count);
}

+static int evsel__read_retire_lat(struct evsel *evsel, int cpu_map_idx, int thread)
+{
+ return tpebs_set_evsel(evsel, cpu_map_idx, thread);
+}
+
static void evsel__set_count(struct evsel *counter, int cpu_map_idx, int thread,
u64 val, u64 ena, u64 run, u64 lost)
{
@@ -1546,6 +1552,12 @@ static void evsel__set_count(struct evsel *counter, int cpu_map_idx, int thread,

count = perf_counts(counter->counts, cpu_map_idx, thread);

+ if (counter->retire_lat) {
+ evsel__read_retire_lat(counter, cpu_map_idx, thread);
+ perf_counts__set_loaded(counter->counts, cpu_map_idx, thread, true);
+ return;
+ }
+
count->val = val;
count->ena = ena;
count->run = run;
@@ -1838,6 +1850,9 @@ int evsel__read_counter(struct evsel *evsel, int cpu_map_idx, int thread)
if (evsel__is_tool(evsel))
return evsel__read_tool(evsel, cpu_map_idx, thread);

+ if (evsel__is_retire_lat(evsel))
+ return evsel__read_retire_lat(evsel, cpu_map_idx, thread);
+
if (evsel->core.attr.read_format & PERF_FORMAT_GROUP)
return evsel__read_group(evsel, cpu_map_idx, thread);

diff --git a/tools/perf/util/evsel.h b/tools/perf/util/evsel.h
index 14f777b9e03e..a5da4b03bb1c 100644
--- a/tools/perf/util/evsel.h
+++ b/tools/perf/util/evsel.h
@@ -311,6 +311,11 @@ static inline bool evsel__is_tool(const struct evsel *evsel)
return evsel->tool_event != PERF_TOOL_NONE;
}

+static inline bool evsel__is_retire_lat(const struct evsel *evsel)
+{
+ return evsel->retire_lat;
+}
+
const char *evsel__group_name(struct evsel *evsel);
int evsel__group_desc(struct evsel *evsel, char *buf, size_t size);

--
2.43.0