unimore/kernel-hacking-2024-linux-steffo
unimore/kernel-hacking-2024-linux-steffo
1
Fork 0
Code Pull requests 5 Wiki Activity

perf tools: Add evlist__add_sched_switch()

Browse source 
Add a help to create a system-wide sched_switch event.  One merit is
that it sets the system-wide bit before adding it to evlist so that
the libperf can handle the cpu and thread maps correctly.

Reviewed-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20221003204647.1481128-5-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This commit is contained in:
Namhyung Kim 2022-10-03 13:46:46 -07:00 committed by Arnaldo Carvalho de Melo
parent 60ea006f72
commit 182bb594e0
4 changed files with 28 additions and 20 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

15
tools/perf/arch/x86/util/intel-pt.c
View file

@ -11,6 +11,7 @@
#include <linux/bitops.h>
#include <linux/log2.h>
#include <linux/zalloc.h>
#include <linux/err.h>
#include <cpuid.h>
#include "../../../util/session.h"
@ -426,20 +427,14 @@ static int intel_pt_track_switches(struct evlist *evlist)
if (!evlist__can_select_event(evlist, sched_switch))
return -EPERM;
err = parse_event(evlist, sched_switch);
if (err) {
pr_debug2("%s: failed to parse %s, error %d\n",
evsel = evlist__add_sched_switch(evlist, true);
if (IS_ERR(evsel)) {
err = PTR_ERR(evsel);
pr_debug2("%s: failed to create %s, error = %d\n",
__func__, sched_switch, err);
return err;
}
evsel = evlist__last(evlist);
evsel__set_sample_bit(evsel, CPU);
evsel__set_sample_bit(evsel, TIME);
evsel->core.system_wide = true;
evsel->no_aux_samples = true;
evsel->immediate = true;
return 0;

15
tools/perf/tests/switch-tracking.c
View file

@ -6,6 +6,7 @@
#include <time.h>
#include <stdlib.h>
#include <linux/zalloc.h>
#include <linux/err.h>
#include <perf/cpumap.h>
#include <perf/evlist.h>
#include <perf/mmap.h>
@ -398,19 +399,13 @@ static int test__switch_tracking(struct test_suite *test __maybe_unused, int sub
goto out;
}
err = parse_event(evlist, sched_switch);
if (err) {
pr_debug("Failed to parse event %s\n", sched_switch);
switch_evsel = evlist__add_sched_switch(evlist, true);
if (IS_ERR(switch_evsel)) {
err = PTR_ERR(switch_evsel);
pr_debug("Failed to create event %s\n", sched_switch);
goto out_err;
}
switch_evsel = evlist__last(evlist);
evsel__set_sample_bit(switch_evsel, CPU);
evsel__set_sample_bit(switch_evsel, TIME);
switch_evsel->core.system_wide = true;
switch_evsel->no_aux_samples = true;
switch_evsel->immediate = true;
/* Test moving an event to the front */

17
tools/perf/util/evlist.c
View file

@ -288,6 +288,23 @@ struct evsel *evlist__add_aux_dummy(struct evlist *evlist, bool system_wide)
return evsel;
}
struct evsel *evlist__add_sched_switch(struct evlist *evlist, bool system_wide)
{
struct evsel *evsel = evsel__newtp_idx("sched", "sched_switch", 0);
if (IS_ERR(evsel))
return evsel;
evsel__set_sample_bit(evsel, CPU);
evsel__set_sample_bit(evsel, TIME);
evsel->core.system_wide = system_wide;
evsel->no_aux_samples = true;
evlist__add(evlist, evsel);
return evsel;
};
int evlist__add_attrs(struct evlist *evlist, struct perf_event_attr *attrs, size_t nr_attrs)
{
struct evsel *evsel, *n;

1
tools/perf/util/evlist.h
View file

@ -127,6 +127,7 @@ static inline struct evsel *evlist__add_dummy_on_all_cpus(struct evlist *evlist)
{
return evlist__add_aux_dummy(evlist, true);
}
struct evsel *evlist__add_sched_switch(struct evlist *evlist, bool system_wide);
int evlist__add_sb_event(struct evlist *evlist, struct perf_event_attr *attr,
evsel__sb_cb_t cb, void *data);