mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-21 16:29:59 +00:00
![Ian Rogers](/assets/img/avatar_default.png)
evlist contains cpus and all_cpus. all_cpus is the union of the cpu maps of all evsels. For non-task targets, cpus is set to be cpus requested from the command line, defaulting to all online cpus if no cpus are specified. For an uncore event, all_cpus may be just CPU 0 or every online CPU. This causes all_cpus to have fewer values than the cpus variable which is confusing given the 'all' in the name. To try to make the behavior clearer, rename cpus to user_requested_cpus and add comments on the two struct variables. Signed-off-by: Ian Rogers <irogers@google.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Antonov <alexander.antonov@linux.intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Alexey Bayduraev <alexey.v.bayduraev@linux.intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Andrii Nakryiko <andrii@kernel.org> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: German Gomez <german.gomez@arm.com> Cc: James Clark <james.clark@arm.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: John Fastabend <john.fastabend@gmail.com> Cc: John Garry <john.garry@huawei.com> Cc: KP Singh <kpsingh@kernel.org> Cc: Kajol Jain <kjain@linux.ibm.com> Cc: Leo Yan <leo.yan@linaro.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Martin KaFai Lau <kafai@fb.com> Cc: Mathieu Poirier <mathieu.poirier@linaro.org> Cc: Mike Leach <mike.leach@linaro.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Riccardo Mancini <rickyman7@gmail.com> Cc: Song Liu <songliubraving@fb.com> Cc: Stephane Eranian <eranian@google.com> Cc: Suzuki Poulouse <suzuki.poulose@arm.com> Cc: Will Deacon <will@kernel.org> Cc: Yonghong Song <yhs@fb.com> Cc: bpf@vger.kernel.org Cc: coresight@lists.linaro.org Cc: linux-arm-kernel@lists.infradead.org Cc: netdev@vger.kernel.org Link: http://lore.kernel.org/lkml/20220328232648.2127340-3-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
149 lines
3.4 KiB
C
149 lines
3.4 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
|
|
|
|
#include "util/debug.h"
|
|
#include "util/evlist.h"
|
|
#include "util/evsel.h"
|
|
#include "util/mmap.h"
|
|
#include "util/perf_api_probe.h"
|
|
#include <perf/mmap.h>
|
|
#include <linux/perf_event.h>
|
|
#include <limits.h>
|
|
#include <pthread.h>
|
|
#include <sched.h>
|
|
#include <stdbool.h>
|
|
|
|
int evlist__add_sb_event(struct evlist *evlist, struct perf_event_attr *attr,
|
|
evsel__sb_cb_t cb, void *data)
|
|
{
|
|
struct evsel *evsel;
|
|
|
|
if (!attr->sample_id_all) {
|
|
pr_warning("enabling sample_id_all for all side band events\n");
|
|
attr->sample_id_all = 1;
|
|
}
|
|
|
|
evsel = evsel__new_idx(attr, evlist->core.nr_entries);
|
|
if (!evsel)
|
|
return -1;
|
|
|
|
evsel->side_band.cb = cb;
|
|
evsel->side_band.data = data;
|
|
evlist__add(evlist, evsel);
|
|
return 0;
|
|
}
|
|
|
|
static void *perf_evlist__poll_thread(void *arg)
|
|
{
|
|
struct evlist *evlist = arg;
|
|
bool draining = false;
|
|
int i, done = 0;
|
|
/*
|
|
* In order to read symbols from other namespaces perf to needs to call
|
|
* setns(2). This isn't permitted if the struct_fs has multiple users.
|
|
* unshare(2) the fs so that we may continue to setns into namespaces
|
|
* that we're observing when, for instance, reading the build-ids at
|
|
* the end of a 'perf record' session.
|
|
*/
|
|
unshare(CLONE_FS);
|
|
|
|
while (!done) {
|
|
bool got_data = false;
|
|
|
|
if (evlist->thread.done)
|
|
draining = true;
|
|
|
|
if (!draining)
|
|
evlist__poll(evlist, 1000);
|
|
|
|
for (i = 0; i < evlist->core.nr_mmaps; i++) {
|
|
struct mmap *map = &evlist->mmap[i];
|
|
union perf_event *event;
|
|
|
|
if (perf_mmap__read_init(&map->core))
|
|
continue;
|
|
while ((event = perf_mmap__read_event(&map->core)) != NULL) {
|
|
struct evsel *evsel = evlist__event2evsel(evlist, event);
|
|
|
|
if (evsel && evsel->side_band.cb)
|
|
evsel->side_band.cb(event, evsel->side_band.data);
|
|
else
|
|
pr_warning("cannot locate proper evsel for the side band event\n");
|
|
|
|
perf_mmap__consume(&map->core);
|
|
got_data = true;
|
|
}
|
|
perf_mmap__read_done(&map->core);
|
|
}
|
|
|
|
if (draining && !got_data)
|
|
break;
|
|
}
|
|
return NULL;
|
|
}
|
|
|
|
void evlist__set_cb(struct evlist *evlist, evsel__sb_cb_t cb, void *data)
|
|
{
|
|
struct evsel *evsel;
|
|
|
|
evlist__for_each_entry(evlist, evsel) {
|
|
evsel->core.attr.sample_id_all = 1;
|
|
evsel->core.attr.watermark = 1;
|
|
evsel->core.attr.wakeup_watermark = 1;
|
|
evsel->side_band.cb = cb;
|
|
evsel->side_band.data = data;
|
|
}
|
|
}
|
|
|
|
int evlist__start_sb_thread(struct evlist *evlist, struct target *target)
|
|
{
|
|
struct evsel *counter;
|
|
|
|
if (!evlist)
|
|
return 0;
|
|
|
|
if (evlist__create_maps(evlist, target))
|
|
goto out_delete_evlist;
|
|
|
|
if (evlist->core.nr_entries > 1) {
|
|
bool can_sample_identifier = perf_can_sample_identifier();
|
|
|
|
evlist__for_each_entry(evlist, counter)
|
|
evsel__set_sample_id(counter, can_sample_identifier);
|
|
|
|
evlist__set_id_pos(evlist);
|
|
}
|
|
|
|
evlist__for_each_entry(evlist, counter) {
|
|
if (evsel__open(counter, evlist->core.user_requested_cpus,
|
|
evlist->core.threads) < 0)
|
|
goto out_delete_evlist;
|
|
}
|
|
|
|
if (evlist__mmap(evlist, UINT_MAX))
|
|
goto out_delete_evlist;
|
|
|
|
evlist__for_each_entry(evlist, counter) {
|
|
if (evsel__enable(counter))
|
|
goto out_delete_evlist;
|
|
}
|
|
|
|
evlist->thread.done = 0;
|
|
if (pthread_create(&evlist->thread.th, NULL, perf_evlist__poll_thread, evlist))
|
|
goto out_delete_evlist;
|
|
|
|
return 0;
|
|
|
|
out_delete_evlist:
|
|
evlist__delete(evlist);
|
|
evlist = NULL;
|
|
return -1;
|
|
}
|
|
|
|
void evlist__stop_sb_thread(struct evlist *evlist)
|
|
{
|
|
if (!evlist)
|
|
return;
|
|
evlist->thread.done = 1;
|
|
pthread_join(evlist->thread.th, NULL);
|
|
evlist__delete(evlist);
|
|
}
|