Commit d45ce034 authored by Riccardo Mancini's avatar Riccardo Mancini Committed by Arnaldo Carvalho de Melo
Browse files

perf evsel: Separate open preparation from open itself 



This is a preparatory patch for the following patches with the goal to
separate in evlist__open_cpu the actual perf_event_open, which could be
performed in parallel, from the existing fallback mechanisms, which
should be handled sequentially.

This patch separates the first lines of evsel__open_cpu into a new
__evsel__prepare_open function.

Signed-off-by: default avatarRiccardo Mancini <rickyman7@gmail.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/e14118b934c338dbbf68b8677f20d0d7dbf9359a.1629490974.git.rickyman7@gmail.com


Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
parent bc049604

tools/perf/util/evsel.c

+34 −11
Original line number Diff line number Diff line
@@ -1746,22 +1746,20 @@ static int perf_event_open(struct evsel *evsel, 
	return fd;

}



static int evsel__open_cpu(struct evsel *evsel, struct perf_cpu_map *cpus,

		struct perf_thread_map *threads,

		int start_cpu, int end_cpu)



static struct perf_cpu_map *empty_cpu_map;

static struct perf_thread_map *empty_thread_map;



static int __evsel__prepare_open(struct evsel *evsel, struct perf_cpu_map *cpus,

		struct perf_thread_map *threads)

{

	int cpu, thread, nthreads;

	unsigned long flags = PERF_FLAG_FD_CLOEXEC;

	int pid = -1, err, old_errno;

	enum { NO_CHANGE, SET_TO_MAX, INCREASED_MAX } set_rlimit = NO_CHANGE;

	int nthreads;



	if ((perf_missing_features.write_backward && evsel->core.attr.write_backward) ||

	    (perf_missing_features.aux_output     && evsel->core.attr.aux_output))

		return -EINVAL;



	if (cpus == NULL) {

		static struct perf_cpu_map *empty_cpu_map;



		if (empty_cpu_map == NULL) {

			empty_cpu_map = perf_cpu_map__dummy_new();

			if (empty_cpu_map == NULL)
@@ -1772,8 +1770,6 @@ static int evsel__open_cpu(struct evsel *evsel, struct perf_cpu_map *cpus, 
	}



	if (threads == NULL) {

		static struct perf_thread_map *empty_thread_map;



		if (empty_thread_map == NULL) {

			empty_thread_map = thread_map__new_by_tid(-1);

			if (empty_thread_map == NULL)
@@ -1792,6 +1788,33 @@ static int evsel__open_cpu(struct evsel *evsel, struct perf_cpu_map *cpus, 
	    perf_evsel__alloc_fd(&evsel->core, cpus->nr, nthreads) < 0)

		return -ENOMEM;



	return 0;

}



static int evsel__open_cpu(struct evsel *evsel, struct perf_cpu_map *cpus,

		struct perf_thread_map *threads,

		int start_cpu, int end_cpu)

{

	int cpu, thread, nthreads;

	unsigned long flags = PERF_FLAG_FD_CLOEXEC;

	int pid = -1, err, old_errno;

	enum { NO_CHANGE, SET_TO_MAX, INCREASED_MAX } set_rlimit = NO_CHANGE;



	err = __evsel__prepare_open(evsel, cpus, threads);

	if (err)

		return err;



	if (cpus == NULL)

		cpus = empty_cpu_map;



	if (threads == NULL)

		threads = empty_thread_map;



	if (evsel->core.system_wide)

		nthreads = 1;

	else

		nthreads = threads->nr;



	if (evsel->cgrp) {

		flags |= PERF_FLAG_PID_CGROUP;

		pid = evsel->cgrp->fd;