Commit ceb13bfc authored by Namhyung Kim's avatar Namhyung Kim Committed by Arnaldo Carvalho de Melo
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perf lock: Add --map-nr-entries option 



The --map-nr-entries option is to control number of max entries in the
perf lock contention BPF maps.

Signed-off-by: default avatarNamhyung Kim <namhyung@kernel.org>
Cc: Blake Jones <blakejones@google.com>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Song Liu <songliubraving@fb.com>
Cc: Waiman Long <longman@redhat.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20220802191004.347740-2-namhyung@kernel.org


Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
parent 447ec4e5

tools/perf/Documentation/perf-lock.txt

+3 −0
Original line number Diff line number Diff line
@@ -145,6 +145,9 @@ CONTENTION OPTIONS 
--tid=::

        Record events on existing thread ID (comma separated list).



--map-nr-entries::

	Maximum number of BPF map entries (default: 10240).





SEE ALSO

--------

tools/perf/builtin-lock.c

+22 −1
Original line number Diff line number Diff line
@@ -56,6 +56,7 @@ static struct rb_root thread_stats; 
static bool combine_locks;

static bool show_thread_stats;

static bool use_bpf;

static unsigned long bpf_map_entries = 10240;



static enum {

	LOCK_AGGR_ADDR,
@@ -1598,6 +1599,7 @@ static int __cmd_contention(int argc, const char **argv) 
	struct lock_contention con = {

		.target = &target,

		.result = &lockhash_table[0],

		.map_nr_entries = bpf_map_entries,

	};



	session = perf_session__new(use_bpf ? NULL : &data, &eops);
@@ -1787,6 +1789,24 @@ static int __cmd_record(int argc, const char **argv) 
	return ret;

}



static int parse_map_entry(const struct option *opt, const char *str,

			    int unset __maybe_unused)

{

	unsigned long *len = (unsigned long *)opt->value;

	unsigned long val;

	char *endptr;



	errno = 0;

	val = strtoul(str, &endptr, 0);

	if (*endptr != '\0' || errno != 0) {

		pr_err("invalid BPF map length: %s\n", str);

		return -1;

	}



	*len = val;

	return 0;

}



int cmd_lock(int argc, const char **argv)

{

	const struct option lock_options[] = {
@@ -1836,9 +1856,10 @@ int cmd_lock(int argc, const char **argv) 
		    "List of cpus to monitor"),

	OPT_STRING('p', "pid", &target.pid, "pid",

		   "Trace on existing process id"),

	/* TODO: Add short option -t after -t/--tracer can be removed. */

	OPT_STRING(0, "tid", &target.tid, "tid",

		   "Trace on existing thread id (exclusive to --pid)"),

	OPT_CALLBACK(0, "map-nr-entries", &bpf_map_entries, "num",

		     "Max number of BPF map entries", parse_map_entry),

	OPT_PARENT(lock_options)

	};

tools/perf/util/bpf_lock_contention.c

+3 −0
Original line number Diff line number Diff line
@@ -40,6 +40,9 @@ int lock_contention_prepare(struct lock_contention *con) 
		return -1;

	}



	bpf_map__set_max_entries(skel->maps.stacks, con->map_nr_entries);

	bpf_map__set_max_entries(skel->maps.lock_stat, con->map_nr_entries);



	if (target__has_cpu(target))

		ncpus = perf_cpu_map__nr(evlist->core.user_requested_cpus);

	if (target__has_task(target))

tools/perf/util/lock-contention.h

+1 −0
Original line number Diff line number Diff line
@@ -112,6 +112,7 @@ struct lock_contention { 
	struct target *target;

	struct machine *machine;

	struct hlist_head *result;

	unsigned long map_nr_entries;

};



#ifdef HAVE_BPF_SKEL