Commit a9964c43 authored by Arnaldo Carvalho de Melo's avatar Arnaldo Carvalho de Melo
Browse files

perf trace: Fill in BPF "filtered_pids" map when present 

This makes the augmented_syscalls support the --filter-pids and
auto-filtered feedback loop pids just like when working without BPF,
i.e. with just raw_syscalls:sys_{enter,exit} and tracepoint filters.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-zc5n453sxxm0tz1zfwwelyti@git.kernel.org


Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
parent 744fafc7

tools/perf/builtin-trace.c

+48 −13
Original line number Diff line number Diff line
@@ -2567,9 +2567,27 @@ out_enomem: 
	goto out;

}



static int bpf_map__set_filter_pids(struct bpf_map *map __maybe_unused,

				    size_t npids __maybe_unused, pid_t *pids __maybe_unused)

{

	int err = 0;

#ifdef HAVE_LIBBPF_SUPPORT

	bool value = true;

	int map_fd = bpf_map__fd(map);

	size_t i;



	for (i = 0; i < npids; ++i) {

		err = bpf_map_update_elem(map_fd, &pids[i], &value, BPF_ANY);

		if (err)

			break;

	}

#endif

	return err;

}



static int trace__set_filter_loop_pids(struct trace *trace)

{

	unsigned int nr = 1;

	unsigned int nr = 1, err;

	pid_t pids[32] = {

		getpid(),

	};
@@ -2588,7 +2606,34 @@ static int trace__set_filter_loop_pids(struct trace *trace) 
		thread = parent;

	}



	return perf_evlist__set_tp_filter_pids(trace->evlist, nr, pids);

	err = perf_evlist__set_tp_filter_pids(trace->evlist, nr, pids);

	if (!err && trace->filter_pids.map)

		err = bpf_map__set_filter_pids(trace->filter_pids.map, nr, pids);



	return err;

}



static int trace__set_filter_pids(struct trace *trace)

{

	int err = 0;

	/*

	 * Better not use !target__has_task() here because we need to cover the

	 * case where no threads were specified in the command line, but a

	 * workload was, and in that case we will fill in the thread_map when

	 * we fork the workload in perf_evlist__prepare_workload.

	 */

	if (trace->filter_pids.nr > 0) {

		err = perf_evlist__set_tp_filter_pids(trace->evlist, trace->filter_pids.nr,

						      trace->filter_pids.entries);

		if (!err && trace->filter_pids.map) {

			err = bpf_map__set_filter_pids(trace->filter_pids.map, trace->filter_pids.nr,

						       trace->filter_pids.entries);

		}

	} else if (thread_map__pid(trace->evlist->threads, 0) == -1) {

		err = trace__set_filter_loop_pids(trace);

	}



	return err;

}



static int trace__run(struct trace *trace, int argc, const char **argv)
@@ -2697,17 +2742,7 @@ static int trace__run(struct trace *trace, int argc, const char **argv) 
		goto out_error_open;

	}



	/*

	 * Better not use !target__has_task() here because we need to cover the

	 * case where no threads were specified in the command line, but a

	 * workload was, and in that case we will fill in the thread_map when

	 * we fork the workload in perf_evlist__prepare_workload.

	 */

	if (trace->filter_pids.nr > 0)

		err = perf_evlist__set_tp_filter_pids(evlist, trace->filter_pids.nr, trace->filter_pids.entries);

	else if (thread_map__pid(evlist->threads, 0) == -1)

		err = trace__set_filter_loop_pids(trace);



	err = trace__set_filter_pids(trace);

	if (err < 0)

		goto out_error_mem;

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