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: Arnaldo Carvalho de Melo <acme@redhat.com>
This commit is contained in:
Arnaldo Carvalho de Melo 2018-11-07 10:08:00 -03:00
parent 744fafc787
commit a9964c432b

View File

@ -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;