perf trace: See if there is a map named "filtered_pids"

Lookup for the first map named "filtered_pids" and, if augmenting
syscalls, i.e. if a BPF event is present and the
"__augmented_syscalls__" is present, then fill in that map with the pids
to filter, be it feedback loop ones (perf trace's pid, its father if it
is "sshd", more auto-filtered in the future) or the ones explicitely
stated in the tool command line via --filter-pids.

The code to actually fill in the map comes next.

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-rhzytmw7qpe6lqyjxi1ded9t@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 10:04:51 -03:00
parent 6a0b3abad9
commit 744fafc787

View File

@ -18,6 +18,7 @@
#include <traceevent/event-parse.h> #include <traceevent/event-parse.h>
#include <api/fs/tracing_path.h> #include <api/fs/tracing_path.h>
#include <bpf/bpf.h>
#include "builtin.h" #include "builtin.h"
#include "util/cgroup.h" #include "util/cgroup.h"
#include "util/color.h" #include "util/color.h"
@ -99,6 +100,7 @@ struct trace {
struct { struct {
size_t nr; size_t nr;
pid_t *entries; pid_t *entries;
struct bpf_map *map;
} filter_pids; } filter_pids;
double duration_filter; double duration_filter;
double runtime_ms; double runtime_ms;
@ -3315,6 +3317,25 @@ static int trace__parse_cgroups(const struct option *opt, const char *str, int u
return 0; return 0;
} }
static struct bpf_map *bpf__find_map_by_name(const char *name)
{
struct bpf_object *obj, *tmp;
bpf_object__for_each_safe(obj, tmp) {
struct bpf_map *map = bpf_object__find_map_by_name(obj, name);
if (map)
return map;
}
return NULL;
}
static void trace__set_bpf_map_filtered_pids(struct trace *trace)
{
trace->filter_pids.map = bpf__find_map_by_name("pids_filtered");
}
int cmd_trace(int argc, const char **argv) int cmd_trace(int argc, const char **argv)
{ {
const char *trace_usage[] = { const char *trace_usage[] = {
@ -3451,8 +3472,10 @@ int cmd_trace(int argc, const char **argv)
goto out; goto out;
} }
if (evsel) if (evsel) {
trace.syscalls.events.augmented = evsel; trace.syscalls.events.augmented = evsel;
trace__set_bpf_map_filtered_pids(&trace);
}
err = bpf__setup_stdout(trace.evlist); err = bpf__setup_stdout(trace.evlist);
if (err) { if (err) {