@@ -43,6 +43,10 @@ Default is to monitor all CPUS.
encoding with the layout of the event control registers as described
by entries in /sys/bus/event_source/devices/cpu/format/*.
+--filter=<filter>::
+ Event filter. This option should follow an event selector (-e). For
+ syntax see linkperf:perf-record[1].
+
-E <entries>::
--entries=<entries>::
Display this many functions.
@@ -1055,6 +1055,13 @@ static int perf_top__start_counters(struct perf_top *top)
}
}
+ if (evlist__apply_filters(evlist, &counter)) {
+ pr_err("failed to set filter \"%s\" on event %s with %d (%s)\n",
+ counter->filter ?: "BPF", evsel__name(counter), errno,
+ str_error_r(errno, msg, sizeof(msg)));
+ goto out_err;
+ }
+
if (evlist__mmap(evlist, opts->mmap_pages) < 0) {
ui__error("Failed to mmap with %d (%s)\n",
errno, str_error_r(errno, msg, sizeof(msg)));
@@ -1462,6 +1469,8 @@ int cmd_top(int argc, const char **argv)
OPT_CALLBACK('e', "event", &parse_events_option_args, "event",
"event selector. use 'perf list' to list available events",
parse_events_option),
+ OPT_CALLBACK(0, "filter", &top.evlist, "filter",
+ "event filter", parse_filter),
OPT_U64('c', "count", &opts->user_interval, "event period to sample"),
OPT_STRING('p', "pid", &target->pid, "pid",
"profile events on existing process id"),
Allow filters to be added to perf top events. One use is to workaround issues with: ``` $ perf top --uid="$(id -u)" ``` which tries to scan /proc find processes belonging to the uid and can fail in such a pid terminates between the scan and the perf_event_open reporting: ``` Error: The sys_perf_event_open() syscall returned with 3 (No such process) for event (cycles:P). /bin/dmesg | grep -i perf may provide additional information. ``` A similar filter: ``` $ perf top -e cycles:P --filter "uid == $(id -u)" ``` doesn't fail this way. Signed-off-by: Ian Rogers <irogers@google.com> --- tools/perf/Documentation/perf-top.txt | 4 ++++ tools/perf/builtin-top.c | 9 +++++++++ 2 files changed, 13 insertions(+)