linux-stable/tools/perf/util/evswitch.c
Arnaldo Carvalho de Melo 8b3c9ea7bf perf evswitch: Add hint when not finding specified on/off events
If the user specifies a on or off switch event and it isn't in the
perf.data file, provide a hint about how to see the events in the
perf.data evlist:

  # perf script --switch-on=syscall:sys_enter_nanosleep --switch-off=syscalls:sys_exit_nanosleep
  ERROR: event_on event not found (syscall:sys_enter_nanosleep)
  HINT:  use 'perf evlist' to see the available event names
  #
  # perf evlist
  sched:sched_kthread_stop
  sched:sched_kthread_stop_ret
  sched:sched_waking
  sched:sched_wakeup
  sched:sched_wakeup_new
  sched:sched_switch
  sched:sched_migrate_task
  sched:sched_process_free
  sched:sched_process_exit
  sched:sched_wait_task
  sched:sched_process_wait
  sched:sched_process_fork
  sched:sched_process_exec
  sched:sched_stat_wait
  sched:sched_stat_sleep
  sched:sched_stat_iowait
  sched:sched_stat_blocked
  sched:sched_stat_runtime
  sched:sched_pi_setprio
  sched:sched_move_numa
  sched:sched_stick_numa
  sched:sched_swap_numa
  sched:sched_wake_idle_without_ipi
  syscalls:sys_enter_clock_nanosleep
  syscalls:sys_exit_clock_nanosleep
  syscalls:sys_enter_nanosleep
  syscalls:sys_exit_nanosleep
  # Tip: use 'perf evlist --trace-fields' to show fields for tracepoint events
  #
  # perf script --switch-on=syscalls:sys_enter_nanosleep --switch-off=syscalls:sys_exit_nanosleep
       sleep 20919 [001] 109866.144411:  sched:sched_stat_runtime: comm=sleep pid=20919 runtime=521249 [ns] vruntime=202919398131 [ns]
       sleep 20919 [001] 109866.144412:        sched:sched_switch: sleep:20919 [120] S ==> swapper/1:0 [120]
     swapper     0 [001] 109867.144568:        sched:sched_waking: comm=sleep pid=20919 prio=120 target_cpu=001
     swapper     0 [001] 109867.144586:        sched:sched_wakeup: sleep:20919 [120] success=1 CPU:001
  #

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Florian Weimer <fweimer@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: William Cohen <wcohen@redhat.com>
Link: https://lkml.kernel.org/n/tip-iijjvdlyad973oskdq8gmi5w@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-08-15 12:26:13 -03:00

61 lines
1.4 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
// Copyright (C) 2019, Red Hat Inc, Arnaldo Carvalho de Melo <acme@redhat.com>
#include "evswitch.h"
#include "evlist.h"
bool evswitch__discard(struct evswitch *evswitch, struct evsel *evsel)
{
if (evswitch->on && evswitch->discarding) {
if (evswitch->on != evsel)
return true;
evswitch->discarding = false;
if (!evswitch->show_on_off_events)
return true;
return false;
}
if (evswitch->off && !evswitch->discarding) {
if (evswitch->off != evsel)
return false;
evswitch->discarding = true;
if (!evswitch->show_on_off_events)
return true;
}
return false;
}
static int evswitch__fprintf_enoent(FILE *fp, const char *evtype, const char *evname)
{
int printed = fprintf(fp, "ERROR: switch-%s event not found (%s)\n", evtype, evname);
return printed += fprintf(fp, "HINT: use 'perf evlist' to see the available event names\n");
}
int evswitch__init(struct evswitch *evswitch, struct evlist *evlist, FILE *fp)
{
if (evswitch->on_name) {
evswitch->on = perf_evlist__find_evsel_by_str(evlist, evswitch->on_name);
if (evswitch->on == NULL) {
evswitch__fprintf_enoent(fp, "on", evswitch->on_name);
return -ENOENT;
}
evswitch->discarding = true;
}
if (evswitch->off_name) {
evswitch->off = perf_evlist__find_evsel_by_str(evlist, evswitch->off_name);
if (evswitch->off == NULL) {
evswitch__fprintf_enoent(fp, "off", evswitch->off_name);
return -ENOENT;
}
}
return 0;
}