Commit c30d630d authored Dec 04, 2019 by David Ahern Committed by Arnaldo Carvalho de Melo Jan 06, 2020

perf sched timehist: Add support for filtering on CPU



Allow user to limit output to one or more CPUs. Really helpful on
systems with a large number of cpus.

Committer testing:

  # perf sched record -a sleep 1
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 1.765 MB perf.data (1412 samples) ]
  [root@quaco ~]# perf sched timehist | head
  Samples do not have callchains.
             time    cpu  task name                       wait time  sch delay   run time
                          [tid/pid]                          (msec)     (msec)     (msec)
  --------------- ------  ------------------------------  ---------  ---------  ---------
     66307.802686 [0000]  perf[13086]                         0.000      0.000      0.000
     66307.802700 [0000]  migration/0[12]                     0.000      0.001      0.014
     66307.802766 [0001]  perf[13086]                         0.000      0.000      0.000
     66307.802774 [0001]  migration/1[15]                     0.000      0.001      0.007
     66307.802841 [0002]  perf[13086]                         0.000      0.000      0.000
     66307.802849 [0002]  migration/2[20]                     0.000      0.001      0.008
     66307.802913 [0003]  perf[13086]                         0.000      0.000      0.000
  #
  # perf sched timehist --cpu 2 | head
  Samples do not have callchains.
             time    cpu  task name                       wait time  sch delay   run time
                          [tid/pid]                          (msec)     (msec)     (msec)
  --------------- ------  ------------------------------  ---------  ---------  ---------
     66307.802841 [0002]  perf[13086]                         0.000      0.000      0.000
     66307.802849 [0002]  migration/2[20]                     0.000      0.001      0.008
     66307.964485 [0002]  <idle>                              0.000      0.000    161.635
     66307.964811 [0002]  CPU 0/KVM[3589/3561]                0.000      0.056      0.325
     66307.965477 [0002]  <idle>                              0.325      0.000      0.666
     66307.965553 [0002]  CPU 0/KVM[3589/3561]                0.666      0.024      0.076
     66307.966456 [0002]  <idle>                              0.076      0.000      0.903
  #

Signed-off-by: David Ahern <dsahern@gmail.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lore.kernel.org/lkml/20191204173925.66976-1-dsahern@kernel.org


Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

parent 8384a260

tools/perf/Documentation/perf-sched.txt

+4 −0

Original line number	Diff line number	Diff line
		@@ -110,6 +110,10 @@ OPTIONS for 'perf sched timehist'
		--max-stack::
		Maximum number of functions to display in backtrace, default 5.

		-C=::
		--cpu=::
		Only show events for the given CPU(s) (comma separated list).

		-p=::
		--pid=::
		Only show events for given process ID (comma separated list).

tools/perf/builtin-sched.c

+13 −0

Original line number	Diff line number	Diff line
		@@ -51,6 +51,9 @@
		#define SYM_LEN 129
		#define MAX_PID 1024000

		static const char *cpu_list;
		static DECLARE_BITMAP(cpu_bitmap, MAX_NR_CPUS);

		struct sched_atom;

		struct task_desc {
		@@ -2008,6 +2011,9 @@ static void timehist_print_sample(struct perf_sched *sched,
		char nstr[30];
		u64 wait_time;

		if (cpu_list && !test_bit(sample->cpu, cpu_bitmap))
		return;

		timestamp__scnprintf_usec(t, tstr, sizeof(tstr));
		printf("%15s [%04d] ", tstr, sample->cpu);

		@@ -2994,6 +3000,12 @@ static int perf_sched__timehist(struct perf_sched *sched)
		if (IS_ERR(session))
		return PTR_ERR(session);

		if (cpu_list) {
		err = perf_session__cpu_bitmap(session, cpu_list, cpu_bitmap);
		if (err < 0)
		goto out;
		}

		evlist = session->evlist;

		symbol__init(&session->header.env);
		@@ -3429,6 +3441,7 @@ int cmd_sched(int argc, const char **argv)
		"analyze events only for given process id(s)"),
		OPT_STRING('t', "tid", &symbol_conf.tid_list_str, "tid[,tid...]",
		"analyze events only for given thread id(s)"),
		OPT_STRING('C', "cpu", &cpu_list, "cpu", "list of cpus to profile"),
		OPT_PARENT(sched_options)
		};

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