perf sched stats: Add support for live mode

The live mode works similar to simple `perf stat` command, by profiling
the target and printing results on the terminal as soon as the target
finishes.

Example usage:

  # perf sched stats -- true
  Description
  ----------------------------------------------------------------------------------------------------
  DESC                          -> Description of the field
  COUNT                         -> Value of the field
  PCT_CHANGE                    -> Percent change with corresponding base value
  AVG_JIFFIES                   -> Avg time in jiffies between two consecutive occurrence of event
  ----------------------------------------------------------------------------------------------------

  Time elapsed (in jiffies)                                        :           1
  ----------------------------------------------------------------------------------------------------
  CPU: <ALL CPUS SUMMARY>
  ----------------------------------------------------------------------------------------------------
  DESC                                                                     COUNT   PCT_CHANGE
  ----------------------------------------------------------------------------------------------------
  yld_count                                                        :           0
  array_exp                                                        :           0
  sched_count                                                      :           0
  sched_goidle                                                     :           0  (     0.00% )
  ttwu_count                                                       :           0
  ttwu_local                                                       :           0  (     0.00% )
  rq_cpu_time                                                      :       27875
  run_delay                                                        :           0  (     0.00% )
  pcount                                                           :           0
  ----------------------------------------------------------------------------------------------------
  CPU: <ALL CPUS SUMMARY> | DOMAIN: SMT
  ----------------------------------------------------------------------------------------------------
  DESC                                                                     COUNT    AVG_JIFFIES
  ----------------------------------------- <Category busy> ------------------------------------------
  busy_lb_count                                                    :           0  $        0.00 $
  busy_lb_balanced                                                 :           0  $        0.00 $
  busy_lb_failed                                                   :           0  $        0.00 $
  busy_lb_imbalance_load                                           :           0
  busy_lb_imbalance_util                                           :           0
  busy_lb_imbalance_task                                           :           0
  busy_lb_imbalance_misfit                                         :           0
  busy_lb_gained                                                   :           0
  busy_lb_hot_gained                                               :           0
  busy_lb_nobusyq                                                  :           0  $        0.00 $
  busy_lb_nobusyg                                                  :           0  $        0.00 $
  *busy_lb_success_count                                           :           0
  *busy_lb_avg_pulled                                              :        0.00

  ... and so on. Output will show similar data for all the cpus in the
system.

Co-developed-by: Ravi Bangoria <ravi.bangoria@amd.com>
Signed-off-by: Ravi Bangoria <ravi.bangoria@amd.com>
Signed-off-by: Swapnil Sapkal <swapnil.sapkal@amd.com>
Tested-by: Chen Yu <yu.c.chen@intel.com>
Tested-by: James Clark <james.clark@linaro.org>
Acked-by: Ian Rogers <irogers@google.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Anubhav Shelat <ashelat@redhat.com>
Cc: Ben Gainey <ben.gainey@arm.com>
Cc: Blake Jones <blakejones@google.com>
Cc: Chun-Tse Shao <ctshao@google.com>
Cc: David Vernet <void@manifault.com>
Cc: Dmitriy Vyukov <dvyukov@google.com>
Cc: Dr. David Alan Gilbert <linux@treblig.org>
Cc: Gautham Shenoy <gautham.shenoy@amd.com>
Cc: Graham Woodward <graham.woodward@arm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@arm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: K Prateek Nayak <kprateek.nayak@amd.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Leo Yan <leo.yan@arm.com>
Cc: Madadi Vineeth Reddy <vineethr@linux.ibm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Sandipan Das <sandipan.das@amd.com>
Cc: Santosh Shukla <santosh.shukla@amd.com>
Cc: Shrikanth Hegde <sshegde@linux.ibm.com>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Thomas Falcon <thomas.falcon@intel.com>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Vincent Guittot <vincent.guittot@linaro.org>
Cc: Yang Jihong <yangjihong@bytedance.com>
Cc: Yujie Liu <yujie.liu@intel.com>
Cc: Zhongqiu Han <quic_zhonhan@quicinc.com>
[ Avoid potentially using 'sv' uninitialized by calling free_cpu_domain_info() only when build_cpu_domain_map() is called ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

diff --git a/tools/perf/builtin-sched.c b/tools/perf/builtin-sched.c
index c6b054b9b12a7fa574c516de2823c89248b597e3..ec9fa29196b24f5a3287fd1c6d8b86a10d45b4a9 100644 (file)
--- a/tools/perf/builtin-sched.c
+++ b/tools/perf/builtin-sched.c
@@ -4426,6 +4426,103 @@ out:
        return err;
 }
 
+static int process_synthesized_event_live(const struct perf_tool *tool __maybe_unused,
+                                         union perf_event *event,
+                                         struct perf_sample *sample __maybe_unused,
+                                         struct machine *machine __maybe_unused)
+{
+       return perf_sched__process_schedstat(tool, NULL, event);
+}
+
+static int perf_sched__schedstat_live(struct perf_sched *sched,
+                                     int argc, const char **argv)
+{
+       struct cpu_domain_map **cd_map = NULL;
+       struct target target = {};
+       u32 __maybe_unused md;
+       struct evlist *evlist;
+       u32 nr = 0, sv;
+       int reset = 0;
+       int err = 0;
+
+       signal(SIGINT, sighandler);
+       signal(SIGCHLD, sighandler);
+       signal(SIGTERM, sighandler);
+
+       evlist = evlist__new();
+       if (!evlist)
+               return -ENOMEM;
+
+       /*
+        * `perf sched schedstat` does not support workload profiling (-p pid)
+        * since /proc/schedstat file contains cpu specific data only. Hence, a
+        * profile target is either set of cpus or systemwide, never a process.
+        * Note that, although `-- <workload>` is supported, profile data are
+        * still cpu/systemwide.
+        */
+       if (cpu_list)
+               target.cpu_list = cpu_list;
+       else
+               target.system_wide = true;
+
+       if (argc) {
+               err = evlist__prepare_workload(evlist, &target, argv, false, NULL);
+               if (err)
+                       goto out;
+       }
+
+       err = evlist__create_maps(evlist, &target);
+       if (err < 0)
+               goto out;
+
+       user_requested_cpus = evlist->core.user_requested_cpus;
+
+       err = perf_event__synthesize_schedstat(&(sched->tool),
+                                              process_synthesized_event_live,
+                                              user_requested_cpus);
+       if (err < 0)
+               goto out;
+
+       err = enable_sched_schedstats(&reset);
+       if (err < 0)
+               goto out;
+
+       if (argc)
+               evlist__start_workload(evlist);
+
+       /* wait for signal */
+       pause();
+
+       if (reset) {
+               err = disable_sched_schedstat();
+               if (err < 0)
+                       goto out;
+       }
+
+       err = perf_event__synthesize_schedstat(&(sched->tool),
+                                              process_synthesized_event_live,
+                                              user_requested_cpus);
+       if (err)
+               goto out;
+
+       setup_pager();
+
+       if (list_empty(&cpu_head)) {
+               pr_err("Data is not available\n");
+               err = -1;
+               goto out;
+       }
+
+       nr = cpu__max_present_cpu().cpu;
+       cd_map = build_cpu_domain_map(&sv, &md, nr);
+       show_schedstat_data(&cpu_head, cd_map);
+       free_cpu_domain_info(cd_map, sv, nr);
+out:
+       free_schedstat(&cpu_head);
+       evlist__delete(evlist);
+       return err;
+}
+
 static bool schedstat_events_exposed(void)
 {
        /*
@@ -4751,7 +4848,7 @@ int cmd_sched(int argc, const char **argv)
                                                     stats_usage, 0);
                        return perf_sched__schedstat_report(&sched);
                }
-               usage_with_options(stats_usage, stats_options);
+               return perf_sched__schedstat_live(&sched, argc, argv);
        } else {
                usage_with_options(sched_usage, sched_options);
        }

diff --git a/tools/perf/util/header.c b/tools/perf/util/header.c
index 673d53bb2a2c59d8c08508b76dd69bd261ed95a0..9a15dd4b7640242962e30b9ad95ac63ceba01ef0 100644 (file)
--- a/tools/perf/util/header.c
+++ b/tools/perf/util/header.c
@@ -1614,8 +1614,7 @@ static int write_pmu_caps(struct feat_fd *ff,
        return 0;
 }
 
-static struct cpu_domain_map **build_cpu_domain_map(u32 *schedstat_version, u32 *max_sched_domains,
-                                                   u32 nr)
+struct cpu_domain_map **build_cpu_domain_map(u32 *schedstat_version, u32 *max_sched_domains, u32 nr)
 {
        struct domain_info *domain_info;
        struct cpu_domain_map **cd_map;

diff --git a/tools/perf/util/header.h b/tools/perf/util/header.h
index c62f3275a80f629308bc398ed2f865fda9f94fee..36cc74e2d14d259871ceb20d0fe4c6dc9513c808 100644 (file)
--- a/tools/perf/util/header.h
+++ b/tools/perf/util/header.h
@@ -211,4 +211,7 @@ char *get_cpuid_str(struct perf_cpu cpu);
 char *get_cpuid_allow_env_override(struct perf_cpu cpu);
 
 int strcmp_cpuid_str(const char *s1, const char *s2);
+
+struct cpu_domain_map **build_cpu_domain_map(u32 *schedstat_version, u32 *max_sched_domains,
+                                            u32 nr);
 #endif /* __PERF_HEADER_H */