perf sched: Add max delay time snapshot
When we have a maximum latency reported for a task, we need a
convenient way to find the matching location to the raw traces
or to perf sched map that shows where the task has been
eventually scheduled in. This gives a pointer to retrieve the
events that occured during this max latency.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Reviewed-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <1260391208-6808-1-git-send-regression-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/tools/perf/builtin-sched.c b/tools/perf/builtin-sched.c
index b12b23a..7cca7c1 100644
--- a/tools/perf/builtin-sched.c
+++ b/tools/perf/builtin-sched.c
@@ -140,6 +140,7 @@
struct thread *thread;
struct rb_node node;
u64 max_lat;
+ u64 max_lat_at;
u64 total_lat;
u64 nb_atoms;
u64 total_runtime;
@@ -1013,8 +1014,10 @@
delta = atom->sched_in_time - atom->wake_up_time;
atoms->total_lat += delta;
- if (delta > atoms->max_lat)
+ if (delta > atoms->max_lat) {
atoms->max_lat = delta;
+ atoms->max_lat_at = timestamp;
+ }
atoms->nb_atoms++;
}
@@ -1210,10 +1213,11 @@
avg = work_list->total_lat / work_list->nb_atoms;
- printf("|%11.3f ms |%9llu | avg:%9.3f ms | max:%9.3f ms |\n",
+ printf("|%11.3f ms |%9llu | avg:%9.3f ms | max:%9.3f ms | max at: %9.6f s\n",
(double)work_list->total_runtime / 1e6,
work_list->nb_atoms, (double)avg / 1e6,
- (double)work_list->max_lat / 1e6);
+ (double)work_list->max_lat / 1e6,
+ (double)work_list->max_lat_at / 1e9);
}
static int pid_cmp(struct work_atoms *l, struct work_atoms *r)
@@ -1704,9 +1708,9 @@
read_events();
sort_lat();
- printf("\n -----------------------------------------------------------------------------------------\n");
- printf(" Task | Runtime ms | Switches | Average delay ms | Maximum delay ms |\n");
- printf(" -----------------------------------------------------------------------------------------\n");
+ printf("\n ---------------------------------------------------------------------------------------------------------------\n");
+ printf(" Task | Runtime ms | Switches | Average delay ms | Maximum delay ms | Maximum delay at |\n");
+ printf(" ---------------------------------------------------------------------------------------------------------------\n");
next = rb_first(&sorted_atom_root);