[tip:perf/core] perf stat: clarify unsupported events from uncounted events

From: tip-bot for David Ahern
Date: Fri Jun 03 2011 - 09:38:18 EST


Commit-ID: 2cee77c4505fc581f41b44e18ffc0953b67a414c
Gitweb: http://git.kernel.org/tip/2cee77c4505fc581f41b44e18ffc0953b67a414c
Author: David Ahern <dsahern@xxxxxxxxx>
AuthorDate: Mon, 30 May 2011 08:55:59 -0600
Committer: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
CommitDate: Thu, 2 Jun 2011 13:26:15 -0300

perf stat: clarify unsupported events from uncounted events

perf stat continues running even if the event list contains counters
that are not supported. The resulting output then contains <not counted>
for those events which gets confusing as to which events are supported,
but not counted and which are not supported.

Before:

perf stat -ddd -- sleep 1

Performance counter stats for 'sleep 1':

0.571283 task-clock # 0.001 CPUs utilized
1 context-switches # 0.002 M/sec
0 CPU-migrations # 0.000 M/sec
157 page-faults # 0.275 M/sec
1,037,707 cycles # 1.816 GHz
<not counted> stalled-cycles-frontend
<not counted> stalled-cycles-backend
654,499 instructions # 0.63 insns per cycle
136,129 branches # 238.286 M/sec
<not counted> branch-misses
<not counted> L1-dcache-loads
<not counted> L1-dcache-load-misses
<not counted> LLC-loads
<not counted> LLC-load-misses
<not counted> L1-icache-loads
<not counted> L1-icache-load-misses
<not counted> dTLB-loads
<not counted> dTLB-load-misses
<not counted> iTLB-loads
<not counted> iTLB-load-misses
<not counted> L1-dcache-prefetches
<not counted> L1-dcache-prefetch-misses

1.001004836 seconds time elapsed

After:

perf stat -ddd -- sleep 1

Performance counter stats for 'sleep 1':

1.350326 task-clock # 0.001 CPUs utilized
2 context-switches # 0.001 M/sec
0 CPU-migrations # 0.000 M/sec
157 page-faults # 0.116 M/sec
11,986 cycles # 0.009 GHz
<not supported> stalled-cycles-frontend
<not supported> stalled-cycles-backend
496,986 instructions # 41.46 insns per cycle
138,065 branches # 102.246 M/sec
7,245 branch-misses # 5.25% of all branches
<not counted> L1-dcache-loads
<not counted> L1-dcache-load-misses
<not counted> LLC-loads
<not counted> LLC-load-misses
<not counted> L1-icache-loads
<not counted> L1-icache-load-misses
<not counted> dTLB-loads
<not counted> dTLB-load-misses
<not counted> iTLB-loads
<not counted> iTLB-load-misses
<not counted> L1-dcache-prefetches
<not supported> L1-dcache-prefetch-misses

1.002397333 seconds time elapsed

v1->v2:
changed supported type from int to bool

v2->v3
fixed vertical alignment of new struct element

Cc: Frederic Weisbecker <fweisbec@xxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxx>
Cc: Paul Mackerras <paulus@xxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Link: http://lkml.kernel.org/r/1306767359-13221-1-git-send-email-dsahern@xxxxxxxxx
Signed-off-by: David Ahern <dsahern@xxxxxxxxx>
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
---
tools/perf/builtin-stat.c | 9 +++++++--
tools/perf/util/evsel.h | 1 +
2 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/tools/perf/builtin-stat.c b/tools/perf/builtin-stat.c
index a9f0671..784ed6d 100644
--- a/tools/perf/builtin-stat.c
+++ b/tools/perf/builtin-stat.c
@@ -61,6 +61,8 @@
#include <locale.h>

#define DEFAULT_SEPARATOR " "
+#define CNTR_NOT_SUPPORTED "<not supported>"
+#define CNTR_NOT_COUNTED "<not counted>"

static struct perf_event_attr default_attrs[] = {

@@ -448,6 +450,7 @@ static int run_perf_stat(int argc __used, const char **argv)
if (verbose)
ui__warning("%s event is not supported by the kernel.\n",
event_name(counter));
+ counter->supported = false;
continue;
}

@@ -466,6 +469,7 @@ static int run_perf_stat(int argc __used, const char **argv)
die("Not all events could be opened.\n");
return -1;
}
+ counter->supported = true;
}

if (perf_evlist__set_filters(evsel_list)) {
@@ -861,7 +865,7 @@ static void print_counter_aggr(struct perf_evsel *counter)
if (scaled == -1) {
fprintf(stderr, "%*s%s%*s",
csv_output ? 0 : 18,
- "<not counted>",
+ counter->supported ? CNTR_NOT_COUNTED : CNTR_NOT_SUPPORTED,
csv_sep,
csv_output ? 0 : -24,
event_name(counter));
@@ -914,7 +918,8 @@ static void print_counter(struct perf_evsel *counter)
csv_output ? 0 : -4,
evsel_list->cpus->map[cpu], csv_sep,
csv_output ? 0 : 18,
- "<not counted>", csv_sep,
+ counter->supported ? CNTR_NOT_COUNTED : CNTR_NOT_SUPPORTED,
+ csv_sep,
csv_output ? 0 : -24,
event_name(counter));

diff --git a/tools/perf/util/evsel.h b/tools/perf/util/evsel.h
index 7e9366e..e9a3155 100644
--- a/tools/perf/util/evsel.h
+++ b/tools/perf/util/evsel.h
@@ -61,6 +61,7 @@ struct perf_evsel {
off_t id_offset;
};
struct cgroup_sel *cgrp;
+ bool supported;
};

struct cpu_map;
--
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