[tip:perf/pebs] perf-top: Show the percentage of successfull PEBS-fixups

tip-bot for Peter Zijlstra
2010-03-10T13:20:25Z

Commit-ID: 1676b8a077c352085d52578fb4f29350b58b6e74
Gitweb: http://git.kernel.org/tip/1676b8a077c352085d52578fb4f29350b58b6e74
Author: Peter Zijlstra <a.p.zijlstra@chello.nl>
AuthorDate: Thu, 4 Mar 2010 14:19:36 +0100
Committer: Ingo Molnar <mingo@elte.hu>
CommitDate: Wed, 10 Mar 2010 13:23:33 +0100

perf-top: Show the percentage of successfull PEBS-fixups

Use the PERF_RECORD_MISC_EXACT information to measure the success rate of
the PEBS fix-up.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: paulus@samba.org
Cc: eranian@google.com
Cc: robert.richter@amd.com
Cc: fweisbec@gmail.com
LKML-Reference: <20100304140100.694233760@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
---
tools/perf/builtin-top.c | 12 +++++++++---
1 files changed, 9 insertions(+), 3 deletions(-)

diff --git a/tools/perf/builtin-top.c b/tools/perf/builtin-top.c
index 31f2e59..c051833 100644
--- a/tools/perf/builtin-top.c
+++ b/tools/perf/builtin-top.c
@@ -410,6 +410,7 @@ static double sym_weight(const struct sym_entry *sym)

static long samples;
static long userspace_samples;
+static long exact_samples;
static const char CONSOLE_CLEAR[] = "^[[H^[[2J";

static void __list_insert_active_sym(struct sym_entry *syme)
@@ -450,6 +451,7 @@ static void print_sym_table(void)
int counter, snap = !display_weighted ? sym_counter : 0;
float samples_per_sec = samples/delay_secs;
float ksamples_per_sec = (samples-userspace_samples)/delay_secs;
+ float esamples_percent = (100.0*exact_samples)/samples;
float sum_ksamples = 0.0;
struct sym_entry *syme, *n;
struct rb_root tmp = RB_ROOT;
@@ -457,7 +459,7 @@ static void print_sym_table(void)
int sym_width = 0, dso_width = 0, max_dso_width;
const int win_width = winsize.ws_col - 1;

- samples = userspace_samples = 0;
+ samples = userspace_samples = exact_samples = 0;

/* Sort the active symbols */
pthread_mutex_lock(&active_symbols_lock);
@@ -488,9 +490,10 @@ static void print_sym_table(void)
puts(CONSOLE_CLEAR);

printf("%-*.*s\n", win_width, win_width, graph_dotted_line);
- printf( " PerfTop:%8.0f irqs/sec kernel:%4.1f%% [",
+ printf( " PerfTop:%8.0f irqs/sec kernel:%4.1f%% exact: %4.1f%% [",
samples_per_sec,
- 100.0 - (100.0*((samples_per_sec-ksamples_per_sec)/samples_per_sec)));
+ 100.0 - (100.0*((samples_per_sec-ksamples_per_sec)/samples_per_sec)),
+ esamples_percent);

if (nr_counters == 1 || !display_weighted) {
printf("%Ld", (u64)attrs[0].sample_period);
@@ -954,6 +957,9 @@ static void event__process_sample(const event_t *self,
return;
}

+ if (self->header.misc & PERF_RECORD_MISC_EXACT)
+ exact_samples++;
+
if (event__preprocess_sample(self, session, &al, symbol_filter) < 0 ||
al.filtered)
return;