[PATCH/RFC 14/16] perf top: Separate struct perf_top_stats

[Namhyung Kim <namhyung@kernel.org>]

The perf top maintains various stats regarding samples.  Separate out
those stats so that it can be updated concurrently.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
---
 tools/perf/builtin-top.c | 36 ++++++++++++++++++++++++++++--------
 tools/perf/util/top.c    | 18 ++++++++----------
 tools/perf/util/top.h    | 12 ++++++++----
 3 files changed, 44 insertions(+), 22 deletions(-)

diff --git a/tools/perf/builtin-top.c b/tools/perf/builtin-top.c
index 5987986b5203..f3ab46b234b6 100644
--- a/tools/perf/builtin-top.c
+++ b/tools/perf/builtin-top.c
@@ -902,8 +902,26 @@ struct reader_arg {
 	int			idx;
 	struct perf_top		*top;
 	struct hists		*hists;
+	struct perf_top_stats	stats;
 };
 
+static void perf_top_stats__add(struct perf_top_stats *dst,
+				struct perf_top_stats *src)
+{
+	static pthread_mutex_t stats_lock = PTHREAD_MUTEX_INITIALIZER;
+
+	pthread_mutex_lock(&stats_lock);
+
+	dst->samples              += src->samples;
+	dst->exact_samples        += src->exact_samples;
+	dst->kernel_samples       += src->kernel_samples;
+	dst->us_samples           += src->us_samples;
+	dst->guest_kernel_samples += src->guest_kernel_samples;
+	dst->guest_us_samples     += src->guest_us_samples;
+
+	pthread_mutex_unlock(&stats_lock);
+}
+
 static void perf_event__process_sample(struct reader_arg *rarg,
 				       const union perf_event *event,
 				       struct perf_evsel *evsel,
@@ -938,7 +956,7 @@ static void perf_event__process_sample(struct reader_arg *rarg,
 	}
 
 	if (event->header.misc & PERF_RECORD_MISC_EXACT_IP)
-		top->exact_samples++;
+		rarg->stats.exact_samples++;
 
 	if (perf_event__preprocess_sample(event, machine, &al, sample) < 0)
 		return;
@@ -1000,28 +1018,28 @@ static void perf_top__mmap_read(struct reader_arg *rarg)
 		origin = event->header.misc & PERF_RECORD_MISC_CPUMODE_MASK;
 
 		if (event->header.type == PERF_RECORD_SAMPLE)
-			++top->samples;
+			++rarg->stats.samples;
 
 		switch (origin) {
 		case PERF_RECORD_MISC_USER:
-			++top->us_samples;
+			++rarg->stats.us_samples;
 			if (top->hide_user_symbols)
 				goto next_event;
 			machine = &session->machines.host;
 			break;
 		case PERF_RECORD_MISC_KERNEL:
-			++top->kernel_samples;
+			++rarg->stats.kernel_samples;
 			if (top->hide_kernel_symbols)
 				goto next_event;
 			machine = &session->machines.host;
 			break;
 		case PERF_RECORD_MISC_GUEST_KERNEL:
-			++top->guest_kernel_samples;
+			++rarg->stats.guest_kernel_samples;
 			machine = perf_session__find_machine(session,
 							     sample.pid);
 			break;
 		case PERF_RECORD_MISC_GUEST_USER:
-			++top->guest_us_samples;
+			++rarg->stats.guest_us_samples;
 			/*
 			 * TODO: we don't process guest user from host side
 			 * except simple counting.
@@ -1065,12 +1083,14 @@ static void *mmap_read_worker(void *arg)
 	}
 
 	while (!done) {
-		u64 hits = top->samples;
+		u64 hits = rarg->stats.samples;
 
 		perf_top__mmap_read(rarg);
 
-		if (hits == top->samples)
+		if (hits == rarg->stats.samples)
 			perf_evlist__poll(top->evlist, 100);
+		else
+			perf_top_stats__add(&top->stats, &rarg->stats);
 	}
 	return NULL;
 }
diff --git a/tools/perf/util/top.c b/tools/perf/util/top.c
index 8e517def925b..95d6bba1a2a0 100644
--- a/tools/perf/util/top.c
+++ b/tools/perf/util/top.c
@@ -30,10 +30,10 @@ size_t perf_top__header_snprintf(struct perf_top *top, char *bf, size_t size)
 	struct target *target = &opts->target;
 	size_t ret = 0;
 
-	if (top->samples) {
-		samples_per_sec = top->samples / top->delay_secs;
-		ksamples_per_sec = top->kernel_samples / top->delay_secs;
-		esamples_percent = (100.0 * top->exact_samples) / top->samples;
+	if (top->stats.samples) {
+		samples_per_sec = top->stats.samples / top->delay_secs;
+		ksamples_per_sec = top->stats.kernel_samples / top->delay_secs;
+		esamples_percent = (100.0 * top->stats.exact_samples) / top->stats.samples;
 	} else {
 		samples_per_sec = ksamples_per_sec = esamples_percent = 0.0;
 	}
@@ -49,9 +49,9 @@ size_t perf_top__header_snprintf(struct perf_top *top, char *bf, size_t size)
 			       "  exact: %4.1f%% [", samples_per_sec,
 			       ksamples_percent, esamples_percent);
 	} else {
-		float us_samples_per_sec = top->us_samples / top->delay_secs;
-		float guest_kernel_samples_per_sec = top->guest_kernel_samples / top->delay_secs;
-		float guest_us_samples_per_sec = top->guest_us_samples / top->delay_secs;
+		float us_samples_per_sec = top->stats.us_samples / top->delay_secs;
+		float guest_kernel_samples_per_sec = top->stats.guest_kernel_samples / top->delay_secs;
+		float guest_us_samples_per_sec = top->stats.guest_us_samples / top->delay_secs;
 
 		ret = SNPRINTF(bf, size,
 			       "   PerfTop:%8.0f irqs/sec  kernel:%4.1f%% us:%4.1f%%"
@@ -111,7 +111,5 @@ size_t perf_top__header_snprintf(struct perf_top *top, char *bf, size_t size)
 
 void perf_top__reset_sample_counters(struct perf_top *top)
 {
-	top->samples = top->us_samples = top->kernel_samples =
-	top->exact_samples = top->guest_kernel_samples =
-	top->guest_us_samples = 0;
+	memset(&top->stats, 0, sizeof(top->stats));
 }
diff --git a/tools/perf/util/top.h b/tools/perf/util/top.h
index c56a00cff5b4..55eb5aebae59 100644
--- a/tools/perf/util/top.h
+++ b/tools/perf/util/top.h
@@ -11,18 +11,22 @@ struct perf_evlist;
 struct perf_evsel;
 struct perf_session;
 
+struct perf_top_stats {
+	u64		   samples;
+	u64		   exact_samples;
+	u64		   kernel_samples, us_samples;
+	u64		   guest_kernel_samples, guest_us_samples;
+};
+
 struct perf_top {
 	struct perf_tool   tool;
 	struct perf_evlist *evlist;
 	struct record_opts record_opts;
+	struct perf_top_stats stats;
 	/*
 	 * Symbols will be added here in perf_event__process_sample and will
 	 * get out after decayed.
 	 */
-	u64		   samples;
-	u64		   kernel_samples, us_samples;
-	u64		   exact_samples;
-	u64		   guest_us_samples, guest_kernel_samples;
 	int		   print_entries, count_filter, delay_secs;
 	int		   max_stack;
 	bool		   hide_kernel_symbols, hide_user_symbols, zero;
-- 
2.6.2