[PATCH v6 07/13] perf stat: factor out event handling loop into dispatch_events()

From: Alexey Budankov <alexey.budankov@linux.intel.com>
To: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>, Namhyung Kim <namhyung@kernel.org>,
	Alexander Shishkin <alexander.shishkin@linux.intel.com>,
	Peter Zijlstra <peterz@infradead.org>,
	Ingo Molnar <mingo@redhat.com>, Andi Kleen <ak@linux.intel.com>,
	linux-kernel <linux-kernel@vger.kernel.org>
Subject: [PATCH v6 07/13] perf stat: factor out event handling loop into dispatch_events()
Date: Mon, 1 Jun 2020 23:10:58 +0300	[thread overview]
Message-ID: <c27103c6-fb6b-4b86-af84-0f0e8a334850@linux.intel.com> (raw)
In-Reply-To: <f8e3a714-d9b1-4647-e1d2-9981cbaa83ec@linux.intel.com>


Consolidate event dispatching loops for fork, attach and system
wide monitoring use cases into common dispatch_events() function.

Signed-off-by: Alexey Budankov <alexey.budankov@linux.intel.com>
---
 tools/perf/builtin-stat.c | 35 ++++++++++++++++++++++++-----------
 1 file changed, 24 insertions(+), 11 deletions(-)

diff --git a/tools/perf/builtin-stat.c b/tools/perf/builtin-stat.c
index edd6fdcd1c72..f2d1b8c1481d 100644
--- a/tools/perf/builtin-stat.c
+++ b/tools/perf/builtin-stat.c
@@ -504,6 +504,27 @@ static bool is_target_alive(struct target *_target,
 	return false;
 }
 
+static int dispatch_events(bool forks, int timeout, int interval, int *times, struct timespec *ts)
+{
+	bool stop = false;
+	int child = 0, status = 0;
+
+	while (1) {
+		if (forks)
+			child = waitpid(child_pid, &status, WNOHANG);
+		else
+			child = !is_target_alive(&target, evsel_list->core.threads) ? 1 : 0;
+
+		if (done || stop || child)
+			break;
+
+		nanosleep(ts, NULL);
+		stop = process_timeout(timeout, interval, times);
+	}
+
+	return status;
+}
+
 enum counter_recovery {
 	COUNTER_SKIP,
 	COUNTER_RETRY,
@@ -575,7 +596,6 @@ static int __run_perf_stat(int argc, const char **argv, int run_idx)
 	struct affinity affinity;
 	int i, cpu;
 	bool second_pass = false;
-	bool stop = false;
 
 	if (interval) {
 		ts.tv_sec  = interval / USEC_PER_MSEC;
@@ -744,12 +764,8 @@ static int __run_perf_stat(int argc, const char **argv, int run_idx)
 		perf_evlist__start_workload(evsel_list);
 		enable_counters();
 
-		if (interval || timeout) {
-			while (!stop && !waitpid(child_pid, &status, WNOHANG)) {
-				nanosleep(&ts, NULL);
-				stop = process_timeout(timeout, interval, &times);
-			}
-		}
+		if (interval || timeout)
+			status = dispatch_events(forks, timeout, interval, &times, &ts);
 		if (child_pid != -1) {
 			if (timeout)
 				kill(child_pid, SIGTERM);
@@ -766,10 +782,7 @@ static int __run_perf_stat(int argc, const char **argv, int run_idx)
 			psignal(WTERMSIG(status), argv[0]);
 	} else {
 		enable_counters();
-		while (!done && !stop && is_target_alive(&target, evsel_list->core.threads)) {
-			nanosleep(&ts, NULL);
-			stop = process_timeout(timeout, interval, &times);
-		}
+		dispatch_events(forks, timeout, interval, &times, &ts);
 	}
 
 	disable_counters();
-- 
2.24.1

