[PATCH 03/12] perf test: Add 'thloop' test workload

[Namhyung Kim]

The thloop is similar to noploop but runs in two threads.  This is
needed to verify perf record --per-thread to handle multi-threaded
programs properly.

  $ perf test -w thloop

It also takes an optional argument to specify runtime in seconds
(default: 1).

Signed-off-by: Namhyung Kim <namhyung@xxxxxxxxxx>
---
 tools/perf/tests/builtin-test.c     |  1 +
 tools/perf/tests/tests.h            |  1 +
 tools/perf/tests/workloads/Build    |  1 +
 tools/perf/tests/workloads/thloop.c | 53 +++++++++++++++++++++++++++++
 4 files changed, 56 insertions(+)
 create mode 100644 tools/perf/tests/workloads/thloop.c

diff --git a/tools/perf/tests/builtin-test.c b/tools/perf/tests/builtin-test.c
index ce641ccfcf81..161f38476e77 100644
--- a/tools/perf/tests/builtin-test.c
+++ b/tools/perf/tests/builtin-test.c
@@ -120,6 +120,7 @@ static struct test_suite **tests[] = {
 
 static struct test_workload *workloads[] = {
 	&workload__noploop,
+	&workload__thloop,
 };
 
 static int num_subtests(const struct test_suite *t)
diff --git a/tools/perf/tests/tests.h b/tools/perf/tests/tests.h
index d315d0d6fc97..e6edfeeadaeb 100644
--- a/tools/perf/tests/tests.h
+++ b/tools/perf/tests/tests.h
@@ -201,5 +201,6 @@ struct test_workload workload__##work = {	\
 
 /* The list of test workloads */
 DECLARE_WORKLOAD(noploop);
+DECLARE_WORKLOAD(thloop);
 
 #endif /* TESTS_H */
diff --git a/tools/perf/tests/workloads/Build b/tools/perf/tests/workloads/Build
index f98e968d4633..b8964b1099c0 100644
--- a/tools/perf/tests/workloads/Build
+++ b/tools/perf/tests/workloads/Build
@@ -1,3 +1,4 @@
 # SPDX-License-Identifier: GPL-2.0
 
 perf-y += noploop.o
+perf-y += thloop.o
diff --git a/tools/perf/tests/workloads/thloop.c b/tools/perf/tests/workloads/thloop.c
new file mode 100644
index 000000000000..29193b75717e
--- /dev/null
+++ b/tools/perf/tests/workloads/thloop.c
@@ -0,0 +1,53 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#include <pthread.h>
+#include <stdlib.h>
+#include <signal.h>
+#include <unistd.h>
+#include <linux/compiler.h>
+#include "../tests.h"
+
+static volatile sig_atomic_t done;
+static volatile unsigned count;
+
+/* We want to check this symbol in perf report */
+noinline void test_loop(void);
+
+static void sighandler(int sig __maybe_unused)
+{
+	done = 1;
+}
+
+noinline void test_loop(void)
+{
+	while (!done)
+		count++;
+}
+
+static void *thfunc(void *arg)
+{
+	void (*loop_fn)(void) = arg;
+
+	loop_fn();
+	return NULL;
+}
+
+static int thloop(int argc, const char **argv)
+{
+	int sec = 1;
+	pthread_t th;
+
+	if (argc > 0)
+		sec = atoi(argv[0]);
+
+	signal(SIGINT, sighandler);
+	signal(SIGALRM, sighandler);
+	alarm(sec);
+
+	pthread_create(&th, NULL, thfunc, test_loop);
+	test_loop();
+	pthread_join(th, NULL);
+
+	return 0;
+}
+
+DEFINE_WORKLOAD(thloop);
-- 
2.38.1.584.g0f3c55d4c2-goog