[PATCH 12/14] perf test: Allow infinite named_thread loops

[James Clark]

The following test will want this to run forever, so add support by
treating 0 loops as infinite.

Convert i and named_threads_work to be unsigned to avoid undefined
signed overflow behavior in infinite loop mode.

Signed-off-by: James Clark <james.clark at linaro.org>
---
 tools/perf/Documentation/perf-test.txt     | 2 +-
 tools/perf/tests/workloads/named_threads.c | 7 ++++---
 2 files changed, 5 insertions(+), 4 deletions(-)

diff --git a/tools/perf/Documentation/perf-test.txt b/tools/perf/Documentation/perf-test.txt
index 859df74e62ef..dca8972fec8d 100644
--- a/tools/perf/Documentation/perf-test.txt
+++ b/tools/perf/Documentation/perf-test.txt
@@ -68,7 +68,7 @@ OPTIONS
 		nrloops: brstack, context_switch_loop
 
 	'named_threads' accepts the number of threads and the number of loops to
-	do in each thread.
+	do in each thread. Use 0 for an infinite loop.
 
 	The datasym, landlock, deterministic and callchain workloads don't accept
 	any.
diff --git a/tools/perf/tests/workloads/named_threads.c b/tools/perf/tests/workloads/named_threads.c
index d051d41a3cfe..6672c2f77684 100644
--- a/tools/perf/tests/workloads/named_threads.c
+++ b/tools/perf/tests/workloads/named_threads.c
@@ -11,7 +11,7 @@
 #define MAX_THREADS 25
 
 static int iterations = 500;
-int named_threads_work = 1234;
+unsigned int named_threads_work = 1234;
 
 typedef void *(*thread_fn_t)(void *);
 
@@ -19,7 +19,8 @@ typedef void *(*thread_fn_t)(void *);
 noinline void *named_threads_thread##n(void *arg __maybe_unused)	\
 {									\
 	pthread_setname_np(pthread_self(), "thread" #n);		\
-	for (int i = 0; i < iterations; i++)				\
+	for (unsigned int i = 0;					\
+	     i < (unsigned int) iterations || iterations == 0; i++)	\
 		named_threads_work += 3;				\
 									\
 	return NULL;							\
@@ -65,7 +66,7 @@ static thread_fn_t thread_fns[MAX_THREADS] = {
 
 /*
  * Creates argv[0] threads that run a unique function named "thread[x]" which performs
- * a multiplication in a loop for argv[1] loops.
+ * a multiplication in a loop for argv[1] loops (use 0 for infinite loop).
  */
 static int named_threads(int argc, const char **argv)
 {

-- 
2.43.0