1 files changed, 106 insertions, 0 deletions
diff --git a/tools/testing/selftests/futex/functional/futex_requeue.c b/tools/testing/selftests/futex/functional/futex_requeue.c
new file mode 100644
index 000000000000..35d4be23db5d
--- /dev/null
+++ b/tools/testing/selftests/futex/functional/futex_requeue.c
@@ -0,0 +1,106 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright Collabora Ltd., 2021
+ *
+ * futex cmp requeue test by André Almeida <andrealmeid@collabora.com>
+ */
+
+#include <pthread.h>
+#include <limits.h>
+
+#include "futextest.h"
+#include "kselftest_harness.h"
+
+#define timeout_ns  30000000
+#define WAKE_WAIT_US 10000
+
+volatile futex_t *f1;
+
+void *waiterfn(void *arg)
+{
+	struct timespec to;
+
+	to.tv_sec = 0;
+	to.tv_nsec = timeout_ns;
+
+	if (futex_wait(f1, *f1, &to, 0))
+		printf("waiter failed errno %d\n", errno);
+
+	return NULL;
+}
+
+TEST(requeue_single)
+{
+	volatile futex_t _f1 = 0;
+	volatile futex_t f2 = 0;
+	pthread_t waiter[10];
+	int res;
+
+	f1 = &_f1;
+
+	/*
+	 * Requeue a waiter from f1 to f2, and wake f2.
+	 */
+	if (pthread_create(&waiter[0], NULL, waiterfn, NULL))
+		ksft_exit_fail_msg("pthread_create failed\n");
+
+	usleep(WAKE_WAIT_US);
+
+	ksft_print_dbg_msg("Requeuing 1 futex from f1 to f2\n");
+	res = futex_cmp_requeue(f1, 0, &f2, 0, 1, 0);
+	if (res != 1)
+		ksft_test_result_fail("futex_requeue simple returned: %d %s\n",
+				      res ? errno : res,
+				      res ? strerror(errno) : "");
+
+	ksft_print_dbg_msg("Waking 1 futex at f2\n");
+	res = futex_wake(&f2, 1, 0);
+	if (res != 1) {
+		ksft_test_result_fail("futex_requeue simple returned: %d %s\n",
+				      res ? errno : res,
+				      res ? strerror(errno) : "");
+	} else {
+		ksft_test_result_pass("futex_requeue simple succeeds\n");
+	}
+}
+
+TEST(requeue_multiple)
+{
+	volatile futex_t _f1 = 0;
+	volatile futex_t f2 = 0;
+	pthread_t waiter[10];
+	int res, i;
+
+	f1 = &_f1;
+
+	/*
+	 * Create 10 waiters at f1. At futex_requeue, wake 3 and requeue 7.
+	 * At futex_wake, wake INT_MAX (should be exactly 7).
+	 */
+	for (i = 0; i < 10; i++) {
+		if (pthread_create(&waiter[i], NULL, waiterfn, NULL))
+			ksft_exit_fail_msg("pthread_create failed\n");
+	}
+
+	usleep(WAKE_WAIT_US);
+
+	ksft_print_dbg_msg("Waking 3 futexes at f1 and requeuing 7 futexes from f1 to f2\n");
+	res = futex_cmp_requeue(f1, 0, &f2, 3, 7, 0);
+	if (res != 10) {
+		ksft_test_result_fail("futex_requeue many returned: %d %s\n",
+				      res ? errno : res,
+				      res ? strerror(errno) : "");
+	}
+
+	ksft_print_dbg_msg("Waking INT_MAX futexes at f2\n");
+	res = futex_wake(&f2, INT_MAX, 0);
+	if (res != 7) {
+		ksft_test_result_fail("futex_requeue many returned: %d %s\n",
+				      res ? errno : res,
+				      res ? strerror(errno) : "");
+	} else {
+		ksft_test_result_pass("futex_requeue many succeeds\n");
+	}
+}
+
+TEST_HARNESS_MAIN