selftests: futex: Test sys_futex_waitv() wouldblock

Test if futex_waitv() returns -EWOULDBLOCK correctly when the expected
value is different from the actual value for a waiter.

Signed-off-by: André Almeida <[e-mail]>
Signed-off-by: Peter Zijlstra (Intel) <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]

tools/testing/selftests/futex/functional/futex_wait_wouldblock.c

···
 #include <string.h>
 #include <time.h>
 #include "futextest.h"
+#include "futex2test.h"
 #include "logging.h"
 
 #define TEST_NAME "futex-wait-wouldblock"
···
 	futex_t f1 = FUTEX_INITIALIZER;
 	int res, ret = RET_PASS;
 	int c;
+	struct futex_waitv waitv = {
+			.uaddr = (uintptr_t)&f1,
+			.val = f1+1,
+			.flags = FUTEX_32,
+			.__reserved = 0
+		};
 
 	while ((c = getopt(argc, argv, "cht:v:")) != -1) {
 		switch (c) {
···
 	}
 
 	ksft_print_header();
-	ksft_set_plan(1);
+	ksft_set_plan(2);
 	ksft_print_msg("%s: Test the unexpected futex value in FUTEX_WAIT\n",
 	       basename(argv[0]));
 
 	info("Calling futex_wait on f1: %u @ %p with val=%u\n", f1, &f1, f1+1);
 	res = futex_wait(&f1, f1+1, &to, FUTEX_PRIVATE_FLAG);
 	if (!res || errno != EWOULDBLOCK) {
-		fail("futex_wait returned: %d %s\n",
-		     res ? errno : res, res ? strerror(errno) : "");
+		ksft_test_result_fail("futex_wait returned: %d %s\n",
+				      res ? errno : res,
+				      res ? strerror(errno) : "");
 		ret = RET_FAIL;
+	} else {
+		ksft_test_result_pass("futex_wait\n");
 	}
 
-	print_result(TEST_NAME, ret);
+	if (clock_gettime(CLOCK_MONOTONIC, &to)) {
+		error("clock_gettime failed\n", errno);
+		return errno;
+	}
+
+	to.tv_nsec += timeout_ns;
+
+	if (to.tv_nsec >= 1000000000) {
+		to.tv_sec++;
+		to.tv_nsec -= 1000000000;
+	}
+
+	info("Calling futex_waitv on f1: %u @ %p with val=%u\n", f1, &f1, f1+1);
+	res = futex_waitv(&waitv, 1, 0, &to, CLOCK_MONOTONIC);
+	if (!res || errno != EWOULDBLOCK) {
+		ksft_test_result_pass("futex_waitv returned: %d %s\n",
+				      res ? errno : res,
+				      res ? strerror(errno) : "");
+		ret = RET_FAIL;
+	} else {
+		ksft_test_result_pass("futex_waitv\n");
+	}
+
+	ksft_print_cnts();
 	return ret;
 }