diff options
Diffstat (limited to 'tools/testing/selftests/futex/functional/futex_wait_timeout.c')
| -rw-r--r-- | tools/testing/selftests/futex/functional/futex_wait_timeout.c | 206 |
1 files changed, 206 insertions, 0 deletions
diff --git a/tools/testing/selftests/futex/functional/futex_wait_timeout.c b/tools/testing/selftests/futex/functional/futex_wait_timeout.c new file mode 100644 index 000000000..d183f8783 --- /dev/null +++ b/tools/testing/selftests/futex/functional/futex_wait_timeout.c @@ -0,0 +1,206 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/****************************************************************************** + * + * Copyright © International Business Machines Corp., 2009 + * + * DESCRIPTION + * Block on a futex and wait for timeout. + * + * AUTHOR + * Darren Hart <dvhart@linux.intel.com> + * + * HISTORY + * 2009-Nov-6: Initial version by Darren Hart <dvhart@linux.intel.com> + * 2021-Apr-26: More test cases by André Almeida <andrealmeid@collabora.com> + * + *****************************************************************************/ + +#include <pthread.h> +#include "futextest.h" +#include "futex2test.h" +#include "logging.h" + +#define TEST_NAME "futex-wait-timeout" + +static long timeout_ns = 100000; /* 100us default timeout */ +static futex_t futex_pi; +static pthread_barrier_t barrier; + +void usage(char *prog) +{ + printf("Usage: %s\n", prog); + printf(" -c Use color\n"); + printf(" -h Display this help message\n"); + printf(" -t N Timeout in nanoseconds (default: 100,000)\n"); + printf(" -v L Verbosity level: %d=QUIET %d=CRITICAL %d=INFO\n", + VQUIET, VCRITICAL, VINFO); +} + +/* + * Get a PI lock and hold it forever, so the main thread lock_pi will block + * and we can test the timeout + */ +void *get_pi_lock(void *arg) +{ + int ret; + volatile futex_t lock = 0; + + ret = futex_lock_pi(&futex_pi, NULL, 0, 0); + if (ret != 0) + error("futex_lock_pi failed\n", ret); + + pthread_barrier_wait(&barrier); + + /* Blocks forever */ + ret = futex_wait(&lock, 0, NULL, 0); + error("futex_wait failed\n", ret); + + return NULL; +} + +/* + * Check if the function returned the expected error + */ +static void test_timeout(int res, int *ret, char *test_name, int err) +{ + if (!res || errno != err) { + ksft_test_result_fail("%s returned %d\n", test_name, + res < 0 ? errno : res); + *ret = RET_FAIL; + } else { + ksft_test_result_pass("%s succeeds\n", test_name); + } +} + +/* + * Calculate absolute timeout and correct overflow + */ +static int futex_get_abs_timeout(clockid_t clockid, struct timespec *to, + long timeout_ns) +{ + if (clock_gettime(clockid, 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; + } + + return 0; +} + +int main(int argc, char *argv[]) +{ + futex_t f1 = FUTEX_INITIALIZER; + int res, ret = RET_PASS; + struct timespec to; + pthread_t thread; + int c; + struct futex_waitv waitv = { + .uaddr = (uintptr_t)&f1, + .val = f1, + .flags = FUTEX_32, + .__reserved = 0 + }; + + while ((c = getopt(argc, argv, "cht:v:")) != -1) { + switch (c) { + case 'c': + log_color(1); + break; + case 'h': + usage(basename(argv[0])); + exit(0); + case 't': + timeout_ns = atoi(optarg); + break; + case 'v': + log_verbosity(atoi(optarg)); + break; + default: + usage(basename(argv[0])); + exit(1); + } + } + + ksft_print_header(); + ksft_set_plan(9); + ksft_print_msg("%s: Block on a futex and wait for timeout\n", + basename(argv[0])); + ksft_print_msg("\tArguments: timeout=%ldns\n", timeout_ns); + + pthread_barrier_init(&barrier, NULL, 2); + pthread_create(&thread, NULL, get_pi_lock, NULL); + + /* initialize relative timeout */ + to.tv_sec = 0; + to.tv_nsec = timeout_ns; + + res = futex_wait(&f1, f1, &to, 0); + test_timeout(res, &ret, "futex_wait relative", ETIMEDOUT); + + /* FUTEX_WAIT_BITSET with CLOCK_REALTIME */ + if (futex_get_abs_timeout(CLOCK_REALTIME, &to, timeout_ns)) + return RET_FAIL; + res = futex_wait_bitset(&f1, f1, &to, 1, FUTEX_CLOCK_REALTIME); + test_timeout(res, &ret, "futex_wait_bitset realtime", ETIMEDOUT); + + /* FUTEX_WAIT_BITSET with CLOCK_MONOTONIC */ + if (futex_get_abs_timeout(CLOCK_MONOTONIC, &to, timeout_ns)) + return RET_FAIL; + res = futex_wait_bitset(&f1, f1, &to, 1, 0); + test_timeout(res, &ret, "futex_wait_bitset monotonic", ETIMEDOUT); + + /* FUTEX_WAIT_REQUEUE_PI with CLOCK_REALTIME */ + if (futex_get_abs_timeout(CLOCK_REALTIME, &to, timeout_ns)) + return RET_FAIL; + res = futex_wait_requeue_pi(&f1, f1, &futex_pi, &to, FUTEX_CLOCK_REALTIME); + test_timeout(res, &ret, "futex_wait_requeue_pi realtime", ETIMEDOUT); + + /* FUTEX_WAIT_REQUEUE_PI with CLOCK_MONOTONIC */ + if (futex_get_abs_timeout(CLOCK_MONOTONIC, &to, timeout_ns)) + return RET_FAIL; + res = futex_wait_requeue_pi(&f1, f1, &futex_pi, &to, 0); + test_timeout(res, &ret, "futex_wait_requeue_pi monotonic", ETIMEDOUT); + + /* Wait until the other thread calls futex_lock_pi() */ + pthread_barrier_wait(&barrier); + pthread_barrier_destroy(&barrier); + /* + * FUTEX_LOCK_PI with CLOCK_REALTIME + * Due to historical reasons, FUTEX_LOCK_PI supports only realtime + * clock, but requires the caller to not set CLOCK_REALTIME flag. + * + * If you call FUTEX_LOCK_PI with a monotonic clock, it'll be + * interpreted as a realtime clock, and (unless you mess your machine's + * time or your time machine) the monotonic clock value is always + * smaller than realtime and the syscall will timeout immediately. + */ + if (futex_get_abs_timeout(CLOCK_REALTIME, &to, timeout_ns)) + return RET_FAIL; + res = futex_lock_pi(&futex_pi, &to, 0, 0); + test_timeout(res, &ret, "futex_lock_pi realtime", ETIMEDOUT); + + /* Test operations that don't support FUTEX_CLOCK_REALTIME */ + res = futex_lock_pi(&futex_pi, NULL, 0, FUTEX_CLOCK_REALTIME); + test_timeout(res, &ret, "futex_lock_pi invalid timeout flag", ENOSYS); + + /* futex_waitv with CLOCK_MONOTONIC */ + if (futex_get_abs_timeout(CLOCK_MONOTONIC, &to, timeout_ns)) + return RET_FAIL; + res = futex_waitv(&waitv, 1, 0, &to, CLOCK_MONOTONIC); + test_timeout(res, &ret, "futex_waitv monotonic", ETIMEDOUT); + + /* futex_waitv with CLOCK_REALTIME */ + if (futex_get_abs_timeout(CLOCK_REALTIME, &to, timeout_ns)) + return RET_FAIL; + res = futex_waitv(&waitv, 1, 0, &to, CLOCK_REALTIME); + test_timeout(res, &ret, "futex_waitv realtime", ETIMEDOUT); + + ksft_print_cnts(); + return ret; +} |