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This can lead to test failures on such systems. This patch modifies the tests to check for `shmget()` support at runtime by calling it and checking for an `ENOSYS` error. If `shmget()` is not supported, the tests are skipped with a clear message, improving the user experience and preventing false negatives. This approach is more robust than relying on compile-time checks and ensures that the tests run only when the required kernel features are present. Signed-off-by: Wake Liu --- .../selftests/futex/functional/futex_wait.c | 57 ++++++++------- .../selftests/futex/functional/futex_waitv.c | 73 ++++++++++++------- 2 files changed, 78 insertions(+), 52 deletions(-) diff --git a/tools/testing/selftests/futex/functional/futex_wait.c b/tools/= testing/selftests/futex/functional/futex_wait.c index 685140d9b93d..2a834f074959 100644 --- a/tools/testing/selftests/futex/functional/futex_wait.c +++ b/tools/testing/selftests/futex/functional/futex_wait.c @@ -48,7 +48,7 @@ static void *waiterfn(void *arg) int main(int argc, char *argv[]) { int res, ret =3D RET_PASS, fd, c, shm_id; - u_int32_t f_private =3D 0, *shared_data; + u_int32_t f_private =3D 0, *shared_data =3D NULL; unsigned int flags =3D FUTEX_PRIVATE_FLAG; pthread_t waiter; void *shm; @@ -96,32 +96,37 @@ int main(int argc, char *argv[]) /* Testing an anon page shared memory */ shm_id =3D shmget(IPC_PRIVATE, 4096, IPC_CREAT | 0666); if (shm_id < 0) { - perror("shmget"); - exit(1); - } - - shared_data =3D shmat(shm_id, NULL, 0); - - *shared_data =3D 0; - futex =3D shared_data; - - info("Calling shared (page anon) futex_wait on futex: %p\n", futex); - if (pthread_create(&waiter, NULL, waiterfn, NULL)) - error("pthread_create failed\n", errno); - - usleep(WAKE_WAIT_US); - - info("Calling shared (page anon) futex_wake on futex: %p\n", futex); - res =3D futex_wake(futex, 1, 0); - if (res !=3D 1) { - ksft_test_result_fail("futex_wake shared (page anon) returned: %d %s\n", - errno, strerror(errno)); - ret =3D RET_FAIL; + if (errno =3D=3D ENOSYS) { + ksft_test_result_skip("Kernel does not support System V shared memory\n= "); + } else { + ksft_test_result_fail("shmget() failed with error: %s\n", strerror(errn= o)); + ret =3D RET_FAIL; + } } else { - ksft_test_result_pass("futex_wake shared (page anon) succeeds\n"); + shared_data =3D shmat(shm_id, NULL, 0); + + *shared_data =3D 0; + futex =3D shared_data; + + info("Calling shared (page anon) futex_wait on futex: %p\n", futex); + if (pthread_create(&waiter, NULL, waiterfn, NULL)) + error("pthread_create failed\n", errno); + + usleep(WAKE_WAIT_US); + + info("Calling shared (page anon) futex_wake on futex: %p\n", futex); + res =3D futex_wake(futex, 1, 0); + if (res !=3D 1) { + if (res < 0) + ksft_test_result_fail("futex_wake shared (page anon) faile= d with res=3D%d: %m\n", res); + else + ksft_test_result_fail("futex_wake shared (page anon) retur= ned %d, expected 1\n", res); + ret =3D RET_FAIL; + } else { + ksft_test_result_pass("futex_wake shared (page anon) succeeds\= n"); + } } =20 - /* Testing a file backed shared memory */ fd =3D open(SHM_PATH, O_RDWR | O_CREAT, S_IRUSR | S_IWUSR); if (fd < 0) { @@ -161,7 +166,8 @@ int main(int argc, char *argv[]) } =20 /* Freeing resources */ - shmdt(shared_data); + if (shared_data) + shmdt(shared_data); munmap(shm, sizeof(f_private)); remove(SHM_PATH); close(fd); @@ -169,3 +175,4 @@ int main(int argc, char *argv[]) ksft_print_cnts(); return ret; } + diff --git a/tools/testing/selftests/futex/functional/futex_waitv.c b/tools= /testing/selftests/futex/functional/futex_waitv.c index a94337f677e1..034dbfef40cb 100644 --- a/tools/testing/selftests/futex/functional/futex_waitv.c +++ b/tools/testing/selftests/futex/functional/futex_waitv.c @@ -110,40 +110,58 @@ int main(int argc, char *argv[]) } =20 /* Shared waitv */ - for (i =3D 0; i < NR_FUTEXES; i++) { - int shm_id =3D shmget(IPC_PRIVATE, 4096, IPC_CREAT | 0666); - - if (shm_id < 0) { - perror("shmget"); - exit(1); + bool shm_supported =3D true; + int shm_id =3D shmget(IPC_PRIVATE, 4096, IPC_CREAT | 0666); + + if (shm_id < 0) { + if (errno =3D=3D ENOSYS) { + shm_supported =3D false; + ksft_test_result_skip("Kernel does not support System V shared memory\n= "); + } else { + ksft_test_result_fail("shmget() failed with error: %s\n", strerror(errn= o)); + ret =3D RET_FAIL; + shm_supported =3D false; } + } else { + shmctl(shm_id, IPC_RMID, NULL); + } =20 - unsigned int *shared_data =3D shmat(shm_id, NULL, 0); + if (shm_supported) { + for (i =3D 0; i < NR_FUTEXES; i++) { + int shm_id =3D shmget(IPC_PRIVATE, 4096, IPC_CREAT | 0666); =20 - *shared_data =3D 0; - waitv[i].uaddr =3D (uintptr_t)shared_data; - waitv[i].flags =3D FUTEX_32; - waitv[i].val =3D 0; - waitv[i].__reserved =3D 0; - } + if (shm_id < 0) { + perror("shmget"); + exit(1); + } =20 - if (pthread_create(&waiter, NULL, waiterfn, NULL)) - error("pthread_create failed\n", errno); + unsigned int *shared_data =3D shmat(shm_id, NULL, 0); =20 - usleep(WAKE_WAIT_US); + *shared_data =3D 0; + waitv[i].uaddr =3D (uintptr_t)shared_data; + waitv[i].flags =3D FUTEX_32; + waitv[i].val =3D 0; + waitv[i].__reserved =3D 0; + } =20 - res =3D futex_wake(u64_to_ptr(waitv[NR_FUTEXES - 1].uaddr), 1, 0); - if (res !=3D 1) { - ksft_test_result_fail("futex_wake shared returned: %d %s\n", - res ? errno : res, - res ? strerror(errno) : ""); - ret =3D RET_FAIL; - } else { - ksft_test_result_pass("futex_waitv shared\n"); - } + if (pthread_create(&waiter, NULL, waiterfn, NULL)) + error("pthread_create failed\n", errno); =20 - for (i =3D 0; i < NR_FUTEXES; i++) - shmdt(u64_to_ptr(waitv[i].uaddr)); + usleep(WAKE_WAIT_US); + + res =3D futex_wake(u64_to_ptr(waitv[NR_FUTEXES - 1].uaddr), 1, 0); + if (res !=3D 1) { + ksft_test_result_fail("futex_wake shared returned: %d %s\n", + res ? errno : res, + res ? strerror(errno) : ""); + ret =3D RET_FAIL; + } else { + ksft_test_result_pass("futex_waitv shared\n"); + } + + for (i =3D 0; i < NR_FUTEXES; i++) + shmdt(u64_to_ptr(waitv[i].uaddr)); + } =20 /* Testing a waiter without FUTEX_32 flag */ waitv[0].flags =3D FUTEX_PRIVATE_FLAG; @@ -235,3 +253,4 @@ int main(int argc, char *argv[]) ksft_print_cnts(); return ret; } + --=20 2.50.1.703.g449372360f-goog