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Diffstat (limited to 'src/test/test-barrier.c')
| -rw-r--r-- | src/test/test-barrier.c | 460 |
1 files changed, 460 insertions, 0 deletions
diff --git a/src/test/test-barrier.c b/src/test/test-barrier.c new file mode 100644 index 0000000000..640e508679 --- /dev/null +++ b/src/test/test-barrier.c @@ -0,0 +1,460 @@ +/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/ + +/*** + This file is part of systemd. + + Copyright 2014 David Herrmann <dh.herrmann@gmail.com> + + systemd is free software; you can redistribute it and/or modify it + under the terms of the GNU Lesser General Public License as published by + the Free Software Foundation; either version 2.1 of the License, or + (at your option) any later version. + + systemd is distributed in the hope that it will be useful, but + WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public License + along with systemd; If not, see <http://www.gnu.org/licenses/>. +***/ + +/* + * IPC barrier tests + * These tests verify the correct behavior of the IPC Barrier implementation. + * Note that the tests use alarm-timers to verify dead-locks and timeouts. These + * might not work on slow machines where 20ms are too short to perform specific + * operations (though, very unlikely). In case that turns out true, we have to + * increase it at the slightly cost of lengthen test-duration on other machines. + */ + +#include <errno.h> +#include <stdio.h> +#include <string.h> +#include <sys/time.h> +#include <sys/wait.h> +#include <unistd.h> + +#include "barrier.h" +#include "def.h" +#include "util.h" + +/* 20ms to test deadlocks; All timings use multiples of this constant as + * alarm/sleep timers. If this timeout is too small for slow machines to perform + * the requested operations, we have to increase it. On an i7 this works fine + * with 1ms base-time, so 20ms should be just fine for everyone. */ +#define BASE_TIME 20 + +static void malarm(unsigned long msecs) { + struct itimerval v = { }; + + timeval_store(&v.it_value, msecs * USEC_PER_MSEC); + assert_se(setitimer(ITIMER_REAL, &v, NULL) >= 0); +} + +static void msleep(unsigned long msecs) { + assert_se(msecs < MSEC_PER_SEC); + usleep(msecs * USEC_PER_MSEC); +} + +#define TEST_BARRIER(_FUNCTION, _CHILD_CODE, _WAIT_CHILD, _PARENT_CODE, _WAIT_PARENT) \ + static void _FUNCTION(void) { \ + Barrier b; \ + pid_t pid1, pid2; \ + \ + assert_se(barrier_init(&b) >= 0); \ + \ + pid1 = fork(); \ + assert_se(pid1 >= 0); \ + if (pid1 == 0) { \ + barrier_set_role(&b, BARRIER_CHILD); \ + { _CHILD_CODE; } \ + exit(42); \ + } \ + \ + pid2 = fork(); \ + assert_se(pid2 >= 0); \ + if (pid2 == 0) { \ + barrier_set_role(&b, BARRIER_PARENT); \ + { _PARENT_CODE; } \ + exit(42); \ + } \ + \ + barrier_destroy(&b); \ + malarm(999); \ + { _WAIT_CHILD; } \ + { _WAIT_PARENT; } \ + malarm(0); \ + } + +#define TEST_BARRIER_WAIT_SUCCESS(_pid) \ + ({ \ + int pidr, status; \ + pidr = waitpid(_pid, &status, 0); \ + assert_se(pidr == _pid); \ + assert_se(WIFEXITED(status)); \ + assert_se(WEXITSTATUS(status) == 42); \ + }) + +#define TEST_BARRIER_WAIT_ALARM(_pid) \ + ({ \ + int pidr, status; \ + pidr = waitpid(_pid, &status, 0); \ + assert_se(pidr == _pid); \ + assert_se(WIFSIGNALED(status)); \ + assert_se(WTERMSIG(status) == SIGALRM); \ + }) + +/* + * Test basic sync points + * This places a barrier in both processes and waits synchronously for them. + * The timeout makes sure the sync works as expected. The msleep() on one side + * makes sure the exit of the parent does not overwrite previous barriers. Due + * to the msleep(), we know that the parent already exited, thus there's a + * pending HUP on the pipe. However, the barrier_sync() prefers reads on the + * eventfd, thus we can safely wait on the barrier. + */ +TEST_BARRIER(test_barrier_sync, + ({ + malarm(BASE_TIME * 10); + assert_se(barrier_place(&b)); + msleep(BASE_TIME * 2); + assert_se(barrier_sync(&b)); + }), + TEST_BARRIER_WAIT_SUCCESS(pid1), + ({ + malarm(BASE_TIME * 10); + assert_se(barrier_place(&b)); + assert_se(barrier_sync(&b)); + }), + TEST_BARRIER_WAIT_SUCCESS(pid2)); + +/* + * Test wait_next() + * This places a barrier in the parent and syncs on it. The child sleeps while + * the parent places the barrier and then waits for a barrier. The wait will + * succeed as the child hasn't read the parent's barrier, yet. The following + * barrier and sync synchronize the exit. + */ +TEST_BARRIER(test_barrier_wait_next, + ({ + msleep(100); + malarm(BASE_TIME * 10); + assert_se(barrier_wait_next(&b)); + assert_se(barrier_place(&b)); + assert_se(barrier_sync(&b)); + }), + TEST_BARRIER_WAIT_SUCCESS(pid1), + ({ + malarm(400); + assert_se(barrier_place(&b)); + assert_se(barrier_sync(&b)); + }), + TEST_BARRIER_WAIT_SUCCESS(pid2)); + +/* + * Test wait_next() multiple times + * This places two barriers in the parent and waits for the child to exit. The + * child sleeps 20ms so both barriers _should_ be in place. It then waits for + * the parent to place the next barrier twice. The first call will fetch both + * barriers and return. However, the second call will stall as the parent does + * not place a 3rd barrier (the sleep caught two barriers). wait_next() is does + * not look at barrier-links so this stall is expected. Thus this test times + * out. + */ +TEST_BARRIER(test_barrier_wait_next_twice, + ({ + msleep(BASE_TIME); + malarm(BASE_TIME); + assert_se(barrier_wait_next(&b)); + assert_se(barrier_wait_next(&b)); + assert_se(0); + }), + TEST_BARRIER_WAIT_ALARM(pid1), + ({ + malarm(BASE_TIME * 10); + assert_se(barrier_place(&b)); + assert_se(barrier_place(&b)); + msleep(BASE_TIME * 2); + }), + TEST_BARRIER_WAIT_SUCCESS(pid2)); + +/* + * Test wait_next() with local barriers + * This is the same as test_barrier_wait_next_twice, but places local barriers + * between both waits. This does not have any effect on the wait so it times out + * like the other test. + */ +TEST_BARRIER(test_barrier_wait_next_twice_local, + ({ + msleep(BASE_TIME); + malarm(BASE_TIME); + assert_se(barrier_wait_next(&b)); + assert_se(barrier_place(&b)); + assert_se(barrier_place(&b)); + assert_se(barrier_wait_next(&b)); + assert_se(0); + }), + TEST_BARRIER_WAIT_ALARM(pid1), + ({ + malarm(BASE_TIME * 10); + assert_se(barrier_place(&b)); + assert_se(barrier_place(&b)); + msleep(BASE_TIME * 2); + }), + TEST_BARRIER_WAIT_SUCCESS(pid2)); + +/* + * Test wait_next() with sync_next() + * This is again the same as test_barrier_wait_next_twice but uses a + * synced wait as the second wait. This works just fine because the local state + * has no barriers placed, therefore, the remote is always in sync. + */ +TEST_BARRIER(test_barrier_wait_next_twice_sync, + ({ + msleep(BASE_TIME); + malarm(BASE_TIME); + assert_se(barrier_wait_next(&b)); + assert_se(barrier_sync_next(&b)); + }), + TEST_BARRIER_WAIT_SUCCESS(pid1), + ({ + malarm(BASE_TIME * 10); + assert_se(barrier_place(&b)); + assert_se(barrier_place(&b)); + }), + TEST_BARRIER_WAIT_SUCCESS(pid2)); + +/* + * Test wait_next() with sync_next() and local barriers + * This is again the same as test_barrier_wait_next_twice_local but uses a + * synced wait as the second wait. This works just fine because the local state + * is in sync with the remote. + */ +TEST_BARRIER(test_barrier_wait_next_twice_local_sync, + ({ + msleep(BASE_TIME); + malarm(BASE_TIME); + assert_se(barrier_wait_next(&b)); + assert_se(barrier_place(&b)); + assert_se(barrier_place(&b)); + assert_se(barrier_sync_next(&b)); + }), + TEST_BARRIER_WAIT_SUCCESS(pid1), + ({ + malarm(BASE_TIME * 10); + assert_se(barrier_place(&b)); + assert_se(barrier_place(&b)); + }), + TEST_BARRIER_WAIT_SUCCESS(pid2)); + +/* + * Test sync_next() and sync() + * This tests sync_*() synchronizations and makes sure they work fine if the + * local state is behind the remote state. + */ +TEST_BARRIER(test_barrier_sync_next, + ({ + malarm(BASE_TIME * 10); + assert_se(barrier_sync_next(&b)); + assert_se(barrier_sync(&b)); + assert_se(barrier_place(&b)); + assert_se(barrier_place(&b)); + assert_se(barrier_sync_next(&b)); + assert_se(barrier_sync_next(&b)); + assert_se(barrier_sync(&b)); + }), + TEST_BARRIER_WAIT_SUCCESS(pid1), + ({ + malarm(BASE_TIME * 10); + msleep(BASE_TIME); + assert_se(barrier_place(&b)); + assert_se(barrier_place(&b)); + assert_se(barrier_sync(&b)); + }), + TEST_BARRIER_WAIT_SUCCESS(pid2)); + +/* + * Test sync_next() and sync() with local barriers + * This tests timeouts if sync_*() is used if local barriers are placed but the + * remote didn't place any. + */ +TEST_BARRIER(test_barrier_sync_next_local, + ({ + malarm(BASE_TIME); + assert_se(barrier_place(&b)); + assert_se(barrier_sync_next(&b)); + assert_se(0); + }), + TEST_BARRIER_WAIT_ALARM(pid1), + ({ + msleep(BASE_TIME * 2); + }), + TEST_BARRIER_WAIT_SUCCESS(pid2)); + +/* + * Test sync_next() and sync() with local barriers and abortion + * This is the same as test_barrier_sync_next_local but aborts the sync in the + * parent. Therefore, the sync_next() succeeds just fine due to the abortion. + */ +TEST_BARRIER(test_barrier_sync_next_local_abort, + ({ + malarm(BASE_TIME * 10); + assert_se(barrier_place(&b)); + assert_se(!barrier_sync_next(&b)); + }), + TEST_BARRIER_WAIT_SUCCESS(pid1), + ({ + assert_se(barrier_abort(&b)); + }), + TEST_BARRIER_WAIT_SUCCESS(pid2)); + +/* + * Test matched wait_abortion() + * This runs wait_abortion() with remote abortion. + */ +TEST_BARRIER(test_barrier_wait_abortion, + ({ + malarm(BASE_TIME * 10); + assert_se(barrier_wait_abortion(&b)); + }), + TEST_BARRIER_WAIT_SUCCESS(pid1), + ({ + assert_se(barrier_abort(&b)); + }), + TEST_BARRIER_WAIT_SUCCESS(pid2)); + +/* + * Test unmatched wait_abortion() + * This runs wait_abortion() without any remote abortion going on. It thus must + * timeout. + */ +TEST_BARRIER(test_barrier_wait_abortion_unmatched, + ({ + malarm(BASE_TIME); + assert_se(barrier_wait_abortion(&b)); + assert_se(0); + }), + TEST_BARRIER_WAIT_ALARM(pid1), + ({ + msleep(BASE_TIME * 2); + }), + TEST_BARRIER_WAIT_SUCCESS(pid2)); + +/* + * Test matched wait_abortion() with local abortion + * This runs wait_abortion() with local and remote abortion. + */ +TEST_BARRIER(test_barrier_wait_abortion_local, + ({ + malarm(BASE_TIME * 10); + assert_se(barrier_abort(&b)); + assert_se(!barrier_wait_abortion(&b)); + }), + TEST_BARRIER_WAIT_SUCCESS(pid1), + ({ + assert_se(barrier_abort(&b)); + }), + TEST_BARRIER_WAIT_SUCCESS(pid2)); + +/* + * Test unmatched wait_abortion() with local abortion + * This runs wait_abortion() with only local abortion. This must time out. + */ +TEST_BARRIER(test_barrier_wait_abortion_local_unmatched, + ({ + malarm(BASE_TIME); + assert_se(barrier_abort(&b)); + assert_se(!barrier_wait_abortion(&b)); + assert_se(0); + }), + TEST_BARRIER_WAIT_ALARM(pid1), + ({ + msleep(BASE_TIME * 2); + }), + TEST_BARRIER_WAIT_SUCCESS(pid2)); + +/* + * Test child exit + * Place barrier and sync with the child. The child only exits()s, which should + * cause an implicit abortion and wake the parent. + */ +TEST_BARRIER(test_barrier_exit, + ({ + }), + TEST_BARRIER_WAIT_SUCCESS(pid1), + ({ + malarm(BASE_TIME * 10); + assert_se(barrier_place(&b)); + assert_se(!barrier_sync(&b)); + }), + TEST_BARRIER_WAIT_SUCCESS(pid2)); + +/* + * Test child exit with sleep + * Same as test_barrier_exit but verifies the test really works due to the + * child-exit. We add a usleep() which triggers the alarm in the parent and + * causes the test to time out. + */ +TEST_BARRIER(test_barrier_no_exit, + ({ + msleep(BASE_TIME * 2); + }), + TEST_BARRIER_WAIT_SUCCESS(pid1), + ({ + malarm(BASE_TIME); + assert_se(barrier_place(&b)); + assert_se(!barrier_sync(&b)); + }), + TEST_BARRIER_WAIT_ALARM(pid2)); + +/* + * Test pending exit against sync + * The parent places a barrier *and* exits. The 20ms wait in the child + * guarantees both are pending. However, our logic prefers pending barriers over + * pending exit-abortions (unlike normal abortions), thus the wait_next() must + * succeed, same for the sync_next() as our local barrier-count is smaller than + * the remote. Once we place a barrier our count is equal, so the sync still + * succeeds. Only if we place one more barrier, we're ahead of the remote, thus + * we will fail due to HUP on the pipe. + */ +TEST_BARRIER(test_barrier_pending_exit, + ({ + malarm(BASE_TIME * 4); + msleep(BASE_TIME * 2); + assert_se(barrier_wait_next(&b)); + assert_se(barrier_sync_next(&b)); + assert_se(barrier_place(&b)); + assert_se(barrier_sync_next(&b)); + assert_se(barrier_place(&b)); + assert_se(!barrier_sync_next(&b)); + }), + TEST_BARRIER_WAIT_SUCCESS(pid1), + ({ + assert_se(barrier_place(&b)); + }), + TEST_BARRIER_WAIT_SUCCESS(pid2)); + +int main(int argc, char *argv[]) { + log_parse_environment(); + log_open(); + + test_barrier_sync(); + test_barrier_wait_next(); + test_barrier_wait_next_twice(); + test_barrier_wait_next_twice_sync(); + test_barrier_wait_next_twice_local(); + test_barrier_wait_next_twice_local_sync(); + test_barrier_sync_next(); + test_barrier_sync_next_local(); + test_barrier_sync_next_local_abort(); + test_barrier_wait_abortion(); + test_barrier_wait_abortion_unmatched(); + test_barrier_wait_abortion_local(); + test_barrier_wait_abortion_local_unmatched(); + test_barrier_exit(); + test_barrier_no_exit(); + test_barrier_pending_exit(); + + return 0; +} |