The locker was waiting for sem_otime on sem0 to became non-zero after
incrementing sem0 himself. So sem_otime was never 0 at the time of
checking it, so the check was redundant/wrong.
This patch:
- moves the increment of sem1 to the lock-tester site
- lock-setter waits for that sem1 event, for which this patch replaces
the wait loop on sem_otime with GETVAL loop, adding a small sleep
- increment of sem0 to 2 moved past that sem1 event. That sem0 event
is currently not used/waited.
This guarantees that the lock-setter is working only after lock-getter
is fully initialized.
CC: fstests@xxxxxxxxxxxxxxx
CC: Murphy Zhou <xzhou@xxxxxxxxxx>
CC: Jeff Layton <jlayton@xxxxxxxxxx>
CC: Zorro Lang <zlang@xxxxxxxxxx>
Signed-off-by: Stas Sergeev <stsp2@xxxxxxxxx>
---
src/t_ofd_locks.c | 44 +++++++++++++++++++++++++-------------------
1 file changed, 25 insertions(+), 19 deletions(-)
diff --git a/src/t_ofd_locks.c b/src/t_ofd_locks.c
index 95739dc7..b7b2022d 100644
--- a/src/t_ofd_locks.c
+++ b/src/t_ofd_locks.c
@@ -296,32 +296,29 @@ int main(int argc, char **argv)
semu.array = vals;
if (semctl(semid, 2, SETALL, semu) == -1)
err_exit("init sem", errno);
- /* Inc both new sem to 2 */
- sop.sem_num = 0;
- sop.sem_op = 1;
- sop.sem_flg = 0;
- ts.tv_sec = 5;
- ts.tv_nsec = 0;
- if (semtimedop(semid, &sop, 1, &ts) == -1)
- err_exit("inc sem0 2", errno);
- sop.sem_num = 1;
- sop.sem_op = 1;
- sop.sem_flg = 0;
- ts.tv_sec = 5;
- ts.tv_nsec = 0;
- if (semtimedop(semid, &sop, 1, &ts) == -1)
- err_exit("inc sem1 2", errno);
/*
- * Wait initialization complete. semctl(2) only update
- * sem_ctime, semop(2) will update sem_otime.
+ * Wait initialization complete.
*/
ret = -1;
do {
+ if (ret != -1)
+ usleep(100000);
memset(&sem_ds, 0, sizeof(sem_ds));
semu.buf = &sem_ds;
- ret = semctl(semid, 0, IPC_STAT, semu);
- } while (!(ret == 0 && sem_ds.sem_otime != 0));
+ ret = semctl(semid, 1, GETVAL, semu);
+ if (ret == -1)
+ err_exit("wait sem1 2", errno);
+ } while (ret != 2);
+
+ /* Inc sem0 to 2 */
+ sop.sem_num = 0;
+ sop.sem_op = 1;
+ sop.sem_flg = 0;
+ ts.tv_sec = 5;
+ ts.tv_nsec = 0;
+ if (semtimedop(semid, &sop, 1, &ts) == -1)
+ err_exit("inc sem0 2", errno);
/* place the lock */
if (fcntl(fd, setlk_macro, &flk) < 0)
@@ -388,6 +385,15 @@ int main(int argc, char **argv)
}
} while (1);
+ /* inc sem1 to 2 (initialization completed) */
+ sop.sem_num = 1;
+ sop.sem_op = 1;
+ sop.sem_flg = 0;
+ ts.tv_sec = 5;
+ ts.tv_nsec = 0;
+ if (semtimedop(semid, &sop, 1, &ts) == -1)
+ err_exit("inc sem1 2", errno);
+
/* wait sem0 == 0 (setlk and close fd done) */
sop.sem_num = 0;
sop.sem_op = 0;
--
2.39.2
