[PATCH 07/19] staging: lustre: simplify l_wait_event when intr handler but no timeout.

NeilBrown
2018-01-08T03:30:00Z

If l_wait_event() is given a function to be called on a signal,
but no timeout or timeout handler, then the intr function is simply
called at the end if the wait was aborted by a signal.
So a simpler way to write the code (in the one place this case is
used) it to open-code the body of the function after the
wait_event, if -ERESTARTSYS was returned.

Signed-off-by: NeilBrown <neilb@suse.com>
---
drivers/staging/lustre/lustre/ldlm/ldlm_flock.c | 30 +++++------------------
1 file changed, 7 insertions(+), 23 deletions(-)

diff --git a/drivers/staging/lustre/lustre/ldlm/ldlm_flock.c b/drivers/staging/lustre/lustre/ldlm/ldlm_flock.c
index 657ab95091a0..411b540b96d9 100644
--- a/drivers/staging/lustre/lustre/ldlm/ldlm_flock.c
+++ b/drivers/staging/lustre/lustre/ldlm/ldlm_flock.c
@@ -310,24 +310,6 @@ static int ldlm_process_flock_lock(struct ldlm_lock *req)
return LDLM_ITER_CONTINUE;
}

-struct ldlm_flock_wait_data {
- struct ldlm_lock *fwd_lock;
-};
-
-static void
-ldlm_flock_interrupted_wait(void *data)
-{
- struct ldlm_lock *lock;
-
- lock = ((struct ldlm_flock_wait_data *)data)->fwd_lock;
-
- lock_res_and_lock(lock);
-
- /* client side - set flag to prevent lock from being put on LRU list */
- ldlm_set_cbpending(lock);
- unlock_res_and_lock(lock);
-}
-
/**
* Flock completion callback function.
*
@@ -342,8 +324,6 @@ int
ldlm_flock_completion_ast(struct ldlm_lock *lock, __u64 flags, void *data)
{
struct file_lock *getlk = lock->l_ast_data;
- struct ldlm_flock_wait_data fwd;
- struct l_wait_info lwi;
int rc = 0;

OBD_FAIL_TIMEOUT(OBD_FAIL_LDLM_CP_CB_WAIT2, 4);
@@ -372,13 +352,17 @@ ldlm_flock_completion_ast(struct ldlm_lock *lock, __u64 flags, void *data)

LDLM_DEBUG(lock,
"client-side enqueue returned a blocked lock, sleeping");
- fwd.fwd_lock = lock;
- lwi = LWI_TIMEOUT_INTR(0, NULL, ldlm_flock_interrupted_wait, &fwd);

/* Go to sleep until the lock is granted. */
- rc = l_wait_event(lock->l_waitq, is_granted_or_cancelled(lock), &lwi);
+ rc = l_wait_event_abortable(lock->l_waitq, is_granted_or_cancelled(lock));

if (rc) {
+ lock_res_and_lock(lock);
+
+ /* client side - set flag to prevent lock from being put on LRU list */
+ ldlm_set_cbpending(lock);
+ unlock_res_and_lock(lock);
+
LDLM_DEBUG(lock, "client-side enqueue waking up: failed (%d)",
rc);
return rc;