[PATCH 12/19] staging: lustre: make polling loop in ptlrpc_unregister_bulk more obvious

NeilBrown
2018-01-08T03:30:39Z

This use of l_wait_event() is a polling loop that re-checks
every second. Make this more obvious with a while loop
and wait_event_idle_timeout().

Signed-off-by: NeilBrown <neilb@suse.com>
---
drivers/staging/lustre/lustre/ptlrpc/niobuf.c | 15 ++++++++-------
1 file changed, 8 insertions(+), 7 deletions(-)

diff --git a/drivers/staging/lustre/lustre/ptlrpc/niobuf.c b/drivers/staging/lustre/lustre/ptlrpc/niobuf.c
index 0c2ded721c49..86883abaad2c 100644
--- a/drivers/staging/lustre/lustre/ptlrpc/niobuf.c
+++ b/drivers/staging/lustre/lustre/ptlrpc/niobuf.c
@@ -229,7 +229,6 @@ int ptlrpc_unregister_bulk(struct ptlrpc_request *req, int async)
{
struct ptlrpc_bulk_desc *desc = req->rq_bulk;
wait_queue_head_t *wq;
- struct l_wait_info lwi;
int rc;

LASSERT(!in_interrupt()); /* might sleep */
@@ -246,7 +245,7 @@ int ptlrpc_unregister_bulk(struct ptlrpc_request *req, int async)

/* the unlink ensures the callback happens ASAP and is the last
* one. If it fails, it must be because completion just happened,
- * but we must still l_wait_event() in this case to give liblustre
+ * but we must still wait_event() in this case to give liblustre
* a chance to run client_bulk_callback()
*/
mdunlink_iterate_helper(desc->bd_mds, desc->bd_md_max_brw);
@@ -270,15 +269,17 @@ int ptlrpc_unregister_bulk(struct ptlrpc_request *req, int async)
/* Network access will complete in finite time but the HUGE
* timeout lets us CWARN for visibility of sluggish LNDs
*/
- lwi = LWI_TIMEOUT_INTERVAL(LONG_UNLINK * HZ,
- HZ, NULL, NULL);
- rc = l_wait_event(*wq, !ptlrpc_client_bulk_active(req), &lwi);
- if (rc == 0) {
+ int cnt = 0;
+ while (cnt < LONG_UNLINK &&
+ (rc = wait_event_idle_timeout(*wq,
+ !ptlrpc_client_bulk_active(req),
+ HZ)) == 0)
+ cnt += 1;
+ if (rc > 0) {
ptlrpc_rqphase_move(req, req->rq_next_phase);
return 1;
}

- LASSERT(rc == -ETIMEDOUT);
DEBUG_REQ(D_WARNING, req, "Unexpectedly long timeout: desc %p",
desc);
}