[PATCH 11/35] staging: lustre: ptlrpc: race at req processing

[James Simmons]

From: Alexander Boyko <alexander_boyko@xxxxxxxxxxx>

Fix: 5c689e689baa ("staging/lustre/ptlrpc: race at req processing")
decreased the race window, but does not remove it. Disable rq_resend
right after MSG_REPLAY flag set. Import lock protects two threads
from race between set/clear MSG_REPLAY and rq_resend flags.

Signed-off-by: Alexander Boyko <alexander_boyko@xxxxxxxxxxx>
Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-5554
Xyratex-bug-id: MRP-1888
Reviewed-on: http://review.whamcloud.com/10735
Reviewed-by: Niu Yawei <yawei.niu@xxxxxxxxx>
Reviewed-by: Mike Pershin <mike.pershin@xxxxxxxxx>
Reviewed-by: Oleg Drokin <oleg.drokin@xxxxxxxxx>
Signed-off-by: James Simmons <jsimmons@xxxxxxxxxxxxx>
---
 drivers/staging/lustre/lustre/ptlrpc/client.c |    4 ++++
 1 files changed, 4 insertions(+), 0 deletions(-)

diff --git a/drivers/staging/lustre/lustre/ptlrpc/client.c b/drivers/staging/lustre/lustre/ptlrpc/client.c
index b940e24..d2f4cd5 100644
--- a/drivers/staging/lustre/lustre/ptlrpc/client.c
+++ b/drivers/staging/lustre/lustre/ptlrpc/client.c
@@ -2690,6 +2690,10 @@ void ptlrpc_retain_replayable_request(struct ptlrpc_request *req,
 
 	lustre_msg_add_flags(req->rq_reqmsg, MSG_REPLAY);
 
+	spin_lock(&req->rq_lock);
+	req->rq_resend = 0;
+	spin_unlock(&req->rq_lock);
+
 	LASSERT(imp->imp_replayable);
 	/* Balanced in ptlrpc_free_committed, usually. */
 	ptlrpc_request_addref(req);
-- 
1.7.1