[PATCH 2/9] lpfc: Maintain atomic consistency of queue_claimed flag

James Smart
2020-05-01T21:43:28Z

A previous change introduced the atomic use of queue_claimed flag for
eq's and cq's. The code works fine, but the clearing of the
queue_claimed flag is not atomic.

Change queue_claimed = 0 into xchg(&queue_claimed, 0) to be consistent
for change under atomicity.

Signed-off-by: Dick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: James Smart <jsmart2021@gmail.com>
---
drivers/scsi/lpfc/lpfc_sli.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/scsi/lpfc/lpfc_sli.c b/drivers/scsi/lpfc/lpfc_sli.c
index b6fb665e6ec4..9ce37560f4c0 100644
--- a/drivers/scsi/lpfc/lpfc_sli.c
+++ b/drivers/scsi/lpfc/lpfc_sli.c
@@ -538,7 +538,7 @@ lpfc_sli4_process_eq(struct lpfc_hba *phba, struct lpfc_queue *eq,
if (count > eq->EQ_max_eqe)
eq->EQ_max_eqe = count;

- eq->queue_claimed = 0;
+ xchg(&eq->queue_claimed, 0);

rearm_and_exit:
/* Always clear the EQ. */
@@ -13694,7 +13694,7 @@ __lpfc_sli4_process_cq(struct lpfc_hba *phba, struct lpfc_queue *cq,
"0369 No entry from completion queue "
"qid=%d\n", cq->queue_id);

- cq->queue_claimed = 0;
+ xchg(&cq->queue_claimed, 0);

rearm_and_exit:
phba->sli4_hba.sli4_write_cq_db(phba, cq, consumed,
--
2.26.1