From: okaya@codeaurora.org (Sinan Kaya)
To: linux-arm-kernel@lists.infradead.org
Subject: [PATCH v4 6/6] RDMA/qedr: eliminate duplicate barriers on weakly-ordered archs #2
Date: Mon, 19 Mar 2018 22:47:48 -0400 [thread overview]
Message-ID: <1521514068-8856-7-git-send-email-okaya@codeaurora.org> (raw)
In-Reply-To: <1521514068-8856-1-git-send-email-okaya@codeaurora.org>
Code includes wmb() followed by writel() in multiple places. writel()
already has a barrier on some architectures like arm64.
This ends up CPU observing two barriers back to back before executing the
register write.
Since code already has an explicit barrier call, changing writel() to
writel_relaxed().
Signed-off-by: Sinan Kaya <okaya@codeaurora.org>
---
drivers/infiniband/hw/qedr/verbs.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/infiniband/hw/qedr/verbs.c b/drivers/infiniband/hw/qedr/verbs.c
index ccd55f4..db60360 100644
--- a/drivers/infiniband/hw/qedr/verbs.c
+++ b/drivers/infiniband/hw/qedr/verbs.c
@@ -860,7 +860,7 @@ static void doorbell_cq(struct qedr_cq *cq, u32 cons, u8 flags)
wmb();
cq->db.data.agg_flags = flags;
cq->db.data.value = cpu_to_le32(cons);
- writeq(cq->db.raw, cq->db_addr);
+ writeq_relaxed(cq->db.raw, cq->db_addr);
/* Make sure write would stick */
mmiowb();
@@ -3338,7 +3338,7 @@ int qedr_post_recv(struct ib_qp *ibqp, struct ib_recv_wr *wr,
qp->rq.db_data.data.value++;
- writel(qp->rq.db_data.raw, qp->rq.db);
+ writel_relaxed(qp->rq.db_data.raw, qp->rq.db);
/* Make sure write sticks */
mmiowb();
--
2.7.4
next prev parent reply other threads:[~2018-03-20 2:47 UTC|newest]
Thread overview: 47+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-03-20 2:47 [PATCH v4 0/6] ib: Eliminate duplicate barriers on weakly-ordered archs Sinan Kaya
2018-03-20 2:47 ` [PATCH v4 1/6] RDMA/bnxt_re: " Sinan Kaya
2018-03-20 14:48 ` Jason Gunthorpe
2018-03-20 15:00 ` Sinan Kaya
2018-03-20 15:08 ` Sinan Kaya
2018-03-20 15:23 ` Jason Gunthorpe
2018-03-20 15:20 ` Jason Gunthorpe
2018-03-20 15:30 ` Sinan Kaya
2018-03-20 16:02 ` Jason Gunthorpe
2018-03-20 2:47 ` [PATCH v4 2/6] IB/mlx4: " Sinan Kaya
2018-03-20 14:48 ` Jason Gunthorpe
2018-03-20 2:47 ` [PATCH v4 3/6] RDMA/i40iw: " Sinan Kaya
2018-03-20 14:56 ` Jason Gunthorpe
2018-03-21 13:38 ` Shiraz Saleem
2018-03-21 20:02 ` Jason Gunthorpe
2018-03-21 21:01 ` Sinan Kaya
2018-03-20 2:47 ` [PATCH v4 4/6] infiniband: cxgb4: " Sinan Kaya
2018-03-20 14:51 ` Jason Gunthorpe
2018-03-20 15:10 ` Steve Wise
2018-03-20 15:38 ` Steve Wise
2018-03-22 6:44 ` kbuild test robot
2018-03-22 12:24 ` okaya at codeaurora.org
2018-03-22 12:48 ` okaya at codeaurora.org
2018-03-22 14:33 ` Sinan Kaya
2018-03-22 14:40 ` Steve Wise
2018-03-22 14:52 ` Sinan Kaya
2018-03-22 16:28 ` Steve Wise
2018-03-22 19:44 ` Casey Leedom
2018-03-22 20:16 ` Jason Gunthorpe
2018-03-22 20:45 ` Casey Leedom
2018-03-22 21:25 ` Jason Gunthorpe
2018-03-22 21:27 ` Sinan Kaya
2018-03-22 22:02 ` Casey Leedom
[not found] ` <437ab002-b8db-24aa-583e-0e61d61aaa97@codeaurora.org>
2018-03-22 18:46 ` Jason Gunthorpe
2018-03-22 18:48 ` Jason Gunthorpe
2018-03-22 18:58 ` Sinan Kaya
2018-03-23 4:14 ` kbuild test robot
2018-03-20 2:47 ` [PATCH v4 5/6] IB/nes: " Sinan Kaya
2018-03-20 14:54 ` Jason Gunthorpe
2018-03-20 15:23 ` Sinan Kaya
2018-03-20 16:01 ` Jason Gunthorpe
2018-03-20 16:08 ` Sinan Kaya
2018-03-20 16:29 ` Jason Gunthorpe
2018-03-20 2:47 ` Sinan Kaya [this message]
2018-03-20 7:38 ` [PATCH v4 6/6] RDMA/qedr: eliminate duplicate barriers on weakly-ordered archs #2 Kalderon, Michal
2018-03-20 14:55 ` Jason Gunthorpe
2018-03-21 20:08 ` [PATCH v4 0/6] ib: Eliminate duplicate barriers on weakly-ordered archs Jason Gunthorpe
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