Commit 97d82a48 authored by Sinan Kaya's avatar Sinan Kaya Committed by Jason Gunthorpe

IB/mlx4: Eliminate duplicate barriers on weakly-ordered archs

Code includes wmb() followed by writel(). 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: default avatarSinan Kaya <okaya@codeaurora.org>
Reviewed-by: default avatarJason Gunthorpe <jgg@mellanox.com>
Signed-off-by: default avatarJason Gunthorpe <jgg@mellanox.com>
parent 185899ee
......@@ -3894,8 +3894,8 @@ int mlx4_ib_post_send(struct ib_qp *ibqp, struct ib_send_wr *wr,
*/
wmb();
writel(qp->doorbell_qpn,
to_mdev(ibqp->device)->uar_map + MLX4_SEND_DOORBELL);
writel_relaxed(qp->doorbell_qpn,
to_mdev(ibqp->device)->uar_map + MLX4_SEND_DOORBELL);
/*
* Make sure doorbells don't leak out of SQ spinlock
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment