Re: [PATCH 3/7] RDMA/qedr: eliminate duplicate barriers on weakly-ordered archs

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On 2018-03-14 00:12, Jason Gunthorpe wrote:
On Tue, Mar 13, 2018 at 11:20:24PM -0400, Sinan Kaya wrote:
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@xxxxxxxxxxxxxx>
 drivers/infiniband/hw/qedr/verbs.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

Sure matches my understanding of writel_relaxed

This is part of a series, should we take just this patch through the
rdma tree? If not:

Acked-by: Jason Gunthorpe <jgg@xxxxxxxxxxxx>

Feel free to take pieces.



Thanks,
Jason
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