From: Leon Romanovsky <leon@kernel.org>
To: Tatyana Nikolova <tatyana.e.nikolova@intel.com>
Cc: jgg@nvidia.com, dledford@redhat.com, linux-rdma@vger.kernel.org
Subject: Re: [PATCH rdma-core] irdma: Remove optimization algorithm for QP doorbell
Date: Wed, 22 Sep 2021 11:40:09 +0300 [thread overview]
Message-ID: <YUrr6Vjm/YID9CQv@unreal> (raw)
In-Reply-To: <20210920213723.1279-1-tatyana.e.nikolova@intel.com>
On Mon, Sep 20, 2021 at 04:37:23PM -0500, Tatyana Nikolova wrote:
> Remove optimization algorithm for QP doorbell, because
> without an mfence the algorithm incorrectly skips ringing
> the doorbell. This causes applicaitons like OpenMPI with
> high number of connections to stall waiting for completion.
>
> Enforcing the order of the write of the WQE valid bit
> and the read of the SQ tail is required by the algorithm,
> but furher investigation is necessary because this does not
> appear sufficient for the algorithm to work. In the meantime,
> remove the doorbell optimization and fix the MPI failures.
>
> Signed-off-by: Tatyana Nikolova <tatyana.e.nikolova@intel.com>
> ---
> providers/irdma/uk.c | 29 ++---------------------------
> 1 file changed, 2 insertions(+), 27 deletions(-)
>
Thanks, applied.
prev parent reply other threads:[~2021-09-22 8:40 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-09-20 21:37 [PATCH rdma-core] irdma: Remove optimization algorithm for QP doorbell Tatyana Nikolova
2021-09-22 8:40 ` Leon Romanovsky [this message]
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=YUrr6Vjm/YID9CQv@unreal \
--to=leon@kernel.org \
--cc=dledford@redhat.com \
--cc=jgg@nvidia.com \
--cc=linux-rdma@vger.kernel.org \
--cc=tatyana.e.nikolova@intel.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).