From: Jason Gunthorpe <jgg-uk2M96/98Pc@public.gmane.org>
To: Devesh Sharma <devesh.sharma-dY08KVG/lbpWk0Htik3J/w@public.gmane.org>
Cc: linux-rdma <linux-rdma-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>,
Doug Ledford <dledford-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>,
Leon Romanovsky <leon-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
Subject: Re: [PATCH v1 rdma-core 1/2] bnxt_re/lib: fix the memory barrier call during poll-cq
Date: Fri, 10 Nov 2017 10:30:46 -0700 [thread overview]
Message-ID: <20171110173046.GD17451@ziepe.ca> (raw)
In-Reply-To: <CANjDDBggw1wKuyh6OobsxPpe1U7esnFgD9evCoTYDV2FvnjTTQ-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
On Fri, Nov 10, 2017 at 05:01:42PM +0530, Devesh Sharma wrote:
> > And the the kernel version of this should be using READ_ONCE()
>
> Okay, we will fix this in our driver. So, READ_ONCE(CQE.valid) should
> be enough right?
Yes, I think so.
> > In user space we should probably create a
> >
> > udma_from_device_read_once(x)
> >
> > That incorporates the barrier and the 'access_once' semantics..
>
> Do you want us to pull all the defined in kernel space compiler.h
> verbitum to rdma-core
No.. kernel is using a quite different approach. We would want to use
C11 atomic_read in user space for most architectures.
Jason
--
To unsubscribe from this list: send the line "unsubscribe linux-rdma" in
the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
next prev parent reply other threads:[~2017-11-10 17:30 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-11-09 11:10 [PATCH v1 rdma-core 0/2] libbnxt_re bug fixes Devesh Sharma
[not found] ` <1510225840-20034-1-git-send-email-devesh.sharma-dY08KVG/lbpWk0Htik3J/w@public.gmane.org>
2017-11-09 11:10 ` [PATCH v1 rdma-core 1/2] bnxt_re/lib: fix the memory barrier call during poll-cq Devesh Sharma
[not found] ` <1510225840-20034-2-git-send-email-devesh.sharma-dY08KVG/lbpWk0Htik3J/w@public.gmane.org>
2017-11-09 18:05 ` Jason Gunthorpe
[not found] ` <20171109180521.GM7063-uk2M96/98Pc@public.gmane.org>
2017-11-10 11:31 ` Devesh Sharma
[not found] ` <CANjDDBggw1wKuyh6OobsxPpe1U7esnFgD9evCoTYDV2FvnjTTQ-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
2017-11-10 17:30 ` Jason Gunthorpe [this message]
2017-11-09 11:10 ` [PATCH v1 rdma-core 2/2] bnxt_re/lib: increment psn in case of 0 length packets Devesh Sharma
2017-11-09 11:54 ` [PATCH v1 rdma-core 0/2] libbnxt_re bug fixes Leon Romanovsky
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=20171110173046.GD17451@ziepe.ca \
--to=jgg-uk2m96/98pc@public.gmane.org \
--cc=devesh.sharma-dY08KVG/lbpWk0Htik3J/w@public.gmane.org \
--cc=dledford-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org \
--cc=leon-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org \
--cc=linux-rdma-u79uwXL29TY76Z2rM5mHXA@public.gmane.org \
/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