From: Will Deacon <will@kernel.org>
To: Parav Pandit <parav@nvidia.com>
Cc: bagasdotme@gmail.com, arnd@arndb.de, stern@rowland.harvard.edu,
parri.andrea@gmail.com, peterz@infradead.org,
boqun.feng@gmail.com, npiggin@gmail.com, dhowells@redhat.com,
j.alglave@ucl.ac.uk, luc.maranget@inria.fr, paulmck@kernel.org,
akiyks@gmail.com, dlustig@nvidia.com, joel@joelfernandes.org,
corbet@lwn.net, linux-kernel@vger.kernel.org,
linux-arch@vger.kernel.org, linux-doc@vger.kernel.org
Subject: Re: [PATCH v5] locking/memory-barriers.txt: Improve documentation for writel() example
Date: Wed, 2 Nov 2022 06:05:54 +0000 [thread overview]
Message-ID: <20221102060553.GA15438@willie-the-truck> (raw)
In-Reply-To: <20221027201000.219731-1-parav@nvidia.com>
On Thu, Oct 27, 2022 at 11:10:00PM +0300, Parav Pandit wrote:
> The cited commit describes that when using writel(), explicit wmb()
> is not needed. wmb() is an expensive barrier. writel() uses the needed
> platform specific barrier instead of wmb().
>
> writeX() section of "KERNEL I/O BARRIER EFFECTS" already describes
> ordering of I/O accessors with MMIO writes.
>
> Hence add the comment for pseudo code of writel() and remove confusing
> text around writel() and wmb().
>
> commit 5846581e3563 ("locking/memory-barriers.txt: Fix broken DMA vs. MMIO ordering example")
>
> Signed-off-by: Parav Pandit <parav@nvidia.com>
> ---
> changelog:
> v4->v5:
> - Used suggested documentation update from Will
> - Added comment to the writel() pseudo code example
> - updated commit log for newer changes
Sorry for the delay on this, I'm really behind on patches at the moment.
This patch looks good to me, so thanks for doing it. You can either add
my:
Acked-by: Will Deacon <will@kernel.org>
or, since we worked on this together:
Co-developed-by: Will Deacon <will@kernel.org>
Signed-off-by: Will Deacon <will@kernel.org>
Cheers,
Will
next prev parent reply other threads:[~2022-11-02 6:06 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-10-27 20:10 [PATCH v5] locking/memory-barriers.txt: Improve documentation for writel() example Parav Pandit
2022-10-28 17:56 ` Paul E. McKenney
2022-10-28 17:59 ` Parav Pandit
2022-11-02 6:05 ` Will Deacon [this message]
2022-11-02 20:30 ` Paul E. McKenney
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=20221102060553.GA15438@willie-the-truck \
--to=will@kernel.org \
--cc=akiyks@gmail.com \
--cc=arnd@arndb.de \
--cc=bagasdotme@gmail.com \
--cc=boqun.feng@gmail.com \
--cc=corbet@lwn.net \
--cc=dhowells@redhat.com \
--cc=dlustig@nvidia.com \
--cc=j.alglave@ucl.ac.uk \
--cc=joel@joelfernandes.org \
--cc=linux-arch@vger.kernel.org \
--cc=linux-doc@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=luc.maranget@inria.fr \
--cc=npiggin@gmail.com \
--cc=parav@nvidia.com \
--cc=parri.andrea@gmail.com \
--cc=paulmck@kernel.org \
--cc=peterz@infradead.org \
--cc=stern@rowland.harvard.edu \
/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