From: Randy Dunlap <rdunlap@infradead.org>
To: "Jonathan Neuschäfer" <j.neuschaefer@gmx.net>, linux-doc@vger.kernel.org
Cc: Alan Stern <stern@rowland.harvard.edu>,
Andrea Parri <parri.andrea@gmail.com>,
Will Deacon <will@kernel.org>,
Peter Zijlstra <peterz@infradead.org>,
Boqun Feng <boqun.feng@gmail.com>,
Nicholas Piggin <npiggin@gmail.com>,
David Howells <dhowells@redhat.com>,
Jade Alglave <j.alglave@ucl.ac.uk>,
Luc Maranget <luc.maranget@inria.fr>,
"Paul E. McKenney" <paulmck@kernel.org>,
Akira Yokosawa <akiyks@gmail.com>,
Daniel Lustig <dlustig@nvidia.com>,
Jonathan Corbet <corbet@lwn.net>,
linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org
Subject: Re: [PATCH 3/3] docs: atomic_ops: Steer readers towards using refcount_t for reference counts
Date: Sun, 8 Mar 2020 14:07:46 -0700 [thread overview]
Message-ID: <7ff7dc4e-d606-e2a1-edce-a0485e948e48@infradead.org> (raw)
In-Reply-To: <20200308200007.23314-1-j.neuschaefer@gmx.net>
On 3/8/20 1:00 PM, Jonathan Neuschäfer wrote:
> Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
> ---
> Documentation/core-api/atomic_ops.rst | 6 ++++++
> Documentation/core-api/refcount-vs-atomic.rst | 2 ++
> 2 files changed, 8 insertions(+)
>
> diff --git a/Documentation/core-api/atomic_ops.rst b/Documentation/core-api/atomic_ops.rst
> index 73033fc954ad..37a0ffe1a9f1 100644
> --- a/Documentation/core-api/atomic_ops.rst
> +++ b/Documentation/core-api/atomic_ops.rst
> @@ -392,6 +392,12 @@ be guaranteed that no other entity can be accessing the object::
> memory barriers in kfree_skb() that exposed the atomic_t memory barrier
> requirements quite clearly.
>
> +.. note::
> +
> + More recently, reference counts are implement using the
implemented
> + :ref:`refcount_t <refcount_t_vs_atomic_t>` type, which works like
> + atomic_t but protects against wraparound.
> +
> Given the above scheme, it must be the case that the obj->active
> update done by the obj list deletion be visible to other processors
> before the atomic counter decrement is performed.
--
~Randy
next prev parent reply other threads:[~2020-03-08 21:08 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-03-08 19:56 [PATCH 0/3] docs: a few improvements for atomic_ops.rst Jonathan Neuschäfer
2020-03-08 19:56 ` [PATCH 1/3] docs: atomic_ops: Remove colons where they don't make sense Jonathan Neuschäfer
2020-03-08 19:56 ` [PATCH 2/3] docs: atomic_ops: Move two paragraphs into the warning block above Jonathan Neuschäfer
2020-03-08 20:00 ` [PATCH 3/3] docs: atomic_ops: Steer readers towards using refcount_t for reference counts Jonathan Neuschäfer
2020-03-08 21:07 ` Randy Dunlap [this message]
2020-03-08 21:25 ` Jonathan Neuschäfer
2020-03-09 9:06 ` [PATCH 0/3] docs: a few improvements for atomic_ops.rst Peter Zijlstra
2020-03-16 15:48 ` Will Deacon
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=7ff7dc4e-d606-e2a1-edce-a0485e948e48@infradead.org \
--to=rdunlap@infradead.org \
--cc=akiyks@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=j.neuschaefer@gmx.net \
--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=parri.andrea@gmail.com \
--cc=paulmck@kernel.org \
--cc=peterz@infradead.org \
--cc=stern@rowland.harvard.edu \
--cc=will@kernel.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;
as well as URLs for NNTP newsgroup(s).