From: Haakon Bugge <haakon.bugge@oracle.com>
To: Matthew Wilcox <willy@infradead.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>,
Joel Fernandes <joelagnelf@nvidia.com>,
Jonathan Corbet <corbet@lwn.net>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
"linux-arch@vger.kernel.org" <linux-arch@vger.kernel.org>,
"lkmm@lists.linux.dev" <lkmm@lists.linux.dev>,
"linux-doc@vger.kernel.org" <linux-doc@vger.kernel.org>
Subject: Re: [PATCH 1/1] docs/memory-barriers.txt: Add wait_event_cmd() and wait_event_exclusive_cmd()
Date: Thu, 26 Jun 2025 16:18:59 +0000 [thread overview]
Message-ID: <DB1B2B27-F7D4-4C5F-B9E2-4B06F5258A83@oracle.com> (raw)
In-Reply-To: <aF1kdYvCQQdIttoC@casper.infradead.org>
> On 26 Jun 2025, at 17:17, Matthew Wilcox <willy@infradead.org> wrote:
>
> On Thu, Jun 26, 2025 at 04:37:05PM +0200, Håkon Bugge wrote:
>> Add said functions to the documentation and relate them to userspace's
>> pthread_cond_wait(). The latter because when searching for
>> functionality comparable to pthread_cond_wait(), it is very hard to
>> find wait_event_cmd().
>
> Would it not go better in the kernel-doc for wait_event_cmd() in
> include/linux/wait.h?
What about both? The list with wait_foo_bars() in Documentation/memory-barriers.txt misses wait_event_cmd() and wait_event_exclusive_cmd().
But my prosaic explanation could very well go into include/linux/wait.h
>> +Note that the wait_event_cmd() and wait_event_exclusive_cmd() are the
>> +kernel's polymorphic implementation of userspace's
>> +pthread_cond_wait().
>
> Pet peeve: "Note that" adds nothing to this sentence. You can just
> write:
>
> The wait_event_cmd() and wait_event_exclusive_cmd() functions are the
> kernel's polymorphic implementation of userspace's pthread_cond_wait().
Me blushing! +1
Thxs, Håkon
>
>> +Using wait_event_cmd() or wait_event_exclusive_cmd(), cmd1 is
>> +typically a lock-release call and cmd2 a lock-acquire call. The
>> +locking primitive can be chosen, contrary to pthread_cond_wait(),
>> +where the locking type is cast in stone and is a pthread_mutex_t.
>> +
>>
>> MISCELLANEOUS FUNCTIONS
>> -----------------------
>> --
>> 2.43.5
>>
>>
prev parent reply other threads:[~2025-06-26 16:19 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-06-26 14:37 [PATCH 1/1] docs/memory-barriers.txt: Add wait_event_cmd() and wait_event_exclusive_cmd() Håkon Bugge
2025-06-26 15:17 ` Matthew Wilcox
2025-06-26 16:18 ` Haakon Bugge [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=DB1B2B27-F7D4-4C5F-B9E2-4B06F5258A83@oracle.com \
--to=haakon.bugge@oracle.com \
--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=joelagnelf@nvidia.com \
--cc=linux-arch@vger.kernel.org \
--cc=linux-doc@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=lkmm@lists.linux.dev \
--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 \
--cc=willy@infradead.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 read-only IMAP folder(s) and NNTP newsgroup(s).