From: Oleg Nesterov <oleg@redhat.com>
To: Peter Zijlstra <peterz@infradead.org>
Cc: Peng Tao <bergwolf@gmail.com>,
Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
Ingo Molnar <mingo@redhat.com>,
Oleg Drokin <oleg.drokin@intel.com>,
Andreas Dilger <andreas.dilger@intel.com>
Subject: Re: [PATCH RFC] sched: introduce add_wait_queue_exclusive_head
Date: Tue, 18 Mar 2014 16:47:24 +0100 [thread overview]
Message-ID: <20140318154724.GA5669@redhat.com> (raw)
In-Reply-To: <20140318140504.GD23193@laptop.programming.kicks-ass.net>
On 03/18, Peter Zijlstra wrote:
>
> I think we can avoid the entire function if we add
> WQ_FLAG_LIFO and make prepare_to_wait_event() DTRT.
Agreed, this looks very natural.
prepare_to_wait_event(WQ_FLAG_LIFO) should probably skip all "flags == 0"
entries before list_add(). Given that it is supposed that the users won't
mix exclusive and !exclusive, perhaps the additional list_for_each() won't
hurt?
> Then we only need to teach ___wait() about this; and I suppose we could
> make .exclusive=-1 be the LIFO flag.
Or we can change ___wait_event()
- if (exclusive) \
- __wait.flags = WQ_FLAG_EXCLUSIVE; \
- else \
- __wait.flags = 0; \
+ __wait.flags = exclusive; \
and obviously change the callers. Perhaps this argument should be renamed
then.
But I am fine either way, just I like the idea to extend the current
interface.
Oleg.
next prev parent reply other threads:[~2014-03-18 15:48 UTC|newest]
Thread overview: 21+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-03-18 13:10 [PATCH RFC] sched: introduce add_wait_queue_exclusive_head Peng Tao
2014-03-18 13:33 ` Peter Zijlstra
2014-03-18 13:51 ` Peng Tao
2014-03-18 14:05 ` Peter Zijlstra
2014-03-18 14:44 ` Peng Tao
2014-03-18 16:23 ` Oleg Nesterov
2014-03-19 2:22 ` Peng Tao
2014-03-19 17:33 ` Oleg Nesterov
2014-03-19 19:44 ` Dilger, Andreas
2014-03-19 19:55 ` Peter Zijlstra
2014-03-20 7:06 ` Dilger, Andreas
2014-03-20 18:49 ` Oleg Nesterov
2014-03-18 15:47 ` Oleg Nesterov [this message]
2014-03-19 2:17 ` Peng Tao
[not found] ` <20140319164907.GA10113@redhat.com>
2014-03-19 16:57 ` Peter Zijlstra
2014-03-19 17:19 ` Oleg Nesterov
2014-03-20 17:51 ` [PATCH 0/2] wait: introduce WQ_FLAG_EXCLUSIVE_HEAD Oleg Nesterov
2014-03-20 17:51 ` [PATCH 1/2] wait: turn "bool exclusive" arg of __wait_event() into wflags Oleg Nesterov
2014-03-20 17:51 ` [PATCH 2/2] wait: introduce WQ_FLAG_EXCLUSIVE_HEAD Oleg Nesterov
2014-03-21 2:45 ` [PATCH 0/2] " Dilger, Andreas
2014-03-21 18:49 ` Oleg Nesterov
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=20140318154724.GA5669@redhat.com \
--to=oleg@redhat.com \
--cc=andreas.dilger@intel.com \
--cc=bergwolf@gmail.com \
--cc=linux-kernel@vger.kernel.org \
--cc=mingo@redhat.com \
--cc=oleg.drokin@intel.com \
--cc=peterz@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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.