From: Jason Baron <jbaron@redhat.com>
To: Hagen Paul Pfeifer <hagen@jauu.net>
Cc: richard -rw- weinberger <richard.weinberger@gmail.com>,
torvalds@linux-foundation.org,
LKML <linux-kernel@vger.kernel.org>,
Al Viro <viro@zeniv.linux.org.uk>,
Lucas De Marchi <lucas.demarchi@profusion.mobi>,
Andrew Morton <akpm@linux-foundation.org>,
linux-fsdevel@vger.kernel.org, eric.dumazet@gmail.com
Subject: Re: [PATCH Resend] epoll: add EPOLLEXCLUSIVE support
Date: Thu, 29 Mar 2012 11:53:24 -0400 [thread overview]
Message-ID: <20120329155323.GB2424@redhat.com> (raw)
In-Reply-To: <20120329150541.GB3173@hell>
On Thu, Mar 29, 2012 at 05:05:41PM +0200, Hagen Paul Pfeifer wrote:
> * Jason Baron | 2012-03-29 10:16:53 [-0400]:
>
> >Right, for level triggered events, they all wait up. However, if you use
> >edge triggered, ie add 'EPOLLET', then the event gets 'consumed' by the
> >first thread that wakes up, and the subseqent waiters wouldn't get woken
> >up. IE you'll get one wakeup.
>
> I addressed level triggered, right - it match the model. But I don't wanted to
> wake up every every thread anyway. I don't want to abandon level triggered
> functioning.
>
> Any objective against this flag?
>
I was trying to better understand the use-case, since at least for the
test case you posted, 'EPOLLET', already does what you want.
Also, the 'EPOLLEXCLUSIVE' flag in your patch addresses multiple threads
blocking on *different* epoll fds. However, if multiple threads are
blocked on a single epoll fd, they will all be woken even if 'EPOLLEXCLUSIVE'
is set. Shouldn't 'EPOLLEXCLUSIVE' affect that case too?
Thanks,
-Jason
next prev parent reply other threads:[~2012-03-29 15:53 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-03-28 13:57 [PATCH Resend] epoll: add EPOLLEXCLUSIVE support Hagen Paul Pfeifer
2012-03-28 14:09 ` richard -rw- weinberger
2012-03-28 16:21 ` Jason Baron
2012-03-28 19:58 ` Hagen Paul Pfeifer
2012-03-29 14:16 ` Jason Baron
2012-03-29 15:05 ` Hagen Paul Pfeifer
2012-03-29 15:53 ` Jason Baron [this message]
2012-03-29 16:32 ` Hagen Paul Pfeifer
2012-03-29 18:54 ` Jason Baron
2012-03-29 21:19 ` Hagen Paul Pfeifer
2012-04-05 22:30 ` Andy Lutomirski
2012-03-29 14:51 ` Hagen Paul Pfeifer
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=20120329155323.GB2424@redhat.com \
--to=jbaron@redhat.com \
--cc=akpm@linux-foundation.org \
--cc=eric.dumazet@gmail.com \
--cc=hagen@jauu.net \
--cc=linux-fsdevel@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=lucas.demarchi@profusion.mobi \
--cc=richard.weinberger@gmail.com \
--cc=torvalds@linux-foundation.org \
--cc=viro@zeniv.linux.org.uk \
/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).