mirror of https://lore.kernel.org/lkml/
 help / color / mirror / Atom feed
From: Andi Kleen <andi@firstfloor.org>
To: Davidlohr Bueso <davidlohr.bueso@hp.com>
Cc: akpm@linux-foundation.org, torvalds@linux-foundation.org,
	riel@redhat.com, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 04/11] ipc: move locking out of ipcctl_pre_down_nolock
Date: Thu, 16 May 2013 10:55:28 -0700	[thread overview]
Message-ID: <m2vc6i3j3j.fsf@firstfloor.org> (raw)
In-Reply-To: <1368666490-29055-5-git-send-email-davidlohr.bueso@hp.com> (Davidlohr Bueso's message of "Wed, 15 May 2013 18:08:03 -0700")

Davidlohr Bueso <davidlohr.bueso@hp.com> writes:

> This function currently acquires both the rw_mutex and the rcu lock on
> successful lookups, leaving the callers to explicitly unlock them, creating
> another two level locking situation.

Note that the rcu read lock is not a real lock, so it doesn't have the
usual ordering problems.

-Andi

-- 
ak@linux.intel.com -- Speaking for myself only

  reply	other threads:[~2013-05-16 17:55 UTC|newest]

Thread overview: 19+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-05-16  1:07 [PATCH 00/11] sysv mqueue: do not hold the ipc lock unnecessarily Davidlohr Bueso
2013-05-16  1:08 ` [PATCH 01/11] ipc: move rcu lock out of ipc_addid Davidlohr Bueso
2013-05-16  1:08 ` [PATCH 02/11] ipc: introduce ipc object locking helpers Davidlohr Bueso
2013-05-16  1:08 ` [PATCH 03/11] ipc: close open coded spin lock calls Davidlohr Bueso
2013-05-16  1:08 ` [PATCH 04/11] ipc: move locking out of ipcctl_pre_down_nolock Davidlohr Bueso
2013-05-16 17:55   ` Andi Kleen [this message]
2013-05-24 20:16   ` Andrew Morton
2013-05-24 22:21     ` Davidlohr Bueso
2013-05-24 22:29       ` Andrew Morton
2013-05-16  1:08 ` [PATCH 05/11] ipc,msg: shorten critical region in msgctl_down Davidlohr Bueso
2013-05-16  1:08 ` [PATCH 06/11] ipc,msg: introduce msgctl_nolock Davidlohr Bueso
2013-05-16  1:08 ` [PATCH 07/11] ipc,msg: introduce lockless functions to obtain the ipc object Davidlohr Bueso
2013-05-16  1:08 ` [PATCH 08/11] ipc,msg: make msgctl_nolock lockless Davidlohr Bueso
2013-05-16  1:08 ` [PATCH 09/11] ipc,msg: shorten critical region in msgsnd Davidlohr Bueso
2013-05-16  1:08 ` [PATCH 10/11] ipc,msg: shorten critical region in msgrcv Davidlohr Bueso
2013-05-16  1:08 ` [PATCH 11/11] ipc: remove unused functions Davidlohr Bueso
2013-05-16 14:12 ` [PATCH 00/11] sysv mqueue: do not hold the ipc lock unnecessarily Linus Torvalds
2013-05-16 16:41   ` Davidlohr Bueso
2013-05-24  1:45 ` Davidlohr Bueso

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=m2vc6i3j3j.fsf@firstfloor.org \
    --to=andi@firstfloor.org \
    --cc=akpm@linux-foundation.org \
    --cc=davidlohr.bueso@hp.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=riel@redhat.com \
    --cc=torvalds@linux-foundation.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

Powered by JetHome