From: Davidlohr Bueso <davidlohr@hp.com>
To: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Ingo Molnar <mingo@elte.hu>,
Andrew Morton <akpm@linux-foundation.org>,
Andrea Arcangeli <aarcange@redhat.com>,
Alex Shi <alex.shi@linaro.org>, Andi Kleen <andi@firstfloor.org>,
Michel Lespinasse <walken@google.com>,
Davidlohr Bueso <davidlohr.bueso@hp.com>,
Matthew R Wilcox <matthew.r.wilcox@intel.com>,
Dave Hansen <dave.hansen@intel.com>,
Peter Zijlstra <a.p.zijlstra@chello.nl>,
Rik van Riel <riel@redhat.com>,
Peter Hurley <peter@hurleysoftware.com>,
linux-kernel@vger.kernel.org, linux-mm <linux-mm@kvack.org>
Subject: Re: [PATCH v5 0/6] rwsem: performance optimizations
Date: Tue, 24 Sep 2013 20:32:15 -0700 [thread overview]
Message-ID: <1380079935.2163.3.camel@buesod1.americas.hpqcorp.net> (raw)
In-Reply-To: <1380061341.3467.49.camel@schen9-DESK>
On Tue, 2013-09-24 at 15:22 -0700, Tim Chen wrote:
> We have incorporated various suggestions from Ingo for version 5 of this patchset
> and will like to have it merged if there are no objections.
>
> In this patchset, we introduce two categories of optimizations to read
> write semaphore. The first four patches from Alex Shi reduce cache bouncing of the
> sem->count field by doing a pre-read of the sem->count and avoid cmpxchg
> if possible.
>
> The last two patches introduce similar optimistic spinning logic as
> the mutex code for the writer lock acquisition of rwsem.
Right. We address the general 'mutexes out perform writer-rwsems'
situations that has been seen in more than one case. Users now need not
worry about performance issues when choosing between these two locking
mechanisms.
Thanks,
Davidlohr
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>
next prev parent reply other threads:[~2013-09-25 3:32 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <cover.1380057198.git.tim.c.chen@linux.intel.com>
2013-09-24 22:22 ` Tim Chen
2013-09-25 3:32 ` Davidlohr Bueso [this message]
2013-09-24 22:22 ` [PATCH v5 1/6] rwsem: check the lock before cpmxchg in down_write_trylock Tim Chen
2013-09-24 23:22 ` Jason Low
2013-09-24 23:30 ` Tim Chen
2013-09-24 22:22 ` [PATCH v5 2/6] rwsem: remove 'out' label in do_wake Tim Chen
2013-09-24 22:22 ` [PATCH v5 3/6] rwsem: remove try_reader_grant label do_wake Tim Chen
2013-09-24 22:22 ` [PATCH v5 4/6] rwsem/wake: check lock before do atomic update Tim Chen
2013-09-24 22:22 ` [PATCH v5 5/6] MCS Lock: Restructure the MCS lock defines and locking code into its own file Tim Chen
2013-09-25 5:55 ` Peter Zijlstra
2013-09-25 15:58 ` Tim Chen
2013-09-24 22:22 ` [PATCH v5 6/6] rwsem: do optimistic spinning for writer lock acquisition Tim Chen
2013-09-25 6:52 ` Ingo Molnar
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=1380079935.2163.3.camel@buesod1.americas.hpqcorp.net \
--to=davidlohr@hp.com \
--cc=a.p.zijlstra@chello.nl \
--cc=aarcange@redhat.com \
--cc=akpm@linux-foundation.org \
--cc=alex.shi@linaro.org \
--cc=andi@firstfloor.org \
--cc=dave.hansen@intel.com \
--cc=davidlohr.bueso@hp.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=matthew.r.wilcox@intel.com \
--cc=mingo@elte.hu \
--cc=peter@hurleysoftware.com \
--cc=riel@redhat.com \
--cc=tim.c.chen@linux.intel.com \
--cc=walken@google.com \
/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