linux-kernel - Re: [PATCH v7 1/4] spinlock: A new lockref structure for lockless update of refcount

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Wed, 4 Sep 2013 00:41:29 +0200
From:	Sedat Dilek <sedat.dilek@...il.com>
To:	Waiman Long <waiman.long@...com>
Cc:	Ingo Molnar <mingo@...nel.org>, Al Viro <viro@...iv.linux.org.uk>,
	Linus Torvalds <torvalds@...ux-foundation.org>,
	Benjamin Herrenschmidt <benh@...nel.crashing.org>,
	Jeff Layton <jlayton@...hat.com>,
	Miklos Szeredi <mszeredi@...e.cz>,
	Ingo Molnar <mingo@...hat.com>,
	Thomas Gleixner <tglx@...utronix.de>,
	linux-fsdevel <linux-fsdevel@...r.kernel.org>,
	Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
	Peter Zijlstra <peterz@...radead.org>,
	Steven Rostedt <rostedt@...dmis.org>,
	Andi Kleen <andi@...stfloor.org>,
	"Chandramouleeswaran, Aswin" <aswin@...com>,
	"Norton, Scott J" <scott.norton@...com>
Subject: Re: [PATCH v7 1/4] spinlock: A new lockref structure for lockless
 update of refcount

On Tue, Sep 3, 2013 at 5:14 PM, Waiman Long <waiman.long@...com> wrote:
> On 09/03/2013 02:01 AM, Ingo Molnar wrote:
>>
>> * Waiman Long<waiman.long@...com>  wrote:
>>
>>> Yes, that patch worked. It eliminated the lglock as a bottleneck in the
>>> AIM7 workload. The lg_global_lock did not show up in the perf profile,
>>> whereas the lg_local_lock was only 0.07%.
>>
>> Just curious: what's the worst bottleneck now in the optimized kernel? :-)
>>
>> Thanks,
>>
>>         Ingo
>
> With the following patches on v3.11:
> 1. Linus's version of lockref patch
> 2. Al's lglock patch
> 3. My preliminary patch to convert prepend_path under RCU
>

With no reference where to get those patches, it's a bit hard to follow.

I will try some perf benchmarking with the attached patch against
Linux "WfW" edition.

- Sedat -

Download attachment "3.11.0-1-lockref-small.patch" of type "application/octet-stream" (15845 bytes)