From mboxrd@z Thu Jan 1 00:00:00 1970 From: Peter Zijlstra Subject: Re: [patch 03/33] fs: scale files_lock Date: Mon, 28 Sep 2009 15:24:08 +0200 Message-ID: <1254144248.15795.6.camel@laptop> References: <20090904065142.114706411@nick.local0.net> <20090904065534.303326352@nick.local0.net> Mime-Version: 1.0 Content-Type: text/plain Content-Transfer-Encoding: 7bit Cc: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org To: npiggin@suse.de Return-path: In-Reply-To: <20090904065534.303326352@nick.local0.net> Sender: linux-kernel-owner@vger.kernel.org List-Id: linux-fsdevel.vger.kernel.org On Fri, 2009-09-04 at 16:51 +1000, npiggin@suse.de wrote: > Improve scalability of files_lock by adding per-cpu, per-sb files lists, > protected with per-cpu locking. Effectively turning it into a big-writer > lock. What I did was fine-grain locking the double linked list so that you can delete items without hitting a global lock. For addition I added per-cpu list-heads that would be spliced onto the global list once in a while. Granted, the code was a tad involved... and hch wanted to get rid of these lists, which is of course a much better solution.