From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <4321A8EE.9080206@yahoo.com.au> Date: Sat, 10 Sep 2005 01:23:26 +1000 From: Nick Piggin MIME-Version: 1.0 Subject: Re: [PATCH 2.6.13] lockless pagecache 7/7 References: <4317F071.1070403@yahoo.com.au> <4317F0F9.1080602@yahoo.com.au> <4317F136.4040601@yahoo.com.au> <4317F17F.5050306@yahoo.com.au> <4317F1A2.8030605@yahoo.com.au> <4317F1BD.8060808@yahoo.com.au> <4317F1E2.7030608@yahoo.com.au> <4317F203.7060109@yahoo.com.au> In-Reply-To: Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: Christoph Lameter Cc: Linux Memory Management , linux-kernel List-ID: Christoph Lameter wrote: > For Itanium (and I guess also for ppc64 and sparch64) the performance of > write_lock/unlock is the same as spin_lock/unlock. There is at least > one case where concurrent reads would be allowed without this patch. > Yep, I picked up another one that was easy to make lockless (I'll send out a new patchset soon), however the tagged lookup that was under read lock is changed to a spin lock. It shouldn't be too difficult to make the tag lookups (find_get_pages_tag) lockless, however I just haven't gotten around to looking at the write side of the tagging yet. When that is done, there should be no more read locks at all. Nick -- SUSE Labs, Novell Inc. Send instant messages to your online friends http://au.messenger.yahoo.com -- 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: email@kvack.org