From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-lb0-f173.google.com (mail-lb0-f173.google.com [209.85.217.173]) by kanga.kvack.org (Postfix) with ESMTP id D5DA96B0031 for ; Tue, 1 Jul 2014 20:39:18 -0400 (EDT) Received: by mail-lb0-f173.google.com with SMTP id s7so7558120lbd.32 for ; Tue, 01 Jul 2014 17:39:18 -0700 (PDT) Received: from lgeamrelo01.lge.com (lgeamrelo01.lge.com. [156.147.1.125]) by mx.google.com with ESMTP id i10si21055566laf.109.2014.07.01.17.39.15 for ; Tue, 01 Jul 2014 17:39:17 -0700 (PDT) Date: Wed, 2 Jul 2014 09:44:26 +0900 From: Joonsoo Kim Subject: Re: [PATCH v3 3/9] slab: defer slab_destroy in free_block() Message-ID: <20140702004426.GB9972@js1304-P5Q-DELUXE> References: <1404203258-8923-1-git-send-email-iamjoonsoo.kim@lge.com> <1404203258-8923-4-git-send-email-iamjoonsoo.kim@lge.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: owner-linux-mm@kvack.org List-ID: To: David Rientjes Cc: Andrew Morton , Christoph Lameter , Pekka Enberg , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Vladimir Davydov On Tue, Jul 01, 2014 at 03:25:04PM -0700, David Rientjes wrote: > On Tue, 1 Jul 2014, Joonsoo Kim wrote: > > > In free_block(), if freeing object makes new free slab and number of > > free_objects exceeds free_limit, we start to destroy this new free slab > > with holding the kmem_cache node lock. Holding the lock is useless and, > > generally, holding a lock as least as possible is good thing. I never > > measure performance effect of this, but we'd be better not to hold the lock > > as much as possible. > > > > Commented by Christoph: > > This is also good because kmem_cache_free is no longer called while > > holding the node lock. So we avoid one case of recursion. > > > > Acked-by: Christoph Lameter > > Signed-off-by: Joonsoo Kim > > Not sure what happened to my > > Acked-by: David Rientjes > > from http://marc.info/?l=linux-kernel&m=139951092124314, and for the > record, I still think the free_block() "list" formal should be commented. Really sorry about that. My mail client didn't have this mail due to unknow reason, so I missed it. Here goes the new one with applying your comment. --------->8------------