From mboxrd@z Thu Jan 1 00:00:00 1970 From: Johannes Weiner Subject: Re: mmotm 2015-01-22-15-04: qemu failure due to 'mm: memcontrol: remove unnecessary soft limit tree node test' Date: Sat, 24 Jan 2015 02:16:23 -0500 Message-ID: <20150124071623.GA17705@phnom.home.cmpxchg.org> References: <54c1822d.RtdGfWPekQVAw8Ly%akpm@linux-foundation.org> <20150123050802.GB22751@roeck-us.net> <20150123141817.GA22926@phnom.home.cmpxchg.org> <54C2B01D.4070303@roeck-us.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Guenter Roeck , akpm@linux-foundation.org, mm-commits@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-fsdevel@vger.kernel.org, linux-next@vger.kernel.org, sfr@canb.auug.org.au, mhocko@suse.cz To: Christoph Lameter Return-path: Content-Disposition: inline In-Reply-To: Sender: owner-linux-mm@kvack.org List-Id: linux-fsdevel.vger.kernel.org On Fri, Jan 23, 2015 at 03:09:20PM -0600, Christoph Lameter wrote: > On Fri, 23 Jan 2015, Guenter Roeck wrote: > > > Wouldn't that have unintended consequences ? So far > > rb tree nodes are allocated even if a node not online; > > the above would change that. Are you saying it is > > unnecessary to initialize rb tree nodes if the node > > is not online ? > > It is not advisable to allocate since an offline node means that the > structure cannot be allocated on the node where it would be most > beneficial. Typically subsystems allocate the per node data structures > when the node is brought online. I would generally agree, but this code, which implements a userspace interface, is already grotesquely inefficient and heavyhanded. It's also superseded in the next release, so we can just keep this simple at this point. -- 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