From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pa0-f42.google.com (mail-pa0-f42.google.com [209.85.220.42]) by kanga.kvack.org (Postfix) with ESMTP id 0D0DB6B0031 for ; Sun, 9 Feb 2014 20:21:56 -0500 (EST) Received: by mail-pa0-f42.google.com with SMTP id kl14so5506751pab.15 for ; Sun, 09 Feb 2014 17:21:56 -0800 (PST) Received: from LGEAMRELO01.lge.com (lgeamrelo01.lge.com. [156.147.1.125]) by mx.google.com with ESMTP id i8si13295367pav.335.2014.02.09.17.21.55 for ; Sun, 09 Feb 2014 17:21:56 -0800 (PST) Date: Mon, 10 Feb 2014 10:22:03 +0900 From: Joonsoo Kim Subject: Re: [RFC PATCH 3/3] slub: fallback to get_numa_mem() node if we want to allocate on memoryless node Message-ID: <20140210012203.GC12574@lge.com> References: <20140206020757.GC5433@linux.vnet.ibm.com> <1391674026-20092-1-git-send-email-iamjoonsoo.kim@lge.com> <1391674026-20092-3-git-send-email-iamjoonsoo.kim@lge.com> <20140207054119.GA28952@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: Christoph Lameter Cc: Nishanth Aravamudan , David Rientjes , Han Pingtian , penberg@kernel.org, linux-mm@kvack.org, paulus@samba.org, Anton Blanchard , mpm@selenic.com, linuxppc-dev@lists.ozlabs.org, Wanpeng Li On Fri, Feb 07, 2014 at 11:49:57AM -0600, Christoph Lameter wrote: > On Fri, 7 Feb 2014, Joonsoo Kim wrote: > > > > This check wouild need to be something that checks for other contigencies > > > in the page allocator as well. A simple solution would be to actually run > > > a GFP_THIS_NODE alloc to see if you can grab a page from the proper node. > > > If that fails then fallback. See how fallback_alloc() does it in slab. > > > > > > > Hello, Christoph. > > > > This !node_present_pages() ensure that allocation on this node cannot succeed. > > So we can directly use numa_mem_id() here. > > Yes of course we can use numa_mem_id(). > > But the check is only for not having any memory at all on a node. There > are other reason for allocations to fail on a certain node. The node could > have memory that cannot be reclaimed, all dirty, beyond certain > thresholds, not in the current set of allowed nodes etc etc. Yes. There are many other cases, but I prefer that we think them separately. Maybe they needs another approach. For now, to solve memoryless node problem, my solution is enough and safe. Thanks. -- 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