From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-qa0-f49.google.com (mail-qa0-f49.google.com [209.85.216.49]) by kanga.kvack.org (Postfix) with ESMTP id D4D796B0036 for ; Fri, 7 Feb 2014 12:50:02 -0500 (EST) Received: by mail-qa0-f49.google.com with SMTP id w8so5702211qac.36 for ; Fri, 07 Feb 2014 09:50:02 -0800 (PST) Received: from qmta14.emeryville.ca.mail.comcast.net (qmta14.emeryville.ca.mail.comcast.net. [2001:558:fe2d:44:76:96:27:212]) by mx.google.com with ESMTP id e9si4063297qas.29.2014.02.07.09.50.00 for ; Fri, 07 Feb 2014 09:50:01 -0800 (PST) Date: Fri, 7 Feb 2014 11:49:57 -0600 (CST) From: Christoph Lameter Subject: Re: [RFC PATCH 3/3] slub: fallback to get_numa_mem() node if we want to allocate on memoryless node In-Reply-To: <20140207054119.GA28952@lge.com> Message-ID: 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> Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org List-ID: To: Joonsoo Kim 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, 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. -- 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