From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail203.messagelabs.com (mail203.messagelabs.com [216.82.254.243]) by kanga.kvack.org (Postfix) with ESMTP id D668F6B004D for ; Fri, 16 Oct 2009 15:07:16 -0400 (EDT) Received: from zps35.corp.google.com (zps35.corp.google.com [172.25.146.35]) by smtp-out.google.com with ESMTP id n9GJ7Cnw025795 for ; Fri, 16 Oct 2009 20:07:13 +0100 Received: from pxi36 (pxi36.prod.google.com [10.243.27.36]) by zps35.corp.google.com with ESMTP id n9GJ79dH017737 for ; Fri, 16 Oct 2009 12:07:10 -0700 Received: by pxi36 with SMTP id 36so1897072pxi.18 for ; Fri, 16 Oct 2009 12:07:09 -0700 (PDT) Date: Fri, 16 Oct 2009 12:07:07 -0700 (PDT) From: David Rientjes Subject: Re: [PATCH 2/2] page allocator: Direct reclaim should always obey watermarks In-Reply-To: <1255689446-3858-3-git-send-email-mel@csn.ul.ie> Message-ID: References: <1255689446-3858-1-git-send-email-mel@csn.ul.ie> <1255689446-3858-3-git-send-email-mel@csn.ul.ie> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org To: Mel Gorman Cc: Andrew Morton , stable , "Rafael J. Wysocki" , David Miller , Frans Pop , reinette chatre , Kalle Valo , "John W. Linville" , Pekka Enberg , Bartlomiej Zolnierkiewicz , Karol Lewandowski , netdev@vger.kernel.org, linux-kernel@vger.kernel.org, "linux-mm@kvack.org\"" List-ID: On Fri, 16 Oct 2009, Mel Gorman wrote: > ALLOC_NO_WATERMARKS should be cleared when trying to allocate from the > free-lists after a direct reclaim. If it's not, __GFP_NOFAIL allocations > from a process that is exiting can ignore watermarks. __GFP_NOFAIL is not > often used but the journal layer is one of those places. This is suspected of > causing an increase in the number of GFP_ATOMIC allocation failures reported. > > Signed-off-by: Mel Gorman > --- > mm/page_alloc.c | 3 ++- > 1 files changed, 2 insertions(+), 1 deletions(-) > > diff --git a/mm/page_alloc.c b/mm/page_alloc.c > index dfa4362..a3e5fed 100644 > --- a/mm/page_alloc.c > +++ b/mm/page_alloc.c > @@ -1860,7 +1860,8 @@ rebalance: > page = __alloc_pages_direct_reclaim(gfp_mask, order, > zonelist, high_zoneidx, > nodemask, > - alloc_flags, preferred_zone, > + alloc_flags & ~ALLOC_NO_WATERMARKS, > + preferred_zone, > migratetype, &did_some_progress); > if (page) > goto got_pg; I don't get it. __alloc_pages_high_priority() will already loop indefinitely if ALLOC_NO_WATERMARKS is set and its a __GFP_NOFAIL allocation. How do we even reach this code in such a condition? -- 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