From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail144.messagelabs.com (mail144.messagelabs.com [216.82.254.51]) by kanga.kvack.org (Postfix) with SMTP id 38AD06B004F for ; Fri, 17 Jul 2009 08:41:05 -0400 (EDT) Date: Fri, 17 Jul 2009 13:41:04 +0100 (BST) From: Hugh Dickins Subject: Re: [PATCH] page-allocator: Ensure that processes that have been OOM killed exit the page allocator (resend) In-Reply-To: Message-ID: References: <20090715104944.GC9267@csn.ul.ie> <20090716110328.GB22499@csn.ul.ie> <20090717092157.GA9835@csn.ul.ie> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org To: David Rientjes Cc: Mel Gorman , Andrew Morton , Nick Piggin , linux-kernel@vger.kernel.org, linux-mm@kvack.org List-ID: On Fri, 17 Jul 2009, David Rientjes wrote: > On Fri, 17 Jul 2009, Mel Gorman wrote: > > > Ok, lets go with this patch then. Thanks > > > > Ok, thanks, I'll add that as your acked-by and I'll write a formal patch > description for it. > > > mm: avoid endless looping for oom killed tasks > > If a task is oom killed and still cannot find memory when trying with no > watermarks, it's better to fail the allocation attempt than to loop > endlessly. Direct reclaim has already failed and the oom killer will be a > no-op since current has yet to die, so there is no other alternative for > allocations that are not __GFP_NOFAIL. > > Acked-by: Mel Gorman > Signed-off-by: David Rientjes This works much better for me than earlier variants (I'm needing to worry about OOM when KSM has a lot of pages to break COW on; but a large mlock is a good test) - thanks. Acked-by: Hugh Dickins > --- > diff --git a/mm/page_alloc.c b/mm/page_alloc.c > --- a/mm/page_alloc.c > +++ b/mm/page_alloc.c > @@ -1789,6 +1789,10 @@ rebalance: > if (p->flags & PF_MEMALLOC) > goto nopage; > > + /* Avoid allocations with no watermarks from looping endlessly */ > + if (test_thread_flag(TIF_MEMDIE) && !(gfp_mask & __GFP_NOFAIL)) > + goto nopage; > + > /* Try direct reclaim and then allocating */ > page = __alloc_pages_direct_reclaim(gfp_mask, order, > zonelist, high_zoneidx, -- 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