From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pa0-f71.google.com (mail-pa0-f71.google.com [209.85.220.71]) by kanga.kvack.org (Postfix) with ESMTP id 6FB80280250 for ; Fri, 7 Oct 2016 05:21:12 -0400 (EDT) Received: by mail-pa0-f71.google.com with SMTP id gg9so22583831pac.6 for ; Fri, 07 Oct 2016 02:21:12 -0700 (PDT) Received: from mail-pf0-f193.google.com (mail-pf0-f193.google.com. [209.85.192.193]) by mx.google.com with ESMTPS id e191si7867887pfg.108.2016.10.07.02.21.11 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 07 Oct 2016 02:21:11 -0700 (PDT) Received: by mail-pf0-f193.google.com with SMTP id 190so2577833pfv.1 for ; Fri, 07 Oct 2016 02:21:11 -0700 (PDT) Date: Fri, 7 Oct 2016 11:21:08 +0200 From: Michal Hocko Subject: Re: [RFC PATCH] mm, compaction: allow compaction for GFP_NOFS requests Message-ID: <20161007092107.GJ18439@dhcp22.suse.cz> References: <20161004081215.5563-1-mhocko@kernel.org> <20161007065019.GA18439@dhcp22.suse.cz> 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: Vlastimil Babka Cc: Mel Gorman , Joonsoo Kim , Andrew Morton , linux-mm@kvack.org, LKML On Fri 07-10-16 10:15:07, Vlastimil Babka wrote: > On 10/07/2016 08:50 AM, Michal Hocko wrote: > > On Fri 07-10-16 07:27:37, Vlastimil Babka wrote: [...] > > > But make sure you don't break kcompactd and manual compaction from /proc, as > > > they don't currently set cc->gfp_mask. Looks like until now it was only used > > > to determine direct compactor's migratetype which is irrelevant in those > > > contexts. > > > > OK, I see. This is really subtle. One way to go would be to provide a > > fake gfp_mask for them. How does the following look to you? > > Looks OK. I'll have to think about the kcompactd case, as gfp mask implying > unmovable migratetype might restrict it without good reason. But that would > be separate patch anyway, yours doesn't change that (empty gfp_mask also > means unmovable migratetype) and that's good. OK, I see. A follow up patch would be really trivial AFAICS. Just add __GFP_MOVABLE to the mask. But I am not familiar with all these details enough to propose a patch with full description. -- Michal Hocko SUSE Labs -- 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