From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from westrelay02.boulder.ibm.com (westrelay02.boulder.ibm.com [9.17.195.11]) by e36.co.us.ibm.com (8.12.11/8.12.11) with ESMTP id j8R0NGfJ005988 for ; Mon, 26 Sep 2005 20:23:16 -0400 Received: from d03av01.boulder.ibm.com (d03av01.boulder.ibm.com [9.17.195.167]) by westrelay02.boulder.ibm.com (8.12.10/NCO/VERS6.7) with ESMTP id j8R0OPrJ187524 for ; Mon, 26 Sep 2005 18:24:25 -0600 Received: from d03av01.boulder.ibm.com (loopback [127.0.0.1]) by d03av01.boulder.ibm.com (8.12.11/8.13.3) with ESMTP id j8R0OOeg003883 for ; Mon, 26 Sep 2005 18:24:25 -0600 Subject: Re: [PATCH 1/9] add defrag flags From: Dave Hansen In-Reply-To: <21024267-29C3-4657-9C45-17D186EAD808@mac.com> References: <4338537E.8070603@austin.ibm.com> <43385412.5080506@austin.ibm.com> <21024267-29C3-4657-9C45-17D186EAD808@mac.com> Content-Type: text/plain Date: Mon, 26 Sep 2005 17:24:08 -0700 Message-Id: <1127780648.10315.12.camel@localhost> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: Kyle Moffett Cc: Joel Schopp , Andrew Morton , lhms , Linux Memory Management List , Linux Kernel Mailing List , Mel Gorman , Mike Kravetz List-ID: On Mon, 2005-09-26 at 20:16 -0400, Kyle Moffett wrote: > On Sep 26, 2005, at 16:03:30, Joel Schopp wrote: > > The flags are: > > __GFP_USER, which corresponds to easily reclaimable pages > > __GFP_KERNRCLM, which corresponds to userspace pages > > Uhh, call me crazy, but don't those flags look a little backwards to > you? Maybe it's just me, but wouldn't it make sense to expect > __GFP_USER to be a userspace allocation and __GFP_KERNRCLM to be an > easily reclaimable kernel page? I think Joel simply made an error in his description. __GFP_KERNRCLM corresponds to pages which are kernel-allocated, but have some chance of being reclaimed at some point. Basically, they're things that will get freed back under memory pressure. This can be direct, as with the dcache and its slab shrinker, or more indirect as for control structures like buffer_heads that get reclaimed after _other_ things are freed. -- Dave -- 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