From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <48468343.2010006@firstfloor.org> Date: Wed, 04 Jun 2008 13:57:55 +0200 From: Andi Kleen MIME-Version: 1.0 Subject: Re: [patch 00/21] hugetlb multi size, giant hugetlb support, etc References: <20080603095956.781009952@amd.local0.net> <20080604012938.53b1003c.akpm@linux-foundation.org> In-Reply-To: <20080604012938.53b1003c.akpm@linux-foundation.org> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: Andrew Morton Cc: npiggin@suse.de, Nishanth Aravamudan , linux-mm@kvack.org, kniht@us.ibm.com, abh@cray.com, joachim.deguara@amd.com List-ID: > : Large, but rather mechanical patch that converts most of the hugetlb.c > : globals into structure members and passes them around. > : > : Right now there is only a single global hstate structure, but > : most of the infrastructure to extend it is there. > > OK, but it didn't tell us why we want multiple hstate structures. > > : Add basic support for more than one hstate in hugetlbfs > : > : - Convert hstates to an array > : - Add a first default entry covering the standard huge page size > : - Add functions for architectures to register new hstates > : - Add basic iterators over hstates > > And neither did that. > > One for each hugepage size, I'd guess. > > : Add support to have individual hstates for each hugetlbfs mount > : > : - Add a new pagesize= option to the hugetlbfs mount that allows setting > : the page size > : - Set up pointers to a suitable hstate for the set page size option > : to the super block and the inode and the vma. > : - Change the hstate accessors to use this information > : - Add code to the hstate init function to set parsed_hstate for command > : line processing > : - Handle duplicated hstate registrations to the make command line user proof > > Nope, wrong guess. It's one per mountpoint. No the initial guess was correct. It's one per size. > > So now I'm seeing (I think) that the patchset does indeed implement > multiple page-size hugepages, and that it it does this by making an > entire hugetlb mountpoint have a single-but-settable pagesize. Correct. > > All pretty straightforward stuff, unless I'm missing something. But > please do spell it out because surely there's stuff in here which I > will miss from the implementation and the skimpy changelog. It was spelled out in the original 0/0 Here's a copy ftp://ftp.firstfloor.org/pub/ak/gbpages/patches/intro > Please don't think I'm being anal here - changelogging matters. It > makes review more effective and it allows reviewers to find problems > which they would otherwise have overlooked. btdt, lots of times. Hmm, perhaps we need dummy commits for 0/0s. I guess the intro could be added to the changelog of the first patch. -Andi -- 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