From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754811AbaESOin (ORCPT ); Mon, 19 May 2014 10:38:43 -0400 Received: from bombadil.infradead.org ([198.137.202.9]:59012 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754587AbaESOim (ORCPT ); Mon, 19 May 2014 10:38:42 -0400 Date: Mon, 19 May 2014 07:38:37 -0700 From: Christoph Hellwig To: "Kirill A. Shutemov" Cc: Kenny Simpson , Michal Hocko , linux-kernel@vger.kernel.org, Andrew Morton , Peter Zijlstra , Dave Jones , Linus Torvalds , Armin Rigo Subject: Re: remap_file_pages() use Message-ID: <20140519143837.GA5228@infradead.org> References: <20140519130114.GA3140@dhcp22.suse.cz> <20140519143540.BE9F6E009B@blue.fi.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20140519143540.BE9F6E009B@blue.fi.intel.com> User-Agent: Mutt/1.5.21 (2010-09-15) X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, May 19, 2014 at 05:35:40PM +0300, Kirill A. Shutemov wrote: > >From functional POV, emulation *should* be identical to original > remap_file_pages(), but slower. It would be nice, if you test it early. > > It's not clear yet how long emulation will be there. Stop right there. We found out about two real life users of remap_file_pages() already, without even committing the patches to warn about using it to any tree. I think at this point the whole idea of removing the API should be dead on the floor, as we do not needlessly break userspace programs. If we can get rid of the ugly guts and provide a good enough emulation that the user won't cry I'd love to get rid of this cruft, but even that doesn't look certain yet.