From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932500AbcBAUnd (ORCPT ); Mon, 1 Feb 2016 15:43:33 -0500 Received: from mga14.intel.com ([192.55.52.115]:64090 "EHLO mga14.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932096AbcBAUnc (ORCPT ); Mon, 1 Feb 2016 15:43:32 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.22,381,1449561600"; d="scan'208";a="894059376" Date: Mon, 1 Feb 2016 15:43:35 -0500 From: Matthew Wilcox To: "Kirill A. Shutemov" Cc: Matthew Wilcox , Andrew Morton , linux-mm@kvack.org, linux-nvdimm@ml01.01.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 4/6] dax: Use PAGE_CACHE_SIZE where appropriate Message-ID: <20160201204335.GE2948@linux.intel.com> References: <1454242795-18038-1-git-send-email-matthew.r.wilcox@intel.com> <1454242795-18038-5-git-send-email-matthew.r.wilcox@intel.com> <20160201131019.GC29337@node.shutemov.name> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20160201131019.GC29337@node.shutemov.name> User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Feb 01, 2016 at 03:10:19PM +0200, Kirill A. Shutemov wrote: > On Sun, Jan 31, 2016 at 11:19:53PM +1100, Matthew Wilcox wrote: > > We were a little sloppy about using PAGE_SIZE instead of PAGE_CACHE_SIZE. > > PAGE_CACHE_SIZE is non-sense. It never had any meaning. At least in > upstream. And only leads to confusion on border between vfs and mm. > > We should just drop it. > > I need to find time at some point to prepare patchset... I argued in favour of this at last LSFMM and people were ... reluctant. I think with your map_pages work, the PAGE_CACHE_SIZE idea now has no potential performance win left.