From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757449AbcJZS3w (ORCPT ); Wed, 26 Oct 2016 14:29:52 -0400 Received: from gum.cmpxchg.org ([85.214.110.215]:44638 "EHLO gum.cmpxchg.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932196AbcJZS3u (ORCPT ); Wed, 26 Oct 2016 14:29:50 -0400 Date: Wed, 26 Oct 2016 14:29:42 -0400 From: Johannes Weiner To: Linus Torvalds Cc: Andrew Morton , Jan Kara , Dave Jones , linux-mm , Linux Kernel Mailing List , kernel-team Subject: Re: [PATCH 0/5] mm: workingset: radix tree subtleties & single-page file refaults Message-ID: <20161026182942.GA18258@cmpxchg.org> References: <20161019172428.7649-1-hannes@cmpxchg.org> <20161024184739.GB2125@cmpxchg.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.7.1 (2016-10-04) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Oct 26, 2016 at 11:18:52AM -0700, Linus Torvalds wrote: > On Mon, Oct 24, 2016 at 11:47 AM, Johannes Weiner wrote: > > > > How about this instead: given that we already mark the shadow entries > > exceptional, and the exceptional bit is part of the radix tree API, > > can we just introduce a node->exceptional counter for those entries > > and have the radix tree code assist us with that instead? It adds the > > counting for non-shadow exceptional entries as well (shmem swap slots, > > and DAX non-page entries), unfortunately, but this is way cleaner. It > > also makes mapping->nrexceptional and node->exceptional consistent in > > DAX (Jan, could you please double check the accounting there?) > > > > What do you think? Lightly tested patch below. > > This certainly looks way better to me. I didn't *test* it, but it > doesn't make me scratch my head the way your previous patch did. Awesome, thanks. I'll continue to beat on this for a while and then send it on to Andrew.