From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-ig0-f177.google.com (mail-ig0-f177.google.com [209.85.213.177]) by kanga.kvack.org (Postfix) with ESMTP id A487F6B0005 for ; Wed, 30 Mar 2016 04:25:03 -0400 (EDT) Received: by mail-ig0-f177.google.com with SMTP id cl4so95440917igb.0 for ; Wed, 30 Mar 2016 01:25:03 -0700 (PDT) Received: from lgeamrelo13.lge.com (LGEAMRELO13.lge.com. [156.147.23.53]) by mx.google.com with ESMTP id c6si18267325igx.58.2016.03.30.01.25.02 for ; Wed, 30 Mar 2016 01:25:03 -0700 (PDT) Date: Wed, 30 Mar 2016 17:27:02 +0900 From: Joonsoo Kim Subject: Re: [PATCH v2 2/2] mm: rename _count, field of the struct page, to _refcount Message-ID: <20160330082701.GG1678@js1304-P5Q-DELUXE> References: <1459146601-11448-1-git-send-email-iamjoonsoo.kim@lge.com> <1459146601-11448-2-git-send-email-iamjoonsoo.kim@lge.com> <56FA4A93.6090502@suse.cz> <20160329122313.3c24964faab99f46c960b19b@linux-foundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20160329122313.3c24964faab99f46c960b19b@linux-foundation.org> Sender: owner-linux-mm@kvack.org List-ID: To: Andrew Morton Cc: Vlastimil Babka , Hugh Dickins , Johannes Berg , "David S. Miller" , Sunil Goutham , Chris Metcalf , linux-mm@kvack.org, linux-kernel@vger.kernel.org On Tue, Mar 29, 2016 at 12:23:13PM -0700, Andrew Morton wrote: > On Tue, 29 Mar 2016 11:27:47 +0200 Vlastimil Babka wrote: > > > > v2: change more _count usages to _refcount > > > > There's also > > Documentation/vm/transhuge.txt talking about ->_count > > include/linux/mm.h: * requires to already have an elevated page->_count. > > include/linux/mm_types.h: * Keep _count separate from slub cmpxchg_double data. > > include/linux/mm_types.h: * slab_lock but _count is not. > > include/linux/pagemap.h: * If the page is free (_count == 0), then _count is untouched, and 0 > > include/linux/pagemap.h: * is returned. Otherwise, _count is incremented by 1 and 1 is returned. > > include/linux/pagemap.h: * this allows allocators to use a synchronize_rcu() to stabilize _count. > > include/linux/pagemap.h: * Remove-side that cares about stability of _count (eg. reclaim) has the > > mm/huge_memory.c: * tail_page->_count is zero and not changing from under us. But > > mm/huge_memory.c: /* Prevent deferred_split_scan() touching ->_count */ > > mm/internal.h: * Turn a non-refcounted page (->_count == 0) into refcounted with > > mm/page_alloc.c: bad_reason = "nonzero _count"; > > mm/page_alloc.c: bad_reason = "nonzero _count"; > > mm/page_alloc.c: * because their page->_count is zero at all time. > > mm/slub.c: * as page->_count. If we assign to ->counters directly > > mm/slub.c: * we run the risk of losing updates to page->_count, so > > mm/vmscan.c: * load is not satisfied before that of page->_count. > > mm/vmscan.c: * The downside is that we have to touch page->_count against each page. > > > > I've arrived at the following command to find this: > > git grep "[^a-zA-Z0-9_]_count[^_]" > > > > Not that many false positives in the output :) > > > From: Andrew Morton > Subject: mm-rename-_count-field-of-the-struct-page-to-_refcount-fix > > fix comments, per Vlastimil Andrew and Vlastimil, great thanks! Thanks. -- 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