From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail137.messagelabs.com (mail137.messagelabs.com [216.82.249.19]) by kanga.kvack.org (Postfix) with SMTP id 36FDE6B009F for ; Sun, 19 Dec 2010 20:59:12 -0500 (EST) Received: from m1.gw.fujitsu.co.jp ([10.0.50.71]) by fgwmail5.fujitsu.co.jp (Fujitsu Gateway) with ESMTP id oBK1x9x7007177 for (envelope-from kamezawa.hiroyu@jp.fujitsu.com); Mon, 20 Dec 2010 10:59:09 +0900 Received: from smail (m1 [127.0.0.1]) by outgoing.m1.gw.fujitsu.co.jp (Postfix) with ESMTP id DE77E45DE5B for ; Mon, 20 Dec 2010 10:59:08 +0900 (JST) Received: from s1.gw.fujitsu.co.jp (s1.gw.fujitsu.co.jp [10.0.50.91]) by m1.gw.fujitsu.co.jp (Postfix) with ESMTP id C5C9A45DE5A for ; Mon, 20 Dec 2010 10:59:08 +0900 (JST) Received: from s1.gw.fujitsu.co.jp (localhost.localdomain [127.0.0.1]) by s1.gw.fujitsu.co.jp (Postfix) with ESMTP id B8A85E08006 for ; Mon, 20 Dec 2010 10:59:08 +0900 (JST) Received: from m106.s.css.fujitsu.com (m106.s.css.fujitsu.com [10.249.87.106]) by s1.gw.fujitsu.co.jp (Postfix) with ESMTP id 83C0CE08002 for ; Mon, 20 Dec 2010 10:59:08 +0900 (JST) Date: Mon, 20 Dec 2010 10:53:22 +0900 From: KAMEZAWA Hiroyuki Subject: Re: [RFC 1/5] drop page reference on remove_from_page_cache Message-Id: <20101220105322.3b0dba88.kamezawa.hiroyu@jp.fujitsu.com> In-Reply-To: <4bd059fc4f45fba7ed29a9f4325deb4f437d39f3.1292604745.git.minchan.kim@gmail.com> References: <4bd059fc4f45fba7ed29a9f4325deb4f437d39f3.1292604745.git.minchan.kim@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org To: Minchan Kim Cc: Andrew Morton , linux-mm , LKML , Hugh Dickins List-ID: On Sat, 18 Dec 2010 02:13:36 +0900 Minchan Kim wrote: > Now we add page reference on add_to_page_cache but doesn't drop it > in remove_from_page_cache. Such asymmetric makes confusing about > page reference so that caller should notice it and comment why they > release page reference. It's not good API. > > Long time ago, Hugh tried it[1] but gave up of reason which > reiser4's drop_page had to unlock the page between removing it from > page cache and doing the page_cache_release. But now the situation is > changed. I think at least things in current mainline doesn't have any > obstacles. The problem is fs or somethings out of mainline. > If it has done such thing like reiser4, this patch could be a problem. > > Do anyone know the such things? Do we care about things out of mainline? > > Note : > The comment of remove_from_page_cache make by copy & paste & s/swap/page/ > from delete_from_swap_cache. > > [1] http://lkml.org/lkml/2004/10/24/140 > > Cc: Hugh Dickins > Cc: linux-mm@kvack.org > Signed-off-by: Minchan Kim I like this. Reviewd-by: KAMEZAWA Hiroyuki -- 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/ . Fight unfair telecom policy in Canada: sign http://dissolvethecrtc.ca/ Don't email: email@kvack.org