From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail203.messagelabs.com (mail203.messagelabs.com [216.82.254.243]) by kanga.kvack.org (Postfix) with ESMTP id C835B6B0098 for ; Thu, 11 Nov 2010 02:51:03 -0500 (EST) Received: from hpaq5.eem.corp.google.com (hpaq5.eem.corp.google.com [172.25.149.5]) by smtp-out.google.com with ESMTP id oAB7p0Ax000830 for ; Wed, 10 Nov 2010 23:51:00 -0800 Received: from pxi16 (pxi16.prod.google.com [10.243.27.16]) by hpaq5.eem.corp.google.com with ESMTP id oAB7oqaJ009096 for ; Wed, 10 Nov 2010 23:50:59 -0800 Received: by pxi16 with SMTP id 16so372699pxi.32 for ; Wed, 10 Nov 2010 23:50:57 -0800 (PST) Date: Wed, 10 Nov 2010 23:50:54 -0800 (PST) From: David Rientjes Subject: Re: [PATCH v3] fix __set_page_dirty_no_writeback() return value In-Reply-To: <1289445963-29664-1-git-send-email-lliubbo@gmail.com> Message-ID: References: <1289445963-29664-1-git-send-email-lliubbo@gmail.com> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org To: Bob Liu Cc: Andrew Morton , Wu Fengguang , linux-mm@kvack.org, Ken Chen List-ID: On Thu, 11 Nov 2010, Bob Liu wrote: > __set_page_dirty_no_writeback() should return true if it actually transitioned > the page from a clean to dirty state although it seems nobody used its return > value now. > > Change from v2: > * use TestSet to avoid racing > > Change from v1: > * preserving cacheline optimisation as Andrew pointed out > > Signed-off-by: Bob Liu > --- > mm/page-writeback.c | 2 +- > 1 files changed, 1 insertions(+), 1 deletions(-) > > diff --git a/mm/page-writeback.c b/mm/page-writeback.c > index bf85062..1ebfb86 100644 > --- a/mm/page-writeback.c > +++ b/mm/page-writeback.c > @@ -1158,7 +1158,7 @@ EXPORT_SYMBOL(write_one_page); > int __set_page_dirty_no_writeback(struct page *page) > { > if (!PageDirty(page)) > - SetPageDirty(page); > + return !TestSetPageDirty(page); > return 0; > } No need for a conditional, just return !TestSetPageDirty(page). -- 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