From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756208Ab2J2BrQ (ORCPT ); Sun, 28 Oct 2012 21:47:16 -0400 Received: from LGEMRELSE1Q.lge.com ([156.147.1.111]:47743 "EHLO LGEMRELSE1Q.lge.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751907Ab2J2BrP (ORCPT ); Sun, 28 Oct 2012 21:47:15 -0400 X-AuditID: 9c93016f-b7c7bae000000eb7-9a-508de0206887 Date: Mon, 29 Oct 2012 10:52:59 +0900 From: Minchan Kim To: Joonsoo Kim Cc: Andrew Morton , linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: Re: [PATCH 2/5] mm, highmem: remove useless pool_lock Message-ID: <20121029015259.GG15767@bbox> References: <1351451576-2611-1-git-send-email-js1304@gmail.com> <1351451576-2611-3-git-send-email-js1304@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1351451576-2611-3-git-send-email-js1304@gmail.com> User-Agent: Mutt/1.5.21 (2010-09-15) X-Brightmail-Tracker: AAAAAA== Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Oct 29, 2012 at 04:12:53AM +0900, Joonsoo Kim wrote: > The pool_lock protects the page_address_pool from concurrent access. > But, access to the page_address_pool is already protected by kmap_lock. > So remove it. > > Signed-off-by: Joonsoo Kim Reviewed-by: Minchan Kin Looks good to me. Just a nitpick. Please write comment about locking rule like below. > > diff --git a/mm/highmem.c b/mm/highmem.c > index b3b3d68..017bad1 100644 > --- a/mm/highmem.c > +++ b/mm/highmem.c > @@ -328,7 +328,6 @@ struct page_address_map { > * page_address_map freelist, allocated from page_address_maps. > */ /* page_address_pool is protected by kmap_lock */ > static struct list_head page_address_pool; /* freelist */ > -static spinlock_t pool_lock; /* protects page_address_pool */ > -- Kind regards, Minchan Kim