From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from ipmail06.adl2.internode.on.net ([150.101.137.129]:39368 "EHLO ipmail06.adl2.internode.on.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932525AbcIYVp0 (ORCPT ); Sun, 25 Sep 2016 17:45:26 -0400 Date: Mon, 26 Sep 2016 07:45:24 +1000 From: Dave Chinner Subject: Re: [PATCH] mm: remove unnecessary rcu_lock/unlock around radix_tree_tagged lockless function. The function queue_delayed_work is already protected with interrupts disabled, hence no need to add rcu_lock/unlock. Message-ID: <20160925214524.GS340@dastard> References: <20160925192005.GA6517@sudip-Dell-System-Vostro-3450> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20160925192005.GA6517@sudip-Dell-System-Vostro-3450> Sender: linux-xfs-owner@vger.kernel.org List-ID: List-Id: xfs To: Sudip Midya Cc: xfs@oss.sgi.com, hch@infradead.org, linux-xfs@vger.kernel.org On Mon, Sep 26, 2016 at 12:50:06AM +0530, Sudip Midya wrote: > Signed-off-by: Sudip Midya > --- Patch format still needs work. The subject line should be short, the patch description should be in the body of the message, not the subject. Also, this is not a patch for the "mm" subsystem. Addressing the reason given for the change: the RCU lock is not actually protecting queue_delayed_work(), so while the code change may be OK, the reason given for removing it is not. So why is it safe to remove the rcu_read_lock()? Cheers, Dave. -- Dave Chinner david@fromorbit.com