From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751853AbaHROlP (ORCPT ); Mon, 18 Aug 2014 10:41:15 -0400 Received: from mail-lb0-f170.google.com ([209.85.217.170]:58606 "EHLO mail-lb0-f170.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751118AbaHROlO (ORCPT ); Mon, 18 Aug 2014 10:41:14 -0400 Date: Mon, 18 Aug 2014 17:41:01 +0300 From: Andreea-Cristina Bernat To: willy@linux.intel.com, linux-nvme@lists.infradead.org, linux-kernel@vger.kernel.org Cc: paulmck@linux.vnet.ibm.com Subject: [PATCH] nvme: Replace rcu_assign_pointer() with RCU_INIT_POINTER() Message-ID: <20140818144101.GA13840@ada> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The use of "rcu_assign_pointer()" is NULLing out the pointer. According to RCU_INIT_POINTER()'s block comment: "1. This use of RCU_INIT_POINTER() is NULLing out the pointer" it is better to use it instead of rcu_assign_pointer() because it has a smaller overhead. The following Coccinelle semantic patch was used: @@ @@ - rcu_assign_pointer + RCU_INIT_POINTER (..., NULL) Signed-off-by: Andreea-Cristina Bernat --- drivers/block/nvme-core.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/block/nvme-core.c b/drivers/block/nvme-core.c index 02351e2..cb25bdd 100644 --- a/drivers/block/nvme-core.c +++ b/drivers/block/nvme-core.c @@ -1209,7 +1209,7 @@ static void nvme_free_queues(struct nvme_dev *dev, int lowest) for (i = dev->queue_count - 1; i >= lowest; i--) { struct nvme_queue *nvmeq = raw_nvmeq(dev, i); - rcu_assign_pointer(dev->queues[i], NULL); + RCU_INIT_POINTER(dev->queues[i], NULL); call_rcu(&nvmeq->r_head, nvme_free_queue); dev->queue_count--; } -- 1.9.1