From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758443AbYKWKrT (ORCPT ); Sun, 23 Nov 2008 05:47:19 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756479AbYKWKrD (ORCPT ); Sun, 23 Nov 2008 05:47:03 -0500 Received: from mgw1.diku.dk ([130.225.96.91]:59965 "EHLO mgw1.diku.dk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756074AbYKWKrB (ORCPT ); Sun, 23 Nov 2008 05:47:01 -0500 Date: Sun, 23 Nov 2008 11:46:58 +0100 (CET) From: Julia Lawall To: hskinnemoen@atmel.com, linux-kernel@vger.kernel.org, kernel-janitors@vger.kernel.org Subject: [PATCH 2/5] arch/avr32: Eliminate NULL test and memset after alloc_bootmem Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Julia Lawall As noted by Akinobu Mita in patch b1fceac2b9e04d278316b2faddf276015fc06e3b, alloc_bootmem and related functions never return NULL and always return a zeroed region of memory. Thus a NULL test or memset after calls to these functions is unnecessary. This was fixed using the following semantic patch. (http://www.emn.fr/x-info/coccinelle/) // @@ expression E; statement S; @@ E = \(alloc_bootmem\|alloc_bootmem_low\|alloc_bootmem_pages\|alloc_bootmem_low_pages\|alloc_bootmem_node\|alloc_bootmem_low_pages_node\|alloc_bootmem_pages_node\)(...) ... when != E ( - BUG_ON (E == NULL); | - if (E == NULL) S ) @@ expression E,E1; @@ E = \(alloc_bootmem\|alloc_bootmem_low\|alloc_bootmem_pages\|alloc_bootmem_low_pages\|alloc_bootmem_node\|alloc_bootmem_low_pages_node\|alloc_bootmem_pages_node\)(...) ... when != E - memset(E,0,E1); // Signed-off-by: Julia Lawall --- arch/avr32/mm/init.c | 1 - 1 files changed, 0 insertions(+), 1 deletions(-) diff --git a/arch/avr32/mm/init.c b/arch/avr32/mm/init.c index fa92ff6..e819fa6 100644 --- a/arch/avr32/mm/init.c +++ b/arch/avr32/mm/init.c @@ -97,7 +97,6 @@ void __init paging_init(void) mem_map = NODE_DATA(0)->node_mem_map; - memset(zero_page, 0, PAGE_SIZE); empty_zero_page = virt_to_page(zero_page); flush_dcache_page(empty_zero_page); }