From patchwork Sun Nov 23 10:48:56 2008 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Julia Lawall X-Patchwork-Id: 10301 X-Patchwork-Delegate: paulus@samba.org Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from ozlabs.org (localhost [127.0.0.1]) by ozlabs.org (Postfix) with ESMTP id 7EF60DE032 for ; Sun, 23 Nov 2008 22:16:17 +1100 (EST) X-Original-To: linuxppc-dev@ozlabs.org Delivered-To: linuxppc-dev@ozlabs.org X-Greylist: delayed 1610 seconds by postgrey-1.31 at ozlabs; Sun, 23 Nov 2008 22:15:57 EST Received: from mgw1.diku.dk (mgw1.diku.dk [130.225.96.91]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client CN "mgw1.diku.dk", Issuer "KU Security Authority" (not verified)) by ozlabs.org (Postfix) with ESMTPS id 91904DDDE7 for ; Sun, 23 Nov 2008 22:15:57 +1100 (EST) Received: from localhost (localhost [127.0.0.1]) by mgw1.diku.dk (Postfix) with ESMTP id 6D11A52C379; Sun, 23 Nov 2008 11:48:58 +0100 (CET) X-Virus-Scanned: amavisd-new at diku.dk Received: from mgw1.diku.dk ([127.0.0.1]) by localhost (mgw1.diku.dk [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id EnG2m2sJmi6J; Sun, 23 Nov 2008 11:48:57 +0100 (CET) Received: from nhugin.diku.dk (nhugin.diku.dk [130.225.96.140]) by mgw1.diku.dk (Postfix) with ESMTP id 197AD52C35C; Sun, 23 Nov 2008 11:48:57 +0100 (CET) Received: from ask.diku.dk (ask.diku.dk [130.225.96.225]) by nhugin.diku.dk (Postfix) with ESMTP id 8F8286DF8B9; Sun, 23 Nov 2008 11:46:53 +0100 (CET) Received: by ask.diku.dk (Postfix, from userid 3767) id D345127257E; Sun, 23 Nov 2008 11:48:56 +0100 (CET) Received: from localhost (localhost [127.0.0.1]) by ask.diku.dk (Postfix) with ESMTP id 9DB7927257A; Sun, 23 Nov 2008 11:48:56 +0100 (CET) Date: Sun, 23 Nov 2008 11:48:56 +0100 (CET) From: Julia Lawall To: paulus@samba.org, benh@kernel.crashing.org, linuxppc-dev@ozlabs.org, linux-kernel@vger.kernel.org, kernel-janitors@vger.kernel.org Subject: [PATCH 4/5] arch/powerpc: Eliminate NULL test and memset after alloc_bootmem Message-ID: MIME-Version: 1.0 X-BeenThere: linuxppc-dev@ozlabs.org X-Mailman-Version: 2.1.11 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: linuxppc-dev-bounces+patchwork-incoming=ozlabs.org@ozlabs.org Errors-To: linuxppc-dev-bounces+patchwork-incoming=ozlabs.org@ozlabs.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/powerpc/kernel/setup_64.c | 2 -- 1 files changed, 0 insertions(+), 2 deletions(-) diff --git a/arch/powerpc/kernel/setup_64.c b/arch/powerpc/kernel/setup_64.c index 9dca8cf..261c1b0 100644 --- a/arch/powerpc/kernel/setup_64.c +++ b/arch/powerpc/kernel/setup_64.c @@ -606,8 +606,6 @@ void __init setup_per_cpu_areas(void) for_each_possible_cpu(i) { ptr = alloc_bootmem_pages_node(NODE_DATA(cpu_to_node(i)), size); - if (!ptr) - panic("Cannot allocate cpu data for CPU %d\n", i); paca[i].data_offset = ptr - __per_cpu_start; memcpy(ptr, __per_cpu_start, __per_cpu_end - __per_cpu_start);