From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758628AbYFXI0S (ORCPT ); Tue, 24 Jun 2008 04:26:18 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1758653AbYFXI0A (ORCPT ); Tue, 24 Jun 2008 04:26:00 -0400 Received: from mgw1.diku.dk ([130.225.96.91]:45725 "EHLO mgw1.diku.dk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757555AbYFXIZ5 (ORCPT ); Tue, 24 Jun 2008 04:25:57 -0400 Date: Tue, 24 Jun 2008 10:25:54 +0200 (CEST) From: Julia Lawall To: akinobu.mita@gmail.com, schwidefsky@de.ibm.com, heiko.carstens@de.ibm.com, linux390@de.ibm.com, linux-s390@vger.kernel.org, linux-kernel@vger.kernel.org, kernel-janitors@vger.kernel.org Subject: [PATCH 11/14] drivers/s390: 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. drivers/s390/char/raw3270.c | 11 +---------- drivers/s390/char/sclp_con.c | 2 -- 2 files changed, 1 insertion(+), 12 deletions(-) This was fixed using the following semantic patch. (http://www.emn.fr/x-info/coccinelle/) // @@ expression E; statement S; @@ E = \(alloc_bootmem\|alloc_bootmem_low\|alloc_bootmem_pages\|alloc_bootmem_low_pages\)(...) ... when != E ( - BUG_ON (E == NULL); | - if (E == NULL) S ) @@ expression E,E1; @@ E = \(alloc_bootmem\|alloc_bootmem_low\|alloc_bootmem_pages\|alloc_bootmem_low_pages\)(...) ... when != E - memset(E,0,E1); // Signed-off-by: Julia Lawall --- diff -u -p a/drivers/s390/char/raw3270.c b/drivers/s390/char/raw3270.c --- a/drivers/s390/char/raw3270.c +++ b/drivers/s390/char/raw3270.c @@ -153,19 +153,10 @@ struct raw3270_request __init *raw3270_r struct raw3270_request *rq; rq = alloc_bootmem_low(sizeof(struct raw3270)); - if (!rq) - return ERR_PTR(-ENOMEM); - memset(rq, 0, sizeof(struct raw3270_request)); /* alloc output buffer. */ - if (size > 0) { + if (size > 0) rq->buffer = alloc_bootmem_low(size); - if (!rq->buffer) { - free_bootmem((unsigned long) rq, - sizeof(struct raw3270)); - return ERR_PTR(-ENOMEM); - } - } rq->size = size; INIT_LIST_HEAD(&rq->list); diff -u -p a/drivers/s390/char/sclp_con.c b/drivers/s390/char/sclp_con.c --- a/drivers/s390/char/sclp_con.c +++ b/drivers/s390/char/sclp_con.c @@ -222,8 +222,6 @@ sclp_console_init(void) INIT_LIST_HEAD(&sclp_con_pages); for (i = 0; i < MAX_CONSOLE_PAGES; i++) { page = alloc_bootmem_low_pages(PAGE_SIZE); - if (page == NULL) - return -ENOMEM; list_add_tail((struct list_head *) page, &sclp_con_pages); } INIT_LIST_HEAD(&sclp_con_outqueue);