From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755400AbcIMIDP (ORCPT ); Tue, 13 Sep 2016 04:03:15 -0400 Received: from mail-ua0-f193.google.com ([209.85.217.193]:34095 "EHLO mail-ua0-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751574AbcIMIDN (ORCPT ); Tue, 13 Sep 2016 04:03:13 -0400 MIME-Version: 1.0 In-Reply-To: References: <566ABCD9.1060404@users.sourceforge.net> <57806eb1-10ed-582e-72d0-2975e1ee967a@users.sourceforge.net> From: Ilya Dryomov Date: Tue, 13 Sep 2016 10:03:11 +0200 Message-ID: Subject: Re: [PATCH 04/47] block-rbd: Refactor two calls for memory allocations in rbd_dev_image_id() To: SF Markus Elfring Cc: Ceph Development , Alex Elder , Sage Weil , LKML , kernel-janitors@vger.kernel.org, Julia Lawall Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Sep 12, 2016 at 8:45 PM, SF Markus Elfring wrote: > From: Markus Elfring > Date: Sun, 11 Sep 2016 14:48:41 +0200 > > * Pass the sizes for memory allocations to the corresponding functions > directly without storing the calculated values in an > intermediate variable. > > * Delete the local variable "size" which became unnecessary with > this refactoring. > > Signed-off-by: Markus Elfring > --- > drivers/block/rbd.c | 10 ++++------ > 1 file changed, 4 insertions(+), 6 deletions(-) > > diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c > index d61a066..c1da844 100644 > --- a/drivers/block/rbd.c > +++ b/drivers/block/rbd.c > @@ -5833,7 +5833,6 @@ again: > static int rbd_dev_image_id(struct rbd_device *rbd_dev) > { > int ret; > - size_t size; > char *object_name; > void *response; > char *image_id; > @@ -5854,17 +5853,16 @@ static int rbd_dev_image_id(struct rbd_device *rbd_dev) > * First, see if the format 2 image id file exists, and if > * so, get the image's persistent id from it. > */ > - size = sizeof (RBD_ID_PREFIX) + strlen(rbd_dev->spec->image_name); > - object_name = kmalloc(size, GFP_NOIO); > + object_name = kmalloc(sizeof(RBD_ID_PREFIX) > + + strlen(rbd_dev->spec->image_name), > + GFP_NOIO); > if (!object_name) > return -ENOMEM; > sprintf(object_name, "%s%s", RBD_ID_PREFIX, rbd_dev->spec->image_name); > dout("rbd id object name is %s\n", object_name); > > /* Response will be an encoded string, which includes a length */ > - > - size = sizeof (__le32) + RBD_IMAGE_ID_LEN_MAX; > - response = kzalloc(size, GFP_NOIO); > + response = kzalloc(sizeof(__le32) + RBD_IMAGE_ID_LEN_MAX, GFP_NOIO); > if (!response) { > ret = -ENOMEM; > goto out; > -- > 2.10.0 > How is this any better? If anything, it makes the first kmalloc() call slightly less readable. Thanks, Ilya