Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752564AbbKKVRv (ORCPT ); Wed, 11 Nov 2015 16:17:51 -0500 Received: from mail-io0-f175.google.com ([209.85.223.175]:33489 "EHLO mail-io0-f175.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752046AbbKKVRt (ORCPT ); Wed, 11 Nov 2015 16:17:49 -0500 Subject: Re: [PATCH] mmc: change to use kmalloc To: Alim Akhtar , yalin wang References: <1447215791-19429-1-git-send-email-yalin.wang2010@gmail.com> Cc: Ulf Hansson , Adrian Hunter , ben@decadent.org.uk, Jaehoon Chung , asaf.vertz@tandemg.com, tklauser@distanz.ch, jonathanh@nvidia.com, "James E.J. Bottomley" , Grant Grundler , "linux-mmc@vger.kernel.org" , "linux-kernel@vger.kernel.org" From: Peter Hurley Message-ID: <5643B07A.3090208@hurleysoftware.com> Date: Wed, 11 Nov 2015 16:17:46 -0500 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.3.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1400 Lines: 40 On 11/11/2015 12:02 PM, Alim Akhtar wrote: > Hi Yalin, > > On Wed, Nov 11, 2015 at 9:53 AM, yalin wang wrote: >> Use kmalloc instead of kzalloc, zero the memory is not needed. >> > why you want to do this? what problem you faces, and how this resolves the same? The patch fixes an inefficiency: explicitly zeroing memory that is then immediately overwritten 6 lines below is wasteful. Regards, Peter Hurley >> Signed-off-by: yalin wang >> --- >> drivers/mmc/card/block.c | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/drivers/mmc/card/block.c b/drivers/mmc/card/block.c >> index 23b6c8e..975cd3e 100644 >> --- a/drivers/mmc/card/block.c >> +++ b/drivers/mmc/card/block.c >> @@ -365,7 +365,7 @@ static struct mmc_blk_ioc_data *mmc_blk_ioctl_copy_from_user( >> if (!idata->buf_bytes) >> return idata; >> >> - idata->buf = kzalloc(idata->buf_bytes, GFP_KERNEL); >> + idata->buf = kmalloc(idata->buf_bytes, GFP_KERNEL); >> if (!idata->buf) { >> err = -ENOMEM; >> goto idata_err; >> -- >> 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/