From mboxrd@z Thu Jan 1 00:00:00 1970 From: Chris Ball Subject: Re: [PATCH RESEND v6] mmc: core: Remove bounce buffer in mmc_send_cxd_data() Date: Mon, 17 Sep 2012 03:32:12 -0400 Message-ID: References: <1343955483-6917-1-git-send-email-kyungsik.lee@lge.com> Mime-Version: 1.0 Content-Type: text/plain Return-path: In-Reply-To: <1343955483-6917-1-git-send-email-kyungsik.lee@lge.com> (Kyungsik Lee's message of "Fri, 3 Aug 2012 09:58:03 +0900") Sender: linux-kernel-owner@vger.kernel.org To: Kyungsik Lee Cc: Venkatraman S , Jaehoon Chung , Adrian Hunter , Philip Rakity , raphael.andy.lee@gmail.com, linux-mmc@vger.kernel.org, linux-kernel@vger.kernel.org List-Id: linux-mmc@vger.kernel.org Hi, On Thu, Aug 02 2012, Kyungsik Lee wrote: > It is expected that Extended CSD register(the size of this register > is larger than CID/CSD) will be referenced more frequently as more > fields have been added to Extended CSD and it seems that it is not > a good option to double the memory used. > > This patch is intended to avoid the use of bounce buffer for reading > Extended CSD register in mmc_send_cxd_data(). It will provide a better > performance gain by removing memcpy() overhead for a half KiB and > a redundant bounce buffer allocated repeatedly at the cost of providing > DMA-capable buffer from upper caller(but on-stack buffer is allowed > with no performance gain). > > Signed-off-by: Kyungsik Lee > Reviewed-by: Venkatraman S Thanks, pushed to mmc-next for 3.7. - Chris. -- Chris Ball One Laptop Per Child