From mboxrd@z Thu Jan 1 00:00:00 1970 From: Per Forlin Subject: Re: [PATCH] mmc: mxs-mmc: add support for pre_req and post_req Date: Wed, 20 Apr 2011 10:01:22 +0200 Message-ID: References: <1302116833-24540-1-git-send-email-per.forlin@linaro.org> <1303058010-30256-1-git-send-email-shawn.guo@linaro.org> <20110417164830.GE17935@S2100-06.ap.freescale.net> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: Received: from mail-qy0-f174.google.com ([209.85.216.174]:43308 "EHLO mail-qy0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750750Ab1DTIBX convert rfc822-to-8bit (ORCPT ); Wed, 20 Apr 2011 04:01:23 -0400 Received: by qyk7 with SMTP id 7so2103648qyk.19 for ; Wed, 20 Apr 2011 01:01:23 -0700 (PDT) In-Reply-To: <20110417164830.GE17935@S2100-06.ap.freescale.net> Sender: linux-mmc-owner@vger.kernel.org List-Id: linux-mmc@vger.kernel.org To: Shawn Guo Cc: Shawn Guo , linaro-kernel@lists.linaro.org, linux-mmc@vger.kernel.org, cjb@laptop.org, linux-arm-kernel@lists.infradead.org, patches@linaro.org On 17 April 2011 18:48, Shawn Guo wrote: > On Mon, Apr 18, 2011 at 12:33:30AM +0800, Shawn Guo wrote: >> pre_req() runs dma_map_sg() post_req() runs dma_unmap_sg. >> If not calling pre_req() before mxs_mmc_request(), request() >> will prepare the cache just like it did it before. >> It is optional to use pre_req() and post_req(). >> >> Signed-off-by: Shawn Guo >> --- >> =A0drivers/mmc/host/mxs-mmc.c | =A0 75 +++++++++++++++++++++++++++++= +++++++++++++-- >> =A01 files changed, 72 insertions(+), 3 deletions(-) >> > > Here is the result of mmc_test case 37 ~ 40, which are designed to se= e > the performance improvement introduced by non-blocking changes. > > Honestly, the improvement is not so impressive. =A0Not sure if the pa= tch > for mxs-mmc pre_req and post_req support was correctly produced. =A0S= o > please help review ... My guess is that dma_unmap is not run in parallel with transfer. Please look at my patch reply. > > -- > Regards, > Shawn Regards, Per