From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ulf Hansson Subject: Re: [PATCH V2 2/2] mmc: Minimize resume-time by deferring resume Date: Wed, 14 Dec 2011 16:29:04 +0100 Message-ID: <4EE8C0C0.6010307@stericsson.com> References: <1323875170-7103-1-git-send-email-ulf.hansson@stericsson.com> <1323875170-7103-3-git-send-email-ulf.hansson@stericsson.com> Mime-Version: 1.0 Content-Type: text/plain; charset="ISO-8859-1"; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from eu1sys200aog107.obsmtp.com ([207.126.144.123]:38429 "EHLO eu1sys200aog107.obsmtp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753859Ab1LNP3T (ORCPT ); Wed, 14 Dec 2011 10:29:19 -0500 In-Reply-To: Sender: linux-mmc-owner@vger.kernel.org List-Id: linux-mmc@vger.kernel.org To: Vitaly Wool Cc: "linux-mmc@vger.kernel.org" , Chris Ball , Per FORLIN , Johan RUDHOLM , Lee Jones Vitaly Wool wrote: > Hi Ulf, > > On Wed, Dec 14, 2011 at 4:06 PM, Ulf Hansson > wrote: > Typically an sd/mmc card takes around 200 - 1100 ms to > initialize when the power to the card has been cut, which > is what happens during a suspend/resume sequence. > > I'm a bit pessimistic about this patch. What if we have a root filesystem on an SD card, or, what is a more common case, on an eMMC? How is it going to be handled? > This is handled for sure. I have verified this case and I agree that this is likely a common case. In principle, every mmc/sd requests handled in issue_rq (block.c), will unless the host is not already resumed, do a "sync" of the resume work. > I see no trace of taking this into account in here so it's a NAK for now from my side. > > Thanks, > Vitaly > Br Ulf Hansson