Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753398Ab3JJBkj (ORCPT ); Wed, 9 Oct 2013 21:40:39 -0400 Received: from cdptpa-omtalb.mail.rr.com ([75.180.132.120]:62341 "EHLO cdptpa-omtalb.mail.rr.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751318Ab3JJBkf (ORCPT ); Wed, 9 Oct 2013 21:40:35 -0400 X-Authority-Analysis: v=2.0 cv=LcC+G0ji c=1 sm=0 a=3SewDSjaRW4vdJyuxQ33ZQ==:17 a=DeBnktw0k-IA:10 a=3KVzincvWKMA:10 a=-1Z8MX3fR3UA:10 a=S1A5HrydsesA:10 a=8nJEP1OIZ-IA:10 a=fxJcL_dCAAAA:8 a=KGjhK52YXX0A:10 a=hNjFYzDc1A4A:10 a=QfKxxUxMAAAA:8 a=VvfF3PyllCytlaTnjZcA:9 a=wPNLvfGTeEIA:10 a=3SewDSjaRW4vdJyuxQ33ZQ==:117 X-Cloudmark-Score: 0 X-Authenticated-User: X-Originating-IP: 72.238.73.171 Message-ID: <5256058F.3010802@ubuntu.com> Date: Wed, 09 Oct 2013 21:40:31 -0400 From: Phillip Susi User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.0 MIME-Version: 1.0 To: Aaron Lu , Alan Stern , Jens Axboe , "Rafael J. Wysocki" , James Bottomley , Tejun Heo CC: linux-pm@vger.kernel.org, linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org, linux-ide@vger.kernel.org, Aaron Lu , Shane Huang , Oliver Neukum Subject: Re: block layer runtime pm and udisks References: <1364010148-8584-1-git-send-email-aaron.lu@intel.com> In-Reply-To: <1364010148-8584-1-git-send-email-aaron.lu@intel.com> X-Enigmail-Version: 1.5.2 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1737 Lines: 39 -----BEGIN PGP SIGNED MESSAGE----- Hash: SHA512 I have been trying out the new block layer runtime pm, and run into a problem: udisks keeps waking up the disk. Every 10 minutes it tries to poll the SMART status of the drive, but it does first issue an ata CHECK POWER command to see if it is in standby, and skips the check to avoid waking the disk. The problem with runtime pm is that *any* request brings the drive out of suspend, and the suspend wake path forces the drive to spin up by issuing a verify command on sector 0. Is there a reason that the wakeup path forces the drive to spin up, or could this be removed and rely on the drive waking up automatically if the request requires it? Or would it be possible to notice that the command being sent is a check power command, and fake the reply instead of resuming the device? Or does udisks just need to check the runtime pm status before trying the check power command? -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.14 (GNU/Linux) Comment: Using GnuPG with Thunderbird - http://www.enigmail.net/ iQEcBAEBCgAGBQJSVgWPAAoJEJrBOlT6nu75k/cH+gMAb9YtMS21rEt94umJpBYj BcNoyGoK39tAKZHW7pXfP2hRIm1+kPTPi44Wp7kQHu7m6BSp4YetmDkqjNv+6yAy 8SUvPcqRsJVbF1oBXN09phBEnk/JfxqID7n6hB1lT6NqYV72VVVUEUOlnSnpHtDJ gszV+TLH37uhd5/KiDFja3J2bJC0R/klzDF1x1clc53tGJd1NZ+h9tZZBLszIdnS EnjukLA02Q7ooq+445WyWth2cypTXKfRbigZW+FfCI3hfAKOShVevodlGmmrQb7Z 0xzhSoO5JTpNqJPLaNL3+JZFdXwANd+7PuO9v2XVKKUkydQ9+Vl4CfydSFhqo5U= =iuSZ -----END PGP SIGNATURE----- -- 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/