From mboxrd@z Thu Jan 1 00:00:00 1970 From: Lin Ming Subject: [RFC PATCH v3 0/4]: block layer runtime pm Date: Tue, 22 May 2012 15:21:28 +0800 Message-ID: <1337671292-15583-1-git-send-email-ming.m.lin@intel.com> Return-path: Received: from mga14.intel.com ([143.182.124.37]:16258 "EHLO mga14.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750896Ab2EVHVo (ORCPT ); Tue, 22 May 2012 03:21:44 -0400 Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: Jens Axboe , Alan Stern Cc: linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org, linux-scsi@vger.kernel.org Hi, In August 2010, Jens and Alan discussed about "Runtime PM and the block layer". http://marc.info/?t=128259108400001&r=1&w=2 Here are the RFC v3 patches that try to implement the ideas discussed. Welcome to give it a try. git pull git://git.kernel.org/pub/scm/linux/kernel/git/mlin/linux.git block_pm The test steps, for example # ls -l /sys/block/sda /sys/devices/pci0000:00/0000:00:1f.2/ata1/host0/target0:0:0/0:0:0:0/block/sda # echo auto > /sys/devices/pci0000:00/0000:00:1f.2/ata1/power/control # echo auto > /sys/devices/pci0000:00/0000:00:1f.2/ata1/host0/target0:0:0/0:0:0:0/power/control # echo 10000 > /sys/devices/pci0000:00/0000:00:1f.2/ata1/host0/target0:0:0/0:0:0:0/power/autosuspend_delay_ms Then you'll see sda is suspended after 10secs idle. # cat /sys/devices/pci0000:00/0000:00:1f.2/ata1/host0/target0:0:0/0:0:0:0/power/runtime_status suspended And if you do some IO, it will resume immediately. v3: - remove block layer suspend/resume callbacks - add block layer runtime pm helper functions v2: - remove queue idle timer, use runtime pm core's auto suspend Lin Ming (4): block: add a flag to identify PM request block: add runtime pm helpers block: implement runtime pm strategy [SCSI] sd: change to auto suspend mode block/blk-core.c | 71 ++++++++++++++++++++++++++++++++++++++++++++ block/elevator.c | 9 +++++ drivers/scsi/scsi_lib.c | 25 +++++++++++++-- drivers/scsi/scsi_pm.c | 27 ++++++++++++---- drivers/scsi/scsi_sysfs.c | 2 + drivers/scsi/sd.c | 19 ++++-------- include/linux/blk_types.h | 2 + include/linux/blkdev.h | 13 ++++++++ include/scsi/scsi_device.h | 4 ++ 9 files changed, 149 insertions(+), 23 deletions(-)