From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S263419AbUE1PKc (ORCPT ); Fri, 28 May 2004 11:10:32 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S263435AbUE1PKc (ORCPT ); Fri, 28 May 2004 11:10:32 -0400 Received: from jurassic.park.msu.ru ([195.208.223.243]:12929 "EHLO jurassic.park.msu.ru") by vger.kernel.org with ESMTP id S263419AbUE1PKa (ORCPT ); Fri, 28 May 2004 11:10:30 -0400 Date: Fri, 28 May 2004 19:10:28 +0400 From: Ivan Kokshaysky To: Bartlomiej Zolnierkiewicz Cc: Andrew Morton , linux-kernel@vger.kernel.org Subject: Re: [patch 2.6] don't put IDE disks in standby mode on halt on Alpha Message-ID: <20040528191028.A1117@jurassic.park.msu.ru> References: <20040527194920.A1709@jurassic.park.msu.ru> <200405271854.21499.bzolnier@elka.pw.edu.pl> <20040527210821.A2004@jurassic.park.msu.ru> <200405271940.49386.bzolnier@elka.pw.edu.pl> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.2.5i In-Reply-To: <200405271940.49386.bzolnier@elka.pw.edu.pl>; from B.Zolnierkiewicz@elka.pw.edu.pl on Thu, May 27, 2004 at 07:40:49PM +0200 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Thu, May 27, 2004 at 07:40:49PM +0200, Bartlomiej Zolnierkiewicz wrote: > > Would #ifdef __alpha__ be better? > > actually CONFIG_ALPHA + comment why it is needed Ok, but now I'm thinking of probably better solution: consider sys_state == SYSTEM_HALT as another special case where we put the disk into standby mode *only* if it does have write cache but doesn't suppurt cache flush command (or cache flush fails for some reason). Hopefully, most drives won't be spun down on halt. I think that it should be acceptable for x86 as well. Ivan. --- 2.6/drivers/ide/ide-disk.c Fri May 28 17:46:35 2004 +++ linux/drivers/ide/ide-disk.c Fri May 28 18:42:47 2004 @@ -1686,13 +1686,19 @@ static void idedisk_setup (ide_drive_t * #endif } -static void ide_cacheflush_p(ide_drive_t *drive) +static int ide_cacheflush_p(ide_drive_t *drive) { - if (!drive->wcache || !ide_id_has_flush_cache(drive->id)) - return; + if (!drive->wcache) + return 0; + + if (!ide_id_has_flush_cache(drive->id)) + return 1; - if (do_idedisk_flushcache(drive)) - printk(KERN_INFO "%s: wcache flush failed!\n", drive->name); + if (!do_idedisk_flushcache(drive)) + return 0; + + printk(KERN_INFO "%s: wcache flush failed!\n", drive->name); + return 1; } static int idedisk_cleanup (ide_drive_t *drive) @@ -1713,10 +1719,16 @@ static void ide_device_shutdown(struct d { ide_drive_t *drive = container_of(dev, ide_drive_t, gendev); + /* Never spin the disk down on reboot. */ if (system_state == SYSTEM_RESTART) { ide_cacheflush_p(drive); return; } + + /* Spin the disk down on halt only if attempt to flush the + write cache fails. */ + if (system_state == SYSTEM_HALT && !ide_cacheflush_p(drive)) + return; printk("Shutdown: %s\n", drive->name); dev->bus->suspend(dev, PM_SUSPEND_STANDBY);