Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S966142Ab2EORkT (ORCPT ); Tue, 15 May 2012 13:40:19 -0400 Received: from ogre.sisk.pl ([193.178.161.156]:46167 "EHLO ogre.sisk.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S966101Ab2EORkR (ORCPT ); Tue, 15 May 2012 13:40:17 -0400 From: "Rafael J. Wysocki" To: Bojan Smojver Subject: Re: [PATCH v2]: In kernel hibernation, suspend to both Date: Tue, 15 May 2012 19:45:12 +0200 User-Agent: KMail/1.13.6 (Linux/3.4.0-rc7+; KDE/4.6.0; x86_64; ; ) Cc: Linux PM list , linux-kernel@vger.kernel.org References: <1337045015.1635.3.camel@shrek.rexursive.com> In-Reply-To: <1337045015.1635.3.camel@shrek.rexursive.com> MIME-Version: 1.0 Content-Type: Text/Plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <201205151945.12560.rjw@sisk.pl> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 6457 Lines: 201 On Tuesday, May 15, 2012, Bojan Smojver wrote: > Hi Rafael, > > Here is a new version of the patch, this time with comments by Srivatsa > and Alan taken on board and applied to the patch (thank you guys!). I > have tested this on my ThinkPad T510 and it worked. > > ------------------------------ > Enable suspend to both for in-kernel hibernation. > > It is often useful to suspend to memory after hibernation image has been > written to disk. If the battery runs out or power is otherwise lost, the > computer will resume from the hibernated image. If not, it will resume > from memory and hibernation image will be discarded. > > Signed-off-by: Bojan Smojver > --- > Documentation/power/swsusp.txt | 5 +++++ > kernel/power/hibernate.c | 43 ++++++++++++++++++++++++++++++++++++++++ > kernel/power/power.h | 3 +++ > kernel/power/swap.c | 28 ++++++++++++++++++++++++++ > 4 files changed, 79 insertions(+) > > diff --git a/Documentation/power/swsusp.txt b/Documentation/power/swsusp.txt > index ac190cf..92341b8 100644 > --- a/Documentation/power/swsusp.txt > +++ b/Documentation/power/swsusp.txt > @@ -33,6 +33,11 @@ echo shutdown > /sys/power/disk; echo disk > /sys/power/state > > echo platform > /sys/power/disk; echo disk > /sys/power/state > > +. If you would like to write hibernation image to swap and then suspend > +to RAM (provided your platform supports it), you can try > + > +echo suspend > /sys/power/disk; echo disk > /sys/power/state > + > . If you have SATA disks, you'll need recent kernels with SATA suspend > support. For suspend and resume to work, make sure your disk drivers > are built into kernel -- not modules. [There's way to make > diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c > index e09dfbf..a479fbd 100644 > --- a/kernel/power/hibernate.c > +++ b/kernel/power/hibernate.c > @@ -5,6 +5,7 @@ > * Copyright (c) 2003 Open Source Development Lab > * Copyright (c) 2004 Pavel Machek > * Copyright (c) 2009 Rafael J. Wysocki, Novell Inc. > + * Copyright (C) 2012 Bojan Smojver > * > * This file is released under the GPLv2. > */ > @@ -44,6 +45,9 @@ enum { > HIBERNATION_PLATFORM, > HIBERNATION_SHUTDOWN, > HIBERNATION_REBOOT, > +#ifdef CONFIG_SUSPEND > + HIBERNATION_SUSPEND, > +#endif > /* keep last */ > __HIBERNATION_AFTER_LAST > }; > @@ -572,6 +576,10 @@ int hibernation_platform_enter(void) > */ > static void power_down(void) > { > +#ifdef CONFIG_SUSPEND > + int error; > +#endif > + > switch (hibernation_mode) { > case HIBERNATION_REBOOT: > kernel_restart(NULL); > @@ -581,6 +589,32 @@ static void power_down(void) > case HIBERNATION_SHUTDOWN: > kernel_power_off(); > break; > +#ifdef CONFIG_SUSPEND > + case HIBERNATION_SUSPEND: > + error = pm_notifier_call_chain(PM_SUSPEND_PREPARE); I wouldn't do that, really. Some notifiers may assume user space to be available and in that case that might just block. > + if (!error) { > + pr_debug("PM: Entering mem sleep.\n"); > + error = suspend_devices_and_enter(PM_SUSPEND_MEM); > + } > + pm_notifier_call_chain(PM_POST_SUSPEND); > + > + if (error) { > + pr_debug("PM: Mem sleep failed. Powering down.\n"); > + if (hibernation_ops) > + hibernation_mode = HIBERNATION_PLATFORM; > + else > + hibernation_mode = HIBERNATION_SHUTDOWN; > + power_down(); > + } > + /* > + * Restore swap signature. > + */ > + error = swsusp_unmark(); > + if (error) > + printk(KERN_ERR "PM: Swap will be unusable! " > + "Try swapon -a.\n"); > + return; > +#endif > } > kernel_halt(); > /* > @@ -814,6 +848,9 @@ static const char * const hibernation_modes[] = { > [HIBERNATION_PLATFORM] = "platform", > [HIBERNATION_SHUTDOWN] = "shutdown", > [HIBERNATION_REBOOT] = "reboot", > +#ifdef CONFIG_SUSPEND > + [HIBERNATION_SUSPEND] = "suspend", > +#endif > }; > > /* > @@ -854,6 +891,9 @@ static ssize_t disk_show(struct kobject *kobj, struct kobj_attribute *attr, > switch (i) { > case HIBERNATION_SHUTDOWN: > case HIBERNATION_REBOOT: > +#ifdef CONFIG_SUSPEND > + case HIBERNATION_SUSPEND: > +#endif > break; > case HIBERNATION_PLATFORM: > if (hibernation_ops) > @@ -894,6 +934,9 @@ static ssize_t disk_store(struct kobject *kobj, struct kobj_attribute *attr, > switch (mode) { > case HIBERNATION_SHUTDOWN: > case HIBERNATION_REBOOT: > +#ifdef CONFIG_SUSPEND > + case HIBERNATION_SUSPEND: > +#endif > hibernation_mode = mode; > break; > case HIBERNATION_PLATFORM: > diff --git a/kernel/power/power.h b/kernel/power/power.h > index 98f3622..07b4a68 100644 > --- a/kernel/power/power.h > +++ b/kernel/power/power.h > @@ -156,6 +156,9 @@ extern void swsusp_free(void); > extern int swsusp_read(unsigned int *flags_p); > extern int swsusp_write(unsigned int flags); > extern void swsusp_close(fmode_t); > +#ifdef CONFIG_SUSPEND > +extern int swsusp_unmark(void); > +#endif > > /* kernel/power/block_io.c */ > extern struct block_device *hib_resume_bdev; > diff --git a/kernel/power/swap.c b/kernel/power/swap.c > index eef311a..1027da8 100644 > --- a/kernel/power/swap.c > +++ b/kernel/power/swap.c > @@ -1456,6 +1456,34 @@ void swsusp_close(fmode_t mode) > blkdev_put(hib_resume_bdev, mode); > } > > +/** > + * swsusp_unmark - Unmark swsusp signature in the resume device > + */ > + > +#ifdef CONFIG_SUSPEND > +int swsusp_unmark(void) > +{ > + int error; > + > + hib_bio_read_page(swsusp_resume_block, swsusp_header, NULL); > + if (!memcmp(HIBERNATE_SIG,swsusp_header->sig, 10)) { > + memcpy(swsusp_header->sig,swsusp_header->orig_sig, 10); > + error = hib_bio_write_page(swsusp_resume_block, > + swsusp_header, NULL); > + } else { > + printk(KERN_ERR "PM: Cannot find swsusp signature!\n"); > + error = -ENODEV; > + } > + > + /* > + * We just returned from suspend, we don't need the image any more. > + */ > + free_all_swap_pages(root_swap); > + > + return error; > +} > +#endif > + > static int swsusp_header_init(void) > { > swsusp_header = (struct swsusp_header*) __get_free_page(GFP_KERNEL); > ------------------------------ Thanks, Rafael -- 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/