Commit b3e96c0c authored by Shriram Rajagopalan's avatar Shriram Rajagopalan Committed by Konrad Rzeszutek Wilk
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xen: use freeze/restore/thaw PM events for suspend/resume/chkpt 



Use PM_FREEZE, PM_THAW and PM_RESTORE power events for
suspend/resume/checkpoint functionality, instead of PM_SUSPEND
and PM_RESUME. Use of these pm events fixes the Xen Guest hangup
when taking checkpoints. When a suspend event is cancelled
(while taking checkpoints once/continuously), we use PM_THAW
instead of PM_RESUME. PM_RESTORE is used when suspend is not
cancelled. See Documentation/power/devices.txt and linux/pm.h
for more info about freeze, thaw and restore. The sequence of
pm events in a suspend-resume scenario is shown below.

        dpm_suspend_start(PMSG_FREEZE);

                dpm_suspend_noirq(PMSG_FREEZE);

                       sysdev_suspend(PMSG_FREEZE);
                       cancelled = suspend_hypercall()
                       sysdev_resume();

               dpm_resume_noirq(cancelled ? PMSG_THAW : PMSG_RESTORE);

       dpm_resume_end(cancelled ? PMSG_THAW : PMSG_RESTORE);

Acked-by: default avatarIan Campbell <ian.campbell@citrix.com>
Signed-off-by: default avatarShriram Rajagopalan <rshriram@cs.ubc.ca>
Signed-off-by: default avatarKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
parent c7853aea

drivers/xen/manage.c

+8 −8
Original line number Diff line number Diff line
@@ -61,7 +61,7 @@ static void xen_post_suspend(int cancelled) 
	xen_mm_unpin_all();

}



#ifdef CONFIG_PM_SLEEP

#ifdef CONFIG_HIBERNATION

static int xen_suspend(void *data)

{

	struct suspend_info *si = data;
@@ -69,7 +69,7 @@ static int xen_suspend(void *data) 


	BUG_ON(!irqs_disabled());



	err = sysdev_suspend(PMSG_SUSPEND);

	err = sysdev_suspend(PMSG_FREEZE);

	if (err) {

		printk(KERN_ERR "xen_suspend: sysdev_suspend failed: %d\n",

			err);
@@ -118,7 +118,7 @@ static void do_suspend(void) 
	}

#endif



	err = dpm_suspend_start(PMSG_SUSPEND);

	err = dpm_suspend_start(PMSG_FREEZE);

	if (err) {

		printk(KERN_ERR "xen suspend: dpm_suspend_start %d\n", err);

		goto out_thaw;
@@ -127,7 +127,7 @@ static void do_suspend(void) 
	printk(KERN_DEBUG "suspending xenstore...\n");

	xs_suspend();



	err = dpm_suspend_noirq(PMSG_SUSPEND);

	err = dpm_suspend_noirq(PMSG_FREEZE);

	if (err) {

		printk(KERN_ERR "dpm_suspend_noirq failed: %d\n", err);

		goto out_resume;
@@ -147,7 +147,7 @@ static void do_suspend(void) 


	err = stop_machine(xen_suspend, &si, cpumask_of(0));



	dpm_resume_noirq(PMSG_RESUME);

	dpm_resume_noirq(si.cancelled ? PMSG_THAW : PMSG_RESTORE);



	if (err) {

		printk(KERN_ERR "failed to start xen_suspend: %d\n", err);
@@ -161,7 +161,7 @@ out_resume: 
	} else

		xs_suspend_cancel();



	dpm_resume_end(PMSG_RESUME);

	dpm_resume_end(si.cancelled ? PMSG_THAW : PMSG_RESTORE);



	/* Make sure timer events get retriggered on all CPUs */

	clock_was_set();
@@ -173,7 +173,7 @@ out: 
#endif

	shutting_down = SHUTDOWN_INVALID;

}

#endif	/* CONFIG_PM_SLEEP */

#endif	/* CONFIG_HIBERNATION */



struct shutdown_handler {

	const char *command;
@@ -202,7 +202,7 @@ static void shutdown_handler(struct xenbus_watch *watch, 
		{ "poweroff",	do_poweroff },

		{ "halt",	do_poweroff },

		{ "reboot",	do_reboot   },

#ifdef CONFIG_PM_SLEEP

#ifdef CONFIG_HIBERNATION

		{ "suspend",	do_suspend  },

#endif

		{NULL, NULL},

drivers/xen/xenbus/xenbus_probe_frontend.c

+5 −3
Original line number Diff line number Diff line
@@ -88,7 +88,9 @@ static struct device_attribute xenbus_frontend_dev_attrs[] = { 
static const struct dev_pm_ops xenbus_pm_ops = {

	.suspend	= xenbus_dev_suspend,

	.resume		= xenbus_dev_resume,

	.freeze		= xenbus_dev_suspend,

	.thaw		= xenbus_dev_cancel,

	.restore	= xenbus_dev_resume,

};



static struct xen_bus_type xenbus_frontend = {

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