PM: Rework handling of interrupts during suspend-resume

Use the functions introduced in by the previous patch,
suspend_device_irqs(), resume_device_irqs() and check_wakeup_irqs(),
to rework the handling of interrupts during suspend (hibernation) and
resume.  Namely, interrupts will only be disabled on the CPU right
before suspending sysdevs, while device drivers will be prevented
from receiving interrupts, with the help of the new helper function,
before their "late" suspend callbacks run (and analogously during
resume).

In addition, since the device interrups are now disabled before the
CPU has turned all interrupts off and the CPU will ACK the interrupts
setting the IRQ_PENDING bit for them, check in sysdev_suspend() if
any wake-up interrupts are pending and abort suspend if that's the
case.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 9 insertions, 7 deletions

diff --git a/drivers/xen/manage.c b/drivers/xen/manage.c
index 3ccd348d112d..0d61db1e7b49 100644
--- a/drivers/xen/manage.c
+++ b/drivers/xen/manage.c
@@ -39,12 +39,6 @@ static int xen_suspend(void *data)
 
         BUG_ON(!irqs_disabled());
 
-        err = device_power_down(PMSG_SUSPEND);
-        if (err) {
-                printk(KERN_ERR "xen_suspend: device_power_down failed: %d\n",
-                       err);
-                return err;
-        }
         err = sysdev_suspend(PMSG_SUSPEND);
         if (err) {
                 printk(KERN_ERR "xen_suspend: sysdev_suspend failed: %d\n",
@@ -69,7 +63,6 @@ static int xen_suspend(void *data)
         xen_mm_unpin_all();
 
         sysdev_resume();
-        device_power_up(PMSG_RESUME);
 
         if (!*cancelled) {
                 xen_irq_resume();
@@ -108,6 +101,12 @@ static void do_suspend(void)
         /* XXX use normal device tree? */
         xenbus_suspend();
 
+        err = device_power_down(PMSG_SUSPEND);
+        if (err) {
+                printk(KERN_ERR "device_power_down failed: %d\n", err);
+                goto resume_devices;
+        }
+
         err = stop_machine(xen_suspend, &cancelled, cpumask_of(0));
         if (err) {
                 printk(KERN_ERR "failed to start xen_suspend: %d\n", err);
@@ -120,6 +119,9 @@ static void do_suspend(void)
         } else
                 xenbus_suspend_cancel();
 
+        device_power_up(PMSG_RESUME);
+
+resume_devices:
         device_resume(PMSG_RESUME);
 
         /* Make sure timer events get retriggered on all CPUs */