tick/xen: Provide and use tick_suspend_local() and tick_resume_local()
Xen calls on every cpu into tick_resume() which is just wrong.
tick_resume() is for the syscore global suspend/resume
invocation. What XEN really wants is a per cpu local resume
function.
Provide a tick_resume_local() function and use it in XEN.
Also provide a complementary tick_suspend_local() and modify
tick_unfreeze() and tick_freeze(), respectively, to use the
new local tick resume/suspend functions.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
[ Combined two patches, rebased, modified subject/changelog. ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: David Vrabel <david.vrabel@citrix.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1698741.eezk9tnXtG@vostro.rjw.lan
[ Merged to latest timers/core. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
diff --git a/kernel/time/tick-common.c b/kernel/time/tick-common.c
index 1a60c2a..da796d6 100644
--- a/kernel/time/tick-common.c
+++ b/kernel/time/tick-common.c
@@ -374,6 +374,41 @@
}
/**
+ * tick_suspend_local - Suspend the local tick device
+ *
+ * Called from the local cpu for freeze with interrupts disabled.
+ *
+ * No locks required. Nothing can change the per cpu device.
+ */
+static void tick_suspend_local(void)
+{
+ struct tick_device *td = this_cpu_ptr(&tick_cpu_device);
+
+ clockevents_shutdown(td->evtdev);
+}
+
+/**
+ * tick_resume_local - Resume the local tick device
+ *
+ * Called from the local CPU for unfreeze or XEN resume magic.
+ *
+ * No locks required. Nothing can change the per cpu device.
+ */
+void tick_resume_local(void)
+{
+ struct tick_device *td = this_cpu_ptr(&tick_cpu_device);
+ bool broadcast = tick_resume_check_broadcast();
+
+ clockevents_tick_resume(td->evtdev);
+ if (!broadcast) {
+ if (td->mode == TICKDEV_MODE_PERIODIC)
+ tick_setup_periodic(td->evtdev, 0);
+ else
+ tick_resume_oneshot();
+ }
+}
+
+/**
* tick_suspend - Suspend the tick and the broadcast device
*
* Called from syscore_suspend() via timekeeping_suspend with only one
@@ -384,9 +419,7 @@
*/
void tick_suspend(void)
{
- struct tick_device *td = this_cpu_ptr(&tick_cpu_device);
-
- clockevents_shutdown(td->evtdev);
+ tick_suspend_local();
tick_suspend_broadcast();
}
@@ -394,26 +427,14 @@
* tick_resume - Resume the tick and the broadcast device
*
* Called from syscore_resume() via timekeeping_resume with only one
- * CPU online and interrupts disabled or from tick_unfreeze() under
- * tick_freeze_lock.
+ * CPU online and interrupts disabled.
*
* No locks required. Nothing can change the per cpu device.
*/
void tick_resume(void)
{
- struct tick_device *td;
- int broadcast;
-
- broadcast = tick_resume_broadcast();
- td = this_cpu_ptr(&tick_cpu_device);
- clockevents_tick_resume(td->evtdev);
-
- if (!broadcast) {
- if (td->mode == TICKDEV_MODE_PERIODIC)
- tick_setup_periodic(td->evtdev, 0);
- else
- tick_resume_oneshot();
- }
+ tick_resume_broadcast();
+ tick_resume_local();
}
static DEFINE_RAW_SPINLOCK(tick_freeze_lock);
@@ -436,7 +457,7 @@
if (tick_freeze_depth == num_online_cpus()) {
timekeeping_suspend();
} else {
- tick_suspend();
+ tick_suspend_local();
}
raw_spin_unlock(&tick_freeze_lock);