From f6eafe3665bcc374c66775d58312d1c06c55303f Mon Sep 17 00:00:00 2001
From: Ian Campbell <Ian.Campbell@citrix.com>
Date: Wed, 25 Nov 2009 14:12:08 +0000
Subject: [PATCH] xen: call clock resume notifier on all CPUs

tick_resume() is never called on secondary processors. Presumably this
is because they are offlined for suspend on native and so this is
normally taken care of in the CPU onlining path. Under Xen we keep all
CPUs online over a suspend.

This patch papers over the issue for me but I will investigate a more
generic, less hacky, way of doing to the same.

tick_suspend is also only called on the boot CPU which I presume should
be fixed too.

Signed-off-by: Ian Campbell <Ian.Campbell@citrix.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Stable Kernel <stable@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
---
 arch/x86/xen/suspend.c | 15 ++++++++++++++-
 1 file changed, 14 insertions(+), 1 deletion(-)

diff --git a/arch/x86/xen/suspend.c b/arch/x86/xen/suspend.c
index 6343a5d8e93c..987267f79bf5 100644
--- a/arch/x86/xen/suspend.c
+++ b/arch/x86/xen/suspend.c
@@ -1,4 +1,5 @@
 #include <linux/types.h>
+#include <linux/clockchips.h>
 
 #include <xen/interface/xen.h>
 #include <xen/grant_table.h>
@@ -46,7 +47,19 @@ void xen_post_suspend(int suspend_cancelled)
 
 }
 
+static void xen_vcpu_notify_restore(void *data)
+{
+	unsigned long reason = (unsigned long)data;
+
+	/* Boot processor notified via generic timekeeping_resume() */
+	if ( smp_processor_id() == 0)
+		return;
+
+	clockevents_notify(reason, NULL);
+}
+
 void xen_arch_resume(void)
 {
-	/* nothing */
+	smp_call_function(xen_vcpu_notify_restore,
+			       (void *)CLOCK_EVT_NOTIFY_RESUME, 1);
 }