summary refs log tree commit diff
path: root/arch/x86/kernel/kvmclock.c
diff options
context:
space:
mode:
authorMarcelo Tosatti <mtosatti@redhat.com>2012-02-13 11:07:27 -0200
committerAvi Kivity <avi@redhat.com>2012-03-20 12:37:45 +0200
commitb74f05d61b73af584d0c39121980171389ecfaaa (patch)
tree1406185fb45430549b37ef3b4f62f9c5772ef139 /arch/x86/kernel/kvmclock.c
parent9587190107d0c0cbaccbf7bf6b0245d29095a9ae (diff)
downloadlinux-b74f05d61b73af584d0c39121980171389ecfaaa.tar.gz
x86: kvmclock: abstract save/restore sched_clock_state
Upon resume from hibernation, CPU 0's hvclock area contains the old
values for system_time and tsc_timestamp. It is necessary for the
hypervisor to update these values with uptodate ones before the CPU uses
them.

Abstract TSC's save/restore sched_clock_state functions and use
restore_state to write to KVM_SYSTEM_TIME MSR, forcing an update.

Also move restore_sched_clock_state before __restore_processor_state,
since the later calls CONFIG_LOCK_STAT's lockstat_clock (also for TSC).
Thanks to Igor Mammedov for tracking it down.

Fixes suspend-to-disk with kvmclock.

Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>

Diffstat (limited to 'arch/x86/kernel/kvmclock.c')
-rw-r--r--arch/x86/kernel/kvmclock.c11
1 files changed, 11 insertions, 0 deletions
diff --git a/arch/x86/kernel/kvmclock.c b/arch/x86/kernel/kvmclock.c
index ca4e735adc54..f8492da65bfc 100644
--- a/arch/x86/kernel/kvmclock.c
+++ b/arch/x86/kernel/kvmclock.c
@@ -136,6 +136,15 @@ int kvm_register_clock(char *txt)
 	return ret;
 }
 
+static void kvm_save_sched_clock_state(void)
+{
+}
+
+static void kvm_restore_sched_clock_state(void)
+{
+	kvm_register_clock("primary cpu clock, resume");
+}
+
 #ifdef CONFIG_X86_LOCAL_APIC
 static void __cpuinit kvm_setup_secondary_clock(void)
 {
@@ -195,6 +204,8 @@ void __init kvmclock_init(void)
 	x86_cpuinit.early_percpu_clock_init =
 		kvm_setup_secondary_clock;
 #endif
+	x86_platform.save_sched_clock_state = kvm_save_sched_clock_state;
+	x86_platform.restore_sched_clock_state = kvm_restore_sched_clock_state;
 	machine_ops.shutdown  = kvm_shutdown;
 #ifdef CONFIG_KEXEC
 	machine_ops.crash_shutdown  = kvm_crash_shutdown;