summaryrefslogtreecommitdiff
path: root/arch/x86/kernel/kvmclock.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/x86/kernel/kvmclock.c')
-rw-r--r--arch/x86/kernel/kvmclock.c20
1 files changed, 20 insertions, 0 deletions
diff --git a/arch/x86/kernel/kvmclock.c b/arch/x86/kernel/kvmclock.c
index f8492da65bfc..086eb58c6e80 100644
--- a/arch/x86/kernel/kvmclock.c
+++ b/arch/x86/kernel/kvmclock.c
@@ -22,6 +22,7 @@
#include <asm/msr.h>
#include <asm/apic.h>
#include <linux/percpu.h>
+#include <linux/hardirq.h>
#include <asm/x86_init.h>
#include <asm/reboot.h>
@@ -114,6 +115,25 @@ static void kvm_get_preset_lpj(void)
preset_lpj = lpj;
}
+bool kvm_check_and_clear_guest_paused(void)
+{
+ bool ret = false;
+ struct pvclock_vcpu_time_info *src;
+
+ /*
+ * per_cpu() is safe here because this function is only called from
+ * timer functions where preemption is already disabled.
+ */
+ WARN_ON(!in_atomic());
+ src = &__get_cpu_var(hv_clock);
+ if ((src->flags & PVCLOCK_GUEST_STOPPED) != 0) {
+ __this_cpu_and(hv_clock.flags, ~PVCLOCK_GUEST_STOPPED);
+ ret = true;
+ }
+
+ return ret;
+}
+
static struct clocksource kvm_clock = {
.name = "kvm-clock",
.read = kvm_clock_get_cycles,