diff options
Diffstat (limited to 'arch/x86/kernel/kvmclock.c')
-rw-r--r-- | arch/x86/kernel/kvmclock.c | 21 |
1 files changed, 21 insertions, 0 deletions
diff --git a/arch/x86/kernel/kvmclock.c b/arch/x86/kernel/kvmclock.c index f8492da65bfc..4ba090ca689d 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 +115,26 @@ 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; +} +EXPORT_SYMBOL_GPL(kvm_check_and_clear_guest_paused); + static struct clocksource kvm_clock = { .name = "kvm-clock", .read = kvm_clock_get_cycles, |