2.6.35-longterm review patch. If anyone has any objections, please let me know.
------------------ From: Jeremy Fitzhardinge <[email protected]> commit e7a3481c0246c8e45e79c629efd63b168e91fcda upstream. If the guest domain has been suspend/resumed or migrated, then the system clock backing the pvclock clocksource may revert to a smaller value (ie, can be non-monotonic across the migration/save-restore). Make sure we zero last_value in that case so that the domain continues to see clock updates. Signed-off-by: Jeremy Fitzhardinge <[email protected]> Signed-off-by: Ingo Molnar <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> Signed-off-by: Andi Kleen <[email protected]> --- arch/x86/include/asm/pvclock.h | 1 + arch/x86/kernel/pvclock.c | 5 +++++ arch/x86/xen/time.c | 2 ++ 3 files changed, 8 insertions(+) Index: linux-2.6.35.y/arch/x86/include/asm/pvclock.h =================================================================== --- linux-2.6.35.y.orig/arch/x86/include/asm/pvclock.h 2011-03-29 22:51:22.108157477 -0700 +++ linux-2.6.35.y/arch/x86/include/asm/pvclock.h 2011-03-29 23:03:00.598284861 -0700 @@ -11,5 +11,6 @@ void pvclock_read_wallclock(struct pvclock_wall_clock *wall, struct pvclock_vcpu_time_info *vcpu, struct timespec *ts); +void pvclock_resume(void); #endif /* _ASM_X86_PVCLOCK_H */ Index: linux-2.6.35.y/arch/x86/kernel/pvclock.c =================================================================== --- linux-2.6.35.y.orig/arch/x86/kernel/pvclock.c 2011-03-29 22:51:22.108157477 -0700 +++ linux-2.6.35.y/arch/x86/kernel/pvclock.c 2011-03-29 23:03:00.598284861 -0700 @@ -120,6 +120,11 @@ static atomic64_t last_value = ATOMIC64_INIT(0); +void pvclock_resume(void) +{ + atomic64_set(&last_value, 0); +} + cycle_t pvclock_clocksource_read(struct pvclock_vcpu_time_info *src) { struct pvclock_shadow_time shadow; Index: linux-2.6.35.y/arch/x86/xen/time.c =================================================================== --- linux-2.6.35.y.orig/arch/x86/xen/time.c 2011-03-29 22:51:22.109157451 -0700 +++ linux-2.6.35.y/arch/x86/xen/time.c 2011-03-29 23:03:00.629284080 -0700 @@ -425,6 +425,8 @@ { int cpu; + pvclock_resume(); + if (xen_clockevent != &xen_vcpuop_clockevent) return; _______________________________________________ stable mailing list [email protected] http://linux.kernel.org/mailman/listinfo/stable
