From b74f05d61b73af584d0c39121980171389ecfaaa Mon Sep 17 00:00:00 2001 From: Marcelo Tosatti Date: Mon, 13 Feb 2012 11:07:27 -0200 Subject: 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 Signed-off-by: Marcelo Tosatti Signed-off-by: Avi Kivity --- arch/x86/kernel/kvmclock.c | 11 +++++++++++ arch/x86/kernel/tsc.c | 4 ++-- arch/x86/kernel/x86_init.c | 4 +++- 3 files changed, 16 insertions(+), 3 deletions(-) (limited to 'arch/x86/kernel') 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; diff --git a/arch/x86/kernel/tsc.c b/arch/x86/kernel/tsc.c index a62c201c97ec..aed2aa1088f1 100644 --- a/arch/x86/kernel/tsc.c +++ b/arch/x86/kernel/tsc.c @@ -629,7 +629,7 @@ static void set_cyc2ns_scale(unsigned long cpu_khz, int cpu) static unsigned long long cyc2ns_suspend; -void save_sched_clock_state(void) +void tsc_save_sched_clock_state(void) { if (!sched_clock_stable) return; @@ -645,7 +645,7 @@ void save_sched_clock_state(void) * that sched_clock() continues from the point where it was left off during * suspend. */ -void restore_sched_clock_state(void) +void tsc_restore_sched_clock_state(void) { unsigned long long offset; unsigned long flags; diff --git a/arch/x86/kernel/x86_init.c b/arch/x86/kernel/x86_init.c index 6f2ec53deed0..e9f265fd79ae 100644 --- a/arch/x86/kernel/x86_init.c +++ b/arch/x86/kernel/x86_init.c @@ -108,7 +108,9 @@ struct x86_platform_ops x86_platform = { .is_untracked_pat_range = is_ISA_range, .nmi_init = default_nmi_init, .get_nmi_reason = default_get_nmi_reason, - .i8042_detect = default_i8042_detect + .i8042_detect = default_i8042_detect, + .save_sched_clock_state = tsc_save_sched_clock_state, + .restore_sched_clock_state = tsc_restore_sched_clock_state, }; EXPORT_SYMBOL_GPL(x86_platform); -- cgit v1.2.3