diff options
Diffstat (limited to 'arch')
-rw-r--r-- | arch/x86/kernel/kvmclock.c | 58 |
1 files changed, 47 insertions, 11 deletions
diff --git a/arch/x86/kernel/kvmclock.c b/arch/x86/kernel/kvmclock.c index f1b42b3a186c..c7d75678886e 100644 --- a/arch/x86/kernel/kvmclock.c +++ b/arch/x86/kernel/kvmclock.c @@ -23,6 +23,7 @@ #include <asm/apic.h> #include <linux/percpu.h> #include <linux/hardirq.h> +#include <linux/memblock.h> #include <asm/x86_init.h> #include <asm/reboot.h> @@ -39,7 +40,11 @@ static int parse_no_kvmclock(char *arg) early_param("no-kvmclock", parse_no_kvmclock); /* The hypervisor will put information about time periodically here */ -static DEFINE_PER_CPU_SHARED_ALIGNED(struct pvclock_vcpu_time_info, hv_clock); +struct pvclock_aligned_vcpu_time_info { + struct pvclock_vcpu_time_info clock; +} __attribute__((__aligned__(SMP_CACHE_BYTES))); + +static struct pvclock_aligned_vcpu_time_info *hv_clock; static struct pvclock_wall_clock wall_clock; /* @@ -52,15 +57,20 @@ static unsigned long kvm_get_wallclock(void) struct pvclock_vcpu_time_info *vcpu_time; struct timespec ts; int low, high; + int cpu; low = (int)__pa_symbol(&wall_clock); high = ((u64)__pa_symbol(&wall_clock) >> 32); native_write_msr(msr_kvm_wall_clock, low, high); - vcpu_time = &get_cpu_var(hv_clock); + preempt_disable(); + cpu = smp_processor_id(); + + vcpu_time = &hv_clock[cpu].clock; pvclock_read_wallclock(&wall_clock, vcpu_time, &ts); - put_cpu_var(hv_clock); + + preempt_enable(); return ts.tv_sec; } @@ -74,9 +84,11 @@ static cycle_t kvm_clock_read(void) { struct pvclock_vcpu_time_info *src; cycle_t ret; + int cpu; preempt_disable_notrace(); - src = &__get_cpu_var(hv_clock); + cpu = smp_processor_id(); + src = &hv_clock[cpu].clock; ret = pvclock_clocksource_read(src); preempt_enable_notrace(); return ret; @@ -99,8 +111,15 @@ static cycle_t kvm_clock_get_cycles(struct clocksource *cs) static unsigned long kvm_get_tsc_khz(void) { struct pvclock_vcpu_time_info *src; - src = &per_cpu(hv_clock, 0); - return pvclock_tsc_khz(src); + int cpu; + unsigned long tsc_khz; + + preempt_disable(); + cpu = smp_processor_id(); + src = &hv_clock[cpu].clock; + tsc_khz = pvclock_tsc_khz(src); + preempt_enable(); + return tsc_khz; } static void kvm_get_preset_lpj(void) @@ -119,10 +138,14 @@ bool kvm_check_and_clear_guest_paused(void) { bool ret = false; struct pvclock_vcpu_time_info *src; + int cpu = smp_processor_id(); + + if (!hv_clock) + return ret; - src = &__get_cpu_var(hv_clock); + src = &hv_clock[cpu].clock; if ((src->flags & PVCLOCK_GUEST_STOPPED) != 0) { - __this_cpu_and(hv_clock.flags, ~PVCLOCK_GUEST_STOPPED); + src->flags &= ~PVCLOCK_GUEST_STOPPED; ret = true; } @@ -141,9 +164,10 @@ int kvm_register_clock(char *txt) { int cpu = smp_processor_id(); int low, high, ret; + struct pvclock_vcpu_time_info *src = &hv_clock[cpu].clock; - low = (int)__pa(&per_cpu(hv_clock, cpu)) | 1; - high = ((u64)__pa(&per_cpu(hv_clock, cpu)) >> 32); + low = (int)__pa(src) | 1; + high = ((u64)__pa(src) >> 32); ret = native_write_msr_safe(msr_kvm_system_time, low, high); printk(KERN_INFO "kvm-clock: cpu %d, msr %x:%x, %s\n", cpu, high, low, txt); @@ -197,6 +221,8 @@ static void kvm_shutdown(void) void __init kvmclock_init(void) { + unsigned long mem; + if (!kvm_para_available()) return; @@ -209,8 +235,18 @@ void __init kvmclock_init(void) printk(KERN_INFO "kvm-clock: Using msrs %x and %x", msr_kvm_system_time, msr_kvm_wall_clock); - if (kvm_register_clock("boot clock")) + mem = memblock_alloc(sizeof(struct pvclock_aligned_vcpu_time_info) * NR_CPUS, + PAGE_SIZE); + if (!mem) + return; + hv_clock = __va(mem); + + if (kvm_register_clock("boot clock")) { + hv_clock = NULL; + memblock_free(mem, + sizeof(struct pvclock_aligned_vcpu_time_info)*NR_CPUS); return; + } pv_time_ops.sched_clock = kvm_clock_read; x86_platform.calibrate_tsc = kvm_get_tsc_khz; x86_platform.get_wallclock = kvm_get_wallclock; |