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;