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yaml
---
r: 343531
b: refs/heads/master
c: 7069ed6
h: refs/heads/master
i:
  343529: a893c84
  343527: 96f540b
v: v3
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Marcelo Tosatti committed Nov 28, 2012
1 parent 8763ea3 commit 436b4ba
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Showing 2 changed files with 48 additions and 12 deletions.
2 changes: 1 addition & 1 deletion [refs]
Original file line number Diff line number Diff line change
@@ -1,2 +1,2 @@
---
refs/heads/master: 78c0337a38450f809113dd46fe038874b93909f1
refs/heads/master: 7069ed67635b8d574541af426d752cd7fbd465a6
58 changes: 47 additions & 11 deletions trunk/arch/x86/kernel/kvmclock.c
Original file line number Diff line number Diff line change
Expand Up @@ -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>
Expand All @@ -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;

/*
Expand All @@ -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;
}
Expand All @@ -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;
Expand All @@ -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)
Expand All @@ -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;
}

Expand All @@ -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);
Expand Down Expand Up @@ -197,6 +221,8 @@ static void kvm_shutdown(void)

void __init kvmclock_init(void)
{
unsigned long mem;

if (!kvm_para_available())
return;

Expand All @@ -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;
Expand Down

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