summaryrefslogtreecommitdiff
path: root/arch/x86/xen/time.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/x86/xen/time.c')
-rw-r--r--arch/x86/xen/time.c115
1 files changed, 31 insertions, 84 deletions
diff --git a/arch/x86/xen/time.c b/arch/x86/xen/time.c
index f1ba6a092..a0a4e554c 100644
--- a/arch/x86/xen/time.c
+++ b/arch/x86/xen/time.c
@@ -16,6 +16,7 @@
#include <linux/gfp.h>
#include <linux/slab.h>
#include <linux/pvclock_gtod.h>
+#include <linux/timekeeper_internal.h>
#include <asm/pvclock.h>
#include <asm/xen/hypervisor.h>
@@ -32,86 +33,12 @@
#define TIMER_SLOP 100000
#define NS_PER_TICK (1000000000LL / HZ)
-/* runstate info updated by Xen */
-static DEFINE_PER_CPU(struct vcpu_runstate_info, xen_runstate);
-
/* snapshots of runstate info */
static DEFINE_PER_CPU(struct vcpu_runstate_info, xen_runstate_snapshot);
/* unused ns of stolen time */
static DEFINE_PER_CPU(u64, xen_residual_stolen);
-/* return an consistent snapshot of 64-bit time/counter value */
-static u64 get64(const u64 *p)
-{
- u64 ret;
-
- if (BITS_PER_LONG < 64) {
- u32 *p32 = (u32 *)p;
- u32 h, l;
-
- /*
- * Read high then low, and then make sure high is
- * still the same; this will only loop if low wraps
- * and carries into high.
- * XXX some clean way to make this endian-proof?
- */
- do {
- h = p32[1];
- barrier();
- l = p32[0];
- barrier();
- } while (p32[1] != h);
-
- ret = (((u64)h) << 32) | l;
- } else
- ret = *p;
-
- return ret;
-}
-
-/*
- * Runstate accounting
- */
-static void get_runstate_snapshot(struct vcpu_runstate_info *res)
-{
- u64 state_time;
- struct vcpu_runstate_info *state;
-
- BUG_ON(preemptible());
-
- state = this_cpu_ptr(&xen_runstate);
-
- /*
- * The runstate info is always updated by the hypervisor on
- * the current CPU, so there's no need to use anything
- * stronger than a compiler barrier when fetching it.
- */
- do {
- state_time = get64(&state->state_entry_time);
- barrier();
- *res = *state;
- barrier();
- } while (get64(&state->state_entry_time) != state_time);
-}
-
-/* return true when a vcpu could run but has no real cpu to run on */
-bool xen_vcpu_stolen(int vcpu)
-{
- return per_cpu(xen_runstate, vcpu).state == RUNSTATE_runnable;
-}
-
-void xen_setup_runstate_info(int cpu)
-{
- struct vcpu_register_runstate_memory_area area;
-
- area.addr.v = &per_cpu(xen_runstate, cpu);
-
- if (HYPERVISOR_vcpu_op(VCPUOP_register_runstate_memory_area,
- cpu, &area))
- BUG();
-}
-
static void do_stolen_accounting(void)
{
struct vcpu_runstate_info state;
@@ -119,7 +46,7 @@ static void do_stolen_accounting(void)
s64 runnable, offline, stolen;
cputime_t ticks;
- get_runstate_snapshot(&state);
+ xen_get_runstate_snapshot(&state);
WARN_ON(state.state != RUNSTATE_running);
@@ -194,26 +121,46 @@ static int xen_pvclock_gtod_notify(struct notifier_block *nb,
unsigned long was_set, void *priv)
{
/* Protected by the calling core code serialization */
- static struct timespec next_sync;
+ static struct timespec64 next_sync;
struct xen_platform_op op;
- struct timespec now;
+ struct timespec64 now;
+ struct timekeeper *tk = priv;
+ static bool settime64_supported = true;
+ int ret;
- now = __current_kernel_time();
+ now.tv_sec = tk->xtime_sec;
+ now.tv_nsec = (long)(tk->tkr_mono.xtime_nsec >> tk->tkr_mono.shift);
/*
* We only take the expensive HV call when the clock was set
* or when the 11 minutes RTC synchronization time elapsed.
*/
- if (!was_set && timespec_compare(&now, &next_sync) < 0)
+ if (!was_set && timespec64_compare(&now, &next_sync) < 0)
return NOTIFY_OK;
- op.cmd = XENPF_settime;
- op.u.settime.secs = now.tv_sec;
- op.u.settime.nsecs = now.tv_nsec;
- op.u.settime.system_time = xen_clocksource_read();
+again:
+ if (settime64_supported) {
+ op.cmd = XENPF_settime64;
+ op.u.settime64.mbz = 0;
+ op.u.settime64.secs = now.tv_sec;
+ op.u.settime64.nsecs = now.tv_nsec;
+ op.u.settime64.system_time = xen_clocksource_read();
+ } else {
+ op.cmd = XENPF_settime32;
+ op.u.settime32.secs = now.tv_sec;
+ op.u.settime32.nsecs = now.tv_nsec;
+ op.u.settime32.system_time = xen_clocksource_read();
+ }
+
+ ret = HYPERVISOR_platform_op(&op);
- (void)HYPERVISOR_dom0_op(&op);
+ if (ret == -ENOSYS && settime64_supported) {
+ settime64_supported = false;
+ goto again;
+ }
+ if (ret < 0)
+ return NOTIFY_BAD;
/*
* Move the next drift compensation time 11 minutes