1 files changed, 9 insertions, 123 deletions

diff --git a/sys/dev/xen/timer/timer.c b/sys/dev/xen/timer/timer.c
index 5743076..53aff0a 100644
--- a/sys/dev/xen/timer/timer.c
+++ b/sys/dev/xen/timer/timer.c
@@ -59,6 +59,7 @@ __FBSDID("$FreeBSD$");
 #include <machine/clock.h>
 #include <machine/_inttypes.h>
 #include <machine/smp.h>
+#include <machine/pvclock.h>
 
 #include <dev/xen/timer/timer.h>
 
@@ -95,9 +96,6 @@ struct xentimer_softc {
 	struct eventtimer et;
 };
 
-/* Last time; this guarantees a monotonically increasing clock. */
-volatile uint64_t xen_timer_last_time = 0;
-
 static void
 xentimer_identify(driver_t *driver, device_t parent)
 {
@@ -148,128 +146,20 @@ xentimer_probe(device_t dev)
 	return (BUS_PROBE_NOWILDCARD);
 }
 
-/*
- * Scale a 64-bit delta by scaling and multiplying by a 32-bit fraction,
- * yielding a 64-bit result.
- */
-static inline uint64_t
-scale_delta(uint64_t delta, uint32_t mul_frac, int shift)
-{
-	uint64_t product;
-
-	if (shift < 0)
-		delta >>= -shift;
-	else
-		delta <<= shift;
-
-#if defined(__i386__)
-	{
-		uint32_t tmp1, tmp2;
-
-		/**
-		 * For i386, the formula looks like:
-		 *
-		 *   lower = (mul_frac * (delta & UINT_MAX)) >> 32
-		 *   upper = mul_frac * (delta >> 32)
-		 *   product = lower + upper
-		 */
-		__asm__ (
-			"mul  %5       ; "
-			"mov  %4,%%eax ; "
-			"mov  %%edx,%4 ; "
-			"mul  %5       ; "
-			"xor  %5,%5    ; "
-			"add  %4,%%eax ; "
-			"adc  %5,%%edx ; "
-			: "=A" (product), "=r" (tmp1), "=r" (tmp2)
-			: "a" ((uint32_t)delta), "1" ((uint32_t)(delta >> 32)),
-			  "2" (mul_frac) );
-	}
-#elif defined(__amd64__)
-	{
-		unsigned long tmp;
-
-		__asm__ (
-			"mulq %[mul_frac] ; shrd $32, %[hi], %[lo]"
-			: [lo]"=a" (product), [hi]"=d" (tmp)
-			: "0" (delta), [mul_frac]"rm"((uint64_t)mul_frac));
-	}
-#else
-#error "xentimer: unsupported architecture"
-#endif
-
-	return (product);
-}
-
-static uint64_t
-get_nsec_offset(struct vcpu_time_info *tinfo)
-{
-
-	return (scale_delta(rdtsc() - tinfo->tsc_timestamp,
-	    tinfo->tsc_to_system_mul, tinfo->tsc_shift));
-}
-
-/*
- * Read the current hypervisor system uptime value from Xen.
- * See <xen/interface/xen.h> for a description of how this works.
- */
-static uint32_t
-xen_fetch_vcpu_tinfo(struct vcpu_time_info *dst, struct vcpu_time_info *src)
-{
-
-	do {
-		dst->version = src->version;
-		rmb();
-		dst->tsc_timestamp = src->tsc_timestamp;
-		dst->system_time = src->system_time;
-		dst->tsc_to_system_mul = src->tsc_to_system_mul;
-		dst->tsc_shift = src->tsc_shift;
-		rmb();
-	} while ((src->version & 1) | (dst->version ^ src->version));
-
-	return (dst->version);
-}
-
 /**
  * \brief Get the current time, in nanoseconds, since the hypervisor booted.
  *
  * \param vcpu		vcpu_info structure to fetch the time from.
  *
- * \note This function returns the current CPU's idea of this value, unless
- *       it happens to be less than another CPU's previously determined value.
  */
 static uint64_t
 xen_fetch_vcpu_time(struct vcpu_info *vcpu)
 {
-	struct vcpu_time_info dst;
-	struct vcpu_time_info *src;
-	uint32_t pre_version;
-	uint64_t now;
-	volatile uint64_t last;
-
-	src = &vcpu->time;
-
-	do {
-		pre_version = xen_fetch_vcpu_tinfo(&dst, src);
-		barrier();
-		now = dst.system_time + get_nsec_offset(&dst);
-		barrier();
-	} while (pre_version != src->version);
+	struct pvclock_vcpu_time_info *time;
 
-	/*
-	 * Enforce a monotonically increasing clock time across all
-	 * VCPUs.  If our time is too old, use the last time and return.
-	 * Otherwise, try to update the last time.
-	 */
-	do {
-		last = xen_timer_last_time;
-		if (last > now) {
-			now = last;
-			break;
-		}
-	} while (!atomic_cmpset_64(&xen_timer_last_time, last, now));
+	time = (struct pvclock_vcpu_time_info *) &vcpu->time;
 
-	return (now);
+	return (pvclock_get_timecount(time));
 }
 
 static uint32_t
@@ -302,15 +192,11 @@ static void
 xen_fetch_wallclock(struct timespec *ts)
 {
 	shared_info_t *src = HYPERVISOR_shared_info;
-	uint32_t version = 0;
+	struct pvclock_wall_clock *wc;
 
-	do {
-		version = src->wc_version;
-		rmb();
-		ts->tv_sec = src->wc_sec;
-		ts->tv_nsec = src->wc_nsec;
-		rmb();
-	} while ((src->wc_version & 1) | (version ^ src->wc_version));
+	wc = (struct pvclock_wall_clock *) &src->wc_version;
+
+	pvclock_get_wallclock(wc, ts);
 }
 
 static void
@@ -574,7 +460,7 @@ xentimer_resume(device_t dev)
 	}
 
 	/* Reset the last uptime value */
-	xen_timer_last_time = 0;
+	pvclock_resume();
 
 	/* Reset the RTC clock */
 	inittodr(time_second);