]> asedeno.scripts.mit.edu Git - linux.git/blobdiff - arch/x86/include/asm/pvclock.h
Merge remote-tracking branches 'spi/topic/spidev', 'spi/topic/sunxi', 'spi/topic...
[linux.git] / arch / x86 / include / asm / pvclock.h
index fdcc04020636e33269d7a756162cfe852f509823..7c1c89598688bab2edc26dce70ab722e5f79b123 100644 (file)
@@ -68,30 +68,23 @@ static inline u64 pvclock_scale_delta(u64 delta, u32 mul_frac, int shift)
        return product;
 }
 
-static __always_inline
-u64 pvclock_get_nsec_offset(const struct pvclock_vcpu_time_info *src)
-{
-       u64 delta = rdtsc_ordered() - src->tsc_timestamp;
-       return pvclock_scale_delta(delta, src->tsc_to_system_mul,
-                                  src->tsc_shift);
-}
-
 static __always_inline
 unsigned __pvclock_read_cycles(const struct pvclock_vcpu_time_info *src,
                               cycle_t *cycles, u8 *flags)
 {
        unsigned version;
-       cycle_t ret, offset;
-       u8 ret_flags;
+       cycle_t offset;
+       u64 delta;
 
        version = src->version;
+       /* Make the latest version visible */
+       smp_rmb();
 
-       offset = pvclock_get_nsec_offset(src);
-       ret = src->system_time + offset;
-       ret_flags = src->flags;
-
-       *cycles = ret;
-       *flags = ret_flags;
+       delta = rdtsc_ordered() - src->tsc_timestamp;
+       offset = pvclock_scale_delta(delta, src->tsc_to_system_mul,
+                                  src->tsc_shift);
+       *cycles = src->system_time + offset;
+       *flags = src->flags;
        return version;
 }