4764 Need a way to get tsc deltas
Reviewed by: Keith M Wesolowski <wesolows@foobazco.org>
Reviewed by: Josef 'Jeff' Sipek <jeffpc@josefsipek.net>
Reviewed by: Dan McDonald <danmcd@omniti.com>
Reviewed by: Garrett D'Amore <garrett@damore.org>
Approved by: Richard Lowe <richlowe@richlowe.net>

@@ -234,10 +234,23 @@
         } while ((old_hres_lock & ~1) != hres_lock);
 
         return (hrt);
 }
 
+hrtime_t
+tsc_gethrtime_tick_delta(void)
+{
+        hrtime_t hrt;
+        ulong_t flags;
+
+        flags = clear_int_flag();
+        hrt = tsc_sync_tick_delta[CPU->cpu_id];
+        restore_int_flag(flags);
+
+        return (hrt);
+}
+
 /*
  * This is similar to the above, but it cannot actually spin on hres_lock.
  * As a result, it caches all of the variables it needs; if the variables
  * don't change, it's done.
  */