4045 zfs write throttle & i/o scheduler performance work
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Adam Leventhal <ahl@delphix.com>
Reviewed by: Christopher Siden <christopher.siden@delphix.com>

@@ -163,10 +163,12 @@
 /*
  * Threads
  */
 #define curthread       ((void *)(uintptr_t)thr_self())
 
+#define kpreempt(x)     yield()
+
 typedef struct kthread kthread_t;
 
 #define thread_create(stk, stksize, func, arg, len, pp, state, pri)     \
         zk_thread_create(func, arg)
 #define thread_exit() thr_exit(NULL)