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>

*** 18,28 ****
   *
   * CDDL HEADER END
   */
  /*
   * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
!  * Copyright (c) 2012 by Delphix. All rights reserved.
   * Copyright 2011 Nexenta Systems, Inc.  All rights reserved.
   */
  
  #ifndef _SYS_SPA_IMPL_H
  #define _SYS_SPA_IMPL_H
--- 18,28 ----
   *
   * CDDL HEADER END
   */
  /*
   * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
!  * Copyright (c) 2013 by Delphix. All rights reserved.
   * Copyright 2011 Nexenta Systems, Inc.  All rights reserved.
   */
  
  #ifndef _SYS_SPA_IMPL_H
  #define _SYS_SPA_IMPL_H
*** 232,246 ****
          uint64_t        spa_feat_for_write_obj; /* required to write to pool */
          uint64_t        spa_feat_for_read_obj;  /* required to read from pool */
          uint64_t        spa_feat_desc_obj;      /* Feature descriptions */
          cyclic_id_t     spa_deadman_cycid;      /* cyclic id */
          uint64_t        spa_deadman_calls;      /* number of deadman calls */
!         uint64_t        spa_sync_starttime;     /* starting time fo spa_sync */
          uint64_t        spa_deadman_synctime;   /* deadman expiration timer */
!         kmutex_t        spa_iokstat_lock;       /* protects spa_iokstat_* */
          struct kstat    *spa_iokstat;           /* kstat of io to this pool */
          hrtime_t        spa_ccw_fail_time;      /* Conf cache write fail time */
          /*
           * spa_refcount & spa_config_lock must be the last elements
           * because refcount_t changes size based on compilation options.
           * In order for the MDB module to function correctly, the other
           * fields must remain in the same location.
--- 232,257 ----
          uint64_t        spa_feat_for_write_obj; /* required to write to pool */
          uint64_t        spa_feat_for_read_obj;  /* required to read from pool */
          uint64_t        spa_feat_desc_obj;      /* Feature descriptions */
          cyclic_id_t     spa_deadman_cycid;      /* cyclic id */
          uint64_t        spa_deadman_calls;      /* number of deadman calls */
!         hrtime_t        spa_sync_starttime;     /* starting time fo spa_sync */
          uint64_t        spa_deadman_synctime;   /* deadman expiration timer */
! 
!         /*
!          * spa_iokstat_lock protects spa_iokstat and
!          * spa_queue_stats[].
!          */
!         kmutex_t        spa_iokstat_lock;
          struct kstat    *spa_iokstat;           /* kstat of io to this pool */
+         struct {
+                 int spa_active;
+                 int spa_queued;
+         } spa_queue_stats[ZIO_PRIORITY_NUM_QUEUEABLE];
+ 
          hrtime_t        spa_ccw_fail_time;      /* Conf cache write fail time */
+ 
          /*
           * spa_refcount & spa_config_lock must be the last elements
           * because refcount_t changes size based on compilation options.
           * In order for the MDB module to function correctly, the other
           * fields must remain in the same location.