3006 VERIFY[S,U,P] and ASSERT[S,U,P] frequently check if first argument is zero

*** 1008,1018 ****
                  ASSERT(!MUTEX_HELD(&ab->b_state->arcs_mtx));
                  mutex_enter(&ab->b_state->arcs_mtx);
                  ASSERT(list_link_active(&ab->b_arc_node));
                  list_remove(list, ab);
                  if (GHOST_STATE(ab->b_state)) {
!                         ASSERT3U(ab->b_datacnt, ==, 0);
                          ASSERT3P(ab->b_buf, ==, NULL);
                          delta = ab->b_size;
                  }
                  ASSERT(delta > 0);
                  ASSERT3U(*size, >=, delta);
--- 1008,1018 ----
                  ASSERT(!MUTEX_HELD(&ab->b_state->arcs_mtx));
                  mutex_enter(&ab->b_state->arcs_mtx);
                  ASSERT(list_link_active(&ab->b_arc_node));
                  list_remove(list, ab);
                  if (GHOST_STATE(ab->b_state)) {
!                         ASSERT0(ab->b_datacnt);
                          ASSERT3P(ab->b_buf, ==, NULL);
                          delta = ab->b_size;
                  }
                  ASSERT(delta > 0);
                  ASSERT3U(*size, >=, delta);
*** 1635,1645 ****
                      ab_prev && ab_prev->b_size == bytes)
                          continue;
                  hash_lock = HDR_LOCK(ab);
                  have_lock = MUTEX_HELD(hash_lock);
                  if (have_lock || mutex_tryenter(hash_lock)) {
!                         ASSERT3U(refcount_count(&ab->b_refcnt), ==, 0);
                          ASSERT(ab->b_datacnt > 0);
                          while (ab->b_buf) {
                                  arc_buf_t *buf = ab->b_buf;
                                  if (!mutex_tryenter(&buf->b_evict_lock)) {
                                          missed += 1;
--- 1635,1645 ----
                      ab_prev && ab_prev->b_size == bytes)
                          continue;
                  hash_lock = HDR_LOCK(ab);
                  have_lock = MUTEX_HELD(hash_lock);
                  if (have_lock || mutex_tryenter(hash_lock)) {
!                         ASSERT0(refcount_count(&ab->b_refcnt));
                          ASSERT(ab->b_datacnt > 0);
                          while (ab->b_buf) {
                                  arc_buf_t *buf = ab->b_buf;
                                  if (!mutex_tryenter(&buf->b_evict_lock)) {
                                          missed += 1;
*** 2463,2473 ****
                  if (buf->b_flags & ARC_PREFETCH) {
                          /*
                           * This is a prefetch access...
                           * move this block back to the MRU state.
                           */
!                         ASSERT3U(refcount_count(&buf->b_refcnt), ==, 0);
                          new_state = arc_mru;
                  }
  
                  buf->b_arc_access = ddi_get_lbolt();
                  DTRACE_PROBE1(new_state__mfu, arc_buf_hdr_t *, buf);
--- 2463,2473 ----
                  if (buf->b_flags & ARC_PREFETCH) {
                          /*
                           * This is a prefetch access...
                           * move this block back to the MRU state.
                           */
!                         ASSERT0(refcount_count(&buf->b_refcnt));
                          new_state = arc_mru;
                  }
  
                  buf->b_arc_access = ddi_get_lbolt();
                  DTRACE_PROBE1(new_state__mfu, arc_buf_hdr_t *, buf);
*** 2804,2814 ****
                                  hdr->b_flags |= ARC_INDIRECT;
                  } else {
                          /* this block is in the ghost cache */
                          ASSERT(GHOST_STATE(hdr->b_state));
                          ASSERT(!HDR_IO_IN_PROGRESS(hdr));
!                         ASSERT3U(refcount_count(&hdr->b_refcnt), ==, 0);
                          ASSERT(hdr->b_buf == NULL);
  
                          /* if this is a prefetch, we don't have a reference */
                          if (*arc_flags & ARC_PREFETCH)
                                  hdr->b_flags |= ARC_PREFETCH;
--- 2804,2814 ----
                                  hdr->b_flags |= ARC_INDIRECT;
                  } else {
                          /* this block is in the ghost cache */
                          ASSERT(GHOST_STATE(hdr->b_state));
                          ASSERT(!HDR_IO_IN_PROGRESS(hdr));
!                         ASSERT0(refcount_count(&hdr->b_refcnt));
                          ASSERT(hdr->b_buf == NULL);
  
                          /* if this is a prefetch, we don't have a reference */
                          if (*arc_flags & ARC_PREFETCH)
                                  hdr->b_flags |= ARC_PREFETCH;
*** 4378,4388 ****
                          break;
          }
          mutex_exit(&l2arc_buflist_mtx);
  
          if (pio == NULL) {
!                 ASSERT3U(write_sz, ==, 0);
                  kmem_cache_free(hdr_cache, head);
                  return (0);
          }
  
          ASSERT3U(write_sz, <=, target_sz);
--- 4378,4388 ----
                          break;
          }
          mutex_exit(&l2arc_buflist_mtx);
  
          if (pio == NULL) {
!                 ASSERT0(write_sz);
                  kmem_cache_free(hdr_cache, head);
                  return (0);
          }
  
          ASSERT3U(write_sz, <=, target_sz);