branches/innodb+: Merge revisions 3519:3541 from branches/zip:

  ------------------------------------------------------------------------
  r3537 | marko | 2008-12-16 10:24:03 +0200 (Tue, 16 Dec 2008) | 3 lines

  branches/zip: sync_thread_add_level(): Add a comment explaining the
  assertion about SYNC_BUF_POOL and SYNC_BUF_BLOCK.
  ------------------------------------------------------------------------
  r3540 | marko | 2008-12-16 12:13:31 +0200 (Tue, 16 Dec 2008) | 2 lines

  branches/zip: buf_page_init_for_read(): Use common code for error exit.
  ------------------------------------------------------------------------
  r3541 | marko | 2008-12-16 12:14:58 +0200 (Tue, 16 Dec 2008) | 3 lines

  branches/zip: btr_cur_optimistic_delete(): Note that no further pages
  must be latched before calling mtr_commit(mtr) if the function returns TRUE.
  ------------------------------------------------------------------------

btr/btr0cur.c

@@ -2863,7 +2863,10 @@ btr_cur_optimistic_delete(
 				delete; cursor stays valid: if deletion
 				succeeds, on function exit it points to the
 				successor of the deleted record */
-	mtr_t*		mtr)	/* in: mtr */
+	mtr_t*		mtr)	/* in: mtr; if this function returns
+				TRUE on a leaf page of a secondary
+				index, the mtr must be committed
+				before latching any further pages */
 {
 	buf_block_t*	block;
 	rec_t*		rec;

buf/buf0buf.c

@@ -2694,15 +2694,8 @@ buf_page_init_for_read(
 			mutex_exit(&block->mutex);
 		}
 
-err_exit2:
-		buf_pool_mutex_exit();
-
-		if (mode == BUF_READ_IBUF_PAGES_ONLY) {
-
-			mtr_commit(&mtr);
-		}
-
-		return(NULL);
+		bpage = NULL;
+		goto func_exit;
 	}
 
 	if (fil_tablespace_deleted_or_being_deleted_in_mem(
@@ -2783,7 +2776,9 @@ buf_page_init_for_read(
 			/* The block was added by some other thread. */
 			buf_buddy_free(bpage, sizeof *bpage);
 			buf_buddy_free(data, zip_size);
-			goto err_exit2;
+
+			bpage = NULL;
+			goto func_exit;
 		}
 
 		page_zip_des_init(&bpage->zip);
@@ -2824,6 +2819,7 @@ buf_page_init_for_read(
 	}
 
 	buf_pool->n_pend_reads++;
+func_exit:
 	buf_pool_mutex_exit();
 
 	if (mode == BUF_READ_IBUF_PAGES_ONLY) {
@@ -2831,7 +2827,7 @@ buf_page_init_for_read(
 		mtr_commit(&mtr);
 	}
 
-	ut_ad(buf_page_in_file(bpage));
+	ut_ad(!bpage || buf_page_in_file(bpage));
 	return(bpage);
 }
 

include/btr0cur.h

@@ -340,7 +340,10 @@ btr_cur_optimistic_delete(
 				cursor stays valid: if deletion succeeds,
 				on function exit it points to the successor
 				of the deleted record */
-	mtr_t*		mtr);	/* in: mtr */
+	mtr_t*		mtr);	/* in: mtr; if this function returns
+				TRUE on a leaf page of a secondary
+				index, the mtr must be committed
+				before latching any further pages */
 /*****************************************************************
 Removes the record on which the tree cursor is positioned. Tries
 to compress the page if its fillfactor drops below a threshold

sync/sync0sync.c

@@ -1079,6 +1079,9 @@ sync_thread_add_level(
 		}
 		break;
 	case SYNC_BUF_BLOCK:
+		/* Either the thread must own the buffer pool mutex
+		(buf_pool_mutex), or it is allowed to latch only ONE
+		buffer block (block->mutex or buf_pool_zip_mutex). */
 		ut_a((sync_thread_levels_contain(array, SYNC_BUF_POOL)
 		      && sync_thread_levels_g(array, SYNC_BUF_BLOCK - 1))
 		     || sync_thread_levels_g(array, SYNC_BUF_BLOCK));