Rearrange _bt_insertonpg() "update metapage" code.

Nest the "update metapage as part of insert into root-like page" branch
inside the broader "insert into internal page" branch.  This improves
readability.

diff --git a/src/backend/access/nbtree/nbtinsert.c b/src/backend/access/nbtree/nbtinsert.c
index 3a7f25df81323695c6f66a15aa55bc408c10528b..c868f6aeccca6e4d3d5cc6a142f45e0d186858fa 100644 (file)
--- a/src/backend/access/nbtree/nbtinsert.c
+++ b/src/backend/access/nbtree/nbtinsert.c
@@ -1306,6 +1306,7 @@ _bt_insertonpg(Relation rel,
                 * Leaf insert with posting list split.  Must include
                 * postingoff field before newitem/orignewitem.
                 */
+               Assert(isleaf);
                xlinfo = XLOG_BTREE_INSERT_POST;
            }
            else
@@ -1313,31 +1314,34 @@ _bt_insertonpg(Relation rel,
                /* Internal page insert, which finishes a split on cbuf */
                xlinfo = XLOG_BTREE_INSERT_UPPER;
                XLogRegisterBuffer(1, cbuf, REGBUF_STANDARD);
-           }
 
-           if (BufferIsValid(metabuf))
-           {
-               Assert(metad->btm_version >= BTREE_NOVAC_VERSION);
-               xlmeta.version = metad->btm_version;
-               xlmeta.root = metad->btm_root;
-               xlmeta.level = metad->btm_level;
-               xlmeta.fastroot = metad->btm_fastroot;
-               xlmeta.fastlevel = metad->btm_fastlevel;
-               xlmeta.oldest_btpo_xact = metad->btm_oldest_btpo_xact;
-               xlmeta.last_cleanup_num_heap_tuples =
-                   metad->btm_last_cleanup_num_heap_tuples;
-               xlmeta.allequalimage = metad->btm_allequalimage;
-
-               XLogRegisterBuffer(2, metabuf, REGBUF_WILL_INIT | REGBUF_STANDARD);
-               XLogRegisterBufData(2, (char *) &xlmeta, sizeof(xl_btree_metadata));
-
-               xlinfo = XLOG_BTREE_INSERT_META;
+               if (BufferIsValid(metabuf))
+               {
+                   /* Actually, it's an internal page insert + meta update */
+                   xlinfo = XLOG_BTREE_INSERT_META;
+
+                   Assert(metad->btm_version >= BTREE_NOVAC_VERSION);
+                   xlmeta.version = metad->btm_version;
+                   xlmeta.root = metad->btm_root;
+                   xlmeta.level = metad->btm_level;
+                   xlmeta.fastroot = metad->btm_fastroot;
+                   xlmeta.fastlevel = metad->btm_fastlevel;
+                   xlmeta.oldest_btpo_xact = metad->btm_oldest_btpo_xact;
+                   xlmeta.last_cleanup_num_heap_tuples =
+                       metad->btm_last_cleanup_num_heap_tuples;
+                   xlmeta.allequalimage = metad->btm_allequalimage;
+
+                   XLogRegisterBuffer(2, metabuf,
+                                      REGBUF_WILL_INIT | REGBUF_STANDARD);
+                   XLogRegisterBufData(2, (char *) &xlmeta,
+                                       sizeof(xl_btree_metadata));
+               }
            }
 
            XLogRegisterBuffer(0, buf, REGBUF_STANDARD);
            if (postingoff == 0)
            {
-               /* Simple, common case -- log itup from caller */
+               /* Just log itup from caller */
                XLogRegisterBufData(0, (char *) itup, IndexTupleSize(itup));
            }
            else