From: Robert Haas <rhaas@postgresql.org>
Date: Thu, 23 Sep 2021 17:11:51 +0000 (-0400)
Subject: remove some excess parens. rearrange lock ordering slightly.
X-Git-Url: http://git.postgresql.org/gitweb/static/gitweb.js?a=commitdiff_plain;h=e58f2e12735f7bb0fbc2799698b6955faa5cac53;p=users%2Frhaas%2Fpostgres.git

remove some excess parens. rearrange lock ordering slightly.
---

diff --git a/src/backend/access/conveyor/conveyor.c b/src/backend/access/conveyor/conveyor.c
index 7261c48c12..47aa979a0e 100644
--- a/src/backend/access/conveyor/conveyor.c
+++ b/src/backend/access/conveyor/conveyor.c
@@ -280,8 +280,8 @@ ConveyorBeltGetNewPage(ConveyorBelt *cb, CBPageNo *pageno)
 			(insert_state == CBM_INSERT_NEEDS_PAYLOAD_SEGMENT
 			 || insert_state == CBM_INSERT_NEEDS_INDEX_SEGMENT) &&
 			mode == BUFFER_LOCK_EXCLUSIVE &&
-			(free_segno != CB_INVALID_SEGMENT) &&
-			(free_segno < possibly_not_on_disk_segno);
+			free_segno != CB_INVALID_SEGMENT &&
+			free_segno < possibly_not_on_disk_segno;
 
 		/*
 		 * If it still looks like we can allocate, check for the case where we
@@ -421,11 +421,17 @@ ConveyorBeltGetNewPage(ConveyorBelt *cb, CBPageNo *pageno)
 											next_blkno, nblocks));
 				else if (next_blkno == nblocks)
 				{
+					/* relase extension lock before locking buffer */
 					buffer = ReadBufferExtended(cb->cb_rel, cb->cb_fork,
 												P_NEW, RBM_NORMAL, NULL);
+					UnlockRelationForExtension(cb->cb_rel, ExclusiveLock);
 					LockBuffer(buffer, BUFFER_LOCK_EXCLUSIVE);
 				}
-				UnlockRelationForExtension(cb->cb_rel, ExclusiveLock);
+				else
+				{
+					/* we don't need to extend */
+					UnlockRelationForExtension(cb->cb_rel, ExclusiveLock);
+				}
 			}
 
 			/* If we didn't extend the relation, just read the buffer. */