Rename CHECKPOINT_FLUSH_ALL to CHECKPOINT_FLUSH_UNLOGGED.

The new name more accurately relects the effects of this flag on a
requested checkpoint.  Checkpoint-related log messages (i.e., those
controlled by the log_checkpoints configuration parameter) will now
say "flush-unlogged" instead of "flush-all", too.  This is
preparatory work for a follow-up commit that will add a
FLUSH_UNLOGGED option to the CHECKPOINT command.

Author: Christoph Berg <myon@debian.org>
Discussion: https://postgr.es/m/aDnaKTEf-0dLiEfz%40msg.df7cb.de

src/backend/access/transam/xlog.c

@@ -6828,7 +6828,7 @@ LogCheckpointStart(int flags, bool restartpoint)
 						(flags & CHECKPOINT_WAIT) ? " wait" : "",
 						(flags & CHECKPOINT_CAUSE_XLOG) ? " wal" : "",
 						(flags & CHECKPOINT_CAUSE_TIME) ? " time" : "",
-						(flags & CHECKPOINT_FLUSH_ALL) ? " flush-all" : "")));
+						(flags & CHECKPOINT_FLUSH_UNLOGGED) ? " flush-unlogged" : "")));
 	else
 		ereport(LOG,
 		/* translator: the placeholders show checkpoint options */
@@ -6840,7 +6840,7 @@ LogCheckpointStart(int flags, bool restartpoint)
 						(flags & CHECKPOINT_WAIT) ? " wait" : "",
 						(flags & CHECKPOINT_CAUSE_XLOG) ? " wal" : "",
 						(flags & CHECKPOINT_CAUSE_TIME) ? " time" : "",
-						(flags & CHECKPOINT_FLUSH_ALL) ? " flush-all" : "")));
+						(flags & CHECKPOINT_FLUSH_UNLOGGED) ? " flush-unlogged" : "")));
 }
 
 /*
@@ -7028,7 +7028,7 @@ update_checkpoint_display(int flags, bool restartpoint, bool reset)
  *	CHECKPOINT_FORCE: force a checkpoint even if no XLOG activity has occurred
  *		since the last one (implied by CHECKPOINT_IS_SHUTDOWN or
  *		CHECKPOINT_END_OF_RECOVERY).
- *	CHECKPOINT_FLUSH_ALL: also flush buffers of unlogged tables.
+ *	CHECKPOINT_FLUSH_UNLOGGED: also flush buffers of unlogged tables.
  *
  * Note: flags contains other bits, of interest here only for logging purposes.
  * In particular note that this routine is synchronous and does not pay

src/backend/commands/dbcommands.c

@@ -571,7 +571,7 @@ CreateDatabaseUsingFileCopy(Oid src_dboid, Oid dst_dboid, Oid src_tsid,
 	 */
 	if (!IsBinaryUpgrade)
 		RequestCheckpoint(CHECKPOINT_IMMEDIATE | CHECKPOINT_FORCE |
-						  CHECKPOINT_WAIT | CHECKPOINT_FLUSH_ALL);
+						  CHECKPOINT_WAIT | CHECKPOINT_FLUSH_UNLOGGED);
 
 	/*
 	 * Iterate through all tablespaces of the template database, and copy each
@@ -2121,7 +2121,7 @@ movedb(const char *dbname, const char *tblspcname)
 	 * files, which would cause rmdir() to fail.
 	 */
 	RequestCheckpoint(CHECKPOINT_IMMEDIATE | CHECKPOINT_FORCE | CHECKPOINT_WAIT
-					  | CHECKPOINT_FLUSH_ALL);
+					  | CHECKPOINT_FLUSH_UNLOGGED);
 
 	/* Close all smgr fds in all backends. */
 	WaitForProcSignalBarrier(EmitProcSignalBarrier(PROCSIGNAL_BARRIER_SMGRRELEASE));

src/backend/storage/buffer/bufmgr.c

@@ -3341,8 +3341,8 @@ UnpinBufferNoOwner(BufferDesc *buf)
  * This is called at checkpoint time to write out all dirty shared buffers.
  * The checkpoint request flags should be passed in.  If CHECKPOINT_IMMEDIATE
  * is set, we disable delays between writes; if CHECKPOINT_IS_SHUTDOWN,
- * CHECKPOINT_END_OF_RECOVERY or CHECKPOINT_FLUSH_ALL is set, we write even
- * unlogged buffers, which are otherwise skipped.  The remaining flags
+ * CHECKPOINT_END_OF_RECOVERY or CHECKPOINT_FLUSH_UNLOGGED is set, we write
+ * even unlogged buffers, which are otherwise skipped.  The remaining flags
  * currently have no effect here.
  */
 static void
@@ -3367,7 +3367,7 @@ BufferSync(int flags)
 	 * recovery, we write all dirty buffers.
 	 */
 	if (!((flags & (CHECKPOINT_IS_SHUTDOWN | CHECKPOINT_END_OF_RECOVERY |
-					CHECKPOINT_FLUSH_ALL))))
+					CHECKPOINT_FLUSH_UNLOGGED))))
 		mask |= BM_PERMANENT;
 
 	/*

src/include/access/xlog.h

@@ -141,8 +141,7 @@ extern PGDLLIMPORT bool XLOG_DEBUG;
 											 * issued at end of WAL recovery */
 #define CHECKPOINT_IMMEDIATE	0x0004	/* Do it without delays */
 #define CHECKPOINT_FORCE		0x0008	/* Force even if no activity */
-#define CHECKPOINT_FLUSH_ALL	0x0010	/* Flush all pages, including those
-										 * belonging to unlogged tables */
+#define CHECKPOINT_FLUSH_UNLOGGED	0x0010	/* Flush unlogged tables */
 /* These are important to RequestCheckpoint */
 #define CHECKPOINT_WAIT			0x0020	/* Wait for completion */
 #define CHECKPOINT_REQUESTED	0x0040	/* Checkpoint request has been made */