Remove emode argument from XLogFileRead() and XLogFileReadAnyTLI()

This change makes the code slightly easier to reason about, because
there is actually no need to know if a specific caller of one of these
routines should fail hard on a PANIC, or just let it go through with a
DEBUG2.

The only caller of XLogFileReadAnyTLI() used DEBUG2, and XLogFileRead()
has never used its emode.  This can be simplified since 1bb2558046cc
that has introduced XLogFileReadAnyTLI(), splitting both.

Author: Yugo Nagata
Discussion: https://postgr.es/m/20240906201043.a640f3b44e755d4db2b6943e@sraoss.co.jp

diff --git a/src/backend/access/transam/xlogrecovery.c b/src/backend/access/transam/xlogrecovery.c
index 178491f6f50b6c31e27c28f7676b84580f7508fa..320b14add1ad9a575f7f25c5b68b9d7663744e84 100644 (file)
--- a/src/backend/access/transam/xlogrecovery.c
+++ b/src/backend/access/transam/xlogrecovery.c
@@ -430,9 +430,9 @@ static int  emode_for_corrupt_record(int emode, XLogRecPtr RecPtr);
 static XLogRecord *ReadCheckpointRecord(XLogPrefetcher *xlogprefetcher,
                                                                                XLogRecPtr RecPtr, TimeLineID replayTLI);
 static bool rescanLatestTimeLine(TimeLineID replayTLI, XLogRecPtr replayLSN);
-static int     XLogFileRead(XLogSegNo segno, int emode, TimeLineID tli,
+static int     XLogFileRead(XLogSegNo segno, TimeLineID tli,
                                                 XLogSource source, bool notfoundOk);
-static int     XLogFileReadAnyTLI(XLogSegNo segno, int emode, XLogSource source);
+static int     XLogFileReadAnyTLI(XLogSegNo segno, XLogSource source);
 
 static bool CheckForStandbyTrigger(void);
 static void SetPromoteIsTriggered(void);
@@ -3780,7 +3780,7 @@ WaitForWALToBecomeAvailable(XLogRecPtr RecPtr, bool randAccess,
                                 * Try to restore the file from archive, or read an existing
                                 * file from pg_wal.
                                 */
-                               readFile = XLogFileReadAnyTLI(readSegNo, DEBUG2,
+                               readFile = XLogFileReadAnyTLI(readSegNo,
                                                                                          currentSource == XLOG_FROM_ARCHIVE ? XLOG_FROM_ANY :
                                                                                          currentSource);
                                if (readFile >= 0)
@@ -3929,8 +3929,7 @@ WaitForWALToBecomeAvailable(XLogRecPtr RecPtr, bool randAccess,
                                                {
                                                        if (!expectedTLEs)
                                                                expectedTLEs = readTimeLineHistory(recoveryTargetTLI);
-                                                       readFile = XLogFileRead(readSegNo, PANIC,
-                                                                                                       receiveTLI,
+                                                       readFile = XLogFileRead(readSegNo, receiveTLI,
                                                                                                        XLOG_FROM_STREAM, false);
                                                        Assert(readFile >= 0);
                                                }
@@ -4201,7 +4200,7 @@ rescanLatestTimeLine(TimeLineID replayTLI, XLogRecPtr replayLSN)
  * Otherwise, it's assumed to be already available in pg_wal.
  */
 static int
-XLogFileRead(XLogSegNo segno, int emode, TimeLineID tli,
+XLogFileRead(XLogSegNo segno, TimeLineID tli,
                         XLogSource source, bool notfoundOk)
 {
        char            xlogfname[MAXFNAMELEN];
@@ -4283,7 +4282,7 @@ XLogFileRead(XLogSegNo segno, int emode, TimeLineID tli,
  * This version searches for the segment with any TLI listed in expectedTLEs.
  */
 static int
-XLogFileReadAnyTLI(XLogSegNo segno, int emode, XLogSource source)
+XLogFileReadAnyTLI(XLogSegNo segno, XLogSource source)
 {
        char            path[MAXPGPATH];
        ListCell   *cell;
@@ -4347,8 +4346,7 @@ XLogFileReadAnyTLI(XLogSegNo segno, int emode, XLogSource source)
 
                if (source == XLOG_FROM_ANY || source == XLOG_FROM_ARCHIVE)
                {
-                       fd = XLogFileRead(segno, emode, tli,
-                                                         XLOG_FROM_ARCHIVE, true);
+                       fd = XLogFileRead(segno, tli, XLOG_FROM_ARCHIVE, true);
                        if (fd != -1)
                        {
                                elog(DEBUG1, "got WAL segment from archive");
@@ -4360,8 +4358,7 @@ XLogFileReadAnyTLI(XLogSegNo segno, int emode, XLogSource source)
 
                if (source == XLOG_FROM_ANY || source == XLOG_FROM_PG_WAL)
                {
-                       fd = XLogFileRead(segno, emode, tli,
-                                                         XLOG_FROM_PG_WAL, true);
+                       fd = XLogFileRead(segno, tli, XLOG_FROM_PG_WAL, true);
                        if (fd != -1)
                        {
                                if (!expectedTLEs)
@@ -4374,7 +4371,7 @@ XLogFileReadAnyTLI(XLogSegNo segno, int emode, XLogSource source)
        /* Couldn't find it.  For simplicity, complain about front timeline */
        XLogFilePath(path, recoveryTargetTLI, segno, wal_segment_size);
        errno = ENOENT;
-       ereport(emode,
+       ereport(DEBUG2,
                        (errcode_for_file_access(),
                         errmsg("could not open file \"%s\": %m", path)));
        return -1;