From: Alvaro Herrera Date: Fri, 8 May 2020 16:40:24 -0400 Subject: [PATCH 1/2] fix WALRead API to take seg/segcxt from XLogReaderState --- src/backend/access/transam/xlogreader.c | 31 +++++++++++-------------- src/backend/access/transam/xlogutils.c | 1 - src/backend/replication/walsender.c | 6 ++--- src/bin/pg_waldump/pg_waldump.c | 1 - src/include/access/xlogreader.h | 4 +--- 5 files changed, 17 insertions(+), 26 deletions(-) diff --git a/src/backend/access/transam/xlogreader.c b/src/backend/access/transam/xlogreader.c index 7cee8b92c9..f42dee2640 100644 --- a/src/backend/access/transam/xlogreader.c +++ b/src/backend/access/transam/xlogreader.c @@ -1050,8 +1050,6 @@ err: * Read 'count' bytes into 'buf', starting at location 'startptr', from WAL * fetched from timeline 'tli'. * - * 'seg/segcxt' identify the last segment used. - * * Returns true if succeeded, false if an error occurs, in which case * 'errinfo' receives error details. * @@ -1061,7 +1059,6 @@ err: bool WALRead(XLogReaderState *state, char *buf, XLogRecPtr startptr, Size count, TimeLineID tli, - WALOpenSegment *seg, WALSegmentContext *segcxt, WALReadError *errinfo) { char *p; @@ -1078,34 +1075,34 @@ WALRead(XLogReaderState *state, int segbytes; int readbytes; - startoff = XLogSegmentOffset(recptr, segcxt->ws_segsize); + startoff = XLogSegmentOffset(recptr, state->segcxt.ws_segsize); /* * If the data we want is not in a segment we have open, close what we * have (if anything) and open the next one, using the caller's * provided openSegment callback. */ - if (seg->ws_file < 0 || - !XLByteInSeg(recptr, seg->ws_segno, segcxt->ws_segsize) || - tli != seg->ws_tli) + if (state->seg.ws_file < 0 || + !XLByteInSeg(recptr, state->seg.ws_segno, state->segcxt.ws_segsize) || + tli != state->seg.ws_tli) { XLogSegNo nextSegNo; - if (seg->ws_file >= 0) + if (state->seg.ws_file >= 0) state->routine.segment_close(state); - XLByteToSeg(recptr, nextSegNo, segcxt->ws_segsize); - seg->ws_file = state->routine.segment_open(state, nextSegNo, - segcxt, &tli); + XLByteToSeg(recptr, nextSegNo, state->segcxt.ws_segsize); + state->seg.ws_file = state->routine.segment_open(state, nextSegNo, + &state->segcxt, &tli); /* Update the current segment info. */ - seg->ws_tli = tli; - seg->ws_segno = nextSegNo; + state->seg.ws_tli = tli; + state->seg.ws_segno = nextSegNo; } /* How many bytes are within this segment? */ - if (nbytes > (segcxt->ws_segsize - startoff)) - segbytes = segcxt->ws_segsize - startoff; + if (nbytes > (state->segcxt.ws_segsize - startoff)) + segbytes = state->segcxt.ws_segsize - startoff; else segbytes = nbytes; @@ -1115,7 +1112,7 @@ WALRead(XLogReaderState *state, /* Reset errno first; eases reporting non-errno-affecting errors */ errno = 0; - readbytes = pg_pread(seg->ws_file, p, segbytes, (off_t) startoff); + readbytes = pg_pread(state->seg.ws_file, p, segbytes, (off_t) startoff); #ifndef FRONTEND pgstat_report_wait_end(); @@ -1127,7 +1124,7 @@ WALRead(XLogReaderState *state, errinfo->wre_req = segbytes; errinfo->wre_read = readbytes; errinfo->wre_off = startoff; - errinfo->wre_seg = *seg; + errinfo->wre_seg = state->seg; return false; } diff --git a/src/backend/access/transam/xlogutils.c b/src/backend/access/transam/xlogutils.c index bbd801513a..fc0bb7d059 100644 --- a/src/backend/access/transam/xlogutils.c +++ b/src/backend/access/transam/xlogutils.c @@ -947,7 +947,6 @@ read_local_xlog_page(XLogReaderState *state, XLogRecPtr targetPagePtr, * zero-padded up to the page boundary if it's incomplete. */ if (!WALRead(state, cur_page, targetPagePtr, XLOG_BLCKSZ, tli, - &state->seg, &state->segcxt, &errinfo)) WALReadRaiseError(&errinfo); diff --git a/src/backend/replication/walsender.c b/src/backend/replication/walsender.c index d18475b854..ed8c08cb6a 100644 --- a/src/backend/replication/walsender.c +++ b/src/backend/replication/walsender.c @@ -840,8 +840,6 @@ logical_read_xlog_page(XLogReaderState *state, XLogRecPtr targetPagePtr, int req sendSeg->ws_tli, /* Pass the current TLI because only * WalSndSegmentOpen controls whether new * TLI is needed. */ - sendSeg, - sendCxt, &errinfo)) WALReadRaiseError(&errinfo); @@ -2760,6 +2758,8 @@ XLogSendPhysical(void) enlargeStringInfo(&output_message, nbytes); retry: + fake_xlogreader.seg = *sendSeg; + fake_xlogreader.segcxt = *sendCxt; if (!WALRead(&fake_xlogreader, &output_message.data[output_message.len], startptr, @@ -2767,8 +2767,6 @@ retry: sendSeg->ws_tli, /* Pass the current TLI because only * WalSndSegmentOpen controls whether new * TLI is needed. */ - sendSeg, - sendCxt, &errinfo)) WALReadRaiseError(&errinfo); diff --git a/src/bin/pg_waldump/pg_waldump.c b/src/bin/pg_waldump/pg_waldump.c index e29f65500f..46734914b7 100644 --- a/src/bin/pg_waldump/pg_waldump.c +++ b/src/bin/pg_waldump/pg_waldump.c @@ -356,7 +356,6 @@ WALDumpReadPage(XLogReaderState *state, XLogRecPtr targetPagePtr, int reqLen, } if (!WALRead(state, readBuff, targetPagePtr, count, private->timeline, - &state->seg, &state->segcxt, &errinfo)) { WALOpenSegment *seg = &errinfo.wre_seg; diff --git a/src/include/access/xlogreader.h b/src/include/access/xlogreader.h index 81af200f5e..e77f478d68 100644 --- a/src/include/access/xlogreader.h +++ b/src/include/access/xlogreader.h @@ -301,9 +301,7 @@ typedef struct WALReadError extern bool WALRead(XLogReaderState *state, char *buf, XLogRecPtr startptr, Size count, - TimeLineID tli, WALOpenSegment *seg, - WALSegmentContext *segcxt, - WALReadError *errinfo); + TimeLineID tli, WALReadError *errinfo); /* Functions for decoding an XLogRecord */ -- 2.20.1 --/04w6evG8XlLl3ft Content-Type: text/x-diff; charset=us-ascii Content-Disposition: attachment; filename="0002-Simplify-XLogReader-s-open_segment-API.patch"