Make visibilitymap_set() return previous state of vmbits

It can be useful to know the state of a relation page's VM bits before
visibilitymap_set(). visibilitymap_set() has the old value on hand, so
returning it is simple. This commit does not use visibilitymap_set()'s
new return value.

Author: Melanie Plageman
Reviewed-by: Masahiko Sawada, Andres Freund, Nitin Jadhav, Bilal Yavuz
Discussion: https://postgr.es/m/flat/CAAKRu_ZQe26xdvAqo4weHLR%3DivQ8J4xrSfDDD8uXnh-O-6P6Lg%40mail.gmail.com#6d8d2b4219394f774889509bf3bdc13d,
https://postgr.es/m/ctdjzroezaxmiyah3gwbwm67defsrwj2b5fpfs4ku6msfpxeia%40mwjyqlhwr2wu
This commit is contained in:
Melanie Plageman 2024-12-17 14:13:18 -05:00
parent f020baa066
commit 4b565a198b
2 changed files with 13 additions and 5 deletions

View File

@ -239,8 +239,10 @@ visibilitymap_pin_ok(BlockNumber heapBlk, Buffer vmbuf)
* You must pass a buffer containing the correct map page to this function.
* Call visibilitymap_pin first to pin the right one. This function doesn't do
* any I/O.
*
* Returns the state of the page's VM bits before setting flags.
*/
void
uint8
visibilitymap_set(Relation rel, BlockNumber heapBlk, Buffer heapBuf,
XLogRecPtr recptr, Buffer vmBuf, TransactionId cutoff_xid,
uint8 flags)
@ -250,6 +252,7 @@ visibilitymap_set(Relation rel, BlockNumber heapBlk, Buffer heapBuf,
uint8 mapOffset = HEAPBLK_TO_OFFSET(heapBlk);
Page page;
uint8 *map;
uint8 status;
#ifdef TRACE_VISIBILITYMAP
elog(DEBUG1, "vm_set %s %d", RelationGetRelationName(rel), heapBlk);
@ -274,7 +277,8 @@ visibilitymap_set(Relation rel, BlockNumber heapBlk, Buffer heapBuf,
map = (uint8 *) PageGetContents(page);
LockBuffer(vmBuf, BUFFER_LOCK_EXCLUSIVE);
if (flags != (map[mapByte] >> mapOffset & VISIBILITYMAP_VALID_BITS))
status = (map[mapByte] >> mapOffset) & VISIBILITYMAP_VALID_BITS;
if (flags != status)
{
START_CRIT_SECTION();
@ -311,6 +315,7 @@ visibilitymap_set(Relation rel, BlockNumber heapBlk, Buffer heapBuf,
}
LockBuffer(vmBuf, BUFFER_LOCK_UNLOCK);
return status;
}
/*

View File

@ -31,9 +31,12 @@ extern bool visibilitymap_clear(Relation rel, BlockNumber heapBlk,
extern void visibilitymap_pin(Relation rel, BlockNumber heapBlk,
Buffer *vmbuf);
extern bool visibilitymap_pin_ok(BlockNumber heapBlk, Buffer vmbuf);
extern void visibilitymap_set(Relation rel, BlockNumber heapBlk, Buffer heapBuf,
XLogRecPtr recptr, Buffer vmBuf, TransactionId cutoff_xid,
uint8 flags);
extern uint8 visibilitymap_set(Relation rel,
BlockNumber heapBlk, Buffer heapBuf,
XLogRecPtr recptr,
Buffer vmBuf,
TransactionId cutoff_xid,
uint8 flags);
extern uint8 visibilitymap_get_status(Relation rel, BlockNumber heapBlk, Buffer *vmbuf);
extern void visibilitymap_count(Relation rel, BlockNumber *all_visible, BlockNumber *all_frozen);
extern BlockNumber visibilitymap_prepare_truncate(Relation rel,