Change pgstat_report_vacuum() to use Relation

This change makes pgstat_report_vacuum() more consistent with
pgstat_report_analyze(), that also uses a Relation.  This enforces a
policy that callers of this routine should open and lock the relation
whose statistics are updated before calling this routine.  We will
unlikely have a lot of callers of this routine in the tree, but it seems
like a good idea to imply this requirement in the long run.

Author: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Suggested-by: Andres Freund <andres@anarazel.de>
Reviewed-by: Chao Li <li.evan.chao@gmail.com>
Discussion: https://postgr.es/m/aUEA6UZZkDCQFgSA@ip-10-97-1-34.eu-west-3.compute.internal

src/backend/access/heap/vacuumlazy.c

@@ -961,8 +961,7 @@ heap_vacuum_rel(Relation rel, const VacuumParams params,
 	 * soon in cases where the failsafe prevented significant amounts of heap
 	 * vacuuming.
 	 */
-	pgstat_report_vacuum(RelationGetRelid(rel),
-						 rel->rd_rel->relisshared,
+	pgstat_report_vacuum(rel,
 						 Max(vacrel->new_live_tuples, 0),
 						 vacrel->recently_dead_tuples +
 						 vacrel->missed_dead_tuples,

src/backend/utils/activity/pgstat_relation.c

@@ -207,14 +207,13 @@ pgstat_drop_relation(Relation rel)
  * Report that the table was just vacuumed and flush IO statistics.
  */
 void
-pgstat_report_vacuum(Oid tableoid, bool shared,
-					 PgStat_Counter livetuples, PgStat_Counter deadtuples,
-					 TimestampTz starttime)
+pgstat_report_vacuum(Relation rel, PgStat_Counter livetuples,
+					 PgStat_Counter deadtuples, TimestampTz starttime)
 {
 	PgStat_EntryRef *entry_ref;
 	PgStatShared_Relation *shtabentry;
 	PgStat_StatTabEntry *tabentry;
-	Oid			dboid = (shared ? InvalidOid : MyDatabaseId);
+	Oid			dboid = (rel->rd_rel->relisshared ? InvalidOid : MyDatabaseId);
 	TimestampTz ts;
 	PgStat_Counter elapsedtime;
 
@@ -226,8 +225,8 @@ pgstat_report_vacuum(Oid tableoid, bool shared,
 	elapsedtime = TimestampDifferenceMilliseconds(starttime, ts);
 
 	/* block acquiring lock for the same reason as pgstat_report_autovac() */
-	entry_ref = pgstat_get_entry_ref_locked(PGSTAT_KIND_RELATION,
-											dboid, tableoid, false);
+	entry_ref = pgstat_get_entry_ref_locked(PGSTAT_KIND_RELATION, dboid,
+											RelationGetRelid(rel), false);
 
 	shtabentry = (PgStatShared_Relation *) entry_ref->shared_stats;
 	tabentry = &shtabentry->stats;

src/include/pgstat.h

@@ -669,8 +669,8 @@ extern void pgstat_init_relation(Relation rel);
 extern void pgstat_assoc_relation(Relation rel);
 extern void pgstat_unlink_relation(Relation rel);
 
-extern void pgstat_report_vacuum(Oid tableoid, bool shared,
-								 PgStat_Counter livetuples, PgStat_Counter deadtuples,
+extern void pgstat_report_vacuum(Relation rel, PgStat_Counter livetuples,
+								 PgStat_Counter deadtuples,
 								 TimestampTz starttime);
 extern void pgstat_report_analyze(Relation rel,
 								  PgStat_Counter livetuples, PgStat_Counter deadtuples,