Generate pgstat_count_slru*() functions for slru using macros

This change replaces seven functions definitions by macros, reducing a
bit some repetitive patterns in the code.  An interesting side effect is
that this removes an inconsistency in the naming of SLRU increment
functions with the field names.

This change is similar to 850f4b4c8cab, 8018ffbf5895 or 83a1a1b56645.

Author: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Discussion: https://postgr.es/m/aLHA//gr4dTpDHHC@ip-10-97-1-34.eu-west-3.compute.internal

2 files changed, 26 insertions, 40 deletions

diff --git a/src/backend/access/transam/slru.c b/src/backend/access/transam/slru.c
index 10ec259f382..ca69ee4d4f4 100644
--- a/src/backend/access/transam/slru.c
+++ b/src/backend/access/transam/slru.c
@@ -408,7 +408,7 @@ SimpleLruZeroPage(SlruCtl ctl, int64 pageno)
 	pg_atomic_write_u64(&shared->latest_page_number, pageno);
 
 	/* update the stats counter of zeroed pages */
-	pgstat_count_slru_page_zeroed(shared->slru_stats_idx);
+	pgstat_count_slru_blocks_zeroed(shared->slru_stats_idx);
 
 	return slotno;
 }
@@ -560,7 +560,7 @@ SimpleLruReadPage(SlruCtl ctl, int64 pageno, bool write_ok,
 			SlruRecentlyUsed(shared, slotno);
 
 			/* update the stats counter of pages found in the SLRU */
-			pgstat_count_slru_page_hit(shared->slru_stats_idx);
+			pgstat_count_slru_blocks_hit(shared->slru_stats_idx);
 
 			return slotno;
 		}
@@ -605,7 +605,7 @@ SimpleLruReadPage(SlruCtl ctl, int64 pageno, bool write_ok,
 		SlruRecentlyUsed(shared, slotno);
 
 		/* update the stats counter of pages not found in SLRU */
-		pgstat_count_slru_page_read(shared->slru_stats_idx);
+		pgstat_count_slru_blocks_read(shared->slru_stats_idx);
 
 		return slotno;
 	}
@@ -648,7 +648,7 @@ SimpleLruReadPage_ReadOnly(SlruCtl ctl, int64 pageno, TransactionId xid)
 			SlruRecentlyUsed(shared, slotno);
 
 			/* update the stats counter of pages found in the SLRU */
-			pgstat_count_slru_page_hit(shared->slru_stats_idx);
+			pgstat_count_slru_blocks_hit(shared->slru_stats_idx);
 
 			return slotno;
 		}
@@ -778,7 +778,7 @@ SimpleLruDoesPhysicalPageExist(SlruCtl ctl, int64 pageno)
 	off_t		endpos;
 
 	/* update the stats counter of checked pages */
-	pgstat_count_slru_page_exists(ctl->shared->slru_stats_idx);
+	pgstat_count_slru_blocks_exists(ctl->shared->slru_stats_idx);
 
 	SlruFileName(ctl, path, segno);
 
@@ -907,7 +907,7 @@ SlruPhysicalWritePage(SlruCtl ctl, int64 pageno, int slotno, SlruWriteAll fdata)
 	int			fd = -1;
 
 	/* update the stats counter of written pages */
-	pgstat_count_slru_page_written(shared->slru_stats_idx);
+	pgstat_count_slru_blocks_written(shared->slru_stats_idx);
 
 	/*
 	 * Honor the write-WAL-before-data rule, if appropriate, so that we do not
diff --git a/src/backend/utils/activity/pgstat_slru.c b/src/backend/utils/activity/pgstat_slru.c
index 7bd8744accb..da50f8a0457 100644
--- a/src/backend/utils/activity/pgstat_slru.c
+++ b/src/backend/utils/activity/pgstat_slru.c
@@ -55,47 +55,33 @@ pgstat_reset_slru(const char *name)
  * SLRU statistics count accumulation functions --- called from slru.c
  */
 
-void
-pgstat_count_slru_page_zeroed(int slru_idx)
-{
-	get_slru_entry(slru_idx)->blocks_zeroed += 1;
+#define PGSTAT_COUNT_SLRU(stat)						\
+void												\
+CppConcat(pgstat_count_slru_,stat)(int slru_idx)	\
+{													\
+	get_slru_entry(slru_idx)->stat += 1;			\
 }
 
-void
-pgstat_count_slru_page_hit(int slru_idx)
-{
-	get_slru_entry(slru_idx)->blocks_hit += 1;
-}
+/* pgstat_count_slru_blocks_zeroed */
+PGSTAT_COUNT_SLRU(blocks_zeroed)
 
-void
-pgstat_count_slru_page_exists(int slru_idx)
-{
-	get_slru_entry(slru_idx)->blocks_exists += 1;
-}
+/* pgstat_count_slru_blocks_hit */
+PGSTAT_COUNT_SLRU(blocks_hit)
 
-void
-pgstat_count_slru_page_read(int slru_idx)
-{
-	get_slru_entry(slru_idx)->blocks_read += 1;
-}
+/* pgstat_count_slru_blocks_exists */
+PGSTAT_COUNT_SLRU(blocks_exists)
 
-void
-pgstat_count_slru_page_written(int slru_idx)
-{
-	get_slru_entry(slru_idx)->blocks_written += 1;
-}
+/* pgstat_count_slru_blocks_read */
+PGSTAT_COUNT_SLRU(blocks_read)
 
-void
-pgstat_count_slru_flush(int slru_idx)
-{
-	get_slru_entry(slru_idx)->flush += 1;
-}
+/* pgstat_count_slru_blocks_written */
+PGSTAT_COUNT_SLRU(blocks_written)
 
-void
-pgstat_count_slru_truncate(int slru_idx)
-{
-	get_slru_entry(slru_idx)->truncate += 1;
-}
+/* pgstat_count_slru_flush */
+PGSTAT_COUNT_SLRU(flush)
+
+/* pgstat_count_slru_truncate */
+PGSTAT_COUNT_SLRU(truncate)
 
 /*
  * Support function for the SQL-callable pgstat* functions. Returns