1 files changed, 25 insertions, 13 deletions

diff --git a/src/backend/utils/mmgr/dsa.c b/src/backend/utils/mmgr/dsa.c
index 8d1aace40ac..c392a9eabc1 100644
--- a/src/backend/utils/mmgr/dsa.c
+++ b/src/backend/utils/mmgr/dsa.c
@@ -59,6 +59,7 @@
 #include "utils/dsa.h"
 #include "utils/freepage.h"
 #include "utils/memutils.h"
+#include "utils/resowner.h"
 
 /*
  * The size of the initial DSM segment that backs a dsa_area created by
@@ -368,8 +369,13 @@ struct dsa_area
 	/* Pointer to the control object in shared memory. */
 	dsa_area_control *control;
 
-	/* Has the mapping been pinned? */
-	bool		mapping_pinned;
+	/*
+	 * All the mappings are owned by this.  The dsa_area itself is not
+	 * directly tracked by the ResourceOwner, but the effect is the same. NULL
+	 * if the attachment has session lifespan, i.e if dsa_pin_mapping() has
+	 * been called.
+	 */
+	ResourceOwner resowner;
 
 	/*
 	 * This backend's array of segment maps, ordered by segment index
@@ -645,12 +651,14 @@ dsa_pin_mapping(dsa_area *area)
 {
 	int			i;
 
-	Assert(!area->mapping_pinned);
-	area->mapping_pinned = true;
+	if (area->resowner != NULL)
+	{
+		area->resowner = NULL;
 
-	for (i = 0; i <= area->high_segment_index; ++i)
-		if (area->segment_maps[i].segment != NULL)
-			dsm_pin_mapping(area->segment_maps[i].segment);
+		for (i = 0; i <= area->high_segment_index; ++i)
+			if (area->segment_maps[i].segment != NULL)
+				dsm_pin_mapping(area->segment_maps[i].segment);
+	}
 }
 
 /*
@@ -1264,7 +1272,7 @@ create_internal(void *place, size_t size,
 	 */
 	area = palloc(sizeof(dsa_area));
 	area->control = control;
-	area->mapping_pinned = false;
+	area->resowner = CurrentResourceOwner;
 	memset(area->segment_maps, 0, sizeof(dsa_segment_map) * DSA_MAX_SEGMENTS);
 	area->high_segment_index = 0;
 	area->freed_segment_counter = 0;
@@ -1320,7 +1328,7 @@ attach_internal(void *place, dsm_segment *segment, dsa_handle handle)
 	/* Build the backend-local area object. */
 	area = palloc(sizeof(dsa_area));
 	area->control = control;
-	area->mapping_pinned = false;
+	area->resowner = CurrentResourceOwner;
 	memset(&area->segment_maps[0], 0,
 		   sizeof(dsa_segment_map) * DSA_MAX_SEGMENTS);
 	area->high_segment_index = 0;
@@ -1743,6 +1751,7 @@ get_segment_by_index(dsa_area *area, dsa_segment_index index)
 		dsm_handle	handle;
 		dsm_segment *segment;
 		dsa_segment_map *segment_map;
+		ResourceOwner oldowner;
 
 		/*
 		 * If we are reached by dsa_free or dsa_get_address, there must be at
@@ -1761,11 +1770,12 @@ get_segment_by_index(dsa_area *area, dsa_segment_index index)
 			elog(ERROR,
 				 "dsa_area could not attach to a segment that has been freed");
 
+		oldowner = CurrentResourceOwner;
+		CurrentResourceOwner = area->resowner;
 		segment = dsm_attach(handle);
+		CurrentResourceOwner = oldowner;
 		if (segment == NULL)
 			elog(ERROR, "dsa_area could not attach to segment");
-		if (area->mapping_pinned)
-			dsm_pin_mapping(segment);
 		segment_map = &area->segment_maps[index];
 		segment_map->segment = segment;
 		segment_map->mapped_address = dsm_segment_address(segment);
@@ -2067,6 +2077,7 @@ make_new_segment(dsa_area *area, size_t requested_pages)
 	size_t		usable_pages;
 	dsa_segment_map *segment_map;
 	dsm_segment *segment;
+	ResourceOwner oldowner;
 
 	Assert(LWLockHeldByMe(DSA_AREA_LOCK(area)));
 
@@ -2151,12 +2162,13 @@ make_new_segment(dsa_area *area, size_t requested_pages)
 	}
 
 	/* Create the segment. */
+	oldowner = CurrentResourceOwner;
+	CurrentResourceOwner = area->resowner;
 	segment = dsm_create(total_size, 0);
+	CurrentResourceOwner = oldowner;
 	if (segment == NULL)
 		return NULL;
 	dsm_pin_segment(segment);
-	if (area->mapping_pinned)
-		dsm_pin_mapping(segment);
 
 	/* Store the handle in shared memory to be found by index. */
 	area->control->segment_handles[new_index] =