Provide a DSA area for all parallel queries.

This will allow future parallel query code to dynamically allocate
storage shared by all participants.

Thomas Munro, with assorted changes by me.

3 files changed, 6 insertions, 0 deletions

diff --git a/src/include/executor/execParallel.h b/src/include/executor/execParallel.h
index f4c6d37a119..4bbee691a7f 100644
--- a/src/include/executor/execParallel.h
+++ b/src/include/executor/execParallel.h
@@ -17,6 +17,7 @@
 #include "nodes/execnodes.h"
 #include "nodes/parsenodes.h"
 #include "nodes/plannodes.h"
+#include "utils/dsa.h"
 
 typedef struct SharedExecutorInstrumentation SharedExecutorInstrumentation;
 
@@ -27,6 +28,7 @@ typedef struct ParallelExecutorInfo
 	BufferUsage *buffer_usage;
 	SharedExecutorInstrumentation *instrumentation;
 	shm_mq_handle **tqueue;
+	dsa_area   *area;
 	bool		finished;
 } ParallelExecutorInfo;
 
diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h
index 703604ab9d7..5c3b8683f5b 100644
--- a/src/include/nodes/execnodes.h
+++ b/src/include/nodes/execnodes.h
@@ -427,6 +427,9 @@ typedef struct EState
 	HeapTuple  *es_epqTuple;	/* array of EPQ substitute tuples */
 	bool	   *es_epqTupleSet; /* true if EPQ tuple is provided */
 	bool	   *es_epqScanDone; /* true if EPQ tuple has been fetched */
+
+	/* The per-query shared memory area to use for parallel execution. */
+	struct dsa_area   *es_query_dsa;
 } EState;
 
 
diff --git a/src/include/storage/lwlock.h b/src/include/storage/lwlock.h
index db1c687e21e..3ca4db0a723 100644
--- a/src/include/storage/lwlock.h
+++ b/src/include/storage/lwlock.h
@@ -210,6 +210,7 @@ typedef enum BuiltinTrancheIds
 	LWTRANCHE_BUFFER_MAPPING,
 	LWTRANCHE_LOCK_MANAGER,
 	LWTRANCHE_PREDICATE_LOCK_MANAGER,
+	LWTRANCHE_PARALLEL_QUERY_DSA,
 	LWTRANCHE_FIRST_USER_DEFINED
 }	BuiltinTrancheIds;