Bugfix. Detach DSM segment earlier, before cleaning of memory context.

Bugfix. Small mistake during calculation of DSM segment size.

Author: a.pervushina

aqo_shared.c

@@ -50,7 +50,7 @@ get_dsm_all(uint32 *size)
 		seg = dsm_attach(aqo_state->dsm_handler);
 		Assert(seg);
 		dsm_pin_mapping(seg);
-		on_shmem_exit(aqo_detach_shmem, (Datum) &aqo_state->dsm_handler);
+		before_shmem_exit(aqo_detach_shmem, (Datum) &aqo_state->dsm_handler);
 	}
 
 	hdr = (dsm_seg_hdr	*) dsm_segment_address(seg);
@@ -102,7 +102,7 @@ get_cache_address(void)
 			/* Another process created the segment yet. Just attach to. */
 			seg = dsm_attach(aqo_state->dsm_handler);
 			dsm_pin_mapping(seg);
-			on_shmem_exit(aqo_detach_shmem, (Datum) &aqo_state->dsm_handler);
+			before_shmem_exit(aqo_detach_shmem, (Datum) &aqo_state->dsm_handler);
 		}
 
 		hdr = (dsm_seg_hdr	*) dsm_segment_address(seg);
@@ -118,7 +118,7 @@ get_cache_address(void)
 		dsm_pin_mapping(seg);
 		dsm_pin_segment(seg);
 		aqo_state->dsm_handler = dsm_segment_handle(seg);
-		on_shmem_exit(aqo_detach_shmem, (Datum) &aqo_state->dsm_handler);
+		before_shmem_exit(aqo_detach_shmem, (Datum) &aqo_state->dsm_handler);
 
 		hdr = (dsm_seg_hdr *) dsm_segment_address(seg);
 		hdr->magic = AQO_SHARED_MAGIC;
@@ -189,7 +189,6 @@ aqo_init_shmem(void)
 							  HASH_ELEM | HASH_BLOBS);
 
 	LWLockRelease(AddinShmemInitLock);
-
 	LWLockRegisterTranche(aqo_state->lock.tranche, "aqo");
 }
 

learn_cache.c

@@ -252,9 +252,11 @@ init_with_dsm(OkNNrdata *data, dsm_block_hdr *hdr, List **relnames)
 			*relnames = lappend(*relnames, s);
 			ptr += len;
 		}
+		return calculate_size(hdr->cols, *relnames);
 	}
 
-	return calculate_size(hdr->cols, *relnames);
+	/* It is just read operation. No any interest in size calculation. */
+	return 0;
 }
 
 void
@@ -275,10 +277,11 @@ lc_flush_data(void)
 	{
 		dsm_block_hdr  *hdr = (dsm_block_hdr *) ptr;
 		OkNNrdata		data;
-		List		   *relnames;
+		List		   *relnames = NIL;
 		uint32			delta = 0;
 
 		delta = init_with_dsm(&data, hdr, &relnames);
+		Assert(delta > 0);
 		ptr += delta;
 		size -= delta;
 		update_fss(hdr->key.fs, hdr->key.fss, &data, relnames);