PartitionFilter: invalidate PartRelationInfo on partition creation, fix invalidate_pathman_relation_info()

funbringer · funbringer · commit 79466c6d6c24 · 2016-08-10T17:33:16.000+03:00
diff --git a/src/hooks.c b/src/hooks.c
@@ -452,6 +452,10 @@ pathman_post_parse_analysis_hook(ParseState *pstate, Query *query)
 	if (post_parse_analyze_hook_next)
 		post_parse_analyze_hook_next(pstate, query);
 
+	/* Finish delayed invalidation jobs */
+	if (IsPathmanReady())
+		finish_delayed_invalidation();
+
 	/* Load config if pg_pathman exists & it's still necessary */
 	if (IsPathmanEnabled() &&
 		initialization_needed &&
@@ -461,10 +465,6 @@ pathman_post_parse_analysis_hook(ParseState *pstate, Query *query)
 		load_config(); /* perform main cache initialization */
 	}
 
-	/* Finish delayed invalidation jobs */
-	if (IsPathmanReady())
-		finish_delayed_invalidation();
-
 	inheritance_disabled_relids = NIL;
 	inheritance_enabled_relids = NIL;
 }
@@ -495,6 +495,9 @@ pathman_relcache_hook(Datum arg, Oid relid)
 	PartParentSearch	search;
 	Oid					partitioned_table;
 
+	if (!IsPathmanReady())
+		return;
+
 	/* Invalidate PartParentInfo cache if needed */
 	partitioned_table = forget_parent_of_partition(relid, &search);
 
@@ -516,6 +519,9 @@ pathman_relcache_hook(Datum arg, Oid relid)
 			{
 				elog(DEBUG2, "Invalidation message for relation %u [%u]",
 					 relid, MyProcPid);
+
+				if (relid == get_pathman_config_relid())
+					delay_pathman_shutdown();
 			}
 			break;
 
diff --git a/src/init.c b/src/init.c
@@ -78,8 +78,11 @@ static int oid_cmp(const void *p1, const void *p2);
  * Create local PartRelationInfo cache & load pg_pathman's config.
  */
 void
-load_config()
+load_config(void)
 {
+	/* cache PATHMAN_CONFIG relation Oid */
+	pathman_config_relid = get_relname_relid(PATHMAN_CONFIG, get_pathman_schema());
+
 	init_local_config();	/* create 'relations' hash table */
 	read_pathman_config();	/* read PATHMAN_CONFIG table & fill cache */
 
@@ -88,6 +91,34 @@ load_config()
 	elog(DEBUG2, "pg_pathman's config has been loaded successfully");
 }
 
+/*
+ * Destroy local caches & free memory.
+ */
+void
+unload_config(void)
+{
+	HASH_SEQ_STATUS		status;
+	PartRelationInfo   *prel;
+
+	hash_seq_init(&status, partitioned_rels);
+	while((prel = (PartRelationInfo *) hash_seq_search(&status)) != NULL)
+	{
+		if (PrelIsValid(prel))
+		{
+			FreeChildrenArray(prel);
+			FreeRangesArray(prel);
+		}
+	}
+
+	/* Now we can safely destroy hash tables */
+	hash_destroy(partitioned_rels);
+	hash_destroy(parent_cache);
+	partitioned_rels = NULL;
+	parent_cache = NULL;
+
+	initialization_needed = true;
+}
+
 /*
  * Estimate shmem amount needed for pg_pathman to run.
  */
@@ -105,12 +136,6 @@ init_local_config(void)
 {
 	HASHCTL ctl;
 
-	if (partitioned_rels)
-	{
-		elog(DEBUG2, "pg_pathman's partitioned relations table already exists");
-		return;
-	}
-
 	memset(&ctl, 0, sizeof(ctl));
 	ctl.keysize = sizeof(Oid);
 	ctl.entrysize = sizeof(PartRelationInfo);
@@ -392,24 +417,20 @@ bool
 pathman_config_contains_relation(Oid relid, Datum *values, bool *isnull,
 								 TransactionId *xmin)
 {
-	Oid				pathman_config;
 	Relation		rel;
 	HeapScanDesc	scan;
 	ScanKeyData		key[1];
 	Snapshot		snapshot;
 	HeapTuple		htup;
 	bool			contains_rel = false;
 
-	/* Get PATHMAN_CONFIG table Oid */
-	pathman_config = get_relname_relid(PATHMAN_CONFIG, get_pathman_schema());
-
 	ScanKeyInit(&key[0],
 				Anum_pathman_config_partrel,
 				BTEqualStrategyNumber, F_OIDEQ,
 				ObjectIdGetDatum(relid));
 
-	/* Open relation with latest snapshot available */
-	rel = heap_open(pathman_config, AccessShareLock);
+	/* Open PATHMAN_CONFIG with latest snapshot available */
+	rel = heap_open(get_pathman_config_relid(), AccessShareLock);
 
 	/* Check that 'partrel' column is if regclass type */
 	Assert(RelationGetDescr(rel)->
@@ -471,17 +492,13 @@ pathman_config_contains_relation(Oid relid, Datum *values, bool *isnull,
 static void
 read_pathman_config(void)
 {
-	Oid				pathman_config;
 	Relation		rel;
 	HeapScanDesc	scan;
 	Snapshot		snapshot;
 	HeapTuple		htup;
 
-	/* Get PATHMAN_CONFIG table Oid */
-	pathman_config = get_relname_relid(PATHMAN_CONFIG, get_pathman_schema());
-
-	/* Open relation with latest snapshot available */
-	rel = heap_open(pathman_config, AccessShareLock);
+	/* Open PATHMAN_CONFIG with latest snapshot available */
+	rel = heap_open(get_pathman_config_relid(), AccessShareLock);
 
 	/* Check that 'partrel' column is if regclass type */
 	Assert(RelationGetDescr(rel)->
diff --git a/src/init.h b/src/init.h
@@ -28,6 +28,7 @@ Size estimate_pathman_shmem_size(void);
 void init_local_config(void);
 void init_shmem_config(void);
 void load_config(void);
+void unload_config(void);
 
 void fill_prel_with_partitions(const Oid *partitions,
 							   const uint32 parts_count,
diff --git a/src/partition_filter.c b/src/partition_filter.c
@@ -207,6 +207,9 @@ partition_filter_exec(CustomScanState *node)
 			selected_partid = create_partitions(state->partitioned_table,
 												state->temp_const.constvalue,
 												state->temp_const.consttype);
+
+			/* get_pathman_relation_info() will refresh this entry */
+			invalidate_pathman_relation_info(state->partitioned_table, NULL);
 		}
 		else
 			selected_partid = parts[0];
diff --git a/src/pathman.h b/src/pathman.h
@@ -56,6 +56,10 @@
 /* type modifier (typmod) for 'range_interval' */
 #define PATHMAN_CONFIG_interval_typmod		-1
 
+extern Oid	pathman_config_relid;
+
+Oid get_pathman_config_relid(void);
+
 
 /*
  * pg_pathman's global state.
diff --git a/src/pg_pathman.c b/src/pg_pathman.c
@@ -50,6 +50,7 @@ List		   *inheritance_disabled_relids = NIL;
 List		   *inheritance_enabled_relids = NIL;
 bool			pg_pathman_enable = true;
 PathmanState   *pmstate;
+Oid				pathman_config_relid = InvalidOid;
 
 
 /* pg module functions */
@@ -2075,3 +2076,9 @@ generate_mergeappend_paths(PlannerInfo *root, RelOptInfo *rel,
 		}
 	}
 }
+
+Oid
+get_pathman_config_relid(void)
+{
+	return pathman_config_relid;
+}
diff --git a/src/relation_info.c b/src/relation_info.c
@@ -26,8 +26,9 @@
 #include "utils/snapmgr.h"
 
 
-static List *delayed_invalidation_parent_rels = NIL;
-static List *delayed_invalidation_vague_rels = NIL;
+static List	   *delayed_invalidation_parent_rels = NIL;
+static List	   *delayed_invalidation_vague_rels = NIL;
+static bool		delayed_shutdown = false;
 
 /* Add unique Oid to list, allocate in TopMemoryContext */
 #define list_add_unique(list, oid) \
@@ -51,60 +52,6 @@ static Oid get_parent_of_partition_internal(Oid partition,
 static bool perform_parent_refresh(Oid parent);
 
 
-/*
- * Useful static functions for freeing memory.
- */
-
-static inline void
-FreeChildrenArray(PartRelationInfo *prel)
-{
-	uint32	i;
-
-	Assert(PrelIsValid(prel));
-
-	/* Remove relevant PartParentInfos */
-	if ((prel)->children)
-	{
-		for (i = 0; i < PrelChildrenCount(prel); i++)
-		{
-			Oid child = (prel)->children[i];
-
-			/* If it's *always been* relid's partition, free cache */
-			if (prel->key == get_parent_of_partition(child, NULL))
-				forget_parent_of_partition(child, NULL);
-		}
-
-		pfree((prel)->children);
-		(prel)->children = NULL;
-	}
-}
-
-static inline void
-FreeRangesArray(PartRelationInfo *prel)
-{
-	uint32	i;
-
-	Assert(PrelIsValid(prel));
-
-	/* Remove RangeEntries array */
-	if ((prel)->ranges)
-	{
-		/* Remove persistent entries if not byVal */
-		if (!(prel)->attbyval)
-		{
-			for (i = 0; i < PrelChildrenCount(prel); i++)
-			{
-				pfree(DatumGetPointer((prel)->ranges[i].min));
-				pfree(DatumGetPointer((prel)->ranges[i].max));
-			}
-		}
-
-		pfree((prel)->ranges);
-		(prel)->ranges = NULL;
-	}
-}
-
-
 /*
  * refresh\invalidate\get\remove PartRelationInfo functions.
  */
@@ -132,6 +79,12 @@ refresh_pathman_relation_info(Oid relid,
 			 "Creating new record for relation %u in pg_pathman's cache [%u]",
 		 relid, MyProcPid);
 
+	/*
+	 * NOTE: Trick clang analyzer (first access without NULL pointer check).
+	 * Access to field 'valid' results in a dereference of a null pointer.
+	 */
+	prel->cmp_proc = InvalidOid;
+
 	/* Clear outdated resources */
 	if (found && PrelIsValid(prel))
 	{
@@ -199,24 +152,33 @@ refresh_pathman_relation_info(Oid relid,
 void
 invalidate_pathman_relation_info(Oid relid, bool *found)
 {
-	PartRelationInfo   *prel = hash_search(partitioned_rels,
-										   (const void *) &relid,
-										   (found ? HASH_FIND : HASH_ENTER),
-										   found);
+	bool				prel_found;
+	HASHACTION			action = found ? HASH_FIND : HASH_ENTER;
+	PartRelationInfo   *prel;
 
-	if(found && PrelIsValid(prel))
+	prel = hash_search(partitioned_rels,
+					   (const void *) &relid,
+					   action, &prel_found);
+
+	if ((action == HASH_FIND ||
+		(action == HASH_ENTER && prel_found)) && PrelIsValid(prel))
 	{
 		FreeChildrenArray(prel);
 		FreeRangesArray(prel);
+
+		prel->valid = false; /* now cache entry is invalid */
 	}
-	/* not found => we create a new one */
-	else if (!found)
+	/* Handle invalid PartRelationInfo */
+	else if (prel)
 	{
 		prel->children = NULL;
 		prel->ranges = NULL;
+
+		prel->valid = false; /* now cache entry is invalid */
 	}
 
-	prel->valid = false; /* now cache entry is invalid */
+	/* Set 'found' if necessary */
+	if (found) *found = prel_found;
 
 	elog(DEBUG2,
 		 "Invalidating record for relation %u in pg_pathman's cache [%u]",
@@ -291,6 +253,13 @@ remove_pathman_relation_info(Oid relid)
  * Functions for delayed invalidation.
  */
 
+/* Add new delayed pathman shutdown job (DROP EXTENSION) */
+void
+delay_pathman_shutdown(void)
+{
+	delayed_shutdown = true;
+}
+
 /* Add new delayed invalidation job for a [ex-]parent relation */
 void
 delay_invalidation_parent_rel(Oid parent)
@@ -311,17 +280,23 @@ finish_delayed_invalidation(void)
 {
 	/* Exit early if there's nothing to do */
 	if (delayed_invalidation_parent_rels == NIL &&
-		delayed_invalidation_vague_rels == NIL)
+		delayed_invalidation_vague_rels == NIL &&
+		delayed_shutdown == false)
 	{
 		return;
 	}
 
 	/* Check that current state is transactional */
 	if (IsTransactionState())
 	{
-		ListCell *lc;
+		ListCell   *lc;
 
-		//elog(WARNING, "invalidating...");
+		if (delayed_shutdown)
+		{
+			delayed_shutdown = false;
+			unload_config();
+			return;
+		}
 
 		/* Process relations that are (or were) definitely partitioned */
 		foreach (lc, delayed_invalidation_parent_rels)
@@ -541,8 +516,7 @@ perform_parent_refresh(Oid parent)
 		parttype = DatumGetPartType(values[Anum_pathman_config_parttype - 1]);
 		attname = DatumGetTextP(values[Anum_pathman_config_attname - 1]);
 
-		if (!refresh_pathman_relation_info(parent, parttype,
-										   text_to_cstring(attname)))
+		if (!refresh_pathman_relation_info(parent, parttype, text_to_cstring(attname)))
 			return false;
 	}
 	else
diff --git a/src/relation_info.h b/src/relation_info.h

Original file line number	Diff line number	Diff line change
`@@ -50,6 +50,7 @@ List *inheritance_disabled_relids = NIL;`
`50`	`50`	`List *inheritance_enabled_relids = NIL;`
`51`	`51`	`bool pg_pathman_enable = true;`
`52`	`52`	`PathmanState *pmstate;`
	`53`	`+Oid pathman_config_relid = InvalidOid;`
`53`	`54`
`54`	`55`
`55`	`56`	`/* pg module functions */`
`@@ -2075,3 +2076,9 @@ generate_mergeappend_paths(PlannerInfo root, RelOptInfo rel,`
`2075`	`2076`	`}`
`2076`	`2077`	`}`
`2077`	`2078`	`}`
	`2079`	`+`
	`2080`	`+Oid`
	`2081`	`+get_pathman_config_relid(void)`
	`2082`	`+{`
	`2083`	`+ return pathman_config_relid;`
	`2084`	`+}`