Line data Source code
1 : /*-------------------------------------------------------------------------
2 : *
3 : * plancache.c
4 : * Plan cache management.
5 : *
6 : * The plan cache manager has two principal responsibilities: deciding when
7 : * to use a generic plan versus a custom (parameter-value-specific) plan,
8 : * and tracking whether cached plans need to be invalidated because of schema
9 : * changes in the objects they depend on.
10 : *
11 : * The logic for choosing generic or custom plans is in choose_custom_plan,
12 : * which see for comments.
13 : *
14 : * Cache invalidation is driven off sinval events. Any CachedPlanSource
15 : * that matches the event is marked invalid, as is its generic CachedPlan
16 : * if it has one. When (and if) the next demand for a cached plan occurs,
17 : * parse analysis and rewrite is repeated to build a new valid query tree,
18 : * and then planning is performed as normal. We also force re-analysis and
19 : * re-planning if the active search_path is different from the previous time
20 : * or, if RLS is involved, if the user changes or the RLS environment changes.
21 : *
22 : * Note that if the sinval was a result of user DDL actions, parse analysis
23 : * could throw an error, for example if a column referenced by the query is
24 : * no longer present. Another possibility is for the query's output tupdesc
25 : * to change (for instance "SELECT *" might expand differently than before).
26 : * The creator of a cached plan can specify whether it is allowable for the
27 : * query to change output tupdesc on replan --- if so, it's up to the
28 : * caller to notice changes and cope with them.
29 : *
30 : * Currently, we track exactly the dependencies of plans on relations,
31 : * user-defined functions, and domains. On relcache invalidation events or
32 : * pg_proc or pg_type syscache invalidation events, we invalidate just those
33 : * plans that depend on the particular object being modified. (Note: this
34 : * scheme assumes that any table modification that requires replanning will
35 : * generate a relcache inval event.) We also watch for inval events on
36 : * certain other system catalogs, such as pg_namespace; but for them, our
37 : * response is just to invalidate all plans. We expect updates on those
38 : * catalogs to be infrequent enough that more-detailed tracking is not worth
39 : * the effort.
40 : *
41 : * In addition to full-fledged query plans, we provide a facility for
42 : * detecting invalidations of simple scalar expressions. This is fairly
43 : * bare-bones; it's the caller's responsibility to build a new expression
44 : * if the old one gets invalidated.
45 : *
46 : *
47 : * Portions Copyright (c) 1996-2019, PostgreSQL Global Development Group
48 : * Portions Copyright (c) 1994, Regents of the University of California
49 : *
50 : * IDENTIFICATION
51 : * src/backend/utils/cache/plancache.c
52 : *
53 : *-------------------------------------------------------------------------
54 : */
55 : #include "postgres.h"
56 :
57 : #include <limits.h>
58 :
59 : #include "access/transam.h"
60 : #include "catalog/namespace.h"
61 : #include "executor/executor.h"
62 : #include "miscadmin.h"
63 : #include "nodes/nodeFuncs.h"
64 : #include "optimizer/optimizer.h"
65 : #include "parser/analyze.h"
66 : #include "parser/parsetree.h"
67 : #include "storage/lmgr.h"
68 : #include "tcop/pquery.h"
69 : #include "tcop/utility.h"
70 : #include "utils/inval.h"
71 : #include "utils/memutils.h"
72 : #include "utils/resowner_private.h"
73 : #include "utils/rls.h"
74 : #include "utils/snapmgr.h"
75 : #include "utils/syscache.h"
76 :
77 :
78 : /*
79 : * We must skip "overhead" operations that involve database access when the
80 : * cached plan's subject statement is a transaction control command.
81 : */
82 : #define IsTransactionStmtPlan(plansource) \
83 : ((plansource)->raw_parse_tree && \
84 : IsA((plansource)->raw_parse_tree->stmt, TransactionStmt))
85 :
86 : /*
87 : * This is the head of the backend's list of "saved" CachedPlanSources (i.e.,
88 : * those that are in long-lived storage and are examined for sinval events).
89 : * We use a dlist instead of separate List cells so that we can guarantee
90 : * to save a CachedPlanSource without error.
91 : */
92 : static dlist_head saved_plan_list = DLIST_STATIC_INIT(saved_plan_list);
93 :
94 : /*
95 : * This is the head of the backend's list of CachedExpressions.
96 : */
97 : static dlist_head cached_expression_list = DLIST_STATIC_INIT(cached_expression_list);
98 :
99 : static void ReleaseGenericPlan(CachedPlanSource *plansource);
100 : static List *RevalidateCachedQuery(CachedPlanSource *plansource,
101 : QueryEnvironment *queryEnv);
102 : static bool CheckCachedPlan(CachedPlanSource *plansource);
103 : static CachedPlan *BuildCachedPlan(CachedPlanSource *plansource, List *qlist,
104 : ParamListInfo boundParams, QueryEnvironment *queryEnv);
105 : static bool choose_custom_plan(CachedPlanSource *plansource,
106 : ParamListInfo boundParams);
107 : static double cached_plan_cost(CachedPlan *plan, bool include_planner);
108 : static Query *QueryListGetPrimaryStmt(List *stmts);
109 : static void AcquireExecutorLocks(List *stmt_list, bool acquire);
110 : static void AcquirePlannerLocks(List *stmt_list, bool acquire);
111 : static void ScanQueryForLocks(Query *parsetree, bool acquire);
112 : static bool ScanQueryWalker(Node *node, bool *acquire);
113 : static TupleDesc PlanCacheComputeResultDesc(List *stmt_list);
114 : static void PlanCacheRelCallback(Datum arg, Oid relid);
115 : static void PlanCacheObjectCallback(Datum arg, int cacheid, uint32 hashvalue);
116 : static void PlanCacheSysCallback(Datum arg, int cacheid, uint32 hashvalue);
117 :
118 : /* GUC parameter */
119 : int plan_cache_mode;
120 :
121 : /*
122 : * InitPlanCache: initialize module during InitPostgres.
123 : *
124 : * All we need to do is hook into inval.c's callback lists.
125 : */
126 : void
127 9882 : InitPlanCache(void)
128 : {
129 9882 : CacheRegisterRelcacheCallback(PlanCacheRelCallback, (Datum) 0);
130 9882 : CacheRegisterSyscacheCallback(PROCOID, PlanCacheObjectCallback, (Datum) 0);
131 9882 : CacheRegisterSyscacheCallback(TYPEOID, PlanCacheObjectCallback, (Datum) 0);
132 9882 : CacheRegisterSyscacheCallback(NAMESPACEOID, PlanCacheSysCallback, (Datum) 0);
133 9882 : CacheRegisterSyscacheCallback(OPEROID, PlanCacheSysCallback, (Datum) 0);
134 9882 : CacheRegisterSyscacheCallback(AMOPOPID, PlanCacheSysCallback, (Datum) 0);
135 9882 : CacheRegisterSyscacheCallback(FOREIGNSERVEROID, PlanCacheSysCallback, (Datum) 0);
136 9882 : CacheRegisterSyscacheCallback(FOREIGNDATAWRAPPEROID, PlanCacheSysCallback, (Datum) 0);
137 9882 : }
138 :
139 : /*
140 : * CreateCachedPlan: initially create a plan cache entry.
141 : *
142 : * Creation of a cached plan is divided into two steps, CreateCachedPlan and
143 : * CompleteCachedPlan. CreateCachedPlan should be called after running the
144 : * query through raw_parser, but before doing parse analysis and rewrite;
145 : * CompleteCachedPlan is called after that. The reason for this arrangement
146 : * is that it can save one round of copying of the raw parse tree, since
147 : * the parser will normally scribble on the raw parse tree. Callers would
148 : * otherwise need to make an extra copy of the parse tree to ensure they
149 : * still had a clean copy to present at plan cache creation time.
150 : *
151 : * All arguments presented to CreateCachedPlan are copied into a memory
152 : * context created as a child of the call-time CurrentMemoryContext, which
153 : * should be a reasonably short-lived working context that will go away in
154 : * event of an error. This ensures that the cached plan data structure will
155 : * likewise disappear if an error occurs before we have fully constructed it.
156 : * Once constructed, the cached plan can be made longer-lived, if needed,
157 : * by calling SaveCachedPlan.
158 : *
159 : * raw_parse_tree: output of raw_parser(), or NULL if empty query
160 : * query_string: original query text
161 : * commandTag: compile-time-constant tag for query, or NULL if empty query
162 : */
163 : CachedPlanSource *
164 24652 : CreateCachedPlan(RawStmt *raw_parse_tree,
165 : const char *query_string,
166 : const char *commandTag)
167 : {
168 : CachedPlanSource *plansource;
169 : MemoryContext source_context;
170 : MemoryContext oldcxt;
171 :
172 : Assert(query_string != NULL); /* required as of 8.4 */
173 :
174 : /*
175 : * Make a dedicated memory context for the CachedPlanSource and its
176 : * permanent subsidiary data. It's probably not going to be large, but
177 : * just in case, allow it to grow large. Initially it's a child of the
178 : * caller's context (which we assume to be transient), so that it will be
179 : * cleaned up on error.
180 : */
181 24652 : source_context = AllocSetContextCreate(CurrentMemoryContext,
182 : "CachedPlanSource",
183 : ALLOCSET_START_SMALL_SIZES);
184 :
185 : /*
186 : * Create and fill the CachedPlanSource struct within the new context.
187 : * Most fields are just left empty for the moment.
188 : */
189 24652 : oldcxt = MemoryContextSwitchTo(source_context);
190 :
191 24652 : plansource = (CachedPlanSource *) palloc0(sizeof(CachedPlanSource));
192 24652 : plansource->magic = CACHEDPLANSOURCE_MAGIC;
193 24652 : plansource->raw_parse_tree = copyObject(raw_parse_tree);
194 24652 : plansource->query_string = pstrdup(query_string);
195 24652 : MemoryContextSetIdentifier(source_context, plansource->query_string);
196 24652 : plansource->commandTag = commandTag;
197 24652 : plansource->param_types = NULL;
198 24652 : plansource->num_params = 0;
199 24652 : plansource->parserSetup = NULL;
200 24652 : plansource->parserSetupArg = NULL;
201 24652 : plansource->cursor_options = 0;
202 24652 : plansource->fixed_result = false;
203 24652 : plansource->resultDesc = NULL;
204 24652 : plansource->context = source_context;
205 24652 : plansource->query_list = NIL;
206 24652 : plansource->relationOids = NIL;
207 24652 : plansource->invalItems = NIL;
208 24652 : plansource->search_path = NULL;
209 24652 : plansource->query_context = NULL;
210 24652 : plansource->rewriteRoleId = InvalidOid;
211 24652 : plansource->rewriteRowSecurity = false;
212 24652 : plansource->dependsOnRLS = false;
213 24652 : plansource->gplan = NULL;
214 24652 : plansource->is_oneshot = false;
215 24652 : plansource->is_complete = false;
216 24652 : plansource->is_saved = false;
217 24652 : plansource->is_valid = false;
218 24652 : plansource->generation = 0;
219 24652 : plansource->generic_cost = -1;
220 24652 : plansource->total_custom_cost = 0;
221 24652 : plansource->num_custom_plans = 0;
222 :
223 24652 : MemoryContextSwitchTo(oldcxt);
224 :
225 24652 : return plansource;
226 : }
227 :
228 : /*
229 : * CreateOneShotCachedPlan: initially create a one-shot plan cache entry.
230 : *
231 : * This variant of CreateCachedPlan creates a plan cache entry that is meant
232 : * to be used only once. No data copying occurs: all data structures remain
233 : * in the caller's memory context (which typically should get cleared after
234 : * completing execution). The CachedPlanSource struct itself is also created
235 : * in that context.
236 : *
237 : * A one-shot plan cannot be saved or copied, since we make no effort to
238 : * preserve the raw parse tree unmodified. There is also no support for
239 : * invalidation, so plan use must be completed in the current transaction,
240 : * and DDL that might invalidate the querytree_list must be avoided as well.
241 : *
242 : * raw_parse_tree: output of raw_parser(), or NULL if empty query
243 : * query_string: original query text
244 : * commandTag: compile-time-constant tag for query, or NULL if empty query
245 : */
246 : CachedPlanSource *
247 7468 : CreateOneShotCachedPlan(RawStmt *raw_parse_tree,
248 : const char *query_string,
249 : const char *commandTag)
250 : {
251 : CachedPlanSource *plansource;
252 :
253 : Assert(query_string != NULL); /* required as of 8.4 */
254 :
255 : /*
256 : * Create and fill the CachedPlanSource struct within the caller's memory
257 : * context. Most fields are just left empty for the moment.
258 : */
259 7468 : plansource = (CachedPlanSource *) palloc0(sizeof(CachedPlanSource));
260 7468 : plansource->magic = CACHEDPLANSOURCE_MAGIC;
261 7468 : plansource->raw_parse_tree = raw_parse_tree;
262 7468 : plansource->query_string = query_string;
263 7468 : plansource->commandTag = commandTag;
264 7468 : plansource->param_types = NULL;
265 7468 : plansource->num_params = 0;
266 7468 : plansource->parserSetup = NULL;
267 7468 : plansource->parserSetupArg = NULL;
268 7468 : plansource->cursor_options = 0;
269 7468 : plansource->fixed_result = false;
270 7468 : plansource->resultDesc = NULL;
271 7468 : plansource->context = CurrentMemoryContext;
272 7468 : plansource->query_list = NIL;
273 7468 : plansource->relationOids = NIL;
274 7468 : plansource->invalItems = NIL;
275 7468 : plansource->search_path = NULL;
276 7468 : plansource->query_context = NULL;
277 7468 : plansource->rewriteRoleId = InvalidOid;
278 7468 : plansource->rewriteRowSecurity = false;
279 7468 : plansource->dependsOnRLS = false;
280 7468 : plansource->gplan = NULL;
281 7468 : plansource->is_oneshot = true;
282 7468 : plansource->is_complete = false;
283 7468 : plansource->is_saved = false;
284 7468 : plansource->is_valid = false;
285 7468 : plansource->generation = 0;
286 7468 : plansource->generic_cost = -1;
287 7468 : plansource->total_custom_cost = 0;
288 7468 : plansource->num_custom_plans = 0;
289 :
290 7468 : return plansource;
291 : }
292 :
293 : /*
294 : * CompleteCachedPlan: second step of creating a plan cache entry.
295 : *
296 : * Pass in the analyzed-and-rewritten form of the query, as well as the
297 : * required subsidiary data about parameters and such. All passed values will
298 : * be copied into the CachedPlanSource's memory, except as specified below.
299 : * After this is called, GetCachedPlan can be called to obtain a plan, and
300 : * optionally the CachedPlanSource can be saved using SaveCachedPlan.
301 : *
302 : * If querytree_context is not NULL, the querytree_list must be stored in that
303 : * context (but the other parameters need not be). The querytree_list is not
304 : * copied, rather the given context is kept as the initial query_context of
305 : * the CachedPlanSource. (It should have been created as a child of the
306 : * caller's working memory context, but it will now be reparented to belong
307 : * to the CachedPlanSource.) The querytree_context is normally the context in
308 : * which the caller did raw parsing and parse analysis. This approach saves
309 : * one tree copying step compared to passing NULL, but leaves lots of extra
310 : * cruft in the query_context, namely whatever extraneous stuff parse analysis
311 : * created, as well as whatever went unused from the raw parse tree. Using
312 : * this option is a space-for-time tradeoff that is appropriate if the
313 : * CachedPlanSource is not expected to survive long.
314 : *
315 : * plancache.c cannot know how to copy the data referenced by parserSetupArg,
316 : * and it would often be inappropriate to do so anyway. When using that
317 : * option, it is caller's responsibility that the referenced data remains
318 : * valid for as long as the CachedPlanSource exists.
319 : *
320 : * If the CachedPlanSource is a "oneshot" plan, then no querytree copying
321 : * occurs at all, and querytree_context is ignored; it is caller's
322 : * responsibility that the passed querytree_list is sufficiently long-lived.
323 : *
324 : * plansource: structure returned by CreateCachedPlan
325 : * querytree_list: analyzed-and-rewritten form of query (list of Query nodes)
326 : * querytree_context: memory context containing querytree_list,
327 : * or NULL to copy querytree_list into a fresh context
328 : * param_types: array of fixed parameter type OIDs, or NULL if none
329 : * num_params: number of fixed parameters
330 : * parserSetup: alternate method for handling query parameters
331 : * parserSetupArg: data to pass to parserSetup
332 : * cursor_options: options bitmask to pass to planner
333 : * fixed_result: true to disallow future changes in query's result tupdesc
334 : */
335 : void
336 32068 : CompleteCachedPlan(CachedPlanSource *plansource,
337 : List *querytree_list,
338 : MemoryContext querytree_context,
339 : Oid *param_types,
340 : int num_params,
341 : ParserSetupHook parserSetup,
342 : void *parserSetupArg,
343 : int cursor_options,
344 : bool fixed_result)
345 : {
346 32068 : MemoryContext source_context = plansource->context;
347 32068 : MemoryContext oldcxt = CurrentMemoryContext;
348 :
349 : /* Assert caller is doing things in a sane order */
350 : Assert(plansource->magic == CACHEDPLANSOURCE_MAGIC);
351 : Assert(!plansource->is_complete);
352 :
353 : /*
354 : * If caller supplied a querytree_context, reparent it underneath the
355 : * CachedPlanSource's context; otherwise, create a suitable context and
356 : * copy the querytree_list into it. But no data copying should be done
357 : * for one-shot plans; for those, assume the passed querytree_list is
358 : * sufficiently long-lived.
359 : */
360 32068 : if (plansource->is_oneshot)
361 : {
362 7450 : querytree_context = CurrentMemoryContext;
363 : }
364 24618 : else if (querytree_context != NULL)
365 : {
366 4328 : MemoryContextSetParent(querytree_context, source_context);
367 4328 : MemoryContextSwitchTo(querytree_context);
368 : }
369 : else
370 : {
371 : /* Again, it's a good bet the querytree_context can be small */
372 20290 : querytree_context = AllocSetContextCreate(source_context,
373 : "CachedPlanQuery",
374 : ALLOCSET_START_SMALL_SIZES);
375 20290 : MemoryContextSwitchTo(querytree_context);
376 20290 : querytree_list = copyObject(querytree_list);
377 : }
378 :
379 32068 : plansource->query_context = querytree_context;
380 32068 : plansource->query_list = querytree_list;
381 :
382 32068 : if (!plansource->is_oneshot && !IsTransactionStmtPlan(plansource))
383 : {
384 : /*
385 : * Use the planner machinery to extract dependencies. Data is saved
386 : * in query_context. (We assume that not a lot of extra cruft is
387 : * created by this call.) We can skip this for one-shot plans, and
388 : * transaction control commands have no such dependencies anyway.
389 : */
390 24128 : extract_query_dependencies((Node *) querytree_list,
391 : &plansource->relationOids,
392 : &plansource->invalItems,
393 : &plansource->dependsOnRLS);
394 :
395 : /* Update RLS info as well. */
396 24128 : plansource->rewriteRoleId = GetUserId();
397 24128 : plansource->rewriteRowSecurity = row_security;
398 :
399 : /*
400 : * Also save the current search_path in the query_context. (This
401 : * should not generate much extra cruft either, since almost certainly
402 : * the path is already valid.) Again, we don't really need this for
403 : * one-shot plans; and we *must* skip this for transaction control
404 : * commands, because this could result in catalog accesses.
405 : */
406 24128 : plansource->search_path = GetOverrideSearchPath(querytree_context);
407 : }
408 :
409 : /*
410 : * Save the final parameter types (or other parameter specification data)
411 : * into the source_context, as well as our other parameters. Also save
412 : * the result tuple descriptor.
413 : */
414 32068 : MemoryContextSwitchTo(source_context);
415 :
416 32068 : if (num_params > 0)
417 : {
418 9494 : plansource->param_types = (Oid *) palloc(num_params * sizeof(Oid));
419 9494 : memcpy(plansource->param_types, param_types, num_params * sizeof(Oid));
420 : }
421 : else
422 22574 : plansource->param_types = NULL;
423 32068 : plansource->num_params = num_params;
424 32068 : plansource->parserSetup = parserSetup;
425 32068 : plansource->parserSetupArg = parserSetupArg;
426 32068 : plansource->cursor_options = cursor_options;
427 32068 : plansource->fixed_result = fixed_result;
428 32068 : plansource->resultDesc = PlanCacheComputeResultDesc(querytree_list);
429 :
430 32068 : MemoryContextSwitchTo(oldcxt);
431 :
432 32068 : plansource->is_complete = true;
433 32068 : plansource->is_valid = true;
434 32068 : }
435 :
436 : /*
437 : * SaveCachedPlan: save a cached plan permanently
438 : *
439 : * This function moves the cached plan underneath CacheMemoryContext (making
440 : * it live for the life of the backend, unless explicitly dropped), and adds
441 : * it to the list of cached plans that are checked for invalidation when an
442 : * sinval event occurs.
443 : *
444 : * This is guaranteed not to throw error, except for the caller-error case
445 : * of trying to save a one-shot plan. Callers typically depend on that
446 : * since this is called just before or just after adding a pointer to the
447 : * CachedPlanSource to some permanent data structure of their own. Up until
448 : * this is done, a CachedPlanSource is just transient data that will go away
449 : * automatically on transaction abort.
450 : */
451 : void
452 21200 : SaveCachedPlan(CachedPlanSource *plansource)
453 : {
454 : /* Assert caller is doing things in a sane order */
455 : Assert(plansource->magic == CACHEDPLANSOURCE_MAGIC);
456 : Assert(plansource->is_complete);
457 : Assert(!plansource->is_saved);
458 :
459 : /* This seems worth a real test, though */
460 21200 : if (plansource->is_oneshot)
461 0 : elog(ERROR, "cannot save one-shot cached plan");
462 :
463 : /*
464 : * In typical use, this function would be called before generating any
465 : * plans from the CachedPlanSource. If there is a generic plan, moving it
466 : * into CacheMemoryContext would be pretty risky since it's unclear
467 : * whether the caller has taken suitable care with making references
468 : * long-lived. Best thing to do seems to be to discard the plan.
469 : */
470 21200 : ReleaseGenericPlan(plansource);
471 :
472 : /*
473 : * Reparent the source memory context under CacheMemoryContext so that it
474 : * will live indefinitely. The query_context follows along since it's
475 : * already a child of the other one.
476 : */
477 21200 : MemoryContextSetParent(plansource->context, CacheMemoryContext);
478 :
479 : /*
480 : * Add the entry to the global list of cached plans.
481 : */
482 21200 : dlist_push_tail(&saved_plan_list, &plansource->node);
483 :
484 21200 : plansource->is_saved = true;
485 21200 : }
486 :
487 : /*
488 : * DropCachedPlan: destroy a cached plan.
489 : *
490 : * Actually this only destroys the CachedPlanSource: any referenced CachedPlan
491 : * is released, but not destroyed until its refcount goes to zero. That
492 : * handles the situation where DropCachedPlan is called while the plan is
493 : * still in use.
494 : */
495 : void
496 10240 : DropCachedPlan(CachedPlanSource *plansource)
497 : {
498 : Assert(plansource->magic == CACHEDPLANSOURCE_MAGIC);
499 :
500 : /* If it's been saved, remove it from the list */
501 10240 : if (plansource->is_saved)
502 : {
503 10098 : dlist_delete(&plansource->node);
504 10098 : plansource->is_saved = false;
505 : }
506 :
507 : /* Decrement generic CachedPlan's refcount and drop if no longer needed */
508 10240 : ReleaseGenericPlan(plansource);
509 :
510 : /* Mark it no longer valid */
511 10240 : plansource->magic = 0;
512 :
513 : /*
514 : * Remove the CachedPlanSource and all subsidiary data (including the
515 : * query_context if any). But if it's a one-shot we can't free anything.
516 : */
517 10240 : if (!plansource->is_oneshot)
518 10240 : MemoryContextDelete(plansource->context);
519 10240 : }
520 :
521 : /*
522 : * ReleaseGenericPlan: release a CachedPlanSource's generic plan, if any.
523 : */
524 : static void
525 50992 : ReleaseGenericPlan(CachedPlanSource *plansource)
526 : {
527 : /* Be paranoid about the possibility that ReleaseCachedPlan fails */
528 50992 : if (plansource->gplan)
529 : {
530 5450 : CachedPlan *plan = plansource->gplan;
531 :
532 : Assert(plan->magic == CACHEDPLAN_MAGIC);
533 5450 : plansource->gplan = NULL;
534 5450 : ReleaseCachedPlan(plan, false);
535 : }
536 50992 : }
537 :
538 : /*
539 : * RevalidateCachedQuery: ensure validity of analyzed-and-rewritten query tree.
540 : *
541 : * What we do here is re-acquire locks and redo parse analysis if necessary.
542 : * On return, the query_list is valid and we have sufficient locks to begin
543 : * planning.
544 : *
545 : * If any parse analysis activity is required, the caller's memory context is
546 : * used for that work.
547 : *
548 : * The result value is the transient analyzed-and-rewritten query tree if we
549 : * had to do re-analysis, and NIL otherwise. (This is returned just to save
550 : * a tree copying step in a subsequent BuildCachedPlan call.)
551 : */
552 : static List *
553 218222 : RevalidateCachedQuery(CachedPlanSource *plansource,
554 : QueryEnvironment *queryEnv)
555 : {
556 : bool snapshot_set;
557 : RawStmt *rawtree;
558 : List *tlist; /* transient query-tree list */
559 : List *qlist; /* permanent query-tree list */
560 : TupleDesc resultDesc;
561 : MemoryContext querytree_context;
562 : MemoryContext oldcxt;
563 :
564 : /*
565 : * For one-shot plans, we do not support revalidation checking; it's
566 : * assumed the query is parsed, planned, and executed in one transaction,
567 : * so that no lock re-acquisition is necessary. Also, there is never any
568 : * need to revalidate plans for transaction control commands (and we
569 : * mustn't risk any catalog accesses when handling those).
570 : */
571 218222 : if (plansource->is_oneshot || IsTransactionStmtPlan(plansource))
572 : {
573 : Assert(plansource->is_valid);
574 8234 : return NIL;
575 : }
576 :
577 : /*
578 : * If the query is currently valid, we should have a saved search_path ---
579 : * check to see if that matches the current environment. If not, we want
580 : * to force replan.
581 : */
582 209988 : if (plansource->is_valid)
583 : {
584 : Assert(plansource->search_path != NULL);
585 207744 : if (!OverrideSearchPathMatchesCurrent(plansource->search_path))
586 : {
587 : /* Invalidate the querytree and generic plan */
588 36 : plansource->is_valid = false;
589 36 : if (plansource->gplan)
590 18 : plansource->gplan->is_valid = false;
591 : }
592 : }
593 :
594 : /*
595 : * If the query rewrite phase had a possible RLS dependency, we must redo
596 : * it if either the role or the row_security setting has changed.
597 : */
598 210148 : if (plansource->is_valid && plansource->dependsOnRLS &&
599 268 : (plansource->rewriteRoleId != GetUserId() ||
600 108 : plansource->rewriteRowSecurity != row_security))
601 52 : plansource->is_valid = false;
602 :
603 : /*
604 : * If the query is currently valid, acquire locks on the referenced
605 : * objects; then check again. We need to do it this way to cover the race
606 : * condition that an invalidation message arrives before we get the locks.
607 : */
608 209988 : if (plansource->is_valid)
609 : {
610 207656 : AcquirePlannerLocks(plansource->query_list, true);
611 :
612 : /*
613 : * By now, if any invalidation has happened, the inval callback
614 : * functions will have marked the query invalid.
615 : */
616 207656 : if (plansource->is_valid)
617 : {
618 : /* Successfully revalidated and locked the query. */
619 207650 : return NIL;
620 : }
621 :
622 : /* Oops, the race case happened. Release useless locks. */
623 6 : AcquirePlannerLocks(plansource->query_list, false);
624 : }
625 :
626 : /*
627 : * Discard the no-longer-useful query tree. (Note: we don't want to do
628 : * this any earlier, else we'd not have been able to release locks
629 : * correctly in the race condition case.)
630 : */
631 2338 : plansource->is_valid = false;
632 2338 : plansource->query_list = NIL;
633 2338 : plansource->relationOids = NIL;
634 2338 : plansource->invalItems = NIL;
635 2338 : plansource->search_path = NULL;
636 :
637 : /*
638 : * Free the query_context. We don't really expect MemoryContextDelete to
639 : * fail, but just in case, make sure the CachedPlanSource is left in a
640 : * reasonably sane state. (The generic plan won't get unlinked yet, but
641 : * that's acceptable.)
642 : */
643 2338 : if (plansource->query_context)
644 : {
645 2322 : MemoryContext qcxt = plansource->query_context;
646 :
647 2322 : plansource->query_context = NULL;
648 2322 : MemoryContextDelete(qcxt);
649 : }
650 :
651 : /* Drop the generic plan reference if any */
652 2338 : ReleaseGenericPlan(plansource);
653 :
654 : /*
655 : * Now re-do parse analysis and rewrite. This not incidentally acquires
656 : * the locks we need to do planning safely.
657 : */
658 : Assert(plansource->is_complete);
659 :
660 : /*
661 : * If a snapshot is already set (the normal case), we can just use that
662 : * for parsing/planning. But if it isn't, install one. Note: no point in
663 : * checking whether parse analysis requires a snapshot; utility commands
664 : * don't have invalidatable plans, so we'd not get here for such a
665 : * command.
666 : */
667 2338 : snapshot_set = false;
668 2338 : if (!ActiveSnapshotSet())
669 : {
670 24 : PushActiveSnapshot(GetTransactionSnapshot());
671 24 : snapshot_set = true;
672 : }
673 :
674 : /*
675 : * Run parse analysis and rule rewriting. The parser tends to scribble on
676 : * its input, so we must copy the raw parse tree to prevent corruption of
677 : * the cache.
678 : */
679 2338 : rawtree = copyObject(plansource->raw_parse_tree);
680 2338 : if (rawtree == NULL)
681 0 : tlist = NIL;
682 2338 : else if (plansource->parserSetup != NULL)
683 2114 : tlist = pg_analyze_and_rewrite_params(rawtree,
684 : plansource->query_string,
685 : plansource->parserSetup,
686 : plansource->parserSetupArg,
687 : queryEnv);
688 : else
689 224 : tlist = pg_analyze_and_rewrite(rawtree,
690 : plansource->query_string,
691 : plansource->param_types,
692 : plansource->num_params,
693 : queryEnv);
694 :
695 : /* Release snapshot if we got one */
696 2322 : if (snapshot_set)
697 24 : PopActiveSnapshot();
698 :
699 : /*
700 : * Check or update the result tupdesc. XXX should we use a weaker
701 : * condition than equalTupleDescs() here?
702 : *
703 : * We assume the parameter types didn't change from the first time, so no
704 : * need to update that.
705 : */
706 2322 : resultDesc = PlanCacheComputeResultDesc(tlist);
707 2322 : if (resultDesc == NULL && plansource->resultDesc == NULL)
708 : {
709 : /* OK, doesn't return tuples */
710 : }
711 4412 : else if (resultDesc == NULL || plansource->resultDesc == NULL ||
712 2206 : !equalTupleDescs(resultDesc, plansource->resultDesc))
713 : {
714 : /* can we give a better error message? */
715 30 : if (plansource->fixed_result)
716 8 : ereport(ERROR,
717 : (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
718 : errmsg("cached plan must not change result type")));
719 22 : oldcxt = MemoryContextSwitchTo(plansource->context);
720 22 : if (resultDesc)
721 22 : resultDesc = CreateTupleDescCopy(resultDesc);
722 22 : if (plansource->resultDesc)
723 22 : FreeTupleDesc(plansource->resultDesc);
724 22 : plansource->resultDesc = resultDesc;
725 22 : MemoryContextSwitchTo(oldcxt);
726 : }
727 :
728 : /*
729 : * Allocate new query_context and copy the completed querytree into it.
730 : * It's transient until we complete the copying and dependency extraction.
731 : */
732 2314 : querytree_context = AllocSetContextCreate(CurrentMemoryContext,
733 : "CachedPlanQuery",
734 : ALLOCSET_START_SMALL_SIZES);
735 2314 : oldcxt = MemoryContextSwitchTo(querytree_context);
736 :
737 2314 : qlist = copyObject(tlist);
738 :
739 : /*
740 : * Use the planner machinery to extract dependencies. Data is saved in
741 : * query_context. (We assume that not a lot of extra cruft is created by
742 : * this call.)
743 : */
744 2314 : extract_query_dependencies((Node *) qlist,
745 : &plansource->relationOids,
746 : &plansource->invalItems,
747 : &plansource->dependsOnRLS);
748 :
749 : /* Update RLS info as well. */
750 2314 : plansource->rewriteRoleId = GetUserId();
751 2314 : plansource->rewriteRowSecurity = row_security;
752 :
753 : /*
754 : * Also save the current search_path in the query_context. (This should
755 : * not generate much extra cruft either, since almost certainly the path
756 : * is already valid.)
757 : */
758 2314 : plansource->search_path = GetOverrideSearchPath(querytree_context);
759 :
760 2314 : MemoryContextSwitchTo(oldcxt);
761 :
762 : /* Now reparent the finished query_context and save the links */
763 2314 : MemoryContextSetParent(querytree_context, plansource->context);
764 :
765 2314 : plansource->query_context = querytree_context;
766 2314 : plansource->query_list = qlist;
767 :
768 : /*
769 : * Note: we do not reset generic_cost or total_custom_cost, although we
770 : * could choose to do so. If the DDL or statistics change that prompted
771 : * the invalidation meant a significant change in the cost estimates, it
772 : * would be better to reset those variables and start fresh; but often it
773 : * doesn't, and we're better retaining our hard-won knowledge about the
774 : * relative costs.
775 : */
776 :
777 2314 : plansource->is_valid = true;
778 :
779 : /* Return transient copy of querytrees for possible use in planning */
780 2314 : return tlist;
781 : }
782 :
783 : /*
784 : * CheckCachedPlan: see if the CachedPlanSource's generic plan is valid.
785 : *
786 : * Caller must have already called RevalidateCachedQuery to verify that the
787 : * querytree is up to date.
788 : *
789 : * On a "true" return, we have acquired the locks needed to run the plan.
790 : * (We must do this for the "true" result to be race-condition-free.)
791 : */
792 : static bool
793 196096 : CheckCachedPlan(CachedPlanSource *plansource)
794 : {
795 196096 : CachedPlan *plan = plansource->gplan;
796 :
797 : /* Assert that caller checked the querytree */
798 : Assert(plansource->is_valid);
799 :
800 : /* If there's no generic plan, just say "false" */
801 196096 : if (!plan)
802 17234 : return false;
803 :
804 : Assert(plan->magic == CACHEDPLAN_MAGIC);
805 : /* Generic plans are never one-shot */
806 : Assert(!plan->is_oneshot);
807 :
808 : /*
809 : * If plan isn't valid for current role, we can't use it.
810 : */
811 178862 : if (plan->is_valid && plan->dependsOnRole &&
812 0 : plan->planRoleId != GetUserId())
813 0 : plan->is_valid = false;
814 :
815 : /*
816 : * If it appears valid, acquire locks and recheck; this is much the same
817 : * logic as in RevalidateCachedQuery, but for a plan.
818 : */
819 178862 : if (plan->is_valid)
820 : {
821 : /*
822 : * Plan must have positive refcount because it is referenced by
823 : * plansource; so no need to fear it disappears under us here.
824 : */
825 : Assert(plan->refcount > 0);
826 :
827 178854 : AcquireExecutorLocks(plan->stmt_list, true);
828 :
829 : /*
830 : * If plan was transient, check to see if TransactionXmin has
831 : * advanced, and if so invalidate it.
832 : */
833 357708 : if (plan->is_valid &&
834 178854 : TransactionIdIsValid(plan->saved_xmin) &&
835 0 : !TransactionIdEquals(plan->saved_xmin, TransactionXmin))
836 0 : plan->is_valid = false;
837 :
838 : /*
839 : * By now, if any invalidation has happened, the inval callback
840 : * functions will have marked the plan invalid.
841 : */
842 178854 : if (plan->is_valid)
843 : {
844 : /* Successfully revalidated and locked the query. */
845 178854 : return true;
846 : }
847 :
848 : /* Oops, the race case happened. Release useless locks. */
849 0 : AcquireExecutorLocks(plan->stmt_list, false);
850 : }
851 :
852 : /*
853 : * Plan has been invalidated, so unlink it from the parent and release it.
854 : */
855 8 : ReleaseGenericPlan(plansource);
856 :
857 8 : return false;
858 : }
859 :
860 : /*
861 : * BuildCachedPlan: construct a new CachedPlan from a CachedPlanSource.
862 : *
863 : * qlist should be the result value from a previous RevalidateCachedQuery,
864 : * or it can be set to NIL if we need to re-copy the plansource's query_list.
865 : *
866 : * To build a generic, parameter-value-independent plan, pass NULL for
867 : * boundParams. To build a custom plan, pass the actual parameter values via
868 : * boundParams. For best effect, the PARAM_FLAG_CONST flag should be set on
869 : * each parameter value; otherwise the planner will treat the value as a
870 : * hint rather than a hard constant.
871 : *
872 : * Planning work is done in the caller's memory context. The finished plan
873 : * is in a child memory context, which typically should get reparented
874 : * (unless this is a one-shot plan, in which case we don't copy the plan).
875 : */
876 : static CachedPlan *
877 38350 : BuildCachedPlan(CachedPlanSource *plansource, List *qlist,
878 : ParamListInfo boundParams, QueryEnvironment *queryEnv)
879 : {
880 : CachedPlan *plan;
881 : List *plist;
882 : bool snapshot_set;
883 : bool is_transient;
884 : MemoryContext plan_context;
885 38350 : MemoryContext oldcxt = CurrentMemoryContext;
886 : ListCell *lc;
887 :
888 : /*
889 : * Normally the querytree should be valid already, but if it's not,
890 : * rebuild it.
891 : *
892 : * NOTE: GetCachedPlan should have called RevalidateCachedQuery first, so
893 : * we ought to be holding sufficient locks to prevent any invalidation.
894 : * However, if we're building a custom plan after having built and
895 : * rejected a generic plan, it's possible to reach here with is_valid
896 : * false due to an invalidation while making the generic plan. In theory
897 : * the invalidation must be a false positive, perhaps a consequence of an
898 : * sinval reset event or the CLOBBER_CACHE_ALWAYS debug code. But for
899 : * safety, let's treat it as real and redo the RevalidateCachedQuery call.
900 : */
901 38350 : if (!plansource->is_valid)
902 0 : qlist = RevalidateCachedQuery(plansource, queryEnv);
903 :
904 : /*
905 : * If we don't already have a copy of the querytree list that can be
906 : * scribbled on by the planner, make one. For a one-shot plan, we assume
907 : * it's okay to scribble on the original query_list.
908 : */
909 38350 : if (qlist == NIL)
910 : {
911 36040 : if (!plansource->is_oneshot)
912 28590 : qlist = copyObject(plansource->query_list);
913 : else
914 7450 : qlist = plansource->query_list;
915 : }
916 :
917 : /*
918 : * If a snapshot is already set (the normal case), we can just use that
919 : * for planning. But if it isn't, and we need one, install one.
920 : */
921 38350 : snapshot_set = false;
922 43134 : if (!ActiveSnapshotSet() &&
923 9568 : plansource->raw_parse_tree &&
924 4784 : analyze_requires_snapshot(plansource->raw_parse_tree))
925 : {
926 4260 : PushActiveSnapshot(GetTransactionSnapshot());
927 4260 : snapshot_set = true;
928 : }
929 :
930 : /*
931 : * Generate the plan.
932 : */
933 38350 : plist = pg_plan_queries(qlist, plansource->cursor_options, boundParams);
934 :
935 : /* Release snapshot if we got one */
936 38296 : if (snapshot_set)
937 4254 : PopActiveSnapshot();
938 :
939 : /*
940 : * Normally we make a dedicated memory context for the CachedPlan and its
941 : * subsidiary data. (It's probably not going to be large, but just in
942 : * case, allow it to grow large. It's transient for the moment.) But for
943 : * a one-shot plan, we just leave it in the caller's memory context.
944 : */
945 38296 : if (!plansource->is_oneshot)
946 : {
947 30850 : plan_context = AllocSetContextCreate(CurrentMemoryContext,
948 : "CachedPlan",
949 : ALLOCSET_START_SMALL_SIZES);
950 30850 : MemoryContextCopyAndSetIdentifier(plan_context, plansource->query_string);
951 :
952 : /*
953 : * Copy plan into the new context.
954 : */
955 30850 : MemoryContextSwitchTo(plan_context);
956 :
957 30850 : plist = copyObject(plist);
958 : }
959 : else
960 7446 : plan_context = CurrentMemoryContext;
961 :
962 : /*
963 : * Create and fill the CachedPlan struct within the new context.
964 : */
965 38296 : plan = (CachedPlan *) palloc(sizeof(CachedPlan));
966 38296 : plan->magic = CACHEDPLAN_MAGIC;
967 38296 : plan->stmt_list = plist;
968 :
969 : /*
970 : * CachedPlan is dependent on role either if RLS affected the rewrite
971 : * phase or if a role dependency was injected during planning. And it's
972 : * transient if any plan is marked so.
973 : */
974 38296 : plan->planRoleId = GetUserId();
975 38296 : plan->dependsOnRole = plansource->dependsOnRLS;
976 38296 : is_transient = false;
977 76592 : foreach(lc, plist)
978 : {
979 38296 : PlannedStmt *plannedstmt = lfirst_node(PlannedStmt, lc);
980 :
981 38296 : if (plannedstmt->commandType == CMD_UTILITY)
982 4618 : continue; /* Ignore utility statements */
983 :
984 33678 : if (plannedstmt->transientPlan)
985 6 : is_transient = true;
986 33678 : if (plannedstmt->dependsOnRole)
987 0 : plan->dependsOnRole = true;
988 : }
989 38296 : if (is_transient)
990 : {
991 : Assert(TransactionIdIsNormal(TransactionXmin));
992 6 : plan->saved_xmin = TransactionXmin;
993 : }
994 : else
995 38290 : plan->saved_xmin = InvalidTransactionId;
996 38296 : plan->refcount = 0;
997 38296 : plan->context = plan_context;
998 38296 : plan->is_oneshot = plansource->is_oneshot;
999 38296 : plan->is_saved = false;
1000 38296 : plan->is_valid = true;
1001 :
1002 : /* assign generation number to new plan */
1003 38296 : plan->generation = ++(plansource->generation);
1004 :
1005 38296 : MemoryContextSwitchTo(oldcxt);
1006 :
1007 38296 : return plan;
1008 : }
1009 :
1010 : /*
1011 : * choose_custom_plan: choose whether to use custom or generic plan
1012 : *
1013 : * This defines the policy followed by GetCachedPlan.
1014 : */
1015 : static bool
1016 234404 : choose_custom_plan(CachedPlanSource *plansource, ParamListInfo boundParams)
1017 : {
1018 : double avg_custom_cost;
1019 :
1020 : /* One-shot plans will always be considered custom */
1021 234404 : if (plansource->is_oneshot)
1022 7450 : return true;
1023 :
1024 : /* Otherwise, never any point in a custom plan if there's no parameters */
1025 226954 : if (boundParams == NULL)
1026 183734 : return false;
1027 : /* ... nor for transaction control statements */
1028 43220 : if (IsTransactionStmtPlan(plansource))
1029 0 : return false;
1030 :
1031 : /* Let settings force the decision */
1032 43220 : if (plan_cache_mode == PLAN_CACHE_MODE_FORCE_GENERIC_PLAN)
1033 48 : return false;
1034 43172 : if (plan_cache_mode == PLAN_CACHE_MODE_FORCE_CUSTOM_PLAN)
1035 4 : return true;
1036 :
1037 : /* See if caller wants to force the decision */
1038 43168 : if (plansource->cursor_options & CURSOR_OPT_GENERIC_PLAN)
1039 0 : return false;
1040 43168 : if (plansource->cursor_options & CURSOR_OPT_CUSTOM_PLAN)
1041 0 : return true;
1042 :
1043 : /* Generate custom plans until we have done at least 5 (arbitrary) */
1044 43168 : if (plansource->num_custom_plans < 5)
1045 13648 : return true;
1046 :
1047 29520 : avg_custom_cost = plansource->total_custom_cost / plansource->num_custom_plans;
1048 :
1049 : /*
1050 : * Prefer generic plan if it's less expensive than the average custom
1051 : * plan. (Because we include a charge for cost of planning in the
1052 : * custom-plan costs, this means the generic plan only has to be less
1053 : * expensive than the execution cost plus replan cost of the custom
1054 : * plans.)
1055 : *
1056 : * Note that if generic_cost is -1 (indicating we've not yet determined
1057 : * the generic plan cost), we'll always prefer generic at this point.
1058 : */
1059 29520 : if (plansource->generic_cost < avg_custom_cost)
1060 29514 : return false;
1061 :
1062 6 : return true;
1063 : }
1064 :
1065 : /*
1066 : * cached_plan_cost: calculate estimated cost of a plan
1067 : *
1068 : * If include_planner is true, also include the estimated cost of constructing
1069 : * the plan. (We must factor that into the cost of using a custom plan, but
1070 : * we don't count it for a generic plan.)
1071 : */
1072 : static double
1073 38296 : cached_plan_cost(CachedPlan *plan, bool include_planner)
1074 : {
1075 38296 : double result = 0;
1076 : ListCell *lc;
1077 :
1078 76592 : foreach(lc, plan->stmt_list)
1079 : {
1080 38296 : PlannedStmt *plannedstmt = lfirst_node(PlannedStmt, lc);
1081 :
1082 38296 : if (plannedstmt->commandType == CMD_UTILITY)
1083 4618 : continue; /* Ignore utility statements */
1084 :
1085 33678 : result += plannedstmt->planTree->total_cost;
1086 :
1087 33678 : if (include_planner)
1088 : {
1089 : /*
1090 : * Currently we use a very crude estimate of planning effort based
1091 : * on the number of relations in the finished plan's rangetable.
1092 : * Join planning effort actually scales much worse than linearly
1093 : * in the number of relations --- but only until the join collapse
1094 : * limits kick in. Also, while inheritance child relations surely
1095 : * add to planning effort, they don't make the join situation
1096 : * worse. So the actual shape of the planning cost curve versus
1097 : * number of relations isn't all that obvious. It will take
1098 : * considerable work to arrive at a less crude estimate, and for
1099 : * now it's not clear that's worth doing.
1100 : *
1101 : * The other big difficulty here is that we don't have any very
1102 : * good model of how planning cost compares to execution costs.
1103 : * The current multiplier of 1000 * cpu_operator_cost is probably
1104 : * on the low side, but we'll try this for awhile before making a
1105 : * more aggressive correction.
1106 : *
1107 : * If we ever do write a more complicated estimator, it should
1108 : * probably live in src/backend/optimizer/ not here.
1109 : */
1110 20052 : int nrelations = list_length(plannedstmt->rtable);
1111 :
1112 20052 : result += 1000.0 * cpu_operator_cost * (nrelations + 1);
1113 : }
1114 : }
1115 :
1116 38296 : return result;
1117 : }
1118 :
1119 : /*
1120 : * GetCachedPlan: get a cached plan from a CachedPlanSource.
1121 : *
1122 : * This function hides the logic that decides whether to use a generic
1123 : * plan or a custom plan for the given parameters: the caller does not know
1124 : * which it will get.
1125 : *
1126 : * On return, the plan is valid and we have sufficient locks to begin
1127 : * execution.
1128 : *
1129 : * On return, the refcount of the plan has been incremented; a later
1130 : * ReleaseCachedPlan() call is expected. The refcount has been reported
1131 : * to the CurrentResourceOwner if useResOwner is true (note that that must
1132 : * only be true if it's a "saved" CachedPlanSource).
1133 : *
1134 : * Note: if any replanning activity is required, the caller's memory context
1135 : * is used for that work.
1136 : */
1137 : CachedPlan *
1138 217222 : GetCachedPlan(CachedPlanSource *plansource, ParamListInfo boundParams,
1139 : bool useResOwner, QueryEnvironment *queryEnv)
1140 : {
1141 217222 : CachedPlan *plan = NULL;
1142 : List *qlist;
1143 : bool customplan;
1144 :
1145 : /* Assert caller is doing things in a sane order */
1146 : Assert(plansource->magic == CACHEDPLANSOURCE_MAGIC);
1147 : Assert(plansource->is_complete);
1148 : /* This seems worth a real test, though */
1149 217222 : if (useResOwner && !plansource->is_saved)
1150 0 : elog(ERROR, "cannot apply ResourceOwner to non-saved cached plan");
1151 :
1152 : /* Make sure the querytree list is valid and we have parse-time locks */
1153 217222 : qlist = RevalidateCachedQuery(plansource, queryEnv);
1154 :
1155 : /* Decide whether to use a custom plan */
1156 217198 : customplan = choose_custom_plan(plansource, boundParams);
1157 :
1158 217198 : if (!customplan)
1159 : {
1160 196096 : if (CheckCachedPlan(plansource))
1161 : {
1162 : /* We want a generic plan, and we already have a valid one */
1163 178854 : plan = plansource->gplan;
1164 : Assert(plan->magic == CACHEDPLAN_MAGIC);
1165 : }
1166 : else
1167 : {
1168 : /* Build a new generic plan */
1169 17242 : plan = BuildCachedPlan(plansource, qlist, NULL, queryEnv);
1170 : /* Just make real sure plansource->gplan is clear */
1171 17206 : ReleaseGenericPlan(plansource);
1172 : /* Link the new generic plan into the plansource */
1173 17206 : plansource->gplan = plan;
1174 17206 : plan->refcount++;
1175 : /* Immediately reparent into appropriate context */
1176 17206 : if (plansource->is_saved)
1177 : {
1178 : /* saved plans all live under CacheMemoryContext */
1179 13854 : MemoryContextSetParent(plan->context, CacheMemoryContext);
1180 13854 : plan->is_saved = true;
1181 : }
1182 : else
1183 : {
1184 : /* otherwise, it should be a sibling of the plansource */
1185 3352 : MemoryContextSetParent(plan->context,
1186 : MemoryContextGetParent(plansource->context));
1187 : }
1188 : /* Update generic_cost whenever we make a new generic plan */
1189 17206 : plansource->generic_cost = cached_plan_cost(plan, false);
1190 :
1191 : /*
1192 : * If, based on the now-known value of generic_cost, we'd not have
1193 : * chosen to use a generic plan, then forget it and make a custom
1194 : * plan. This is a bit of a wart but is necessary to avoid a
1195 : * glitch in behavior when the custom plans are consistently big
1196 : * winners; at some point we'll experiment with a generic plan and
1197 : * find it's a loser, but we don't want to actually execute that
1198 : * plan.
1199 : */
1200 17206 : customplan = choose_custom_plan(plansource, boundParams);
1201 :
1202 : /*
1203 : * If we choose to plan again, we need to re-copy the query_list,
1204 : * since the planner probably scribbled on it. We can force
1205 : * BuildCachedPlan to do that by passing NIL.
1206 : */
1207 17206 : qlist = NIL;
1208 : }
1209 : }
1210 :
1211 217162 : if (customplan)
1212 : {
1213 : /* Build a custom plan */
1214 21108 : plan = BuildCachedPlan(plansource, qlist, boundParams, queryEnv);
1215 : /* Accumulate total costs of custom plans, but 'ware overflow */
1216 21090 : if (plansource->num_custom_plans < INT_MAX)
1217 : {
1218 21090 : plansource->total_custom_cost += cached_plan_cost(plan, true);
1219 21090 : plansource->num_custom_plans++;
1220 : }
1221 : }
1222 :
1223 : Assert(plan != NULL);
1224 :
1225 : /* Flag the plan as in use by caller */
1226 217144 : if (useResOwner)
1227 177622 : ResourceOwnerEnlargePlanCacheRefs(CurrentResourceOwner);
1228 217144 : plan->refcount++;
1229 217144 : if (useResOwner)
1230 177622 : ResourceOwnerRememberPlanCacheRef(CurrentResourceOwner, plan);
1231 :
1232 : /*
1233 : * Saved plans should be under CacheMemoryContext so they will not go away
1234 : * until their reference count goes to zero. In the generic-plan cases we
1235 : * already took care of that, but for a custom plan, do it as soon as we
1236 : * have created a reference-counted link.
1237 : */
1238 217144 : if (customplan && plansource->is_saved)
1239 : {
1240 13578 : MemoryContextSetParent(plan->context, CacheMemoryContext);
1241 13578 : plan->is_saved = true;
1242 : }
1243 :
1244 217144 : return plan;
1245 : }
1246 :
1247 : /*
1248 : * ReleaseCachedPlan: release active use of a cached plan.
1249 : *
1250 : * This decrements the reference count, and frees the plan if the count
1251 : * has thereby gone to zero. If useResOwner is true, it is assumed that
1252 : * the reference count is managed by the CurrentResourceOwner.
1253 : *
1254 : * Note: useResOwner = false is used for releasing references that are in
1255 : * persistent data structures, such as the parent CachedPlanSource or a
1256 : * Portal. Transient references should be protected by a resource owner.
1257 : */
1258 : void
1259 222342 : ReleaseCachedPlan(CachedPlan *plan, bool useResOwner)
1260 : {
1261 : Assert(plan->magic == CACHEDPLAN_MAGIC);
1262 222342 : if (useResOwner)
1263 : {
1264 : Assert(plan->is_saved);
1265 177622 : ResourceOwnerForgetPlanCacheRef(CurrentResourceOwner, plan);
1266 : }
1267 : Assert(plan->refcount > 0);
1268 222342 : plan->refcount--;
1269 222342 : if (plan->refcount == 0)
1270 : {
1271 : /* Mark it no longer valid */
1272 26436 : plan->magic = 0;
1273 :
1274 : /* One-shot plans do not own their context, so we can't free them */
1275 26436 : if (!plan->is_oneshot)
1276 19094 : MemoryContextDelete(plan->context);
1277 : }
1278 222342 : }
1279 :
1280 : /*
1281 : * CachedPlanSetParentContext: move a CachedPlanSource to a new memory context
1282 : *
1283 : * This can only be applied to unsaved plans; once saved, a plan always
1284 : * lives underneath CacheMemoryContext.
1285 : */
1286 : void
1287 13722 : CachedPlanSetParentContext(CachedPlanSource *plansource,
1288 : MemoryContext newcontext)
1289 : {
1290 : /* Assert caller is doing things in a sane order */
1291 : Assert(plansource->magic == CACHEDPLANSOURCE_MAGIC);
1292 : Assert(plansource->is_complete);
1293 :
1294 : /* These seem worth real tests, though */
1295 13722 : if (plansource->is_saved)
1296 0 : elog(ERROR, "cannot move a saved cached plan to another context");
1297 13722 : if (plansource->is_oneshot)
1298 0 : elog(ERROR, "cannot move a one-shot cached plan to another context");
1299 :
1300 : /* OK, let the caller keep the plan where he wishes */
1301 13722 : MemoryContextSetParent(plansource->context, newcontext);
1302 :
1303 : /*
1304 : * The query_context needs no special handling, since it's a child of
1305 : * plansource->context. But if there's a generic plan, it should be
1306 : * maintained as a sibling of plansource->context.
1307 : */
1308 13722 : if (plansource->gplan)
1309 : {
1310 : Assert(plansource->gplan->magic == CACHEDPLAN_MAGIC);
1311 0 : MemoryContextSetParent(plansource->gplan->context, newcontext);
1312 : }
1313 13722 : }
1314 :
1315 : /*
1316 : * CopyCachedPlan: make a copy of a CachedPlanSource
1317 : *
1318 : * This is a convenience routine that does the equivalent of
1319 : * CreateCachedPlan + CompleteCachedPlan, using the data stored in the
1320 : * input CachedPlanSource. The result is therefore "unsaved" (regardless
1321 : * of the state of the source), and we don't copy any generic plan either.
1322 : * The result will be currently valid, or not, the same as the source.
1323 : */
1324 : CachedPlanSource *
1325 0 : CopyCachedPlan(CachedPlanSource *plansource)
1326 : {
1327 : CachedPlanSource *newsource;
1328 : MemoryContext source_context;
1329 : MemoryContext querytree_context;
1330 : MemoryContext oldcxt;
1331 :
1332 : Assert(plansource->magic == CACHEDPLANSOURCE_MAGIC);
1333 : Assert(plansource->is_complete);
1334 :
1335 : /*
1336 : * One-shot plans can't be copied, because we haven't taken care that
1337 : * parsing/planning didn't scribble on the raw parse tree or querytrees.
1338 : */
1339 0 : if (plansource->is_oneshot)
1340 0 : elog(ERROR, "cannot copy a one-shot cached plan");
1341 :
1342 0 : source_context = AllocSetContextCreate(CurrentMemoryContext,
1343 : "CachedPlanSource",
1344 : ALLOCSET_START_SMALL_SIZES);
1345 :
1346 0 : oldcxt = MemoryContextSwitchTo(source_context);
1347 :
1348 0 : newsource = (CachedPlanSource *) palloc0(sizeof(CachedPlanSource));
1349 0 : newsource->magic = CACHEDPLANSOURCE_MAGIC;
1350 0 : newsource->raw_parse_tree = copyObject(plansource->raw_parse_tree);
1351 0 : newsource->query_string = pstrdup(plansource->query_string);
1352 0 : MemoryContextSetIdentifier(source_context, newsource->query_string);
1353 0 : newsource->commandTag = plansource->commandTag;
1354 0 : if (plansource->num_params > 0)
1355 : {
1356 0 : newsource->param_types = (Oid *)
1357 0 : palloc(plansource->num_params * sizeof(Oid));
1358 0 : memcpy(newsource->param_types, plansource->param_types,
1359 0 : plansource->num_params * sizeof(Oid));
1360 : }
1361 : else
1362 0 : newsource->param_types = NULL;
1363 0 : newsource->num_params = plansource->num_params;
1364 0 : newsource->parserSetup = plansource->parserSetup;
1365 0 : newsource->parserSetupArg = plansource->parserSetupArg;
1366 0 : newsource->cursor_options = plansource->cursor_options;
1367 0 : newsource->fixed_result = plansource->fixed_result;
1368 0 : if (plansource->resultDesc)
1369 0 : newsource->resultDesc = CreateTupleDescCopy(plansource->resultDesc);
1370 : else
1371 0 : newsource->resultDesc = NULL;
1372 0 : newsource->context = source_context;
1373 :
1374 0 : querytree_context = AllocSetContextCreate(source_context,
1375 : "CachedPlanQuery",
1376 : ALLOCSET_START_SMALL_SIZES);
1377 0 : MemoryContextSwitchTo(querytree_context);
1378 0 : newsource->query_list = copyObject(plansource->query_list);
1379 0 : newsource->relationOids = copyObject(plansource->relationOids);
1380 0 : newsource->invalItems = copyObject(plansource->invalItems);
1381 0 : if (plansource->search_path)
1382 0 : newsource->search_path = CopyOverrideSearchPath(plansource->search_path);
1383 0 : newsource->query_context = querytree_context;
1384 0 : newsource->rewriteRoleId = plansource->rewriteRoleId;
1385 0 : newsource->rewriteRowSecurity = plansource->rewriteRowSecurity;
1386 0 : newsource->dependsOnRLS = plansource->dependsOnRLS;
1387 :
1388 0 : newsource->gplan = NULL;
1389 :
1390 0 : newsource->is_oneshot = false;
1391 0 : newsource->is_complete = true;
1392 0 : newsource->is_saved = false;
1393 0 : newsource->is_valid = plansource->is_valid;
1394 0 : newsource->generation = plansource->generation;
1395 :
1396 : /* We may as well copy any acquired cost knowledge */
1397 0 : newsource->generic_cost = plansource->generic_cost;
1398 0 : newsource->total_custom_cost = plansource->total_custom_cost;
1399 0 : newsource->num_custom_plans = plansource->num_custom_plans;
1400 :
1401 0 : MemoryContextSwitchTo(oldcxt);
1402 :
1403 0 : return newsource;
1404 : }
1405 :
1406 : /*
1407 : * CachedPlanIsValid: test whether the rewritten querytree within a
1408 : * CachedPlanSource is currently valid (that is, not marked as being in need
1409 : * of revalidation).
1410 : *
1411 : * This result is only trustworthy (ie, free from race conditions) if
1412 : * the caller has acquired locks on all the relations used in the plan.
1413 : */
1414 : bool
1415 1676 : CachedPlanIsValid(CachedPlanSource *plansource)
1416 : {
1417 : Assert(plansource->magic == CACHEDPLANSOURCE_MAGIC);
1418 1676 : return plansource->is_valid;
1419 : }
1420 :
1421 : /*
1422 : * CachedPlanGetTargetList: return tlist, if any, describing plan's output
1423 : *
1424 : * The result is guaranteed up-to-date. However, it is local storage
1425 : * within the cached plan, and may disappear next time the plan is updated.
1426 : */
1427 : List *
1428 1000 : CachedPlanGetTargetList(CachedPlanSource *plansource,
1429 : QueryEnvironment *queryEnv)
1430 : {
1431 : Query *pstmt;
1432 :
1433 : /* Assert caller is doing things in a sane order */
1434 : Assert(plansource->magic == CACHEDPLANSOURCE_MAGIC);
1435 : Assert(plansource->is_complete);
1436 :
1437 : /*
1438 : * No work needed if statement doesn't return tuples (we assume this
1439 : * feature cannot be changed by an invalidation)
1440 : */
1441 1000 : if (plansource->resultDesc == NULL)
1442 0 : return NIL;
1443 :
1444 : /* Make sure the querytree list is valid and we have parse-time locks */
1445 1000 : RevalidateCachedQuery(plansource, queryEnv);
1446 :
1447 : /* Get the primary statement and find out what it returns */
1448 1000 : pstmt = QueryListGetPrimaryStmt(plansource->query_list);
1449 :
1450 1000 : return FetchStatementTargetList((Node *) pstmt);
1451 : }
1452 :
1453 : /*
1454 : * GetCachedExpression: construct a CachedExpression for an expression.
1455 : *
1456 : * This performs the same transformations on the expression as
1457 : * expression_planner(), ie, convert an expression as emitted by parse
1458 : * analysis to be ready to pass to the executor.
1459 : *
1460 : * The result is stashed in a private, long-lived memory context.
1461 : * (Note that this might leak a good deal of memory in the caller's
1462 : * context before that.) The passed-in expr tree is not modified.
1463 : */
1464 : CachedExpression *
1465 328 : GetCachedExpression(Node *expr)
1466 : {
1467 : CachedExpression *cexpr;
1468 : List *relationOids;
1469 : List *invalItems;
1470 : MemoryContext cexpr_context;
1471 : MemoryContext oldcxt;
1472 :
1473 : /*
1474 : * Pass the expression through the planner, and collect dependencies.
1475 : * Everything built here is leaked in the caller's context; that's
1476 : * intentional to minimize the size of the permanent data structure.
1477 : */
1478 328 : expr = (Node *) expression_planner_with_deps((Expr *) expr,
1479 : &relationOids,
1480 : &invalItems);
1481 :
1482 : /*
1483 : * Make a private memory context, and copy what we need into that. To
1484 : * avoid leaking a long-lived context if we fail while copying data, we
1485 : * initially make the context under the caller's context.
1486 : */
1487 328 : cexpr_context = AllocSetContextCreate(CurrentMemoryContext,
1488 : "CachedExpression",
1489 : ALLOCSET_SMALL_SIZES);
1490 :
1491 328 : oldcxt = MemoryContextSwitchTo(cexpr_context);
1492 :
1493 328 : cexpr = (CachedExpression *) palloc(sizeof(CachedExpression));
1494 328 : cexpr->magic = CACHEDEXPR_MAGIC;
1495 328 : cexpr->expr = copyObject(expr);
1496 328 : cexpr->is_valid = true;
1497 328 : cexpr->relationOids = copyObject(relationOids);
1498 328 : cexpr->invalItems = copyObject(invalItems);
1499 328 : cexpr->context = cexpr_context;
1500 :
1501 328 : MemoryContextSwitchTo(oldcxt);
1502 :
1503 : /*
1504 : * Reparent the expr's memory context under CacheMemoryContext so that it
1505 : * will live indefinitely.
1506 : */
1507 328 : MemoryContextSetParent(cexpr_context, CacheMemoryContext);
1508 :
1509 : /*
1510 : * Add the entry to the global list of cached expressions.
1511 : */
1512 328 : dlist_push_tail(&cached_expression_list, &cexpr->node);
1513 :
1514 328 : return cexpr;
1515 : }
1516 :
1517 : /*
1518 : * FreeCachedExpression
1519 : * Delete a CachedExpression.
1520 : */
1521 : void
1522 40 : FreeCachedExpression(CachedExpression *cexpr)
1523 : {
1524 : /* Sanity check */
1525 : Assert(cexpr->magic == CACHEDEXPR_MAGIC);
1526 : /* Unlink from global list */
1527 40 : dlist_delete(&cexpr->node);
1528 : /* Free all storage associated with CachedExpression */
1529 40 : MemoryContextDelete(cexpr->context);
1530 40 : }
1531 :
1532 : /*
1533 : * QueryListGetPrimaryStmt
1534 : * Get the "primary" stmt within a list, ie, the one marked canSetTag.
1535 : *
1536 : * Returns NULL if no such stmt. If multiple queries within the list are
1537 : * marked canSetTag, returns the first one. Neither of these cases should
1538 : * occur in present usages of this function.
1539 : */
1540 : static Query *
1541 1166 : QueryListGetPrimaryStmt(List *stmts)
1542 : {
1543 : ListCell *lc;
1544 :
1545 1166 : foreach(lc, stmts)
1546 : {
1547 1166 : Query *stmt = lfirst_node(Query, lc);
1548 :
1549 1166 : if (stmt->canSetTag)
1550 1166 : return stmt;
1551 : }
1552 0 : return NULL;
1553 : }
1554 :
1555 : /*
1556 : * AcquireExecutorLocks: acquire locks needed for execution of a cached plan;
1557 : * or release them if acquire is false.
1558 : */
1559 : static void
1560 178854 : AcquireExecutorLocks(List *stmt_list, bool acquire)
1561 : {
1562 : ListCell *lc1;
1563 :
1564 357708 : foreach(lc1, stmt_list)
1565 : {
1566 178854 : PlannedStmt *plannedstmt = lfirst_node(PlannedStmt, lc1);
1567 : ListCell *lc2;
1568 :
1569 178854 : if (plannedstmt->commandType == CMD_UTILITY)
1570 : {
1571 : /*
1572 : * Ignore utility statements, except those (such as EXPLAIN) that
1573 : * contain a parsed-but-not-planned query. Note: it's okay to use
1574 : * ScanQueryForLocks, even though the query hasn't been through
1575 : * rule rewriting, because rewriting doesn't change the query
1576 : * representation.
1577 : */
1578 4750 : Query *query = UtilityContainsQuery(plannedstmt->utilityStmt);
1579 :
1580 4750 : if (query)
1581 4 : ScanQueryForLocks(query, acquire);
1582 4750 : continue;
1583 : }
1584 :
1585 356060 : foreach(lc2, plannedstmt->rtable)
1586 : {
1587 181956 : RangeTblEntry *rte = (RangeTblEntry *) lfirst(lc2);
1588 :
1589 181956 : if (rte->rtekind != RTE_RELATION)
1590 169150 : continue;
1591 :
1592 : /*
1593 : * Acquire the appropriate type of lock on each relation OID. Note
1594 : * that we don't actually try to open the rel, and hence will not
1595 : * fail if it's been dropped entirely --- we'll just transiently
1596 : * acquire a non-conflicting lock.
1597 : */
1598 12806 : if (acquire)
1599 12806 : LockRelationOid(rte->relid, rte->rellockmode);
1600 : else
1601 0 : UnlockRelationOid(rte->relid, rte->rellockmode);
1602 : }
1603 : }
1604 178854 : }
1605 :
1606 : /*
1607 : * AcquirePlannerLocks: acquire locks needed for planning of a querytree list;
1608 : * or release them if acquire is false.
1609 : *
1610 : * Note that we don't actually try to open the relations, and hence will not
1611 : * fail if one has been dropped entirely --- we'll just transiently acquire
1612 : * a non-conflicting lock.
1613 : */
1614 : static void
1615 207662 : AcquirePlannerLocks(List *stmt_list, bool acquire)
1616 : {
1617 : ListCell *lc;
1618 :
1619 415324 : foreach(lc, stmt_list)
1620 : {
1621 207662 : Query *query = lfirst_node(Query, lc);
1622 :
1623 207662 : if (query->commandType == CMD_UTILITY)
1624 : {
1625 : /* Ignore utility statements, unless they contain a Query */
1626 8292 : query = UtilityContainsQuery(query->utilityStmt);
1627 8292 : if (query)
1628 3640 : ScanQueryForLocks(query, acquire);
1629 8292 : continue;
1630 : }
1631 :
1632 199370 : ScanQueryForLocks(query, acquire);
1633 : }
1634 207662 : }
1635 :
1636 : /*
1637 : * ScanQueryForLocks: recursively scan one Query for AcquirePlannerLocks.
1638 : */
1639 : static void
1640 206880 : ScanQueryForLocks(Query *parsetree, bool acquire)
1641 : {
1642 : ListCell *lc;
1643 :
1644 : /* Shouldn't get called on utility commands */
1645 : Assert(parsetree->commandType != CMD_UTILITY);
1646 :
1647 : /*
1648 : * First, process RTEs of the current query level.
1649 : */
1650 242234 : foreach(lc, parsetree->rtable)
1651 : {
1652 35354 : RangeTblEntry *rte = (RangeTblEntry *) lfirst(lc);
1653 :
1654 35354 : switch (rte->rtekind)
1655 : {
1656 : case RTE_RELATION:
1657 : /* Acquire or release the appropriate type of lock */
1658 31468 : if (acquire)
1659 31462 : LockRelationOid(rte->relid, rte->rellockmode);
1660 : else
1661 6 : UnlockRelationOid(rte->relid, rte->rellockmode);
1662 31468 : break;
1663 :
1664 : case RTE_SUBQUERY:
1665 : /* Recurse into subquery-in-FROM */
1666 450 : ScanQueryForLocks(rte->subquery, acquire);
1667 450 : break;
1668 :
1669 : default:
1670 : /* ignore other types of RTEs */
1671 3436 : break;
1672 : }
1673 : }
1674 :
1675 : /* Recurse into subquery-in-WITH */
1676 206892 : foreach(lc, parsetree->cteList)
1677 : {
1678 12 : CommonTableExpr *cte = lfirst_node(CommonTableExpr, lc);
1679 :
1680 12 : ScanQueryForLocks(castNode(Query, cte->ctequery), acquire);
1681 : }
1682 :
1683 : /*
1684 : * Recurse into sublink subqueries, too. But we already did the ones in
1685 : * the rtable and cteList.
1686 : */
1687 206880 : if (parsetree->hasSubLinks)
1688 : {
1689 3400 : query_tree_walker(parsetree, ScanQueryWalker,
1690 : (void *) &acquire,
1691 : QTW_IGNORE_RC_SUBQUERIES);
1692 : }
1693 206880 : }
1694 :
1695 : /*
1696 : * Walker to find sublink subqueries for ScanQueryForLocks
1697 : */
1698 : static bool
1699 54068 : ScanQueryWalker(Node *node, bool *acquire)
1700 : {
1701 54068 : if (node == NULL)
1702 34064 : return false;
1703 20004 : if (IsA(node, SubLink))
1704 : {
1705 3404 : SubLink *sub = (SubLink *) node;
1706 :
1707 : /* Do what we came for */
1708 3404 : ScanQueryForLocks(castNode(Query, sub->subselect), *acquire);
1709 : /* Fall through to process lefthand args of SubLink */
1710 : }
1711 :
1712 : /*
1713 : * Do NOT recurse into Query nodes, because ScanQueryForLocks already
1714 : * processed subselects of subselects for us.
1715 : */
1716 20004 : return expression_tree_walker(node, ScanQueryWalker,
1717 : (void *) acquire);
1718 : }
1719 :
1720 : /*
1721 : * PlanCacheComputeResultDesc: given a list of analyzed-and-rewritten Queries,
1722 : * determine the result tupledesc it will produce. Returns NULL if the
1723 : * execution will not return tuples.
1724 : *
1725 : * Note: the result is created or copied into current memory context.
1726 : */
1727 : static TupleDesc
1728 34390 : PlanCacheComputeResultDesc(List *stmt_list)
1729 : {
1730 : Query *query;
1731 :
1732 34390 : switch (ChoosePortalStrategy(stmt_list))
1733 : {
1734 : case PORTAL_ONE_SELECT:
1735 : case PORTAL_ONE_MOD_WITH:
1736 23000 : query = linitial_node(Query, stmt_list);
1737 23000 : return ExecCleanTypeFromTL(query->targetList);
1738 :
1739 : case PORTAL_ONE_RETURNING:
1740 166 : query = QueryListGetPrimaryStmt(stmt_list);
1741 : Assert(query->returningList);
1742 166 : return ExecCleanTypeFromTL(query->returningList);
1743 :
1744 : case PORTAL_UTIL_SELECT:
1745 2424 : query = linitial_node(Query, stmt_list);
1746 : Assert(query->utilityStmt);
1747 2424 : return UtilityTupleDescriptor(query->utilityStmt);
1748 :
1749 : case PORTAL_MULTI_QUERY:
1750 : /* will not return tuples */
1751 8800 : break;
1752 : }
1753 8800 : return NULL;
1754 : }
1755 :
1756 : /*
1757 : * PlanCacheRelCallback
1758 : * Relcache inval callback function
1759 : *
1760 : * Invalidate all plans mentioning the given rel, or all plans mentioning
1761 : * any rel at all if relid == InvalidOid.
1762 : */
1763 : static void
1764 1314490 : PlanCacheRelCallback(Datum arg, Oid relid)
1765 : {
1766 : dlist_iter iter;
1767 :
1768 17901724 : dlist_foreach(iter, &saved_plan_list)
1769 : {
1770 16587234 : CachedPlanSource *plansource = dlist_container(CachedPlanSource,
1771 : node, iter.cur);
1772 :
1773 : Assert(plansource->magic == CACHEDPLANSOURCE_MAGIC);
1774 :
1775 : /* No work if it's already invalidated */
1776 16587234 : if (!plansource->is_valid)
1777 7879196 : continue;
1778 :
1779 : /* Never invalidate transaction control commands */
1780 8708038 : if (IsTransactionStmtPlan(plansource))
1781 0 : continue;
1782 :
1783 : /*
1784 : * Check the dependency list for the rewritten querytree.
1785 : */
1786 17415704 : if ((relid == InvalidOid) ? plansource->relationOids != NIL :
1787 8707666 : list_member_oid(plansource->relationOids, relid))
1788 : {
1789 : /* Invalidate the querytree and generic plan */
1790 1912 : plansource->is_valid = false;
1791 1912 : if (plansource->gplan)
1792 540 : plansource->gplan->is_valid = false;
1793 : }
1794 :
1795 : /*
1796 : * The generic plan, if any, could have more dependencies than the
1797 : * querytree does, so we have to check it too.
1798 : */
1799 8708038 : if (plansource->gplan && plansource->gplan->is_valid)
1800 : {
1801 : ListCell *lc;
1802 :
1803 16608786 : foreach(lc, plansource->gplan->stmt_list)
1804 : {
1805 8304402 : PlannedStmt *plannedstmt = lfirst_node(PlannedStmt, lc);
1806 :
1807 8304402 : if (plannedstmt->commandType == CMD_UTILITY)
1808 50056 : continue; /* Ignore utility statements */
1809 16508692 : if ((relid == InvalidOid) ? plannedstmt->relationOids != NIL :
1810 8254346 : list_member_oid(plannedstmt->relationOids, relid))
1811 : {
1812 : /* Invalidate the generic plan only */
1813 18 : plansource->gplan->is_valid = false;
1814 18 : break; /* out of stmt_list scan */
1815 : }
1816 : }
1817 : }
1818 : }
1819 :
1820 : /* Likewise check cached expressions */
1821 1489414 : dlist_foreach(iter, &cached_expression_list)
1822 : {
1823 174924 : CachedExpression *cexpr = dlist_container(CachedExpression,
1824 : node, iter.cur);
1825 :
1826 : Assert(cexpr->magic == CACHEDEXPR_MAGIC);
1827 :
1828 : /* No work if it's already invalidated */
1829 174924 : if (!cexpr->is_valid)
1830 57104 : continue;
1831 :
1832 235640 : if ((relid == InvalidOid) ? cexpr->relationOids != NIL :
1833 117820 : list_member_oid(cexpr->relationOids, relid))
1834 : {
1835 0 : cexpr->is_valid = false;
1836 : }
1837 : }
1838 1314490 : }
1839 :
1840 : /*
1841 : * PlanCacheObjectCallback
1842 : * Syscache inval callback function for PROCOID and TYPEOID caches
1843 : *
1844 : * Invalidate all plans mentioning the object with the specified hash value,
1845 : * or all plans mentioning any member of this cache if hashvalue == 0.
1846 : */
1847 : static void
1848 593450 : PlanCacheObjectCallback(Datum arg, int cacheid, uint32 hashvalue)
1849 : {
1850 : dlist_iter iter;
1851 :
1852 9090530 : dlist_foreach(iter, &saved_plan_list)
1853 : {
1854 8497080 : CachedPlanSource *plansource = dlist_container(CachedPlanSource,
1855 : node, iter.cur);
1856 : ListCell *lc;
1857 :
1858 : Assert(plansource->magic == CACHEDPLANSOURCE_MAGIC);
1859 :
1860 : /* No work if it's already invalidated */
1861 8497080 : if (!plansource->is_valid)
1862 3457924 : continue;
1863 :
1864 : /* Never invalidate transaction control commands */
1865 5039156 : if (IsTransactionStmtPlan(plansource))
1866 0 : continue;
1867 :
1868 : /*
1869 : * Check the dependency list for the rewritten querytree.
1870 : */
1871 5158226 : foreach(lc, plansource->invalItems)
1872 : {
1873 119112 : PlanInvalItem *item = (PlanInvalItem *) lfirst(lc);
1874 :
1875 119112 : if (item->cacheId != cacheid)
1876 77246 : continue;
1877 83732 : if (hashvalue == 0 ||
1878 41866 : item->hashValue == hashvalue)
1879 : {
1880 : /* Invalidate the querytree and generic plan */
1881 42 : plansource->is_valid = false;
1882 42 : if (plansource->gplan)
1883 40 : plansource->gplan->is_valid = false;
1884 42 : break;
1885 : }
1886 : }
1887 :
1888 : /*
1889 : * The generic plan, if any, could have more dependencies than the
1890 : * querytree does, so we have to check it too.
1891 : */
1892 5039156 : if (plansource->gplan && plansource->gplan->is_valid)
1893 : {
1894 9550924 : foreach(lc, plansource->gplan->stmt_list)
1895 : {
1896 4775464 : PlannedStmt *plannedstmt = lfirst_node(PlannedStmt, lc);
1897 : ListCell *lc3;
1898 :
1899 4775464 : if (plannedstmt->commandType == CMD_UTILITY)
1900 38086 : continue; /* Ignore utility statements */
1901 4856292 : foreach(lc3, plannedstmt->invalItems)
1902 : {
1903 118918 : PlanInvalItem *item = (PlanInvalItem *) lfirst(lc3);
1904 :
1905 118918 : if (item->cacheId != cacheid)
1906 77074 : continue;
1907 83688 : if (hashvalue == 0 ||
1908 41844 : item->hashValue == hashvalue)
1909 : {
1910 : /* Invalidate the generic plan only */
1911 4 : plansource->gplan->is_valid = false;
1912 4 : break; /* out of invalItems scan */
1913 : }
1914 : }
1915 4737378 : if (!plansource->gplan->is_valid)
1916 4 : break; /* out of stmt_list scan */
1917 : }
1918 : }
1919 : }
1920 :
1921 : /* Likewise check cached expressions */
1922 698914 : dlist_foreach(iter, &cached_expression_list)
1923 : {
1924 105464 : CachedExpression *cexpr = dlist_container(CachedExpression,
1925 : node, iter.cur);
1926 : ListCell *lc;
1927 :
1928 : Assert(cexpr->magic == CACHEDEXPR_MAGIC);
1929 :
1930 : /* No work if it's already invalidated */
1931 105464 : if (!cexpr->is_valid)
1932 27072 : continue;
1933 :
1934 79698 : foreach(lc, cexpr->invalItems)
1935 : {
1936 1314 : PlanInvalItem *item = (PlanInvalItem *) lfirst(lc);
1937 :
1938 1314 : if (item->cacheId != cacheid)
1939 310 : continue;
1940 2008 : if (hashvalue == 0 ||
1941 1004 : item->hashValue == hashvalue)
1942 : {
1943 8 : cexpr->is_valid = false;
1944 8 : break;
1945 : }
1946 : }
1947 : }
1948 593450 : }
1949 :
1950 : /*
1951 : * PlanCacheSysCallback
1952 : * Syscache inval callback function for other caches
1953 : *
1954 : * Just invalidate everything...
1955 : */
1956 : static void
1957 36338 : PlanCacheSysCallback(Datum arg, int cacheid, uint32 hashvalue)
1958 : {
1959 36338 : ResetPlanCache();
1960 36338 : }
1961 :
1962 : /*
1963 : * ResetPlanCache: invalidate all cached plans.
1964 : */
1965 : void
1966 36492 : ResetPlanCache(void)
1967 : {
1968 : dlist_iter iter;
1969 :
1970 115534 : dlist_foreach(iter, &saved_plan_list)
1971 : {
1972 79042 : CachedPlanSource *plansource = dlist_container(CachedPlanSource,
1973 : node, iter.cur);
1974 : ListCell *lc;
1975 :
1976 : Assert(plansource->magic == CACHEDPLANSOURCE_MAGIC);
1977 :
1978 : /* No work if it's already invalidated */
1979 79042 : if (!plansource->is_valid)
1980 71656 : continue;
1981 :
1982 : /*
1983 : * We *must not* mark transaction control statements as invalid,
1984 : * particularly not ROLLBACK, because they may need to be executed in
1985 : * aborted transactions when we can't revalidate them (cf bug #5269).
1986 : */
1987 7386 : if (IsTransactionStmtPlan(plansource))
1988 0 : continue;
1989 :
1990 : /*
1991 : * In general there is no point in invalidating utility statements
1992 : * since they have no plans anyway. So invalidate it only if it
1993 : * contains at least one non-utility statement, or contains a utility
1994 : * statement that contains a pre-analyzed query (which could have
1995 : * dependencies.)
1996 : */
1997 10096 : foreach(lc, plansource->query_list)
1998 : {
1999 7386 : Query *query = lfirst_node(Query, lc);
2000 :
2001 10096 : if (query->commandType != CMD_UTILITY ||
2002 2710 : UtilityContainsQuery(query->utilityStmt))
2003 : {
2004 : /* non-utility statement, so invalidate */
2005 4676 : plansource->is_valid = false;
2006 4676 : if (plansource->gplan)
2007 4264 : plansource->gplan->is_valid = false;
2008 : /* no need to look further */
2009 4676 : break;
2010 : }
2011 : }
2012 : }
2013 :
2014 : /* Likewise invalidate cached expressions */
2015 37018 : dlist_foreach(iter, &cached_expression_list)
2016 : {
2017 526 : CachedExpression *cexpr = dlist_container(CachedExpression,
2018 : node, iter.cur);
2019 :
2020 : Assert(cexpr->magic == CACHEDEXPR_MAGIC);
2021 :
2022 526 : cexpr->is_valid = false;
2023 : }
2024 36492 : }
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