diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/backend/utils/cache/plancache.c | 54 |
1 files changed, 47 insertions, 7 deletions
diff --git a/src/backend/utils/cache/plancache.c b/src/backend/utils/cache/plancache.c index a47fa3375f7..75810caa732 100644 --- a/src/backend/utils/cache/plancache.c +++ b/src/backend/utils/cache/plancache.c @@ -33,7 +33,7 @@ * Portions Copyright (c) 1994, Regents of the University of California * * IDENTIFICATION - * $PostgreSQL: pgsql/src/backend/utils/cache/plancache.c,v 1.8 2007/04/16 18:21:07 tgl Exp $ + * $PostgreSQL: pgsql/src/backend/utils/cache/plancache.c,v 1.9 2007/05/14 18:13:21 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -69,6 +69,7 @@ static List *cached_plans_list = NIL; static void StoreCachedPlan(CachedPlanSource *plansource, List *stmt_list, MemoryContext plan_context); +static List *do_planning(List *querytrees, int cursorOptions); static void AcquireExecutorLocks(List *stmt_list, bool acquire); static void AcquirePlannerLocks(List *stmt_list, bool acquire); static void LockRelid(Oid relid, LOCKMODE lockmode, void *arg); @@ -462,12 +463,8 @@ RevalidateCachedPlan(CachedPlanSource *plansource, bool useResOwner) if (plansource->fully_planned) { - /* - * Generate plans for queries. Assume snapshot is not set yet - * (XXX this may be wasteful, won't all callers have done that?) - */ - slist = pg_plan_queries(slist, plansource->cursor_options, NULL, - true); + /* Generate plans for queries */ + slist = do_planning(slist, plansource->cursor_options); } /* @@ -523,6 +520,49 @@ RevalidateCachedPlan(CachedPlanSource *plansource, bool useResOwner) } /* + * Invoke the planner on some rewritten queries. This is broken out of + * RevalidateCachedPlan just to avoid plastering "volatile" all over that + * function's variables. + */ +static List * +do_planning(List *querytrees, int cursorOptions) +{ + List *stmt_list; + + /* + * If a snapshot is already set (the normal case), we can just use that + * for planning. But if it isn't, we have to tell pg_plan_queries to make + * a snap if it needs one. In that case we should arrange to reset + * ActiveSnapshot afterward, to ensure that RevalidateCachedPlan has no + * caller-visible effects on the snapshot. Having to replan is an unusual + * case, and it seems a really bad idea for RevalidateCachedPlan to affect + * the snapshot only in unusual cases. (Besides, the snap might have + * been created in a short-lived context.) + */ + if (ActiveSnapshot != NULL) + stmt_list = pg_plan_queries(querytrees, cursorOptions, NULL, false); + else + { + PG_TRY(); + { + stmt_list = pg_plan_queries(querytrees, cursorOptions, NULL, true); + } + PG_CATCH(); + { + /* Restore global vars and propagate error */ + ActiveSnapshot = NULL; + PG_RE_THROW(); + } + PG_END_TRY(); + + ActiveSnapshot = NULL; + } + + return stmt_list; +} + + +/* * ReleaseCachedPlan: release active use of a cached plan. * * This decrements the reference count, and frees the plan if the count |