plancache.h File Reference

#include "access/tupdesc.h"
#include "lib/ilist.h"
#include "nodes/params.h"
#include "nodes/parsenodes.h"
#include "nodes/plannodes.h"
#include "tcop/cmdtag.h"
#include "utils/queryenvironment.h"
#include "utils/resowner.h"

Include dependency graph for plancache.h:

This graph shows which files directly or indirectly include this file:

Go to the source code of this file.

Data Structures
struct	CachedPlanSource
struct	CachedPlan
struct	CachedExpression

Macros
#define	CACHEDPLANSOURCE_MAGIC   195726186
#define	CACHEDPLAN_MAGIC   953717834
#define	CACHEDEXPR_MAGIC   838275847

Typedefs
typedef void(*	PostRewriteHook) (List *querytree_list, void *arg)
typedef struct CachedPlanSource	CachedPlanSource
typedef struct CachedPlan	CachedPlan
typedef struct CachedExpression	CachedExpression

Enumerations
enum	PlanCacheMode { PLAN_CACHE_MODE_AUTO , PLAN_CACHE_MODE_FORCE_GENERIC_PLAN , PLAN_CACHE_MODE_FORCE_CUSTOM_PLAN }

Functions
void	InitPlanCache (void)
void	ResetPlanCache (void)
void	ReleaseAllPlanCacheRefsInOwner (ResourceOwner owner)
CachedPlanSource *	CreateCachedPlan (struct RawStmt *raw_parse_tree, const char *query_string, CommandTag commandTag)
CachedPlanSource *	CreateCachedPlanForQuery (struct Query *analyzed_parse_tree, const char *query_string, CommandTag commandTag)
CachedPlanSource *	CreateOneShotCachedPlan (struct RawStmt *raw_parse_tree, const char *query_string, CommandTag commandTag)
void	CompleteCachedPlan (CachedPlanSource *plansource, List *querytree_list, MemoryContext querytree_context, Oid *param_types, int num_params, ParserSetupHook parserSetup, void *parserSetupArg, int cursor_options, bool fixed_result)
void	SetPostRewriteHook (CachedPlanSource *plansource, PostRewriteHook postRewrite, void *postRewriteArg)
void	SaveCachedPlan (CachedPlanSource *plansource)
void	DropCachedPlan (CachedPlanSource *plansource)
void	CachedPlanSetParentContext (CachedPlanSource *plansource, MemoryContext newcontext)
CachedPlanSource *	CopyCachedPlan (CachedPlanSource *plansource)
bool	CachedPlanIsValid (CachedPlanSource *plansource)
List *	CachedPlanGetTargetList (CachedPlanSource *plansource, QueryEnvironment *queryEnv)
CachedPlan *	GetCachedPlan (CachedPlanSource *plansource, ParamListInfo boundParams, ResourceOwner owner, QueryEnvironment *queryEnv)
PlannedStmt *	UpdateCachedPlan (CachedPlanSource *plansource, int query_index, QueryEnvironment *queryEnv)
void	ReleaseCachedPlan (CachedPlan *plan, ResourceOwner owner)
bool	CachedPlanAllowsSimpleValidityCheck (CachedPlanSource *plansource, CachedPlan *plan, ResourceOwner owner)
bool	CachedPlanIsSimplyValid (CachedPlanSource *plansource, CachedPlan *plan, ResourceOwner owner)
CachedExpression *	GetCachedExpression (Node *expr)
void	FreeCachedExpression (CachedExpression *cexpr)
static bool	CachedPlanRequiresLocking (CachedPlan *cplan)
static bool	CachedPlanValid (CachedPlan *cplan)

Variables
PGDLLIMPORT int	plan_cache_mode

Macro Definition Documentation

CACHEDEXPR_MAGIC

#define CACHEDEXPR_MAGIC   838275847

Definition at line 48 of file plancache.h.

CACHEDPLAN_MAGIC

#define CACHEDPLAN_MAGIC   953717834

Definition at line 47 of file plancache.h.

CACHEDPLANSOURCE_MAGIC

#define CACHEDPLANSOURCE_MAGIC   195726186

Definition at line 46 of file plancache.h.

Typedef Documentation

CachedExpression

typedef struct CachedExpression CachedExpression

CachedPlan

typedef struct CachedPlan CachedPlan

CachedPlanSource

typedef struct CachedPlanSource CachedPlanSource

PostRewriteHook

typedef void(* PostRewriteHook) (List *querytree_list, void *arg)

Definition at line 44 of file plancache.h.

Enumeration Type Documentation

PlanCacheMode

enum PlanCacheMode

Enumerator
PLAN_CACHE_MODE_AUTO
PLAN_CACHE_MODE_FORCE_GENERIC_PLAN
PLAN_CACHE_MODE_FORCE_CUSTOM_PLAN

Definition at line 33 of file plancache.h.

{
    PLAN_CACHE_MODE_AUTO,
    PLAN_CACHE_MODE_FORCE_GENERIC_PLAN,
    PLAN_CACHE_MODE_FORCE_CUSTOM_PLAN,
}           PlanCacheMode;

Function Documentation

CachedPlanAllowsSimpleValidityCheck()

bool CachedPlanAllowsSimpleValidityCheck	(	CachedPlanSource *	plansource,
		CachedPlan *	plan,
		ResourceOwner	owner
	)

Definition at line 1592 of file plancache.c.

{
    ListCell   *lc;
 
    /*
     * Sanity-check that the caller gave us a validated generic plan.  Notice
     * that we *don't* assert plansource->is_valid as you might expect; that's
     * because it's possible that that's already false when GetCachedPlan
     * returns, e.g. because ResetPlanCache happened partway through.  We
     * should accept the plan as long as plan->is_valid is true, and expect to
     * replan after the next CachedPlanIsSimplyValid call.
     */
    Assert(plansource->magic == CACHEDPLANSOURCE_MAGIC);
    Assert(plan->magic == CACHEDPLAN_MAGIC);
    Assert(plan->is_valid);
    Assert(plan == plansource->gplan);
    Assert(plansource->search_path != NULL);
    Assert(SearchPathMatchesCurrentEnvironment(plansource->search_path));
 
    /* We don't support oneshot plans here. */
    if (plansource->is_oneshot)
        return false;
    Assert(!plan->is_oneshot);
 
    /*
     * If the plan is dependent on RLS considerations, or it's transient,
     * reject.  These things probably can't ever happen for table-free
     * queries, but for safety's sake let's check.
     */
    if (plansource->dependsOnRLS)
        return false;
    if (plan->dependsOnRole)
        return false;
    if (TransactionIdIsValid(plan->saved_xmin))
        return false;
 
    /*
     * Reject if AcquirePlannerLocks would have anything to do.  This is
     * simplistic, but there's no need to inquire any more carefully; indeed,
     * for current callers it shouldn't even be possible to hit any of these
     * checks.
     */
    foreach(lc, plansource->query_list)
    {
        Query      *query = lfirst_node(Query, lc);
 
        if (query->commandType == CMD_UTILITY)
            return false;
        if (query->rtable || query->cteList || query->hasSubLinks)
            return false;
    }
 
    /*
     * Reject if AcquireExecutorLocks would have anything to do.  This is
     * probably unnecessary given the previous check, but let's be safe.
     */
    foreach(lc, plan->stmt_list)
    {
        PlannedStmt *plannedstmt = lfirst_node(PlannedStmt, lc);
        ListCell   *lc2;
 
        if (plannedstmt->commandType == CMD_UTILITY)
            return false;
 
        /*
         * We have to grovel through the rtable because it's likely to contain
         * an RTE_RESULT relation, rather than being totally empty.
         */
        foreach(lc2, plannedstmt->rtable)
        {
            RangeTblEntry *rte = (RangeTblEntry *) lfirst(lc2);
 
            if (rte->rtekind == RTE_RELATION)
                return false;
        }
    }
 
    /*
     * Okay, it's simple.  Note that what we've primarily established here is
     * that no locks need be taken before checking the plan's is_valid flag.
     */
 
    /* Bump refcount if requested. */
    if (owner)
    {
        ResourceOwnerEnlarge(owner);
        plan->refcount++;
        ResourceOwnerRememberPlanCacheRef(owner, plan);
    }
 
    return true;
}

References Assert(), CACHEDPLAN_MAGIC, CACHEDPLANSOURCE_MAGIC, CMD_UTILITY, Query::commandType, PlannedStmt::commandType, Query::cteList, CachedPlanSource::dependsOnRLS, CachedPlanSource::gplan, CachedPlanSource::is_oneshot, lfirst, lfirst_node, CachedPlanSource::magic, plan, CachedPlanSource::query_list, ResourceOwnerEnlarge(), ResourceOwnerRememberPlanCacheRef(), Query::rtable, PlannedStmt::rtable, RTE_RELATION, RangeTblEntry::rtekind, CachedPlanSource::search_path, SearchPathMatchesCurrentEnvironment(), and TransactionIdIsValid.

Referenced by exec_eval_simple_expr(), and exec_simple_check_plan().

CachedPlanGetTargetList()

List * CachedPlanGetTargetList	(	CachedPlanSource *	plansource,
		QueryEnvironment *	queryEnv
	)

Definition at line 1899 of file plancache.c.

{
    Query      *pstmt;
 
    /* Assert caller is doing things in a sane order */
    Assert(plansource->magic == CACHEDPLANSOURCE_MAGIC);
    Assert(plansource->is_complete);
 
    /*
     * No work needed if statement doesn't return tuples (we assume this
     * feature cannot be changed by an invalidation)
     */
    if (plansource->resultDesc == NULL)
        return NIL;
 
    /* Make sure the querytree list is valid and we have parse-time locks */
    RevalidateCachedQuery(plansource, queryEnv, true);
 
    /* Get the primary statement and find out what it returns */
    pstmt = QueryListGetPrimaryStmt(plansource->query_list);
 
    return FetchStatementTargetList((Node *) pstmt);
}

References Assert(), CACHEDPLANSOURCE_MAGIC, FetchStatementTargetList(), CachedPlanSource::is_complete, CachedPlanSource::magic, NIL, CachedPlanSource::query_list, QueryListGetPrimaryStmt(), CachedPlanSource::resultDesc, and RevalidateCachedQuery().

Referenced by exec_describe_statement_message(), and FetchPreparedStatementTargetList().

CachedPlanIsSimplyValid()

bool CachedPlanIsSimplyValid	(	CachedPlanSource *	plansource,
		CachedPlan *	plan,
		ResourceOwner	owner
	)

Definition at line 1707 of file plancache.c.

{
    /*
     * Careful here: since the caller doesn't necessarily hold a refcount on
     * the plan to start with, it's possible that "plan" is a dangling
     * pointer.  Don't dereference it until we've verified that it still
     * matches the plansource's gplan (which is either valid or NULL).
     */
    Assert(plansource->magic == CACHEDPLANSOURCE_MAGIC);
 
    /*
     * Has cache invalidation fired on this plan?  We can check this right
     * away since there are no locks that we'd need to acquire first.  Note
     * that here we *do* check plansource->is_valid, so as to force plan
     * rebuild if that's become false.
     */
    if (!plansource->is_valid ||
        plan == NULL || plan != plansource->gplan ||
        !plan->is_valid)
        return false;
 
    Assert(plan->magic == CACHEDPLAN_MAGIC);
 
    /* Is the search_path still the same as when we made it? */
    Assert(plansource->search_path != NULL);
    if (!SearchPathMatchesCurrentEnvironment(plansource->search_path))
        return false;
 
    /* It's still good.  Bump refcount if requested. */
    if (owner)
    {
        ResourceOwnerEnlarge(owner);
        plan->refcount++;
        ResourceOwnerRememberPlanCacheRef(owner, plan);
    }
 
    return true;
}

References Assert(), CACHEDPLAN_MAGIC, CACHEDPLANSOURCE_MAGIC, CachedPlanSource::gplan, CachedPlanSource::is_valid, CachedPlanSource::magic, plan, ResourceOwnerEnlarge(), ResourceOwnerRememberPlanCacheRef(), CachedPlanSource::search_path, and SearchPathMatchesCurrentEnvironment().

Referenced by exec_eval_simple_expr().

CachedPlanIsValid()

bool CachedPlanIsValid

(

CachedPlanSource *

plansource

)

Definition at line 1886 of file plancache.c.

{
    Assert(plansource->magic == CACHEDPLANSOURCE_MAGIC);
    return plansource->is_valid;
}

References Assert(), CACHEDPLANSOURCE_MAGIC, CachedPlanSource::is_valid, and CachedPlanSource::magic.

Referenced by SPI_plan_is_valid().

CachedPlanRequiresLocking()

static bool CachedPlanRequiresLocking ( CachedPlan *  cplan )

inlinestatic

Definition at line 276 of file plancache.h.

{
    return !cplan->is_oneshot && cplan->is_reused;
}

References CachedPlan::is_oneshot, and CachedPlan::is_reused.

Referenced by ExecShouldLockRelations().

CachedPlanSetParentContext()

void CachedPlanSetParentContext	(	CachedPlanSource *	plansource,
		MemoryContext	newcontext
	)

Definition at line 1754 of file plancache.c.

{
    /* Assert caller is doing things in a sane order */
    Assert(plansource->magic == CACHEDPLANSOURCE_MAGIC);
    Assert(plansource->is_complete);
 
    /* These seem worth real tests, though */
    if (plansource->is_saved)
        elog(ERROR, "cannot move a saved cached plan to another context");
    if (plansource->is_oneshot)
        elog(ERROR, "cannot move a one-shot cached plan to another context");
 
    /* OK, let the caller keep the plan where he wishes */
    MemoryContextSetParent(plansource->context, newcontext);
 
    /*
     * The query_context needs no special handling, since it's a child of
     * plansource->context.  But if there's a generic plan, it should be
     * maintained as a sibling of plansource->context.
     */
    if (plansource->gplan)
    {
        Assert(plansource->gplan->magic == CACHEDPLAN_MAGIC);
        MemoryContextSetParent(plansource->gplan->context, newcontext);
    }
}

References Assert(), CACHEDPLAN_MAGIC, CACHEDPLANSOURCE_MAGIC, CachedPlanSource::context, CachedPlan::context, elog, ERROR, CachedPlanSource::gplan, CachedPlanSource::is_complete, CachedPlanSource::is_oneshot, CachedPlanSource::is_saved, CachedPlanSource::magic, CachedPlan::magic, and MemoryContextSetParent().

Referenced by _SPI_make_plan_non_temp().

CachedPlanValid()

static bool CachedPlanValid ( CachedPlan *  cplan )

inlinestatic

Definition at line 289 of file plancache.h.

{
    return cplan->is_valid;
}

References CachedPlan::is_valid.

Referenced by ExecPlanStillValid().

CompleteCachedPlan()

void CompleteCachedPlan	(	CachedPlanSource *	plansource,
		List *	querytree_list,
		MemoryContext	querytree_context,
		Oid *	param_types,
		int	num_params,
		ParserSetupHook	parserSetup,
		void *	parserSetupArg,
		int	cursor_options,
		bool	fixed_result
	)

Definition at line 392 of file plancache.c.

{
    MemoryContext source_context = plansource->context;
    MemoryContext oldcxt = CurrentMemoryContext;
 
    /* Assert caller is doing things in a sane order */
    Assert(plansource->magic == CACHEDPLANSOURCE_MAGIC);
    Assert(!plansource->is_complete);
 
    /*
     * If caller supplied a querytree_context, reparent it underneath the
     * CachedPlanSource's context; otherwise, create a suitable context and
     * copy the querytree_list into it.  But no data copying should be done
     * for one-shot plans; for those, assume the passed querytree_list is
     * sufficiently long-lived.
     */
    if (plansource->is_oneshot)
    {
        querytree_context = CurrentMemoryContext;
    }
    else if (querytree_context != NULL)
    {
        MemoryContextSetParent(querytree_context, source_context);
        MemoryContextSwitchTo(querytree_context);
    }
    else
    {
        /* Again, it's a good bet the querytree_context can be small */
        querytree_context = AllocSetContextCreate(source_context,
                                                  "CachedPlanQuery",
                                                  ALLOCSET_START_SMALL_SIZES);
        MemoryContextSwitchTo(querytree_context);
        querytree_list = copyObject(querytree_list);
    }
 
    plansource->query_context = querytree_context;
    plansource->query_list = querytree_list;
 
    if (!plansource->is_oneshot && StmtPlanRequiresRevalidation(plansource))
    {
        /*
         * Use the planner machinery to extract dependencies.  Data is saved
         * in query_context.  (We assume that not a lot of extra cruft is
         * created by this call.)  We can skip this for one-shot plans, and
         * plans not needing revalidation have no such dependencies anyway.
         */
        extract_query_dependencies((Node *) querytree_list,
                                   &plansource->relationOids,
                                   &plansource->invalItems,
                                   &plansource->dependsOnRLS);
 
        /* Update RLS info as well. */
        plansource->rewriteRoleId = GetUserId();
        plansource->rewriteRowSecurity = row_security;
 
        /*
         * Also save the current search_path in the query_context.  (This
         * should not generate much extra cruft either, since almost certainly
         * the path is already valid.)  Again, we don't really need this for
         * one-shot plans; and we *must* skip this for transaction control
         * commands, because this could result in catalog accesses.
         */
        plansource->search_path = GetSearchPathMatcher(querytree_context);
    }
 
    /*
     * Save the final parameter types (or other parameter specification data)
     * into the source_context, as well as our other parameters.  Also save
     * the result tuple descriptor.
     */
    MemoryContextSwitchTo(source_context);
 
    if (num_params > 0)
    {
        plansource->param_types = (Oid *) palloc(num_params * sizeof(Oid));
        memcpy(plansource->param_types, param_types, num_params * sizeof(Oid));
    }
    else
        plansource->param_types = NULL;
    plansource->num_params = num_params;
    plansource->parserSetup = parserSetup;
    plansource->parserSetupArg = parserSetupArg;
    plansource->cursor_options = cursor_options;
    plansource->fixed_result = fixed_result;
    plansource->resultDesc = PlanCacheComputeResultDesc(querytree_list);
 
    MemoryContextSwitchTo(oldcxt);
 
    plansource->is_complete = true;
    plansource->is_valid = true;
}

References ALLOCSET_START_SMALL_SIZES, AllocSetContextCreate, Assert(), CACHEDPLANSOURCE_MAGIC, CachedPlanSource::context, copyObject, CurrentMemoryContext, CachedPlanSource::cursor_options, CachedPlanSource::dependsOnRLS, extract_query_dependencies(), CachedPlanSource::fixed_result, GetSearchPathMatcher(), GetUserId(), CachedPlanSource::invalItems, CachedPlanSource::is_complete, CachedPlanSource::is_oneshot, CachedPlanSource::is_valid, CachedPlanSource::magic, MemoryContextSetParent(), MemoryContextSwitchTo(), CachedPlanSource::num_params, palloc(), CachedPlanSource::param_types, CachedPlanSource::parserSetup, CachedPlanSource::parserSetupArg, PlanCacheComputeResultDesc(), CachedPlanSource::query_context, CachedPlanSource::query_list, CachedPlanSource::relationOids, CachedPlanSource::resultDesc, CachedPlanSource::rewriteRoleId, CachedPlanSource::rewriteRowSecurity, row_security, CachedPlanSource::search_path, and StmtPlanRequiresRevalidation().

Referenced by _SPI_execute_plan(), _SPI_prepare_plan(), exec_parse_message(), prepare_next_query(), and PrepareQuery().

CopyCachedPlan()

CachedPlanSource * CopyCachedPlan

(

CachedPlanSource *

plansource

)

Definition at line 1792 of file plancache.c.

{
    CachedPlanSource *newsource;
    MemoryContext source_context;
    MemoryContext querytree_context;
    MemoryContext oldcxt;
 
    Assert(plansource->magic == CACHEDPLANSOURCE_MAGIC);
    Assert(plansource->is_complete);
 
    /*
     * One-shot plans can't be copied, because we haven't taken care that
     * parsing/planning didn't scribble on the raw parse tree or querytrees.
     */
    if (plansource->is_oneshot)
        elog(ERROR, "cannot copy a one-shot cached plan");
 
    source_context = AllocSetContextCreate(CurrentMemoryContext,
                                           "CachedPlanSource",
                                           ALLOCSET_START_SMALL_SIZES);
 
    oldcxt = MemoryContextSwitchTo(source_context);
 
    newsource = (CachedPlanSource *) palloc0(sizeof(CachedPlanSource));
    newsource->magic = CACHEDPLANSOURCE_MAGIC;
    newsource->raw_parse_tree = copyObject(plansource->raw_parse_tree);
    newsource->analyzed_parse_tree = copyObject(plansource->analyzed_parse_tree);
    newsource->query_string = pstrdup(plansource->query_string);
    MemoryContextSetIdentifier(source_context, newsource->query_string);
    newsource->commandTag = plansource->commandTag;
    if (plansource->num_params > 0)
    {
        newsource->param_types = (Oid *)
            palloc(plansource->num_params * sizeof(Oid));
        memcpy(newsource->param_types, plansource->param_types,
               plansource->num_params * sizeof(Oid));
    }
    else
        newsource->param_types = NULL;
    newsource->num_params = plansource->num_params;
    newsource->parserSetup = plansource->parserSetup;
    newsource->parserSetupArg = plansource->parserSetupArg;
    newsource->postRewrite = plansource->postRewrite;
    newsource->postRewriteArg = plansource->postRewriteArg;
    newsource->cursor_options = plansource->cursor_options;
    newsource->fixed_result = plansource->fixed_result;
    if (plansource->resultDesc)
        newsource->resultDesc = CreateTupleDescCopy(plansource->resultDesc);
    else
        newsource->resultDesc = NULL;
    newsource->context = source_context;
 
    querytree_context = AllocSetContextCreate(source_context,
                                              "CachedPlanQuery",
                                              ALLOCSET_START_SMALL_SIZES);
    MemoryContextSwitchTo(querytree_context);
    newsource->query_list = copyObject(plansource->query_list);
    newsource->relationOids = copyObject(plansource->relationOids);
    newsource->invalItems = copyObject(plansource->invalItems);
    if (plansource->search_path)
        newsource->search_path = CopySearchPathMatcher(plansource->search_path);
    newsource->query_context = querytree_context;
    newsource->rewriteRoleId = plansource->rewriteRoleId;
    newsource->rewriteRowSecurity = plansource->rewriteRowSecurity;
    newsource->dependsOnRLS = plansource->dependsOnRLS;
 
    newsource->gplan = NULL;
 
    newsource->is_oneshot = false;
    newsource->is_complete = true;
    newsource->is_saved = false;
    newsource->is_valid = plansource->is_valid;
    newsource->generation = plansource->generation;
 
    /* We may as well copy any acquired cost knowledge */
    newsource->generic_cost = plansource->generic_cost;
    newsource->total_custom_cost = plansource->total_custom_cost;
    newsource->num_generic_plans = plansource->num_generic_plans;
    newsource->num_custom_plans = plansource->num_custom_plans;
 
    MemoryContextSwitchTo(oldcxt);
 
    return newsource;
}

References ALLOCSET_START_SMALL_SIZES, AllocSetContextCreate, CachedPlanSource::analyzed_parse_tree, Assert(), CACHEDPLANSOURCE_MAGIC, CachedPlanSource::commandTag, CachedPlanSource::context, copyObject, CopySearchPathMatcher(), CreateTupleDescCopy(), CurrentMemoryContext, CachedPlanSource::cursor_options, CachedPlanSource::dependsOnRLS, elog, ERROR, CachedPlanSource::fixed_result, CachedPlanSource::generation, CachedPlanSource::generic_cost, CachedPlanSource::gplan, CachedPlanSource::invalItems, CachedPlanSource::is_complete, CachedPlanSource::is_oneshot, CachedPlanSource::is_saved, CachedPlanSource::is_valid, CachedPlanSource::magic, MemoryContextSetIdentifier(), MemoryContextSwitchTo(), CachedPlanSource::num_custom_plans, CachedPlanSource::num_generic_plans, CachedPlanSource::num_params, palloc(), palloc0(), CachedPlanSource::param_types, CachedPlanSource::parserSetup, CachedPlanSource::parserSetupArg, CachedPlanSource::postRewrite, CachedPlanSource::postRewriteArg, pstrdup(), CachedPlanSource::query_context, CachedPlanSource::query_list, CachedPlanSource::query_string, CachedPlanSource::raw_parse_tree, CachedPlanSource::relationOids, CachedPlanSource::resultDesc, CachedPlanSource::rewriteRoleId, CachedPlanSource::rewriteRowSecurity, CachedPlanSource::search_path, and CachedPlanSource::total_custom_cost.

Referenced by _SPI_save_plan().

CreateCachedPlan()

CachedPlanSource * CreateCachedPlan	(	struct RawStmt *	raw_parse_tree,
		const char *	query_string,
		CommandTag	commandTag
	)

Definition at line 184 of file plancache.c.

{
    CachedPlanSource *plansource;
    MemoryContext source_context;
    MemoryContext oldcxt;
 
    Assert(query_string != NULL);   /* required as of 8.4 */
 
    /*
     * Make a dedicated memory context for the CachedPlanSource and its
     * permanent subsidiary data.  It's probably not going to be large, but
     * just in case, allow it to grow large.  Initially it's a child of the
     * caller's context (which we assume to be transient), so that it will be
     * cleaned up on error.
     */
    source_context = AllocSetContextCreate(CurrentMemoryContext,
                                           "CachedPlanSource",
                                           ALLOCSET_START_SMALL_SIZES);
 
    /*
     * Create and fill the CachedPlanSource struct within the new context.
     * Most fields are just left empty for the moment.
     */
    oldcxt = MemoryContextSwitchTo(source_context);
 
    plansource = (CachedPlanSource *) palloc0(sizeof(CachedPlanSource));
    plansource->magic = CACHEDPLANSOURCE_MAGIC;
    plansource->raw_parse_tree = copyObject(raw_parse_tree);
    plansource->analyzed_parse_tree = NULL;
    plansource->query_string = pstrdup(query_string);
    MemoryContextSetIdentifier(source_context, plansource->query_string);
    plansource->commandTag = commandTag;
    plansource->param_types = NULL;
    plansource->num_params = 0;
    plansource->parserSetup = NULL;
    plansource->parserSetupArg = NULL;
    plansource->postRewrite = NULL;
    plansource->postRewriteArg = NULL;
    plansource->cursor_options = 0;
    plansource->fixed_result = false;
    plansource->resultDesc = NULL;
    plansource->context = source_context;
    plansource->query_list = NIL;
    plansource->relationOids = NIL;
    plansource->invalItems = NIL;
    plansource->search_path = NULL;
    plansource->query_context = NULL;
    plansource->rewriteRoleId = InvalidOid;
    plansource->rewriteRowSecurity = false;
    plansource->dependsOnRLS = false;
    plansource->gplan = NULL;
    plansource->is_oneshot = false;
    plansource->is_complete = false;
    plansource->is_saved = false;
    plansource->is_valid = false;
    plansource->generation = 0;
    plansource->generic_cost = -1;
    plansource->total_custom_cost = 0;
    plansource->num_generic_plans = 0;
    plansource->num_custom_plans = 0;
 
    MemoryContextSwitchTo(oldcxt);
 
    return plansource;
}

References ALLOCSET_START_SMALL_SIZES, AllocSetContextCreate, CachedPlanSource::analyzed_parse_tree, Assert(), CACHEDPLANSOURCE_MAGIC, CachedPlanSource::commandTag, CachedPlanSource::context, copyObject, CurrentMemoryContext, CachedPlanSource::cursor_options, CachedPlanSource::dependsOnRLS, CachedPlanSource::fixed_result, CachedPlanSource::generation, CachedPlanSource::generic_cost, CachedPlanSource::gplan, InvalidOid, CachedPlanSource::invalItems, CachedPlanSource::is_complete, CachedPlanSource::is_oneshot, CachedPlanSource::is_saved, CachedPlanSource::is_valid, CachedPlanSource::magic, MemoryContextSetIdentifier(), MemoryContextSwitchTo(), NIL, CachedPlanSource::num_custom_plans, CachedPlanSource::num_generic_plans, CachedPlanSource::num_params, palloc0(), CachedPlanSource::param_types, CachedPlanSource::parserSetup, CachedPlanSource::parserSetupArg, CachedPlanSource::postRewrite, CachedPlanSource::postRewriteArg, pstrdup(), CachedPlanSource::query_context, CachedPlanSource::query_list, CachedPlanSource::query_string, CachedPlanSource::raw_parse_tree, CachedPlanSource::relationOids, CachedPlanSource::resultDesc, CachedPlanSource::rewriteRoleId, CachedPlanSource::rewriteRowSecurity, CachedPlanSource::search_path, and CachedPlanSource::total_custom_cost.

Referenced by _SPI_prepare_plan(), CreateCachedPlanForQuery(), exec_parse_message(), prepare_next_query(), and PrepareQuery().

CreateCachedPlanForQuery()

CachedPlanSource * CreateCachedPlanForQuery	(	struct Query *	analyzed_parse_tree,
		const char *	query_string,
		CommandTag	commandTag
	)

Definition at line 264 of file plancache.c.

{
    CachedPlanSource *plansource;
    MemoryContext oldcxt;
 
    /* Rather than duplicating CreateCachedPlan, just do this: */
    plansource = CreateCachedPlan(NULL, query_string, commandTag);
    oldcxt = MemoryContextSwitchTo(plansource->context);
    plansource->analyzed_parse_tree = copyObject(analyzed_parse_tree);
    MemoryContextSwitchTo(oldcxt);
 
    return plansource;
}

References CachedPlanSource::analyzed_parse_tree, CachedPlanSource::context, copyObject, CreateCachedPlan(), and MemoryContextSwitchTo().

Referenced by prepare_next_query().

CreateOneShotCachedPlan()

CachedPlanSource * CreateOneShotCachedPlan	(	struct RawStmt *	raw_parse_tree,
		const char *	query_string,
		CommandTag	commandTag
	)

Definition at line 299 of file plancache.c.

{
    CachedPlanSource *plansource;
 
    Assert(query_string != NULL);   /* required as of 8.4 */
 
    /*
     * Create and fill the CachedPlanSource struct within the caller's memory
     * context.  Most fields are just left empty for the moment.
     */
    plansource = (CachedPlanSource *) palloc0(sizeof(CachedPlanSource));
    plansource->magic = CACHEDPLANSOURCE_MAGIC;
    plansource->raw_parse_tree = raw_parse_tree;
    plansource->analyzed_parse_tree = NULL;
    plansource->query_string = query_string;
    plansource->commandTag = commandTag;
    plansource->param_types = NULL;
    plansource->num_params = 0;
    plansource->parserSetup = NULL;
    plansource->parserSetupArg = NULL;
    plansource->postRewrite = NULL;
    plansource->postRewriteArg = NULL;
    plansource->cursor_options = 0;
    plansource->fixed_result = false;
    plansource->resultDesc = NULL;
    plansource->context = CurrentMemoryContext;
    plansource->query_list = NIL;
    plansource->relationOids = NIL;
    plansource->invalItems = NIL;
    plansource->search_path = NULL;
    plansource->query_context = NULL;
    plansource->rewriteRoleId = InvalidOid;
    plansource->rewriteRowSecurity = false;
    plansource->dependsOnRLS = false;
    plansource->gplan = NULL;
    plansource->is_oneshot = true;
    plansource->is_complete = false;
    plansource->is_saved = false;
    plansource->is_valid = false;
    plansource->generation = 0;
    plansource->generic_cost = -1;
    plansource->total_custom_cost = 0;
    plansource->num_generic_plans = 0;
    plansource->num_custom_plans = 0;
 
    return plansource;
}

References CachedPlanSource::analyzed_parse_tree, Assert(), CACHEDPLANSOURCE_MAGIC, CachedPlanSource::commandTag, CachedPlanSource::context, CurrentMemoryContext, CachedPlanSource::cursor_options, CachedPlanSource::dependsOnRLS, CachedPlanSource::fixed_result, CachedPlanSource::generation, CachedPlanSource::generic_cost, CachedPlanSource::gplan, InvalidOid, CachedPlanSource::invalItems, CachedPlanSource::is_complete, CachedPlanSource::is_oneshot, CachedPlanSource::is_saved, CachedPlanSource::is_valid, CachedPlanSource::magic, NIL, CachedPlanSource::num_custom_plans, CachedPlanSource::num_generic_plans, CachedPlanSource::num_params, palloc0(), CachedPlanSource::param_types, CachedPlanSource::parserSetup, CachedPlanSource::parserSetupArg, CachedPlanSource::postRewrite, CachedPlanSource::postRewriteArg, CachedPlanSource::query_context, CachedPlanSource::query_list, CachedPlanSource::query_string, CachedPlanSource::raw_parse_tree, CachedPlanSource::relationOids, CachedPlanSource::resultDesc, CachedPlanSource::rewriteRoleId, CachedPlanSource::rewriteRowSecurity, CachedPlanSource::search_path, and CachedPlanSource::total_custom_cost.

Referenced by _SPI_prepare_oneshot_plan().

DropCachedPlan()

void DropCachedPlan

(

CachedPlanSource *

plansource

)

Definition at line 575 of file plancache.c.

{
    Assert(plansource->magic == CACHEDPLANSOURCE_MAGIC);
 
    /* If it's been saved, remove it from the list */
    if (plansource->is_saved)
    {
        dlist_delete(&plansource->node);
        plansource->is_saved = false;
    }
 
    /* Decrement generic CachedPlan's refcount and drop if no longer needed */
    ReleaseGenericPlan(plansource);
 
    /* Mark it no longer valid */
    plansource->magic = 0;
 
    /*
     * Remove the CachedPlanSource and all subsidiary data (including the
     * query_context if any).  But if it's a one-shot we can't free anything.
     */
    if (!plansource->is_oneshot)
        MemoryContextDelete(plansource->context);
}

References Assert(), CACHEDPLANSOURCE_MAGIC, CachedPlanSource::context, dlist_delete(), CachedPlanSource::is_oneshot, CachedPlanSource::is_saved, CachedPlanSource::magic, MemoryContextDelete(), CachedPlanSource::node, and ReleaseGenericPlan().

Referenced by drop_unnamed_stmt(), DropAllPreparedStatements(), DropPreparedStatement(), SPI_freeplan(), and sql_delete_callback().

FreeCachedExpression()

void FreeCachedExpression

(

CachedExpression *

cexpr

)

Definition at line 1993 of file plancache.c.

{
    /* Sanity check */
    Assert(cexpr->magic == CACHEDEXPR_MAGIC);
    /* Unlink from global list */
    dlist_delete(&cexpr->node);
    /* Free all storage associated with CachedExpression */
    MemoryContextDelete(cexpr->context);
}

References Assert(), CACHEDEXPR_MAGIC, CachedExpression::context, dlist_delete(), CachedExpression::magic, MemoryContextDelete(), and CachedExpression::node.

Referenced by get_cast_hashentry().

GetCachedExpression()

CachedExpression * GetCachedExpression

(

Node *

expr

)

Definition at line 1936 of file plancache.c.

{
    CachedExpression *cexpr;
    List       *relationOids;
    List       *invalItems;
    MemoryContext cexpr_context;
    MemoryContext oldcxt;
 
    /*
     * Pass the expression through the planner, and collect dependencies.
     * Everything built here is leaked in the caller's context; that's
     * intentional to minimize the size of the permanent data structure.
     */
    expr = (Node *) expression_planner_with_deps((Expr *) expr,
                                                 &relationOids,
                                                 &invalItems);
 
    /*
     * Make a private memory context, and copy what we need into that.  To
     * avoid leaking a long-lived context if we fail while copying data, we
     * initially make the context under the caller's context.
     */
    cexpr_context = AllocSetContextCreate(CurrentMemoryContext,
                                          "CachedExpression",
                                          ALLOCSET_SMALL_SIZES);
 
    oldcxt = MemoryContextSwitchTo(cexpr_context);
 
    cexpr = (CachedExpression *) palloc(sizeof(CachedExpression));
    cexpr->magic = CACHEDEXPR_MAGIC;
    cexpr->expr = copyObject(expr);
    cexpr->is_valid = true;
    cexpr->relationOids = copyObject(relationOids);
    cexpr->invalItems = copyObject(invalItems);
    cexpr->context = cexpr_context;
 
    MemoryContextSwitchTo(oldcxt);
 
    /*
     * Reparent the expr's memory context under CacheMemoryContext so that it
     * will live indefinitely.
     */
    MemoryContextSetParent(cexpr_context, CacheMemoryContext);
 
    /*
     * Add the entry to the global list of cached expressions.
     */
    dlist_push_tail(&cached_expression_list, &cexpr->node);
 
    return cexpr;
}

References ALLOCSET_SMALL_SIZES, AllocSetContextCreate, cached_expression_list, CACHEDEXPR_MAGIC, CacheMemoryContext, CachedExpression::context, copyObject, CurrentMemoryContext, dlist_push_tail(), CachedExpression::expr, expression_planner_with_deps(), CachedExpression::invalItems, CachedExpression::is_valid, CachedExpression::magic, MemoryContextSetParent(), MemoryContextSwitchTo(), CachedExpression::node, palloc(), and CachedExpression::relationOids.

Referenced by get_cast_hashentry().

GetCachedPlan()

CachedPlan * GetCachedPlan	(	CachedPlanSource *	plansource,
		ParamListInfo	boundParams,
		ResourceOwner	owner,
		QueryEnvironment *	queryEnv
	)

Definition at line 1422 of file plancache.c.

{
    CachedPlan *plan = NULL;
    List       *qlist;
    bool        customplan;
 
    /* Assert caller is doing things in a sane order */
    Assert(plansource->magic == CACHEDPLANSOURCE_MAGIC);
    Assert(plansource->is_complete);
    /* This seems worth a real test, though */
    if (owner && !plansource->is_saved)
        elog(ERROR, "cannot apply ResourceOwner to non-saved cached plan");
 
    /* Make sure the querytree list is valid and we have parse-time locks */
    qlist = RevalidateCachedQuery(plansource, queryEnv, true);
 
    /* Decide whether to use a custom plan */
    customplan = choose_custom_plan(plansource, boundParams);
 
    if (!customplan)
    {
        if (CheckCachedPlan(plansource))
        {
            /* We want a generic plan, and we already have a valid one */
            plan = plansource->gplan;
            Assert(plan->magic == CACHEDPLAN_MAGIC);
            /* Reusing the existing plan, so not all locks may be acquired. */
            plan->is_reused = true;
        }
        else
        {
            /* Build a new generic plan */
            plan = BuildCachedPlan(plansource, qlist, NULL, queryEnv);
            /* Just make real sure plansource->gplan is clear */
            ReleaseGenericPlan(plansource);
            /* Link the new generic plan into the plansource */
            plansource->gplan = plan;
            plan->refcount++;
            /* Immediately reparent into appropriate context */
            if (plansource->is_saved)
            {
                /* saved plans all live under CacheMemoryContext */
                MemoryContextSetParent(plan->context, CacheMemoryContext);
                plan->is_saved = true;
            }
            else
            {
                /* otherwise, it should be a sibling of the plansource */
                MemoryContextSetParent(plan->context,
                                       MemoryContextGetParent(plansource->context));
            }
            /* Update generic_cost whenever we make a new generic plan */
            plansource->generic_cost = cached_plan_cost(plan, false);
 
            /*
             * If, based on the now-known value of generic_cost, we'd not have
             * chosen to use a generic plan, then forget it and make a custom
             * plan.  This is a bit of a wart but is necessary to avoid a
             * glitch in behavior when the custom plans are consistently big
             * winners; at some point we'll experiment with a generic plan and
             * find it's a loser, but we don't want to actually execute that
             * plan.
             */
            customplan = choose_custom_plan(plansource, boundParams);
 
            /*
             * If we choose to plan again, we need to re-copy the query_list,
             * since the planner probably scribbled on it.  We can force
             * BuildCachedPlan to do that by passing NIL.
             */
            qlist = NIL;
        }
    }
 
    if (customplan)
    {
        /* Build a custom plan */
        plan = BuildCachedPlan(plansource, qlist, boundParams, queryEnv);
        /* Accumulate total costs of custom plans */
        plansource->total_custom_cost += cached_plan_cost(plan, true);
 
        plansource->num_custom_plans++;
    }
    else
    {
        plansource->num_generic_plans++;
    }
 
    Assert(plan != NULL);
 
    /* Flag the plan as in use by caller */
    if (owner)
        ResourceOwnerEnlarge(owner);
    plan->refcount++;
    if (owner)
        ResourceOwnerRememberPlanCacheRef(owner, plan);
 
    /*
     * Saved plans should be under CacheMemoryContext so they will not go away
     * until their reference count goes to zero.  In the generic-plan cases we
     * already took care of that, but for a custom plan, do it as soon as we
     * have created a reference-counted link.
     */
    if (customplan && plansource->is_saved)
    {
        MemoryContextSetParent(plan->context, CacheMemoryContext);
        plan->is_saved = true;
    }
 
    return plan;
}

References Assert(), BuildCachedPlan(), cached_plan_cost(), CACHEDPLAN_MAGIC, CACHEDPLANSOURCE_MAGIC, CacheMemoryContext, CheckCachedPlan(), choose_custom_plan(), CachedPlanSource::context, elog, ERROR, CachedPlanSource::generic_cost, CachedPlanSource::gplan, CachedPlanSource::is_complete, CachedPlanSource::is_saved, CachedPlanSource::magic, MemoryContextGetParent(), MemoryContextSetParent(), NIL, CachedPlanSource::num_custom_plans, CachedPlanSource::num_generic_plans, plan, ReleaseGenericPlan(), ResourceOwnerEnlarge(), ResourceOwnerRememberPlanCacheRef(), RevalidateCachedQuery(), and CachedPlanSource::total_custom_cost.

Referenced by _SPI_execute_plan(), exec_bind_message(), ExecuteQuery(), ExplainExecuteQuery(), init_execution_state(), SPI_cursor_open_internal(), and SPI_plan_get_cached_plan().

InitPlanCache()

void InitPlanCache

(

void

)

Definition at line 147 of file plancache.c.

{
    CacheRegisterRelcacheCallback(PlanCacheRelCallback, (Datum) 0);
    CacheRegisterSyscacheCallback(PROCOID, PlanCacheObjectCallback, (Datum) 0);
    CacheRegisterSyscacheCallback(TYPEOID, PlanCacheObjectCallback, (Datum) 0);
    CacheRegisterSyscacheCallback(NAMESPACEOID, PlanCacheSysCallback, (Datum) 0);
    CacheRegisterSyscacheCallback(OPEROID, PlanCacheSysCallback, (Datum) 0);
    CacheRegisterSyscacheCallback(AMOPOPID, PlanCacheSysCallback, (Datum) 0);
    CacheRegisterSyscacheCallback(FOREIGNSERVEROID, PlanCacheSysCallback, (Datum) 0);
    CacheRegisterSyscacheCallback(FOREIGNDATAWRAPPEROID, PlanCacheSysCallback, (Datum) 0);
}

References CacheRegisterRelcacheCallback(), CacheRegisterSyscacheCallback(), PlanCacheObjectCallback(), PlanCacheRelCallback(), and PlanCacheSysCallback().

Referenced by InitPostgres().

ReleaseAllPlanCacheRefsInOwner()

void ReleaseAllPlanCacheRefsInOwner

(

ResourceOwner

owner

)

Definition at line 2494 of file plancache.c.

{
    ResourceOwnerReleaseAllOfKind(owner, &planref_resowner_desc);
}

References planref_resowner_desc, and ResourceOwnerReleaseAllOfKind().

Referenced by plpgsql_call_handler(), plpgsql_inline_handler(), and plpgsql_xact_cb().

ReleaseCachedPlan()

void ReleaseCachedPlan	(	CachedPlan *	plan,
		ResourceOwner	owner
	)

Definition at line 1547 of file plancache.c.

{
    Assert(plan->magic == CACHEDPLAN_MAGIC);
    if (owner)
    {
        Assert(plan->is_saved);
        ResourceOwnerForgetPlanCacheRef(owner, plan);
    }
    Assert(plan->refcount > 0);
    plan->refcount--;
    if (plan->refcount == 0)
    {
        /* Mark it no longer valid */
        plan->magic = 0;
 
        /* One-shot plans do not own their context, so we can't free them */
        if (!plan->is_oneshot)
            MemoryContextDelete(plan->context);
    }
}

References Assert(), CACHEDPLAN_MAGIC, MemoryContextDelete(), plan, and ResourceOwnerForgetPlanCacheRef().

Referenced by _SPI_execute_plan(), exec_eval_simple_expr(), exec_simple_check_plan(), ExplainExecuteQuery(), init_execution_state(), make_callstmt_target(), PortalReleaseCachedPlan(), ReleaseGenericPlan(), ResOwnerReleaseCachedPlan(), ShutdownSQLFunction(), and SPI_cursor_open_internal().

ResetPlanCache()

void ResetPlanCache

(

void

)

Definition at line 2447 of file plancache.c.

{
    dlist_iter  iter;
 
    dlist_foreach(iter, &saved_plan_list)
    {
        CachedPlanSource *plansource = dlist_container(CachedPlanSource,
                                                       node, iter.cur);
 
        Assert(plansource->magic == CACHEDPLANSOURCE_MAGIC);
 
        /* No work if it's already invalidated */
        if (!plansource->is_valid)
            continue;
 
        /*
         * We *must not* mark transaction control statements as invalid,
         * particularly not ROLLBACK, because they may need to be executed in
         * aborted transactions when we can't revalidate them (cf bug #5269).
         * In general there's no point in invalidating statements for which a
         * new parse analysis/rewrite/plan cycle would certainly give the same
         * results.
         */
        if (!StmtPlanRequiresRevalidation(plansource))
            continue;
 
        plansource->is_valid = false;
        if (plansource->gplan)
            plansource->gplan->is_valid = false;
    }
 
    /* Likewise invalidate cached expressions */
    dlist_foreach(iter, &cached_expression_list)
    {
        CachedExpression *cexpr = dlist_container(CachedExpression,
                                                  node, iter.cur);
 
        Assert(cexpr->magic == CACHEDEXPR_MAGIC);
 
        cexpr->is_valid = false;
    }
}

References Assert(), cached_expression_list, CACHEDEXPR_MAGIC, CACHEDPLANSOURCE_MAGIC, dlist_iter::cur, dlist_container, dlist_foreach, CachedPlanSource::gplan, CachedPlanSource::is_valid, CachedPlan::is_valid, CachedExpression::is_valid, CachedPlanSource::magic, CachedExpression::magic, saved_plan_list, and StmtPlanRequiresRevalidation().

Referenced by assign_session_replication_role(), DiscardAll(), DiscardCommand(), and PlanCacheSysCallback().

SaveCachedPlan()

void SaveCachedPlan

(

CachedPlanSource *

plansource

)

Definition at line 531 of file plancache.c.

{
    /* Assert caller is doing things in a sane order */
    Assert(plansource->magic == CACHEDPLANSOURCE_MAGIC);
    Assert(plansource->is_complete);
    Assert(!plansource->is_saved);
 
    /* This seems worth a real test, though */
    if (plansource->is_oneshot)
        elog(ERROR, "cannot save one-shot cached plan");
 
    /*
     * In typical use, this function would be called before generating any
     * plans from the CachedPlanSource.  If there is a generic plan, moving it
     * into CacheMemoryContext would be pretty risky since it's unclear
     * whether the caller has taken suitable care with making references
     * long-lived.  Best thing to do seems to be to discard the plan.
     */
    ReleaseGenericPlan(plansource);
 
    /*
     * Reparent the source memory context under CacheMemoryContext so that it
     * will live indefinitely.  The query_context follows along since it's
     * already a child of the other one.
     */
    MemoryContextSetParent(plansource->context, CacheMemoryContext);
 
    /*
     * Add the entry to the global list of cached plans.
     */
    dlist_push_tail(&saved_plan_list, &plansource->node);
 
    plansource->is_saved = true;
}

References Assert(), CACHEDPLANSOURCE_MAGIC, CacheMemoryContext, CachedPlanSource::context, dlist_push_tail(), elog, ERROR, CachedPlanSource::is_complete, CachedPlanSource::is_oneshot, CachedPlanSource::is_saved, CachedPlanSource::magic, MemoryContextSetParent(), CachedPlanSource::node, ReleaseGenericPlan(), and saved_plan_list.

Referenced by _SPI_save_plan(), exec_parse_message(), prepare_next_query(), SPI_keepplan(), and StorePreparedStatement().

SetPostRewriteHook()

void SetPostRewriteHook	(	CachedPlanSource *	plansource,
		PostRewriteHook	postRewrite,
		void *	postRewriteArg
	)

Definition at line 506 of file plancache.c.

{
    Assert(plansource->magic == CACHEDPLANSOURCE_MAGIC);
    plansource->postRewrite = postRewrite;
    plansource->postRewriteArg = postRewriteArg;
}

References Assert(), CACHEDPLANSOURCE_MAGIC, CachedPlanSource::magic, CachedPlanSource::postRewrite, and CachedPlanSource::postRewriteArg.

Referenced by prepare_next_query().

UpdateCachedPlan()

PlannedStmt * UpdateCachedPlan	(	CachedPlanSource *	plansource,
		int	query_index,
		QueryEnvironment *	queryEnv
	)

Definition at line 1205 of file plancache.c.

{
    List       *query_list = plansource->query_list,
               *plan_list;
    ListCell   *l1,
               *l2;
    CachedPlan *plan = plansource->gplan;
    MemoryContext oldcxt;
 
    Assert(ActiveSnapshotSet());
 
    /* Sanity checks (XXX can be Asserts?) */
    if (plan == NULL)
        elog(ERROR, "UpdateCachedPlan() called in the wrong context: plansource->gplan is NULL");
    else if (plan->is_valid)
        elog(ERROR, "UpdateCachedPlan() called in the wrong context: plansource->gplan->is_valid is true");
    else if (plan->is_oneshot)
        elog(ERROR, "UpdateCachedPlan() called in the wrong context: plansource->gplan->is_oneshot is true");
 
    /*
     * The plansource might have become invalid since GetCachedPlan() returned
     * the CachedPlan. See the comment in BuildCachedPlan() for details on why
     * this might happen.  Although invalidation is likely a false positive as
     * stated there, we make the plan valid to ensure the query list used for
     * planning is up to date.
     *
     * The risk of catching an invalidation is higher here than when
     * BuildCachedPlan() is called from GetCachedPlan(), because this function
     * is normally called long after GetCachedPlan() returns the CachedPlan,
     * so much more processing could have occurred including things that mark
     * the CachedPlanSource invalid.
     *
     * Note: Do not release plansource->gplan, because the upstream callers
     * (such as the callers of ExecutorStartCachedPlan()) would still be
     * referencing it.
     */
    if (!plansource->is_valid)
        query_list = RevalidateCachedQuery(plansource, queryEnv, false);
    Assert(query_list != NIL);
 
    /*
     * Build a new generic plan for all the queries after making a copy to be
     * scribbled on by the planner.
     */
    query_list = copyObject(query_list);
 
    /*
     * Planning work is done in the caller's memory context.  The resulting
     * PlannedStmt is then copied into plan->stmt_context after throwing away
     * the old ones.
     */
    plan_list = pg_plan_queries(query_list, plansource->query_string,
                                plansource->cursor_options, NULL);
    Assert(list_length(plan_list) == list_length(plan->stmt_list));
 
    MemoryContextReset(plan->stmt_context);
    oldcxt = MemoryContextSwitchTo(plan->stmt_context);
    forboth(l1, plan_list, l2, plan->stmt_list)
    {
        PlannedStmt *plannedstmt = lfirst(l1);
 
        lfirst(l2) = copyObject(plannedstmt);
    }
    MemoryContextSwitchTo(oldcxt);
 
    /*
     * XXX Should this also (re)set the properties of the CachedPlan that are
     * set in BuildCachedPlan() after creating the fresh plans such as
     * planRoleId, dependsOnRole, and saved_xmin?
     */
 
    /*
     * We've updated all the plans that might have been invalidated, so mark
     * the CachedPlan as valid.
     */
    plan->is_valid = true;
 
    /* Also update generic_cost because we just created a new generic plan. */
    plansource->generic_cost = cached_plan_cost(plan, false);
 
    return list_nth_node(PlannedStmt, plan->stmt_list, query_index);
}

References ActiveSnapshotSet(), Assert(), cached_plan_cost(), copyObject, CachedPlanSource::cursor_options, elog, ERROR, forboth, CachedPlanSource::generic_cost, CachedPlanSource::gplan, CachedPlanSource::is_valid, lfirst, list_length(), list_nth_node, MemoryContextReset(), MemoryContextSwitchTo(), NIL, pg_plan_queries(), plan, CachedPlanSource::query_list, CachedPlanSource::query_string, and RevalidateCachedQuery().

Referenced by ExecutorStartCachedPlan().

Variable Documentation

plan_cache_mode

PGDLLIMPORT int plan_cache_mode

extern

Definition at line 139 of file plancache.c.

Referenced by choose_custom_plan().