From a34fa8ee7cc757671632dc4dcae4f21e8f2e2357 Mon Sep 17 00:00:00 2001 From: Tom Lane Date: Thu, 20 Nov 2014 18:36:07 -0500 Subject: [PATCH] Initial code review for CustomScan patch. Get rid of the pernicious entanglement between planner and executor headers introduced by commit 0b03e5951bf0a1a8868db13f02049cf686a82165. Also, rearrange the CustomFoo struct/typedef definitions so that all the typedef names are seen as used by the compiler. Without this pgindent will mess things up a bit, which is not so important perhaps, but it also removes a bizarre discrepancy between the declaration arrangement used for CustomExecMethods and that used for CustomScanMethods and CustomPathMethods. Clean up the commentary around ExecSupportsMarkRestore to reflect the rather large change in its API. Const-ify register_custom_path_provider's argument. This necessitates casting away const in the function, but that seems better than forcing callers of the function to do so (or else not const-ify their method pointer structs, which was sort of the whole point). De-export fix_expr_common. I don't like the exporting of fix_scan_expr or replace_nestloop_params either, but this one surely has got little excuse. --- src/backend/executor/execAmi.c | 44 ++++++----- src/backend/optimizer/plan/createplan.c | 97 +++++++++++++------------ src/backend/optimizer/plan/setrefs.c | 13 ++-- src/backend/optimizer/util/pathnode.c | 15 ++-- src/include/executor/executor.h | 5 +- src/include/executor/nodeCustom.h | 6 +- src/include/nodes/execnodes.h | 55 +++++++------- src/include/nodes/plannodes.h | 44 +++++------ src/include/nodes/relation.h | 38 +++++----- src/include/optimizer/pathnode.h | 6 +- src/include/optimizer/planmain.h | 3 +- 11 files changed, 167 insertions(+), 159 deletions(-) diff --git a/src/backend/executor/execAmi.c b/src/backend/executor/execAmi.c index b14e08cd1af..643aaace3a9 100644 --- a/src/backend/executor/execAmi.c +++ b/src/backend/executor/execAmi.c @@ -381,11 +381,14 @@ ExecRestrPos(PlanState *node) } /* - * ExecSupportsMarkRestore - does a plan type support mark/restore? + * ExecSupportsMarkRestore - does a Path support mark/restore? + * + * This is used during planning and so must accept a Path, not a Plan. + * We keep it here to be adjacent to the routines above, which also must + * know which plan types support mark/restore. * * XXX Ideally, all plan node types would support mark/restore, and this * wouldn't be needed. For now, this had better match the routines above. - * But note the test is on Plan nodetype, not PlanState nodetype. * * (However, since the only present use of mark/restore is in mergejoin, * there is no need to support mark/restore in any plan type that is not @@ -395,6 +398,11 @@ ExecRestrPos(PlanState *node) bool ExecSupportsMarkRestore(Path *pathnode) { + /* + * For consistency with the routines above, we do not examine the nodeTag + * but rather the pathtype, which is the Plan node type the Path would + * produce. + */ switch (pathnode->pathtype) { case T_SeqScan: @@ -406,27 +414,23 @@ ExecSupportsMarkRestore(Path *pathnode) case T_Sort: return true; + case T_CustomScan: + Assert(IsA(pathnode, CustomPath)); + if (((CustomPath *) pathnode)->flags & CUSTOMPATH_SUPPORT_MARK_RESTORE) + return true; + return false; + case T_Result: /* - * T_Result only supports mark/restore if it has a child plan that - * does, so we do not have enough information to give a really - * correct answer. However, for current uses it's enough to - * always say "false", because this routine is not asked about - * gating Result plans, only base-case Results. + * Although Result supports mark/restore if it has a child plan + * that does, we presently come here only for ResultPath nodes, + * which represent Result plans without a child plan. So there is + * nothing to recurse to and we can just say "false". */ + Assert(IsA(pathnode, ResultPath)); return false; - case T_CustomScan: - { - CustomPath *cpath = (CustomPath *) pathnode; - - Assert(IsA(cpath, CustomPath)); - if (cpath->flags & CUSTOMPATH_SUPPORT_MARK_RESTORE) - return true; - } - break; - default: break; } @@ -491,10 +495,10 @@ ExecSupportsBackwardScan(Plan *node) case T_CustomScan: { - uint32 flags = ((CustomScan *) node)->flags; + uint32 flags = ((CustomScan *) node)->flags; - if (TargetListSupportsBackwardScan(node->targetlist) && - (flags & CUSTOMPATH_SUPPORT_BACKWARD_SCAN) != 0) + if ((flags & CUSTOMPATH_SUPPORT_BACKWARD_SCAN) && + TargetListSupportsBackwardScan(node->targetlist)) return true; } return false; diff --git a/src/backend/optimizer/plan/createplan.c b/src/backend/optimizer/plan/createplan.c index 0a85cd99061..e6bd4c326ca 100644 --- a/src/backend/optimizer/plan/createplan.c +++ b/src/backend/optimizer/plan/createplan.c @@ -78,8 +78,8 @@ static WorkTableScan *create_worktablescan_plan(PlannerInfo *root, Path *best_pa static ForeignScan *create_foreignscan_plan(PlannerInfo *root, ForeignPath *best_path, List *tlist, List *scan_clauses); static Plan *create_customscan_plan(PlannerInfo *root, - CustomPath *best_path, - List *tlist, List *scan_clauses); + CustomPath *best_path, + List *tlist, List *scan_clauses); static NestLoop *create_nestloop_plan(PlannerInfo *root, NestPath *best_path, Plan *outer_plan, Plan *inner_plan); static MergeJoin *create_mergejoin_plan(PlannerInfo *root, MergePath *best_path, @@ -1083,52 +1083,6 @@ create_unique_plan(PlannerInfo *root, UniquePath *best_path) return plan; } -/* - * create_custom_plan - * - * Transform a CustomPath into a Plan. - */ -static Plan * -create_customscan_plan(PlannerInfo *root, CustomPath *best_path, - List *tlist, List *scan_clauses) -{ - Plan *plan; - RelOptInfo *rel = best_path->path.parent; - - /* - * Right now, all we can support is CustomScan node which is associated - * with a particular base relation to be scanned. - */ - Assert(rel && rel->reloptkind == RELOPT_BASEREL); - - /* - * Sort clauses into the best execution order, although custom-scan - * provider can reorder them again. - */ - scan_clauses = order_qual_clauses(root, scan_clauses); - - /* - * Create a CustomScan (or its inheritance) node according to - * the supplied CustomPath. - */ - plan = best_path->methods->PlanCustomPath(root, rel, best_path, tlist, - scan_clauses); - - /* - * NOTE: unlike create_foreignscan_plan(), it is responsibility of - * the custom plan provider to replace outer-relation variables - * with nestloop params, because we cannot know how many expression - * trees are held in the private fields. - */ - - /* - * Copy cost data from Path to Plan; no need to make custom-plan - * providers do this - */ - copy_path_costsize(plan, &best_path->path); - - return plan; -} /***************************************************************************** * @@ -2063,6 +2017,53 @@ create_foreignscan_plan(PlannerInfo *root, ForeignPath *best_path, return scan_plan; } +/* + * create_custom_plan + * + * Transform a CustomPath into a Plan. + */ +static Plan * +create_customscan_plan(PlannerInfo *root, CustomPath *best_path, + List *tlist, List *scan_clauses) +{ + Plan *plan; + RelOptInfo *rel = best_path->path.parent; + + /* + * Right now, all we can support is CustomScan node which is associated + * with a particular base relation to be scanned. + */ + Assert(rel && rel->reloptkind == RELOPT_BASEREL); + + /* + * Sort clauses into the best execution order, although custom-scan + * provider can reorder them again. + */ + scan_clauses = order_qual_clauses(root, scan_clauses); + + /* + * Invoke custom plan provider to create the Plan node represented by the + * CustomPath. + */ + plan = best_path->methods->PlanCustomPath(root, rel, best_path, tlist, + scan_clauses); + + /* + * NOTE: unlike create_foreignscan_plan(), it is the responsibility of the + * custom plan provider to replace outer-relation variables with nestloop + * params, because we cannot know what expression trees may be held in + * private fields. + */ + + /* + * Copy cost data from Path to Plan; no need to make custom-plan providers + * do this + */ + copy_path_costsize(plan, &best_path->path); + + return plan; +} + /***************************************************************************** * diff --git a/src/backend/optimizer/plan/setrefs.c b/src/backend/optimizer/plan/setrefs.c index bbc68a05a6c..e42972750b9 100644 --- a/src/backend/optimizer/plan/setrefs.c +++ b/src/backend/optimizer/plan/setrefs.c @@ -587,12 +587,13 @@ set_plan_refs(PlannerInfo *root, Plan *plan, int rtoffset) fix_scan_list(root, cscan->scan.plan.targetlist, rtoffset); cscan->scan.plan.qual = fix_scan_list(root, cscan->scan.plan.qual, rtoffset); + /* - * The core implementation applies the routine to fixup - * varno on the target-list and scan qualifier. - * If custom-scan has additional expression nodes on its - * private fields, it has to apply same fixup on them. - * Otherwise, the custom-plan provider can skip this callback. + * The core implementation applies the routine to fixup varno + * on the target-list and scan qualifier. If custom-scan has + * additional expression nodes on its private fields, it has + * to apply same fixup on them. Otherwise, the custom-plan + * provider can skip this callback. */ if (cscan->methods->SetCustomScanRef) cscan->methods->SetCustomScanRef(root, cscan, rtoffset); @@ -1083,7 +1084,7 @@ copyVar(Var *var) * We assume it's okay to update opcode info in-place. So this could possibly * scribble on the planner's input data structures, but it's OK. */ -void +static void fix_expr_common(PlannerInfo *root, Node *node) { /* We assume callers won't call us on a NULL pointer */ diff --git a/src/backend/optimizer/util/pathnode.c b/src/backend/optimizer/util/pathnode.c index 6f1c6cfb2aa..121b9ff3e45 100644 --- a/src/backend/optimizer/util/pathnode.c +++ b/src/backend/optimizer/util/pathnode.c @@ -1929,10 +1929,10 @@ reparameterize_path(PlannerInfo *root, Path *path, } /***************************************************************************** - * creation of custom-plan paths + * creation of custom-plan paths *****************************************************************************/ -static List *custom_path_providers = NIL; +static List *custom_path_providers = NIL; /* * register_custom_path_provider @@ -1942,12 +1942,13 @@ static List *custom_path_providers = NIL; * methods of scanning a relation. */ void -register_custom_path_provider(CustomPathMethods *cpp_methods) +register_custom_path_provider(const CustomPathMethods *cpp_methods) { - MemoryContext oldcxt; + MemoryContext oldcxt; oldcxt = MemoryContextSwitchTo(TopMemoryContext); - custom_path_providers = lappend(custom_path_providers, cpp_methods); + custom_path_providers = lappend(custom_path_providers, + (void *) cpp_methods); MemoryContextSwitchTo(oldcxt); } @@ -1963,9 +1964,9 @@ create_customscan_paths(PlannerInfo *root, RelOptInfo *baserel, RangeTblEntry *rte) { - ListCell *cell; + ListCell *cell; - foreach (cell, custom_path_providers) + foreach(cell, custom_path_providers) { const CustomPathMethods *cpp_methods = lfirst(cell); diff --git a/src/include/executor/executor.h b/src/include/executor/executor.h index f1b65b4d050..ed3ae39b66d 100644 --- a/src/include/executor/executor.h +++ b/src/include/executor/executor.h @@ -16,7 +16,6 @@ #include "executor/execdesc.h" #include "nodes/parsenodes.h" -#include "nodes/relation.h" #include "utils/lockwaitpolicy.h" @@ -101,10 +100,12 @@ extern PGDLLIMPORT ExecutorCheckPerms_hook_type ExecutorCheckPerms_hook; /* * prototypes from functions in execAmi.c */ +struct Path; /* avoid including relation.h here */ + extern void ExecReScan(PlanState *node); extern void ExecMarkPos(PlanState *node); extern void ExecRestrPos(PlanState *node); -extern bool ExecSupportsMarkRestore(Path *pathnode); +extern bool ExecSupportsMarkRestore(struct Path *pathnode); extern bool ExecSupportsBackwardScan(Plan *node); extern bool ExecMaterializesOutput(NodeTag plantype); diff --git a/src/include/executor/nodeCustom.h b/src/include/executor/nodeCustom.h index 1736d48bfaf..e6f125544bc 100644 --- a/src/include/executor/nodeCustom.h +++ b/src/include/executor/nodeCustom.h @@ -11,14 +11,14 @@ */ #ifndef NODECUSTOM_H #define NODECUSTOM_H -#include "nodes/plannodes.h" + #include "nodes/execnodes.h" /* * General executor code */ extern CustomScanState *ExecInitCustomScan(CustomScan *custom_scan, - EState *estate, int eflags); + EState *estate, int eflags); extern TupleTableSlot *ExecCustomScan(CustomScanState *node); extern Node *MultiExecCustomScan(CustomScanState *node); extern void ExecEndCustomScan(CustomScanState *node); @@ -27,4 +27,4 @@ extern void ExecReScanCustomScan(CustomScanState *node); extern void ExecCustomMarkPos(CustomScanState *node); extern void ExecCustomRestrPos(CustomScanState *node); -#endif /* NODECUSTOM_H */ +#endif /* NODECUSTOM_H */ diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index 8c8c01f1cd2..40fb8243ab4 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -19,7 +19,6 @@ #include "executor/instrument.h" #include "nodes/params.h" #include "nodes/plannodes.h" -#include "nodes/relation.h" #include "utils/reltrigger.h" #include "utils/sortsupport.h" #include "utils/tuplestore.h" @@ -1512,39 +1511,39 @@ typedef struct ForeignScanState * CustomScan nodes are used to execute custom code within executor. * ---------------- */ -struct CustomExecMethods; -struct ExplainState; /* to avoid to include explain.h here */ +struct ExplainState; /* avoid including explain.h here */ +struct CustomScanState; + +typedef struct CustomExecMethods +{ + const char *CustomName; + + /* EXECUTOR methods */ + void (*BeginCustomScan) (struct CustomScanState *node, + EState *estate, + int eflags); + TupleTableSlot *(*ExecCustomScan) (struct CustomScanState *node); + void (*EndCustomScan) (struct CustomScanState *node); + void (*ReScanCustomScan) (struct CustomScanState *node); + void (*MarkPosCustomScan) (struct CustomScanState *node); + void (*RestrPosCustomScan) (struct CustomScanState *node); + + /* EXPLAIN support */ + void (*ExplainCustomScan) (struct CustomScanState *node, + List *ancestors, + struct ExplainState *es); + Node *(*GetSpecialCustomVar) (struct CustomScanState *node, + Var *varnode, + PlanState **child_ps); +} CustomExecMethods; typedef struct CustomScanState { ScanState ss; - uint32 flags; /* mask of CUSTOMPATH_* flags defined in relation.h*/ - const struct CustomExecMethods *methods; + uint32 flags; /* mask of CUSTOMPATH_* flags, see relation.h */ + const CustomExecMethods *methods; } CustomScanState; -typedef struct CustomExecMethods -{ - const char *CustomName; - - /* EXECUTOR methods */ - void (*BeginCustomScan)(CustomScanState *node, - EState *estate, - int eflags); - TupleTableSlot *(*ExecCustomScan)(CustomScanState *node); - void (*EndCustomScan)(CustomScanState *node); - void (*ReScanCustomScan)(CustomScanState *node); - void (*MarkPosCustomScan)(CustomScanState *node); - void (*RestrPosCustomScan)(CustomScanState *node); - - /* EXPLAIN support */ - void (*ExplainCustomScan)(CustomScanState *node, - List *ancestors, - struct ExplainState *es); - Node *(*GetSpecialCustomVar)(CustomScanState *node, - Var *varnode, - PlanState **child_ps); -} CustomExecMethods; - /* ---------------------------------------------------------------- * Join State Information * ---------------------------------------------------------------- diff --git a/src/include/nodes/plannodes.h b/src/include/nodes/plannodes.h index 9dbb91cb90d..dd300b1a191 100644 --- a/src/include/nodes/plannodes.h +++ b/src/include/nodes/plannodes.h @@ -18,7 +18,6 @@ #include "lib/stringinfo.h" #include "nodes/bitmapset.h" #include "nodes/primnodes.h" -#include "nodes/relation.h" #include "utils/lockwaitpolicy.h" @@ -486,33 +485,36 @@ typedef struct ForeignScan } ForeignScan; /* ---------------- - * CustomScan node + * CustomScan node * ---------------- */ -struct CustomScanMethods; - -typedef struct CustomScan -{ - Scan scan; - uint32 flags; /* mask of CUSTOMPATH_* flags defined in relation.h */ - struct CustomScanMethods *methods; -} CustomScan; +struct PlannerInfo; /* avoid including relation.h here */ +struct CustomScan; typedef struct CustomScanMethods { const char *CustomName; - void (*SetCustomScanRef)(struct PlannerInfo *root, - CustomScan *cscan, - int rtoffset); - void (*FinalizeCustomScan)(struct PlannerInfo *root, - CustomScan *cscan, - bool (*finalize_primnode)(), - void *finalize_context); - Node *(*CreateCustomScanState)(CustomScan *cscan); - void (*TextOutCustomScan)(StringInfo str, const CustomScan *node); - CustomScan *(*CopyCustomScan)(const CustomScan *from); + + void (*SetCustomScanRef) (struct PlannerInfo *root, + struct CustomScan *cscan, + int rtoffset); + void (*FinalizeCustomScan) (struct PlannerInfo *root, + struct CustomScan *cscan, + bool (*finalize_primnode) (), + void *finalize_context); + Node *(*CreateCustomScanState) (struct CustomScan *cscan); + void (*TextOutCustomScan) (StringInfo str, + const struct CustomScan *node); + struct CustomScan *(*CopyCustomScan) (const struct CustomScan *from); } CustomScanMethods; +typedef struct CustomScan +{ + Scan scan; + uint32 flags; /* mask of CUSTOMPATH_* flags, see relation.h */ + const CustomScanMethods *methods; +} CustomScan; + /* * ========== * Join nodes @@ -864,7 +866,7 @@ typedef struct PlanRowMark Index prti; /* range table index of parent relation */ Index rowmarkId; /* unique identifier for resjunk columns */ RowMarkType markType; /* see enum above */ - LockWaitPolicy waitPolicy; /* NOWAIT and SKIP LOCKED options */ + LockWaitPolicy waitPolicy; /* NOWAIT and SKIP LOCKED options */ bool isParent; /* true if this is a "dummy" parent entry */ } PlanRowMark; diff --git a/src/include/nodes/relation.h b/src/include/nodes/relation.h index 05cfbcd2aa1..7953bf7ed6c 100644 --- a/src/include/nodes/relation.h +++ b/src/include/nodes/relation.h @@ -897,34 +897,34 @@ typedef struct ForeignPath * the structure declared here; providers are expected to make it the first * element in a larger structure. */ - -struct CustomPathMethods; -struct Plan; /* not to include plannodes.h here */ +struct CustomPath; #define CUSTOMPATH_SUPPORT_BACKWARD_SCAN 0x0001 #define CUSTOMPATH_SUPPORT_MARK_RESTORE 0x0002 -typedef struct CustomPath -{ - Path path; - uint32 flags; - const struct CustomPathMethods *methods; -} CustomPath; - typedef struct CustomPathMethods { const char *CustomName; - void (*CreateCustomScanPath)(PlannerInfo *root, - RelOptInfo *baserel, - RangeTblEntry *rte); - struct Plan *(*PlanCustomPath)(PlannerInfo *root, - RelOptInfo *rel, - CustomPath *best_path, - List *tlist, - List *clauses); - void (*TextOutCustomPath)(StringInfo str, const CustomPath *node); + + void (*CreateCustomScanPath) (PlannerInfo *root, + RelOptInfo *baserel, + RangeTblEntry *rte); + struct Plan *(*PlanCustomPath) (PlannerInfo *root, + RelOptInfo *rel, + struct CustomPath *best_path, + List *tlist, + List *clauses); + void (*TextOutCustomPath) (StringInfo str, + const struct CustomPath *node); } CustomPathMethods; +typedef struct CustomPath +{ + Path path; + uint32 flags; /* mask of CUSTOMPATH_* flags, see above */ + const CustomPathMethods *methods; +} CustomPath; + /* * AppendPath represents an Append plan, ie, successive execution of * several member plans. diff --git a/src/include/optimizer/pathnode.h b/src/include/optimizer/pathnode.h index 2b67ae6187b..0f2882986c0 100644 --- a/src/include/optimizer/pathnode.h +++ b/src/include/optimizer/pathnode.h @@ -131,11 +131,11 @@ extern Path *reparameterize_path(PlannerInfo *root, Path *path, /* * Interface definition of custom-scan providers */ -extern void register_custom_path_provider(CustomPathMethods *cpp_methods); +extern void register_custom_path_provider(const CustomPathMethods *cpp_methods); extern void create_customscan_paths(PlannerInfo *root, - RelOptInfo *baserel, - RangeTblEntry *rte); + RelOptInfo *baserel, + RangeTblEntry *rte); /* * prototypes for relnode.c diff --git a/src/include/optimizer/planmain.h b/src/include/optimizer/planmain.h index c97c5777a07..d6dae8e738e 100644 --- a/src/include/optimizer/planmain.h +++ b/src/include/optimizer/planmain.h @@ -130,9 +130,8 @@ extern bool query_is_distinct_for(Query *query, List *colnos, List *opids); * prototypes for plan/setrefs.c */ extern Plan *set_plan_references(PlannerInfo *root, Plan *plan); -extern void fix_opfuncids(Node *node); extern Node *fix_scan_expr(PlannerInfo *root, Node *node, int rtoffset); -extern void fix_expr_common(PlannerInfo *root, Node *node); +extern void fix_opfuncids(Node *node); extern void set_opfuncid(OpExpr *opexpr); extern void set_sa_opfuncid(ScalarArrayOpExpr *opexpr); extern void record_plan_function_dependency(PlannerInfo *root, Oid funcid);