On Tue, May 10, 2022 at 05:55:12PM +0900, Michael Paquier wrote:
> I agree that removing support for the unloading part would be nice to
> clean up now on HEAD. Note that 0002 is missing the removal of one
> reference to _PG_fini in xfunc.sgml (<primary> markup).
Oops, sorry about that.
--
Nathan Bossart
Amazon Web Services: https://aws.amazon.com
>From e19bc075c5e98b655afa6ecc183c7de7adf217a8 Mon Sep 17 00:00:00 2001
From: Nathan Bossart <nathandboss...@gmail.com>
Date: Mon, 18 Apr 2022 15:25:37 -0700
Subject: [PATCH v7 1/2] Add a new shmem_request_hook hook.
Currently, preloaded libraries are expected to request additional
shared memory and LWLocks in _PG_init(). However, it is not unusal
for such requests to depend on MaxBackends, which won't be
initialized at that time. Such requests could also depend on GUCs
that other modules might change. This introduces a new hook where
modules can safely use MaxBackends and GUCs to request additional
shared memory and LWLocks.
Furthermore, this change restricts requests for shared memory and
LWLocks to this hook. Previously, libraries could make requests
until the size of the main shared memory segment was calculated.
Unlike before, we no longer silently ignore requests received at
invalid times. Instead, we FATAL if someone tries to request
additional shared memory or LWLocks outside of the hook.
Authors: Julien Rouhaud, Nathan Bossart
Discussion: https://postgr.es/m/20220412210112.GA2065815%40nathanxps13
---
contrib/pg_prewarm/autoprewarm.c | 17 +++++++++++-
.../pg_stat_statements/pg_stat_statements.c | 27 +++++++++++++------
src/backend/postmaster/postmaster.c | 5 ++++
src/backend/storage/ipc/ipci.c | 20 +++++---------
src/backend/storage/lmgr/lwlock.c | 18 ++++---------
src/backend/utils/init/miscinit.c | 15 +++++++++++
src/include/miscadmin.h | 5 ++++
src/tools/pgindent/typedefs.list | 1 +
8 files changed, 72 insertions(+), 36 deletions(-)
diff --git a/contrib/pg_prewarm/autoprewarm.c b/contrib/pg_prewarm/autoprewarm.c
index 45e012a63a..c0c4f5d9ca 100644
--- a/contrib/pg_prewarm/autoprewarm.c
+++ b/contrib/pg_prewarm/autoprewarm.c
@@ -96,6 +96,8 @@ static void apw_start_database_worker(void);
static bool apw_init_shmem(void);
static void apw_detach_shmem(int code, Datum arg);
static int apw_compare_blockinfo(const void *p, const void *q);
+static void autoprewarm_shmem_request(void);
+static shmem_request_hook_type prev_shmem_request_hook = NULL;
/* Pointer to shared-memory state. */
static AutoPrewarmSharedState *apw_state = NULL;
@@ -139,13 +141,26 @@ _PG_init(void)
MarkGUCPrefixReserved("pg_prewarm");
- RequestAddinShmemSpace(MAXALIGN(sizeof(AutoPrewarmSharedState)));
+ prev_shmem_request_hook = shmem_request_hook;
+ shmem_request_hook = autoprewarm_shmem_request;
/* Register autoprewarm worker, if enabled. */
if (autoprewarm)
apw_start_leader_worker();
}
+/*
+ * Requests any additional shared memory required for autoprewarm.
+ */
+static void
+autoprewarm_shmem_request(void)
+{
+ if (prev_shmem_request_hook)
+ prev_shmem_request_hook();
+
+ RequestAddinShmemSpace(MAXALIGN(sizeof(AutoPrewarmSharedState)));
+}
+
/*
* Main entry point for the leader autoprewarm process. Per-database workers
* have a separate entry point.
diff --git a/contrib/pg_stat_statements/pg_stat_statements.c b/contrib/pg_stat_statements/pg_stat_statements.c
index df2ce63790..87b75d779e 100644
--- a/contrib/pg_stat_statements/pg_stat_statements.c
+++ b/contrib/pg_stat_statements/pg_stat_statements.c
@@ -252,6 +252,7 @@ static int exec_nested_level = 0;
static int plan_nested_level = 0;
/* Saved hook values in case of unload */
+static shmem_request_hook_type prev_shmem_request_hook = NULL;
static shmem_startup_hook_type prev_shmem_startup_hook = NULL;
static post_parse_analyze_hook_type prev_post_parse_analyze_hook = NULL;
static planner_hook_type prev_planner_hook = NULL;
@@ -317,6 +318,7 @@ PG_FUNCTION_INFO_V1(pg_stat_statements_1_10);
PG_FUNCTION_INFO_V1(pg_stat_statements);
PG_FUNCTION_INFO_V1(pg_stat_statements_info);
+static void pgss_shmem_request(void);
static void pgss_shmem_startup(void);
static void pgss_shmem_shutdown(int code, Datum arg);
static void pgss_post_parse_analyze(ParseState *pstate, Query *query,
@@ -452,17 +454,11 @@ _PG_init(void)
MarkGUCPrefixReserved("pg_stat_statements");
- /*
- * Request additional shared resources. (These are no-ops if we're not in
- * the postmaster process.) We'll allocate or attach to the shared
- * resources in pgss_shmem_startup().
- */
- RequestAddinShmemSpace(pgss_memsize());
- RequestNamedLWLockTranche("pg_stat_statements", 1);
-
/*
* Install hooks.
*/
+ prev_shmem_request_hook = shmem_request_hook;
+ shmem_request_hook = pgss_shmem_request;
prev_shmem_startup_hook = shmem_startup_hook;
shmem_startup_hook = pgss_shmem_startup;
prev_post_parse_analyze_hook = post_parse_analyze_hook;
@@ -488,6 +484,7 @@ void
_PG_fini(void)
{
/* Uninstall hooks. */
+ shmem_request_hook = prev_shmem_request_hook;
shmem_startup_hook = prev_shmem_startup_hook;
post_parse_analyze_hook = prev_post_parse_analyze_hook;
planner_hook = prev_planner_hook;
@@ -498,6 +495,20 @@ _PG_fini(void)
ProcessUtility_hook = prev_ProcessUtility;
}
+/*
+ * shmem_request hook: request additional shared resources. We'll allocate or
+ * attach to the shared resources in pgss_shmem_startup().
+ */
+static void
+pgss_shmem_request(void)
+{
+ if (prev_shmem_request_hook)
+ prev_shmem_request_hook();
+
+ RequestAddinShmemSpace(pgss_memsize());
+ RequestNamedLWLockTranche("pg_stat_statements", 1);
+}
+
/*
* shmem_startup hook: allocate or attach to shared memory,
* then load any pre-existing statistics from file.
diff --git a/src/backend/postmaster/postmaster.c b/src/backend/postmaster/postmaster.c
index ce4007bb2c..99d5b2fc1f 100644
--- a/src/backend/postmaster/postmaster.c
+++ b/src/backend/postmaster/postmaster.c
@@ -1032,6 +1032,11 @@ PostmasterMain(int argc, char *argv[])
*/
InitializeMaxBackends();
+ /*
+ * Give preloaded libraries a chance to request additional shared memory.
+ */
+ process_shmem_requests();
+
/*
* Now that loadable modules have had their chance to request additional
* shared memory, determine the value of any runtime-computed GUCs that
diff --git a/src/backend/storage/ipc/ipci.c b/src/backend/storage/ipc/ipci.c
index 75e456360b..26372d95b3 100644
--- a/src/backend/storage/ipc/ipci.c
+++ b/src/backend/storage/ipc/ipci.c
@@ -55,25 +55,21 @@ int shared_memory_type = DEFAULT_SHARED_MEMORY_TYPE;
shmem_startup_hook_type shmem_startup_hook = NULL;
static Size total_addin_request = 0;
-static bool addin_request_allowed = true;
-
/*
* RequestAddinShmemSpace
* Request that extra shmem space be allocated for use by
* a loadable module.
*
- * This is only useful if called from the _PG_init hook of a library that
- * is loaded into the postmaster via shared_preload_libraries. Once
- * shared memory has been allocated, calls will be ignored. (We could
- * raise an error, but it seems better to make it a no-op, so that
- * libraries containing such calls can be reloaded if needed.)
+ * This may only be called via the shmem_request_hook of a library that is
+ * loaded into the postmaster via shared_preload_libraries. Calls from
+ * elsewhere will fail.
*/
void
RequestAddinShmemSpace(Size size)
{
- if (IsUnderPostmaster || !addin_request_allowed)
- return; /* too late */
+ if (!process_shmem_requests_in_progress)
+ elog(FATAL, "cannot request additional shared memory outside shmem_request_hook");
total_addin_request = add_size(total_addin_request, size);
}
@@ -83,9 +79,6 @@ RequestAddinShmemSpace(Size size)
*
* If num_semaphores is not NULL, it will be set to the number of semaphores
* required.
- *
- * Note that this function freezes the additional shared memory request size
- * from loadable modules.
*/
Size
CalculateShmemSize(int *num_semaphores)
@@ -152,8 +145,7 @@ CalculateShmemSize(int *num_semaphores)
size = add_size(size, ShmemBackendArraySize());
#endif
- /* freeze the addin request size and include it */
- addin_request_allowed = false;
+ /* include additional requested shmem from preload libraries */
size = add_size(size, total_addin_request);
/* might as well round it off to a multiple of a typical page size */
diff --git a/src/backend/storage/lmgr/lwlock.c b/src/backend/storage/lmgr/lwlock.c
index fef462b110..8aef909037 100644
--- a/src/backend/storage/lmgr/lwlock.c
+++ b/src/backend/storage/lmgr/lwlock.c
@@ -243,8 +243,6 @@ int NamedLWLockTrancheRequests = 0;
/* points to data in shared memory: */
NamedLWLockTranche *NamedLWLockTrancheArray = NULL;
-static bool lock_named_request_allowed = true;
-
static void InitializeLWLocks(void);
static inline void LWLockReportWaitStart(LWLock *lock);
static inline void LWLockReportWaitEnd(void);
@@ -458,9 +456,6 @@ LWLockShmemSize(void)
for (i = 0; i < NamedLWLockTrancheRequests; i++)
size = add_size(size, strlen(NamedLWLockTrancheRequestArray[i].tranche_name) + 1);
- /* Disallow adding any more named tranches. */
- lock_named_request_allowed = false;
-
return size;
}
@@ -691,12 +686,9 @@ LWLockRegisterTranche(int tranche_id, const char *tranche_name)
* Request that extra LWLocks be allocated during postmaster
* startup.
*
- * This is only useful for extensions if called from the _PG_init hook
- * of a library that is loaded into the postmaster via
- * shared_preload_libraries. Once shared memory has been allocated, calls
- * will be ignored. (We could raise an error, but it seems better to make
- * it a no-op, so that libraries containing such calls can be reloaded if
- * needed.)
+ * This may only be called via the shmem_request_hook of a library that is
+ * loaded into the postmaster via shared_preload_libraries. Calls from
+ * elsewhere will fail.
*
* The tranche name will be user-visible as a wait event name, so try to
* use a name that fits the style for those.
@@ -706,8 +698,8 @@ RequestNamedLWLockTranche(const char *tranche_name, int num_lwlocks)
{
NamedLWLockTrancheRequest *request;
- if (IsUnderPostmaster || !lock_named_request_allowed)
- return; /* too late */
+ if (!process_shmem_requests_in_progress)
+ elog(FATAL, "cannot request additional LWLocks outside shmem_request_hook");
if (NamedLWLockTrancheRequestArray == NULL)
{
diff --git a/src/backend/utils/init/miscinit.c b/src/backend/utils/init/miscinit.c
index 6ed584e114..ec6a61594a 100644
--- a/src/backend/utils/init/miscinit.c
+++ b/src/backend/utils/init/miscinit.c
@@ -1618,6 +1618,9 @@ char *local_preload_libraries_string = NULL;
bool process_shared_preload_libraries_in_progress = false;
bool process_shared_preload_libraries_done = false;
+shmem_request_hook_type shmem_request_hook = NULL;
+bool process_shmem_requests_in_progress = false;
+
/*
* load the shared libraries listed in 'libraries'
*
@@ -1701,6 +1704,18 @@ process_session_preload_libraries(void)
true);
}
+/*
+ * process any shared memory requests from preloaded libraries
+ */
+void
+process_shmem_requests(void)
+{
+ process_shmem_requests_in_progress = true;
+ if (shmem_request_hook)
+ shmem_request_hook();
+ process_shmem_requests_in_progress = false;
+}
+
void
pg_bindtextdomain(const char *domain)
{
diff --git a/src/include/miscadmin.h b/src/include/miscadmin.h
index 53fd168d93..0af130fbc5 100644
--- a/src/include/miscadmin.h
+++ b/src/include/miscadmin.h
@@ -465,6 +465,7 @@ extern void BaseInit(void);
extern PGDLLIMPORT bool IgnoreSystemIndexes;
extern PGDLLIMPORT bool process_shared_preload_libraries_in_progress;
extern PGDLLIMPORT bool process_shared_preload_libraries_done;
+extern PGDLLIMPORT bool process_shmem_requests_in_progress;
extern PGDLLIMPORT char *session_preload_libraries_string;
extern PGDLLIMPORT char *shared_preload_libraries_string;
extern PGDLLIMPORT char *local_preload_libraries_string;
@@ -478,9 +479,13 @@ extern bool RecheckDataDirLockFile(void);
extern void ValidatePgVersion(const char *path);
extern void process_shared_preload_libraries(void);
extern void process_session_preload_libraries(void);
+extern void process_shmem_requests(void);
extern void pg_bindtextdomain(const char *domain);
extern bool has_rolreplication(Oid roleid);
+typedef void (*shmem_request_hook_type) (void);
+extern PGDLLIMPORT shmem_request_hook_type shmem_request_hook;
+
/* in executor/nodeHash.c */
extern size_t get_hash_memory_limit(void);
diff --git a/src/tools/pgindent/typedefs.list b/src/tools/pgindent/typedefs.list
index 87ee7bf866..71a97654e0 100644
--- a/src/tools/pgindent/typedefs.list
+++ b/src/tools/pgindent/typedefs.list
@@ -3549,6 +3549,7 @@ shm_mq_result
shm_toc
shm_toc_entry
shm_toc_estimator
+shmem_request_hook_type
shmem_startup_hook_type
sig_atomic_t
sigjmp_buf
--
2.25.1
>From a2471fd16262ffa30f3278360d7d9a8c41b67d3d Mon Sep 17 00:00:00 2001
From: Nathan Bossart <nathandboss...@gmail.com>
Date: Fri, 6 May 2022 13:53:54 -0700
Subject: [PATCH v7 2/2] Remove logic for unloading dynamically loaded files.
The code for unloading a library has been commented-out for over 12
years (602a9ef), and we're no closer to supporting it now than we
were back then.
---
contrib/auto_explain/auto_explain.c | 14 ----
contrib/passwordcheck/passwordcheck.c | 11 ---
.../pg_stat_statements/pg_stat_statements.c | 19 -----
doc/src/sgml/xfunc.sgml | 18 +----
src/backend/postmaster/pgarch.c | 2 +-
src/backend/utils/fmgr/dfmgr.c | 77 ++-----------------
src/backend/utils/fmgr/fmgr.c | 14 ----
src/include/fmgr.h | 1 -
src/pl/plpgsql/src/plpgsql.h | 2 -
.../modules/delay_execution/delay_execution.c | 10 +--
.../ssl_passphrase_func.c | 7 --
.../modules/test_oat_hooks/test_oat_hooks.c | 22 +-----
.../modules/test_rls_hooks/test_rls_hooks.c | 17 ----
13 files changed, 13 insertions(+), 201 deletions(-)
diff --git a/contrib/auto_explain/auto_explain.c b/contrib/auto_explain/auto_explain.c
index d3029f85ef..c9a0d947c8 100644
--- a/contrib/auto_explain/auto_explain.c
+++ b/contrib/auto_explain/auto_explain.c
@@ -77,7 +77,6 @@ static ExecutorFinish_hook_type prev_ExecutorFinish = NULL;
static ExecutorEnd_hook_type prev_ExecutorEnd = NULL;
void _PG_init(void);
-void _PG_fini(void);
static void explain_ExecutorStart(QueryDesc *queryDesc, int eflags);
static void explain_ExecutorRun(QueryDesc *queryDesc,
@@ -244,19 +243,6 @@ _PG_init(void)
ExecutorEnd_hook = explain_ExecutorEnd;
}
-/*
- * Module unload callback
- */
-void
-_PG_fini(void)
-{
- /* Uninstall hooks. */
- ExecutorStart_hook = prev_ExecutorStart;
- ExecutorRun_hook = prev_ExecutorRun;
- ExecutorFinish_hook = prev_ExecutorFinish;
- ExecutorEnd_hook = prev_ExecutorEnd;
-}
-
/*
* ExecutorStart hook: start up logging if needed
*/
diff --git a/contrib/passwordcheck/passwordcheck.c b/contrib/passwordcheck/passwordcheck.c
index 074836336d..9d8c58ded0 100644
--- a/contrib/passwordcheck/passwordcheck.c
+++ b/contrib/passwordcheck/passwordcheck.c
@@ -33,7 +33,6 @@ static check_password_hook_type prev_check_password_hook = NULL;
#define MIN_PWD_LENGTH 8
extern void _PG_init(void);
-extern void _PG_fini(void);
/*
* check_password
@@ -149,13 +148,3 @@ _PG_init(void)
prev_check_password_hook = check_password_hook;
check_password_hook = check_password;
}
-
-/*
- * Module unload function
- */
-void
-_PG_fini(void)
-{
- /* uninstall hook */
- check_password_hook = prev_check_password_hook;
-}
diff --git a/contrib/pg_stat_statements/pg_stat_statements.c b/contrib/pg_stat_statements/pg_stat_statements.c
index 87b75d779e..9ea887d887 100644
--- a/contrib/pg_stat_statements/pg_stat_statements.c
+++ b/contrib/pg_stat_statements/pg_stat_statements.c
@@ -306,7 +306,6 @@ static bool pgss_save; /* whether to save stats across shutdown */
/*---- Function declarations ----*/
void _PG_init(void);
-void _PG_fini(void);
PG_FUNCTION_INFO_V1(pg_stat_statements_reset);
PG_FUNCTION_INFO_V1(pg_stat_statements_reset_1_7);
@@ -477,24 +476,6 @@ _PG_init(void)
ProcessUtility_hook = pgss_ProcessUtility;
}
-/*
- * Module unload callback
- */
-void
-_PG_fini(void)
-{
- /* Uninstall hooks. */
- shmem_request_hook = prev_shmem_request_hook;
- shmem_startup_hook = prev_shmem_startup_hook;
- post_parse_analyze_hook = prev_post_parse_analyze_hook;
- planner_hook = prev_planner_hook;
- ExecutorStart_hook = prev_ExecutorStart;
- ExecutorRun_hook = prev_ExecutorRun;
- ExecutorFinish_hook = prev_ExecutorFinish;
- ExecutorEnd_hook = prev_ExecutorEnd;
- ProcessUtility_hook = prev_ProcessUtility;
-}
-
/*
* shmem_request hook: request additional shared resources. We'll allocate or
* attach to the shared resources in pgss_shmem_startup().
diff --git a/doc/src/sgml/xfunc.sgml b/doc/src/sgml/xfunc.sgml
index 07c5fd198b..fbe718e3c2 100644
--- a/doc/src/sgml/xfunc.sgml
+++ b/doc/src/sgml/xfunc.sgml
@@ -1978,28 +1978,16 @@ PG_MODULE_MAGIC;
<indexterm zone="xfunc-c-dynload">
<primary>_PG_init</primary>
</indexterm>
- <indexterm zone="xfunc-c-dynload">
- <primary>_PG_fini</primary>
- </indexterm>
<indexterm zone="xfunc-c-dynload">
<primary>library initialization function</primary>
</indexterm>
- <indexterm zone="xfunc-c-dynload">
- <primary>library finalization function</primary>
- </indexterm>
<para>
- Optionally, a dynamically loaded file can contain initialization and
- finalization functions. If the file includes a function named
+ Optionally, a dynamically loaded file can contain an initialization
+ function. If the file includes a function named
<function>_PG_init</function>, that function will be called immediately after
loading the file. The function receives no parameters and should
- return void. If the file includes a function named
- <function>_PG_fini</function>, that function will be called immediately before
- unloading the file. Likewise, the function receives no parameters and
- should return void. Note that <function>_PG_fini</function> will only be called
- during an unload of the file, not during process termination.
- (Presently, unloads are disabled and will never occur, but this may
- change in the future.)
+ return void. There is presently no way to unload a dynamically loaded file.
</para>
</sect2>
diff --git a/src/backend/postmaster/pgarch.c b/src/backend/postmaster/pgarch.c
index 0c8ca29f73..8beff4a53c 100644
--- a/src/backend/postmaster/pgarch.c
+++ b/src/backend/postmaster/pgarch.c
@@ -802,7 +802,7 @@ HandlePgArchInterrupts(void)
* Ideally, we would simply unload the previous archive module and
* load the new one, but there is presently no mechanism for
* unloading a library (see the comment above
- * internal_unload_library()). To deal with this, we simply restart
+ * internal_load_library()). To deal with this, we simply restart
* the archiver. The new archive module will be loaded when the new
* archiver process starts up.
*/
diff --git a/src/backend/utils/fmgr/dfmgr.c b/src/backend/utils/fmgr/dfmgr.c
index 3774f33e0e..7f9ea97280 100644
--- a/src/backend/utils/fmgr/dfmgr.c
+++ b/src/backend/utils/fmgr/dfmgr.c
@@ -37,9 +37,8 @@
#include "utils/hsearch.h"
-/* signatures for PostgreSQL-specific library init/fini functions */
+/* signature for PostgreSQL-specific library init function */
typedef void (*PG_init_t) (void);
-typedef void (*PG_fini_t) (void);
/* hashtable entry for rendezvous variables */
typedef struct
@@ -79,7 +78,6 @@ char *Dynamic_library_path;
static void *internal_load_library(const char *libname);
static void incompatible_module_error(const char *libname,
const Pg_magic_struct *module_magic_data) pg_attribute_noreturn();
-static void internal_unload_library(const char *libname);
static bool file_exists(const char *name);
static char *expand_dynamic_library_name(const char *name);
static void check_restricted_library_name(const char *name);
@@ -154,9 +152,6 @@ load_file(const char *filename, bool restricted)
/* Expand the possibly-abbreviated filename to an exact path name */
fullname = expand_dynamic_library_name(filename);
- /* Unload the library if currently loaded */
- internal_unload_library(fullname);
-
/* Load the shared library */
(void) internal_load_library(fullname);
@@ -179,6 +174,11 @@ lookup_external_function(void *filehandle, const char *funcname)
* loaded. Return the pg_dl* handle for the file.
*
* Note: libname is expected to be an exact name for the library file.
+ *
+ * NB: There is presently no way to unload a dynamically loaded file. We might
+ * add one someday if we can convince ourselves we have safe protocols for un-
+ * hooking from hook function pointers, releasing custom GUC variables, and
+ * perhaps other things that are definitely unsafe currently.
*/
static void *
internal_load_library(const char *libname)
@@ -400,71 +400,6 @@ incompatible_module_error(const char *libname,
errdetail_internal("%s", details.data)));
}
-/*
- * Unload the specified dynamic-link library file, if it is loaded.
- *
- * Note: libname is expected to be an exact name for the library file.
- *
- * XXX for the moment, this is disabled, resulting in LOAD of an already-loaded
- * library always being a no-op. We might re-enable it someday if we can
- * convince ourselves we have safe protocols for un-hooking from hook function
- * pointers, releasing custom GUC variables, and perhaps other things that
- * are definitely unsafe currently.
- */
-static void
-internal_unload_library(const char *libname)
-{
-#ifdef NOT_USED
- DynamicFileList *file_scanner,
- *prv,
- *nxt;
- struct stat stat_buf;
- PG_fini_t PG_fini;
-
- /*
- * We need to do stat() in order to determine whether this is the same
- * file as a previously loaded file; it's also handy so as to give a good
- * error message if bogus file name given.
- */
- if (stat(libname, &stat_buf) == -1)
- ereport(ERROR,
- (errcode_for_file_access(),
- errmsg("could not access file \"%s\": %m", libname)));
-
- /*
- * We have to zap all entries in the list that match on either filename or
- * inode, else internal_load_library() will still think it's present.
- */
- prv = NULL;
- for (file_scanner = file_list; file_scanner != NULL; file_scanner = nxt)
- {
- nxt = file_scanner->next;
- if (strcmp(libname, file_scanner->filename) == 0 ||
- SAME_INODE(stat_buf, *file_scanner))
- {
- if (prv)
- prv->next = nxt;
- else
- file_list = nxt;
-
- /*
- * If the library has a _PG_fini() function, call it.
- */
- PG_fini = (PG_fini_t) dlsym(file_scanner->handle, "_PG_fini");
- if (PG_fini)
- (*PG_fini) ();
-
- clear_external_function_hash(file_scanner->handle);
- dlclose(file_scanner->handle);
- free((char *) file_scanner);
- /* prv does not change */
- }
- else
- prv = file_scanner;
- }
-#endif /* NOT_USED */
-}
-
static bool
file_exists(const char *name)
{
diff --git a/src/backend/utils/fmgr/fmgr.c b/src/backend/utils/fmgr/fmgr.c
index b2e72b3243..a9dd068095 100644
--- a/src/backend/utils/fmgr/fmgr.c
+++ b/src/backend/utils/fmgr/fmgr.c
@@ -582,20 +582,6 @@ record_C_func(HeapTuple procedureTuple,
entry->inforec = inforec;
}
-/*
- * clear_external_function_hash: remove entries for a library being closed
- *
- * Presently we just zap the entire hash table, but later it might be worth
- * the effort to remove only the entries associated with the given handle.
- */
-void
-clear_external_function_hash(void *filehandle)
-{
- if (CFuncHash)
- hash_destroy(CFuncHash);
- CFuncHash = NULL;
-}
-
/*
* Copy an FmgrInfo struct
diff --git a/src/include/fmgr.h b/src/include/fmgr.h
index a1cf4bd646..d55abc5414 100644
--- a/src/include/fmgr.h
+++ b/src/include/fmgr.h
@@ -705,7 +705,6 @@ extern bytea *OidSendFunctionCall(Oid functionId, Datum val);
* Routines in fmgr.c
*/
extern const Pg_finfo_record *fetch_finfo_record(void *filehandle, const char *funcname);
-extern void clear_external_function_hash(void *filehandle);
extern Oid fmgr_internal_function(const char *proname);
extern Oid get_fn_expr_rettype(FmgrInfo *flinfo);
extern Oid get_fn_expr_argtype(FmgrInfo *flinfo, int argnum);
diff --git a/src/pl/plpgsql/src/plpgsql.h b/src/pl/plpgsql/src/plpgsql.h
index 6444347ce9..4e6ee1c619 100644
--- a/src/pl/plpgsql/src/plpgsql.h
+++ b/src/pl/plpgsql/src/plpgsql.h
@@ -1100,8 +1100,6 @@ typedef struct PLpgSQL_execstate
* variable "PLpgSQL_plugin" and set it to point to a PLpgSQL_plugin struct.
* Typically the struct could just be static data in the plugin library.
* We expect that a plugin would do this at library load time (_PG_init()).
- * It must also be careful to set the rendezvous variable back to NULL
- * if it is unloaded (_PG_fini()).
*
* This structure is basically a collection of function pointers --- at
* various interesting points in pl_exec.c, we call these functions
diff --git a/src/test/modules/delay_execution/delay_execution.c b/src/test/modules/delay_execution/delay_execution.c
index cf34e8c2d7..407ebc0eda 100644
--- a/src/test/modules/delay_execution/delay_execution.c
+++ b/src/test/modules/delay_execution/delay_execution.c
@@ -36,9 +36,8 @@ static int post_planning_lock_id = 0;
/* Save previous planner hook user to be a good citizen */
static planner_hook_type prev_planner_hook = NULL;
-/* Module load/unload functions */
+/* Module load function */
void _PG_init(void);
-void _PG_fini(void);
/* planner_hook function to provide the desired delay */
@@ -97,10 +96,3 @@ _PG_init(void)
prev_planner_hook = planner_hook;
planner_hook = delay_execution_planner;
}
-
-/* Module unload function (pro forma, not used currently) */
-void
-_PG_fini(void)
-{
- planner_hook = prev_planner_hook;
-}
diff --git a/src/test/modules/ssl_passphrase_callback/ssl_passphrase_func.c b/src/test/modules/ssl_passphrase_callback/ssl_passphrase_func.c
index b5bb5580a0..e9f2329a5a 100644
--- a/src/test/modules/ssl_passphrase_callback/ssl_passphrase_func.c
+++ b/src/test/modules/ssl_passphrase_callback/ssl_passphrase_func.c
@@ -21,7 +21,6 @@
PG_MODULE_MAGIC;
void _PG_init(void);
-void _PG_fini(void);
static char *ssl_passphrase = NULL;
@@ -55,12 +54,6 @@ _PG_init(void)
openssl_tls_init_hook = set_rot13;
}
-void
-_PG_fini(void)
-{
- /* do nothing yet */
-}
-
static void
set_rot13(SSL_CTX *context, bool isServerStart)
{
diff --git a/src/test/modules/test_oat_hooks/test_oat_hooks.c b/src/test/modules/test_oat_hooks/test_oat_hooks.c
index 551da5d498..6f9838f93b 100644
--- a/src/test/modules/test_oat_hooks/test_oat_hooks.c
+++ b/src/test/modules/test_oat_hooks/test_oat_hooks.c
@@ -43,7 +43,7 @@ static bool REGRESS_userset_variable2 = false;
static bool REGRESS_suset_variable1 = false;
static bool REGRESS_suset_variable2 = false;
-/* Saved hook values in case of unload */
+/* Saved hook values */
static object_access_hook_type next_object_access_hook = NULL;
static object_access_hook_type_str next_object_access_hook_str = NULL;
static ExecutorCheckPerms_hook_type next_exec_check_perms_hook = NULL;
@@ -70,10 +70,9 @@ static char *accesstype_arg_to_string(ObjectAccessType access, void *arg);
void _PG_init(void);
-void _PG_fini(void);
/*
- * Module load/unload callback
+ * Module load callback
*/
void
_PG_init(void)
@@ -231,23 +230,6 @@ _PG_init(void)
ProcessUtility_hook = REGRESS_utility_command;
}
-void
-_PG_fini(void)
-{
- /* Unload hooks */
- if (object_access_hook == REGRESS_object_access_hook)
- object_access_hook = next_object_access_hook;
-
- if (object_access_hook_str == REGRESS_object_access_hook_str)
- object_access_hook_str = next_object_access_hook_str;
-
- if (ExecutorCheckPerms_hook == REGRESS_exec_check_perms)
- ExecutorCheckPerms_hook = next_exec_check_perms_hook;
-
- if (ProcessUtility_hook == REGRESS_utility_command)
- ProcessUtility_hook = next_ProcessUtility_hook;
-}
-
static void
emit_audit_message(const char *type, const char *hook, char *action, char *objName)
{
diff --git a/src/test/modules/test_rls_hooks/test_rls_hooks.c b/src/test/modules/test_rls_hooks/test_rls_hooks.c
index 4f862d081b..b8e0aa2d0b 100644
--- a/src/test/modules/test_rls_hooks/test_rls_hooks.c
+++ b/src/test/modules/test_rls_hooks/test_rls_hooks.c
@@ -29,34 +29,17 @@
PG_MODULE_MAGIC;
-/* Saved hook values in case of unload */
-static row_security_policy_hook_type prev_row_security_policy_hook_permissive = NULL;
-static row_security_policy_hook_type prev_row_security_policy_hook_restrictive = NULL;
-
void _PG_init(void);
-void _PG_fini(void);
/* Install hooks */
void
_PG_init(void)
{
- /* Save values for unload */
- prev_row_security_policy_hook_permissive = row_security_policy_hook_permissive;
- prev_row_security_policy_hook_restrictive = row_security_policy_hook_restrictive;
-
/* Set our hooks */
row_security_policy_hook_permissive = test_rls_hooks_permissive;
row_security_policy_hook_restrictive = test_rls_hooks_restrictive;
}
-/* Uninstall hooks */
-void
-_PG_fini(void)
-{
- row_security_policy_hook_permissive = prev_row_security_policy_hook_permissive;
- row_security_policy_hook_restrictive = prev_row_security_policy_hook_restrictive;
-}
-
/*
* Return permissive policies to be added
*/
--
2.25.1
