From 52cc1f8ede787e654bbe5e8092b6a58db5c504ee Mon Sep 17 00:00:00 2001
From: Konstantin Knizhnik <knizhnik@neon.tech>
Date: Thu, 9 Nov 2023 19:33:41 +0200
Subject: [PATCH] Merge with main

---
 pgxn/neon/libpagestore.c     | 88 ++----------------------------------
 pgxn/neon/pagestore_client.h |  4 ++
 2 files changed, 8 insertions(+), 84 deletions(-)

diff --git a/pgxn/neon/libpagestore.c b/pgxn/neon/libpagestore.c
index 633083809c..fcf69f7c7c 100644
--- a/pgxn/neon/libpagestore.c
+++ b/pgxn/neon/libpagestore.c
@@ -66,10 +66,6 @@ static shmem_startup_hook_type prev_shmem_startup_hook;
 static shmem_request_hook_type prev_shmem_request_hook;
 #endif
 
-#define MAX_SHARDS 128
-#define STRIPE_SIZE (256 * 1024 / 8) /* TODO: should in betaken from control plane? */
-#define MAX_PS_CONNSTR_LEN 128
-
 typedef struct
 {
 	size_t n_shards;
@@ -150,7 +146,7 @@ psm_init(void)
  * Reload page map if needed and return number of shards and connection string for the specified shard
  */
 static shardno_t
-load_page_map(shardno_t shard_no, char* connstr)
+load_shard_map(shardno_t shard_no, char* connstr)
 {
 	shardno_t n_shards;
 
@@ -204,7 +200,7 @@ load_page_map(shardno_t shard_no, char* connstr)
 shardno_t
 get_shard_number(BufferTag* tag)
 {
-	shardno_t n_shards = load_page_map(0, NULL);
+	shardno_t n_shards = load_shard_map(0, NULL);
 	uint32	  hash;
 
 #if PG_MAJORVERSION_NUM < 16
@@ -222,21 +218,6 @@ get_shard_number(BufferTag* tag)
 	return hash % n_shards;
 }
 
-static void
-pageserver_sighup_handler(SIGNAL_ARGS)
-{
-	if (prev_signal_handler)
-	{
-        	prev_signal_handler(postgres_signal_arg);
-	}
-	neon_log(LOG, "Received SIGHUP, disconnecting pageserver. New pageserver connstring is %s", page_server_connstring);
-
-	 /* force refetching shard map */
-	LWLockAcquire(shard_map_lock, LW_EXCLUSIVE);
-	shard_map->n_shards = 0;
-	LWLockRelease(shard_map_lock);
-}
-
 static bool
 pageserver_connect(shardno_t shard_no, int elevel)
 {
@@ -251,7 +232,7 @@ pageserver_connect(shardno_t shard_no, int elevel)
 
 	Assert(page_servers[shard_no].conn == NULL);
 
-	(void)load_page_map(shard_no, connstr); /* refresh page map if needed */
+	(void)load_shard_map(shard_no, connstr); /* refresh page map if needed */
 
 	/*
 	 * Connect using the connection string we got from the
@@ -573,73 +554,12 @@ check_neon_id(char **newval, void **extra, GucSource source)
 	return **newval == '\0' || HexDecodeString(id, *newval, 16);
 }
 
-static Size
-PagestoreShmemSize(void)
-{
-	return sizeof(PagestoreShmemState);
-}
-
-static bool
-PagestoreShmemInit(void)
-{
-	bool		found;
-
-	LWLockAcquire(AddinShmemInitLock, LW_EXCLUSIVE);
-	pagestore_shared = ShmemInitStruct("libpagestore shared state",
-									   PagestoreShmemSize(),
-									   &found);
-	if (!found)
-	{
-		pagestore_shared->lock = &(GetNamedLWLockTranche("neon_libpagestore")->lock);
-		pg_atomic_init_u64(&pagestore_shared->update_counter, 0);
-		AssignPageserverConnstring(page_server_connstring, NULL);
-	}
-	LWLockRelease(AddinShmemInitLock);
-	return found;
-}
-
-static void
-pagestore_shmem_startup_hook(void)
-{
-	if (prev_shmem_startup_hook)
-		prev_shmem_startup_hook();
-
-	PagestoreShmemInit();
-}
-
-static void
-pagestore_shmem_request(void)
-{
-#if PG_VERSION_NUM >= 150000
-	if (prev_shmem_request_hook)
-		prev_shmem_request_hook();
-#endif
-
-	RequestAddinShmemSpace(PagestoreShmemSize());
-	RequestNamedLWLockTranche("neon_libpagestore", 1);
-}
-
-static void
-pagestore_prepare_shmem(void)
-{
-#if PG_VERSION_NUM >= 150000
-	prev_shmem_request_hook = shmem_request_hook;
-	shmem_request_hook = pagestore_shmem_request;
-#else
-	pagestore_shmem_request();
-#endif
-	prev_shmem_startup_hook = shmem_startup_hook;
-	shmem_startup_hook = pagestore_shmem_startup_hook;
-}
-
 /*
  * Module initialization function
  */
 void
 pg_init_libpagestore(void)
 {
-	pagestore_prepare_shmem();
-
 	DefineCustomStringVariable("neon.pageserver_connstring",
 							   "connection string to the page server",
 							   NULL,
@@ -647,7 +567,7 @@ pg_init_libpagestore(void)
 							   "",
 							   PGC_SIGHUP,
 							   0,	/* no flags required */
-							   CheckPageserverConnstring, AssignPageserverConnstring, NULL);
+							   NULL, AssignPageserverConnstring, NULL);
 
 	DefineCustomStringVariable("neon.timeline_id",
 							   "Neon timeline_id the server is running on",
diff --git a/pgxn/neon/pagestore_client.h b/pgxn/neon/pagestore_client.h
index b0d03c8cfc..c9c758c61d 100644
--- a/pgxn/neon/pagestore_client.h
+++ b/pgxn/neon/pagestore_client.h
@@ -27,6 +27,10 @@
 
 #include "pg_config.h"
 
+#define MAX_SHARDS 128
+#define STRIPE_SIZE (256 * 1024 / 8) /* TODO: should in betaken from control plane? */
+#define MAX_PS_CONNSTR_LEN 128
+
 typedef enum
 {
 	/* pagestore_client -> pagestore */