MDEV-28313: Shrink ReadView::m_mutex

A few PERFORMANCE_SCHEMA instrumentation keys were not exposed
in all_innodb_mutexes[]. Let us remove them.

The keys fts_pll_tokenize_mutex_key and read_view_mutex_key were
internally used. Let us make ReadView::m_mutex use the simpler
and smaller srw_mutex, hoping to improve memory access patterns.

storage/innobase/handler/ha_innodb.cc

@@ -522,7 +522,6 @@ mysql_pfs_key_t	fts_cache_mutex_key;
 mysql_pfs_key_t	fts_cache_init_mutex_key;
 mysql_pfs_key_t	fts_delete_mutex_key;
 mysql_pfs_key_t	fts_doc_id_mutex_key;
-mysql_pfs_key_t	fts_pll_tokenize_mutex_key;
 mysql_pfs_key_t	ibuf_bitmap_mutex_key;
 mysql_pfs_key_t	ibuf_mutex_key;
 mysql_pfs_key_t	ibuf_pessimistic_insert_mutex_key;
@@ -544,9 +543,6 @@ mysql_pfs_key_t	trx_pool_manager_mutex_key;
 mysql_pfs_key_t	lock_wait_mutex_key;
 mysql_pfs_key_t	trx_sys_mutex_key;
 mysql_pfs_key_t	srv_threads_mutex_key;
-mysql_pfs_key_t	thread_mutex_key;
-mysql_pfs_key_t row_drop_list_mutex_key;
-mysql_pfs_key_t	read_view_mutex_key;
 
 /* all_innodb_mutexes array contains mutexes that are
 performance schema instrumented if "UNIV_PFS_MUTEX"

storage/innobase/include/read0types.h

 /*****************************************************************************
 
 Copyright (c) 1997, 2016, Oracle and/or its affiliates. All Rights Reserved.
-Copyright (c) 2018, 2021, MariaDB Corporation.
+Copyright (c) 2018, 2022, MariaDB Corporation.
 
 This program is free software; you can redistribute it and/or modify it under
 the terms of the GNU General Public License as published by the Free Software
@@ -28,12 +28,9 @@ Created 2/16/1997 Heikki Tuuri
 
 #include "dict0mem.h"
 #include "trx0types.h"
+#include "srw_lock.h"
 #include <algorithm>
 
-#ifdef UNIV_PFS_MUTEX
-extern mysql_pfs_key_t read_view_mutex_key;
-#endif
-
 /**
   Read view lists the trx ids of those transactions for which a consistent read
   should not see the modifications to the database.
@@ -44,7 +41,7 @@ class ReadViewBase
     The read should not see any transaction with trx id >= this value.
     In other words, this is the "high water mark".
   */
-  trx_id_t m_low_limit_id;
+  trx_id_t m_low_limit_id= 0;
 
   /**
     The read should see all trx ids which are strictly
@@ -70,9 +67,6 @@ class ReadViewBase
   trx_id_t up_limit_id() const { return m_up_limit_id; }
 
 public:
-  ReadViewBase(): m_low_limit_id(0) {}
-
-
   /**
     Append state from another view.
 
@@ -206,7 +200,7 @@ class ReadView: public ReadViewBase
   std::atomic<bool> m_open;
 
   /** For synchronisation with purge coordinator. */
-  mutable mysql_mutex_t m_mutex;
+  mutable srw_mutex m_mutex;
 
   /**
     trx id of creating transaction.
@@ -215,9 +209,12 @@ class ReadView: public ReadViewBase
   trx_id_t m_creator_trx_id;
 
 public:
-  ReadView(): m_open(false)
-  { mysql_mutex_init(read_view_mutex_key, &m_mutex, nullptr); }
-  ~ReadView() { mysql_mutex_destroy(&m_mutex); }
+  ReadView()
+  {
+    memset(reinterpret_cast<void*>(this), 0, sizeof *this);
+    m_mutex.init();
+  }
+  ~ReadView() { m_mutex.destroy(); }
 
 
   /**
@@ -265,12 +262,12 @@ class ReadView: public ReadViewBase
   */
   void print_limits(FILE *file) const
   {
-    mysql_mutex_lock(&m_mutex);
+    m_mutex.wr_lock();
     if (is_open())
       fprintf(file, "Trx read view will not see trx with"
                     " id >= " TRX_ID_FMT ", sees < " TRX_ID_FMT "\n",
                     low_limit_id(), up_limit_id());
-    mysql_mutex_unlock(&m_mutex);
+    m_mutex.wr_unlock();
   }
 
 
@@ -289,10 +286,10 @@ class ReadView: public ReadViewBase
   */
   void append_to(ReadViewBase *to) const
   {
-    mysql_mutex_lock(&m_mutex);
+    m_mutex.wr_lock();
     if (is_open())
       to->append(*this);
-    mysql_mutex_unlock(&m_mutex);
+    m_mutex.wr_unlock();
   }
 
   /**

storage/innobase/include/univ.i

@@ -540,7 +540,6 @@ extern mysql_pfs_key_t fts_cache_mutex_key;
 extern mysql_pfs_key_t fts_cache_init_mutex_key;
 extern mysql_pfs_key_t fts_delete_mutex_key;
 extern mysql_pfs_key_t fts_doc_id_mutex_key;
-extern mysql_pfs_key_t fts_pll_tokenize_mutex_key;
 extern mysql_pfs_key_t ibuf_bitmap_mutex_key;
 extern mysql_pfs_key_t ibuf_mutex_key;
 extern mysql_pfs_key_t ibuf_pessimistic_insert_mutex_key;
@@ -561,8 +560,6 @@ extern mysql_pfs_key_t trx_pool_mutex_key;
 extern mysql_pfs_key_t trx_pool_manager_mutex_key;
 extern mysql_pfs_key_t lock_wait_mutex_key;
 extern mysql_pfs_key_t srv_threads_mutex_key;
-extern mysql_pfs_key_t thread_mutex_key;
-extern mysql_pfs_key_t row_drop_list_mutex_key;
 # endif /* UNIV_PFS_MUTEX */
 
 # ifdef UNIV_PFS_RWLOCK

storage/innobase/read/read0read.cc

 /*****************************************************************************
 
 Copyright (c) 1996, 2015, Oracle and/or its affiliates. All Rights Reserved.
-Copyright (c) 2018, 2021, MariaDB Corporation.
+Copyright (c) 2018, 2022, MariaDB Corporation.
 
 This program is free software; you can redistribute it and/or modify it under
 the terms of the GNU General Public License as published by the Free Software
@@ -226,10 +226,10 @@ void ReadView::open(trx_t *trx)
       m_open.store(true, std::memory_order_relaxed);
     else
     {
-      mysql_mutex_lock(&m_mutex);
+      m_mutex.wr_lock();
       snapshot(trx);
       m_open.store(true, std::memory_order_relaxed);
-      mysql_mutex_unlock(&m_mutex);
+      m_mutex.wr_unlock();
     }
   }
 }

storage/innobase/row/row0ftsort.cc

 /*****************************************************************************
 
 Copyright (c) 2010, 2016, Oracle and/or its affiliates. All Rights Reserved.
-Copyright (c) 2015, 2021, MariaDB Corporation.
+Copyright (c) 2015, 2022, MariaDB Corporation.
 
 This program is free software; you can redistribute it and/or modify it under
 the terms of the GNU General Public License as published by the Free Software
@@ -285,8 +285,7 @@ row_fts_psort_info_init(
 		psort_info[j].psort_common = common_info;
 		psort_info[j].error = DB_SUCCESS;
 		psort_info[j].memory_used = 0;
-		mysql_mutex_init(fts_pll_tokenize_mutex_key,
-				 &psort_info[j].mutex, nullptr);
+		mysql_mutex_init(0, &psort_info[j].mutex, nullptr);
 	}
 
 	/* Initialize merge_info structures parallel merge and insert