TSAN: unprotected global variable

  Write of size 1 at 0x0000067abe08 by thread T3 (mutexes: write M1372):
    #0 buf_flush_page_cleaner() /storage/innobase/buf/buf0flu.cc:2366:29 (mariadbd+0x20cea7c)
    #1 void std::__invoke_impl<void, void (*)()>(std::__invoke_other, void (*&&)()) /usr/lib/gcc/x86_64-linux-gnu/11/../../../../include/c++/11/bits/invoke.h:61:14 (mariadbd+0x20c3a8a)
    #2 std::__invoke_result<void (*)()>::type std::__invoke<void (*)()>(void (*&&)()) /usr/lib/gcc/x86_64-linux-gnu/11/../../../../include/c++/11/bits/invoke.h:96:14 (mariadbd+0x20c399d)
    #3 void std::thread::_Invoker<std::tuple<void (*)()> >::_M_invoke<0ul>(std::_Index_tuple<0ul>) /usr/lib/gcc/x86_64-linux-gnu/11/../../../../include/c++/11/bits/std_thread.h:253:13 (mariadbd+0x20c3945)
    #4 std::thread::_Invoker<std::tuple<void (*)()> >::operator()() /usr/lib/gcc/x86_64-linux-gnu/11/../../../../include/c++/11/bits/std_thread.h:260:11 (mariadbd+0x20c38e5)
    #5 std::thread::_State_impl<std::thread::_Invoker<std::tuple<void (*)()> > >::_M_run() /usr/lib/gcc/x86_64-linux-gnu/11/../../../../include/c++/11/bits/std_thread.h:211:13 (mariadbd+0x20c37d9)
    #6 <null> <null> (libstdc++.so.6+0xd230f)

  Previous read of size 1 at 0x0000067abe08 by main thread:
    #0 logs_empty_and_mark_files_at_shutdown() /storage/innobase/log/log0log.cc:1094:6 (mariadbd+0x22eeff3)
    #1 innodb_shutdown() /storage/innobase/srv/srv0start.cc:1970:3 (mariadbd+0x256ffd6)
    #2 innobase_end(handlerton*, ha_panic_function) /storage/innobase/handler/ha_innodb.cc:4265:3 (mariadbd+0x1ee3fc4)
    #3 ha_finalize_handlerton(st_plugin_int*) /sql/handler.cc:595:5 (mariadbd+0xf7bac9)
    #4 plugin_deinitialize(st_plugin_int*, bool) /sql/sql_plugin.cc:1266:9 (mariadbd+0x1611789)
    #5 reap_plugins() /sql/sql_plugin.cc:1342:7 (mariadbd+0x160e17d)
    #6 plugin_shutdown() /sql/sql_plugin.cc:2050:7 (mariadbd+0x1611f42)
    #7 clean_up(bool) /sql/mysqld.cc:1923:3 (mariadbd+0xd67a4c)
    MariaDB#8 unireg_abort /sql/mysqld.cc:1835:3 (mariadbd+0xd67605)
    MariaDB#9 mysqld_main(int, char**) /sql/mysqld.cc:5741:7 (mariadbd+0xd6b36a)
    MariaDB#10 main /sql/main.cc:34:10 (mariadbd+0xd661a8)

  Location is global 'buf_page_cleaner_is_active' of size 1 at 0x0000067abe08 (mariadbd+0x67abe08)

storage/innobase/buf/buf0flu.cc

@@ -57,7 +57,7 @@ ulint buf_lru_freed_page_count;
 ulint buf_flush_page_count;
 
 /** Flag indicating if the page_cleaner is in active state. */
-bool buf_page_cleaner_is_active;
+Atomic_relaxed<bool> buf_page_cleaner_is_active;
 
 /** Factor for scan length to determine n_pages for intended oldest LSN
 progress */

storage/innobase/include/buf0flu.h

@@ -40,7 +40,7 @@ extern ulint buf_lru_flush_page_count;
 extern ulint buf_lru_freed_page_count;
 
 /** Flag indicating if the page_cleaner is in active state. */
-extern bool buf_page_cleaner_is_active;
+extern Atomic_relaxed<bool> buf_page_cleaner_is_active;
 
 #ifdef UNIV_DEBUG