PFS_atomic class contains wrappers around my_atomic_* operations, which
are macros to GNU atomic operations (__atomic_*). Due to different
implementations of compilers, clang may encounter errors when compiling
on x86_32 architecture.
The following functions are replaced with C++ std::atomic type in
performance schema code base:
- PFS_atomic::store_*()
-> my_atomic_store*
-> __atomic_store_n()
=> std::atomic<T>::store()
- PFS_atomic::load_*()
-> my_atomic_load*
-> __atomic_load_n()
=> std::atomic<T>::load()
- PFS_atomic::add_*()
-> my_atomic_add*
-> __atomic_fetch_add()
=> std::atomic<T>::fetch_add()
- PFS_atomic::cas_*()
-> my_atomic_cas*
-> __atomic_compare_exchange_n()
=> std::atomic<T>::compare_exchange_strong()
and PFS_atomic class could be dropped completely.
Note that in the wrapper memory order passed to original GNU atomic
extensions are hard-coded as `__ATOMIC_SEQ_CST`, which is equivalent to
`std::memory_order_seq_cst` in C++, and is the default parameter for
std::atomic_* functions.
All new code of the whole pull request, including one or several files
that are either new files or modified ones, are contributed under the
BSD-new license. I am contributing on behalf of my employer Amazon Web
Services.
Some places didn't match the previous rules, making the Floor
address wrong.
Additional sed rules:
sed -i -e 's/Place.*Suite .*, Boston/Street, Fifth Floor, Boston/g'
sed -i -e 's/Suite .*, Boston/Fifth Floor, Boston/g'
client/mysql_upgrade.c:
missing DBUG_RETURN
client/mysqladmin.cc:
client plugin memory wasn't freed
client/mysqlcheck.c:
client plugin memory, defaults, a result set, a command-line option value were not freed.
missing DBUG_RETURN.
client/mysqldump.c:
client plugin memory wasn't freed
client/mysqlslap.c:
client plugin memory wasn't freed
client/mysqltest.cc:
hopeless. cannot be fixed.
mysql-test/valgrind.supp:
Bug#56666 is now fixed.
mysys/array.c:
really, don't allocate if the caller didn't ask to.
mysys/my_init.c:
safemalloc checks must be done at the very end
mysys/my_thr_init.c:
not needed anymore
sql-common/client.c:
memory leak
sql/log.cc:
log_file was not closed, memory leak.
sql/mysqld.cc:
fix bug#56666 (causing many P_S related memory leaks).
close_active_mi() not called for --bootstrap, memory leak.
sql/sql_lex.cc:
redo Lex->mi handling
sql/sql_lex.h:
redo Lex->mi handling
sql/sql_plugin.cc:
plugins having PLUGIN_VAR_MEMALLOC string variables have this variables allocated in every THD.
The memory was freed in ~THD but only if plugin was still active. If plugin was unloaded the
variable was not found and the memory was lost. By loading and unloading plugins an arbitrary
amount of memory can be lost.
sql/sql_repl.cc:
redo Lex->mi handling
sql/sql_yacc.yy:
completely wrong handling of Lex->mi - run-time memory leak, by repeating the statement
arbitrary amount of memory can be lost.
Lex->mi.repl_ignore_server_ids_opt was allocated when parsing CHANGE MASTER,
and freed after executing the statement. if parser failed on syntax (or another)
error the statement was never executed. Lex->mi was simply bzero-ed for the next
CHANGE MASTER statement.
sql/table.cc:
didn't compile
storage/perfschema/pfs_lock.h:
Bug#56666 is fixed
Before this fix, an assert could fail in PFS_lock::allocated_to_free(), during shutdown.
The assert itself is valid, and detects an anomaly caused by bug 56666.
While bug 56666 has no real consequences in production,
the failure caused by this new assert in the code is negatively
impacting the test suite with automated tests.
This fix is a work around only, that relaxes the integrity checks
during the server shutdown.
