database/mariadb
1
0
Fork 0
mirror of https://github.com/MariaDB/server.git synced 2025-08-08 11:22:35 +03:00
Code Activity

[MDEV-28162] Replace PFS_atomic with std::atomic<T>

Browse Source 
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.
This commit is contained in:
Meng-Hsiu Chiang
2023-12-06 19:48:53 +00:00
committed by Marko Mäkelä
parent d5bad49011
commit 55db59f16d
18 changed files with 109 additions and 248 deletions
Download Patch File Download Diff File Expand all files Collapse all files

2
storage/perfschema/pfs_instr.cc
View File

@@ -526,7 +526,7 @@ PFS_thread* create_thread(PFS_thread_class *klass, const void *identity,
if (pfs != NULL)
{
pfs->m_thread_internal_id=
PFS_atomic::add_u64(&thread_internal_id_counter.m_u64, 1);
thread_internal_id_counter.m_u64.fetch_add(1);
pfs->m_parent_thread_internal_id= 0;
pfs->m_processlist_id= static_cast<ulong>(processlist_id);
pfs->m_thread_os_id= my_thread_os_id();