Skip to content

opal: disable the __atomic built-in atomics by default on AArch64 #8413

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
rajachan merged 1 commit into from
Jan 25, 2021
Merged

opal: disable the __atomic built-in atomics by default on AArch64 #8413

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
4 changes: 3 additions & 1 deletion NEWS
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -22,8 +22,9 @@ Copyright (c) 2013 NVIDIA Corporation. All rights reserved.
Copyright (c) 2013-2018 Intel, Inc. All rights reserved.
Copyright (c) 2018-2020 Amazon.com, Inc. or its affiliates. All Rights
reserved.
Copyright (c) 2019-2020 Triad National Security, LLC. All rights
Copyright (c) 2019-2021 Triad National Security, LLC. All rights
reserved.
Copyright (c) 2021 Google, LLC. All rights reserved.
$COPYRIGHT$

Additional copyrights may follow
Expand Down Expand Up @@ -103,6 +104,7 @@ included in the vX.Y.Z section and be denoted as:
- OFI/libfabric: Added btl for one-sided support
- OFI/libfabric: Multiple small bugfixes
- libnbc: Adding numerous performance-improving algorithms
- AArch64: disable gcc built-in atomics by default.

4.0.5 -- August, 2020
---------------------
Expand Down
9 changes: 8 additions & 1 deletion config/opal_config_asm.m4
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -17,6 +17,7 @@ dnl Copyright (c) 2014-2017 Los Alamos National Security, LLC. All rights
dnl reserved.
dnl Copyright (c) 2017 Amazon.com, Inc. or its affiliates. All Rights
dnl reserved.
dnl Copyright (c) 2021 Google, LLC. All rights reserved.
dnl $COPYRIGHT$
dnl
dnl Additional copyrights may follow
Expand Down Expand Up @@ -1022,7 +1023,7 @@ AC_DEFUN([OPAL_CONFIG_ASM],[

AC_ARG_ENABLE([builtin-atomics],
[AC_HELP_STRING([--enable-builtin-atomics],
[Enable use of __sync builtin atomics (default: enabled)])])
[Enable use of __atomic builtin atomics (default: enabled)])])

opal_cv_asm_builtin="BUILTIN_NO"
AS_IF([test "$opal_cv_asm_builtin" = "BUILTIN_NO" && test "$enable_builtin_atomics" != "no"],
Expand Down Expand Up @@ -1075,6 +1076,12 @@ AC_DEFUN([OPAL_CONFIG_ASM],[
OPAL_ASM_ARM_VERSION=8
AC_DEFINE_UNQUOTED([OPAL_ASM_ARM_VERSION], [$OPAL_ASM_ARM_VERSION],
[What ARM assembly version to use])
# If built-in atomics were not specifically request then disable the
# use of built-in atomics. The performance of Open MPI when using the
# built-ins is worse than when they are not in use.
if test "$enable_builtin_atomics" != "yes" ; then
opal_cv_asm_builtin="BUILTIN_NO"
fi
OPAL_GCC_INLINE_ASSIGN='"mov %0, #0" : "=&r"(ret)'
;;

Expand Down