glibc/misc/single_threaded.c
Adhemerval Zanella baf2a265c7 misc: Optimize internal usage of __libc_single_threaded
By adding an internal alias to avoid the GOT indirection.
On some architecture, __libc_single_thread may be accessed through
copy relocations and thus it requires to update also the copies
default copy.

This is done by adding a new internal macro,
libc_hidden_data_{proto,def}, which has an addition argument that
specifies the alias name (instead of default __GI_ one).

Checked on x86_64-linux-gnu and i686-linux-gnu.

Reviewed-by: Fangrui Song <maskray@google.com>
2022-06-24 17:45:58 -03:00

30 lines
1.2 KiB
C

/* Support for single-thread optimizations. Statically linked version.
Copyright (C) 2020-2022 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<https://www.gnu.org/licenses/>. */
#include <sys/single_threaded.h>
/* In dynamically linked programs, this variable is initialized in
__libc_early_init (as false for inner libcs). */
#ifdef SHARED
char __libc_single_threaded;
#else
char __libc_single_threaded = 1;
#endif
libc_hidden_data_def_alias (__libc_single_threaded,
__libc_single_threaded_internal)