nptl: Add C11 threads call_once functions

This patch adds the call_* definitions from C11 threads (ISO/IEC 9899:2011),
more specifically call_once and required types.

Mostly of the definitions are composed based on POSIX conterparts,including
once_flag (pthread_once_t).  The idea is to make possible to share POSIX
internal implementations for mostly of the code (and making adjustment only
when required).

Checked with a build for all major ABI (aarch64-linux-gnu, alpha-linux-gnu,
arm-linux-gnueabi, i386-linux-gnu, ia64-linux-gnu, m68k-linux-gnu,
microblaze-linux-gnu [1], mips{64}-linux-gnu, nios2-linux-gnu,
powerpc{64le}-linux-gnu, s390{x}-linux-gnu, sparc{64}-linux-gnu,
and x86_64-linux-gnu).

Also ran a full check on aarch64-linux-gnu, x86_64-linux-gnu, i686-linux-gnu,
arm-linux-gnueabhf, and powerpc64le-linux-gnu.

	[BZ #14092]
	* conform/data/threads.h-data (ONCE_FLAG_INIT): New macro.
	(once_flag): New type.
	(call_once): New function.
	* nptl/Makefile (libpthread-routines): Add call_once object.
	* nptl/Versions (libphread) [GLIBC_2.28]: Add call_once symbol.
	* nptl/call_once.c: New file.
	* sysdeps/nptl/threads.h (ONCE_FLAG_INIT): New define.
	(once_flag): New type.
	(call_once): New prototype.
This commit is contained in:
Adhemerval Zanella 2017-06-27 10:49:51 -03:00
parent 18d59c1b36
commit 3c20a679b6
6 changed files with 60 additions and 1 deletions

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@ -1,5 +1,16 @@
2018-07-24 Adhemerval Zanella <adhemerval.zanella@linaro.org>
[BZ #14092]
* conform/data/threads.h-data (ONCE_FLAG_INIT): New macro.
(once_flag): New type.
(call_once): New function.
* nptl/Makefile (libpthread-routines): Add call_once object.
* nptl/Versions (libphread) [GLIBC_2.28]: Add call_once symbol.
* nptl/call_once.c: New file.
* sysdeps/nptl/threads.h (ONCE_FLAG_INIT): New define.
(once_flag): New type.
(call_once): New prototype.
[BZ #14092]
* conform/data/threads.h-data (mtx_plain): New constant.
(mtx_recursive): Likewise.

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@ -1,5 +1,7 @@
#if defined ISO11
macro ONCE_FLAG_INIT
constant thrd_success
constant thrd_busy
constant thrd_error
@ -13,6 +15,7 @@ constant mtx_timed
type thrd_t
type thrd_start_t
type mtx_t
type once_flag
function int thrd_create (thrd_t*, thrd_start_t, void*)
function int thrd_equal (thrd_t, thrd_t)
@ -30,6 +33,8 @@ function int mtx_trylock (mtx_t*)
function int mtx_unlock (mtx_t*)
function void mtx_destroy (mtx_t*)
function void call_once (once_flag*, void (*)(void))
#include "time.h-data"
#endif

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@ -143,7 +143,7 @@ libpthread-routines = nptl-init nptlfreeres vars events version pt-interp \
pthread_setattr_default_np pthread_getattr_default_np \
thrd_create thrd_detach thrd_exit thrd_join \
mtx_destroy mtx_init mtx_lock mtx_timedlock \
mtx_trylock mtx_unlock
mtx_trylock mtx_unlock call_once
# pthread_setuid pthread_seteuid pthread_setreuid \
# pthread_setresuid \
# pthread_setgid pthread_setegid pthread_setregid \

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@ -273,6 +273,7 @@ libpthread {
GLIBC_2.28 {
thrd_create; thrd_detach; thrd_exit; thrd_join;
mtx_init; mtx_lock; mtx_timedlock; mtx_trylock; mtx_unlock; mtx_destroy;
call_once;
}
GLIBC_PRIVATE {

31
nptl/call_once.c Normal file
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@ -0,0 +1,31 @@
/* C11 threads call once implementation.
Copyright (C) 2018 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
<http://www.gnu.org/licenses/>. */
#include <stdalign.h>
#include "thrd_priv.h"
void
call_once (once_flag *flag, void (*func)(void))
{
_Static_assert (sizeof (once_flag) == sizeof (pthread_once_t),
"sizeof (once_flag) != sizeof (pthread_once_t)");
_Static_assert (alignof (once_flag) == alignof (pthread_once_t),
"alignof (once_flag) != alignof (pthread_once_t)");
__pthread_once (&flag->__data, func);
}

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@ -48,6 +48,12 @@ enum
mtx_timed = 2
};
typedef struct
{
int __data __ONCE_ALIGNMENT;
} once_flag;
#define ONCE_FLAG_INIT { 0 }
typedef union
{
char __size[__SIZEOF_PTHREAD_MUTEX_T];
@ -129,6 +135,11 @@ extern int mtx_unlock (mtx_t *__mutex);
/* Destroy the mutex object pointed by __MUTEX. */
extern void mtx_destroy (mtx_t *__mutex);
/* Call function __FUNC exactly once, even if invoked from several threads.
All calls must be made with the same __FLAGS object. */
extern void call_once (once_flag *__flag, void (*__func)(void));
__END_DECLS
#endif /* _THREADS_H */