gcc/libgcc/config/gthr-vxworks.c
Corentin Gay 806dd0472f Improve the thread support for VxWorks
2019-11-12  Corentin Gay  <gay@adacore.com>
	    Jerome Lambourg  <lambourg@adacore.com>
	    Olivier Hainque  <hainque@adacore.com>

	libgcc/

	* config/t-gthr-vxworks: New file, add all the gthr-vxworks
	sources to LIB2ADDEH.
	* config/t-vxworks: Remove adjustments to LIB2ADDEH.
	* config/t-vxworks7: Likewise.

	* config.host: Append a block at the end of the file to add the
	t-gthr files to the tmake_file list for VxWorks after everything
	else.

	* config/vxlib.c: Rename as gthr-vxworks.c.
	* config/vxlib-tls.c: Rename as gthr-vxworks-tls.c.

	* config/gthr-vxworks.h: Simplify a few comments.  Expose a TAS
	API and a basic error checking API, both internal.  Simplify the
	__gthread_once_t type definition and initializers.  Add sections
	for condition variables support and for the C++0x thread support,
	conditioned against Vx653 for the latter.

	* config/gthr-vxworks.c (__gthread_once): Simplify comments and
	implementation, leveraging the TAS internal API.
	* config/gthr-vxworks-tls.c: Introduce an internal TLS data access
	API, leveraging the general availability of TLS services in VxWorks7
	post SR6xxx.
	(__gthread_setspecific, __gthread_setspecific): Use it.
	(tls_delete_hook): Likewise, and simplify the enter/leave dtor logic.
	* config/gthr-vxworks-cond.c: New file.  GTHREAD_COND variable
	support based on VxWorks primitives.
	* config/gthr-vxworks-thread.c: New file.  GTHREAD_CXX0X support
	based on VxWorks primitives.

Co-Authored-By: Jerome Lambourg <lambourg@adacore.com>
Co-Authored-By: Olivier Hainque <hainque@adacore.com>

From-SVN: r278249
2019-11-14 15:58:31 +00:00

88 lines
2.3 KiB
C

/* Copyright (C) 2002-2019 Free Software Foundation, Inc.
Contributed by Zack Weinberg <zack@codesourcery.com>
This file is part of GCC.
GCC is free software; you can redistribute it and/or modify it under
the terms of the GNU General Public License as published by the Free
Software Foundation; either version 3, or (at your option) any later
version.
GCC 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 General Public License
for more details.
Under Section 7 of GPL version 3, you are granted additional
permissions described in the GCC Runtime Library Exception, version
3.1, as published by the Free Software Foundation.
You should have received a copy of the GNU General Public License and
a copy of the GCC Runtime Library Exception along with this program;
see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
<http://www.gnu.org/licenses/>. */
/* Threads compatibility routines for libgcc2 for VxWorks.
This file implements the init-once service exposed by gthr-vxworks.h. */
#include "tconfig.h"
#include "tsystem.h"
#include "gthr.h"
#if defined(__GTHREADS)
#include <vxWorks.h>
#ifndef __RTP__
# include <vxLib.h>
# include <taskHookLib.h>
#else /* __RTP__ */
# include <errno.h>
#endif /* __RTP__ */
/* ----------------------------- Init-once ------------------------------- */
static void
__release (__gthread_once_t ** __guard)
{
(*__guard)->busy = 0;
}
int
__gthread_once (__gthread_once_t * __guard, void (*__func) (void))
{
if (__guard->done)
return 0;
/* Busy-wait until we have exclusive access to the state. Check if
another thread managed to perform the init call in the interim. */
while (!__TAS(&__guard->busy))
{
if (__guard->done)
return 0;
taskDelay (1);
}
if (!__guard->done)
{
#ifndef __USING_SJLJ_EXCEPTIONS__
/* Setup a cleanup to release the guard when __func() throws an
exception. We cannot use this with SJLJ exceptions as
Unwind_Register calls __gthread_once, leading to an infinite
recursion. */
__attribute__ ((cleanup (__release)))
__gthread_once_t *__temp = __guard;
#endif
__func ();
__guard->done = 1;
}
__release(&__guard);
return 0;
}
#endif /* __GTHREADS */