80 lines
2.3 KiB
C
80 lines
2.3 KiB
C
/* Copyright (C) 2005-2019 Free Software Foundation, Inc.
|
|
Contributed by Jakub Jelinek <jakub@redhat.com>.
|
|
|
|
This file is part of the GNU Offloading and Multi Processing Library
|
|
(libgomp).
|
|
|
|
Libgomp 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.
|
|
|
|
Libgomp 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/>. */
|
|
|
|
/* Provide target-specific access to the futex system call. */
|
|
|
|
#include <sys/syscall.h>
|
|
|
|
static inline long
|
|
sys_futex0 (int *addr, int op, int val)
|
|
{
|
|
register long int gpr2 __asm__ ("2");
|
|
register long int gpr3 __asm__ ("3");
|
|
register long int gpr4 __asm__ ("4");
|
|
register long int gpr5 __asm__ ("5");
|
|
|
|
gpr2 = (long) addr;
|
|
gpr3 = op;
|
|
gpr4 = val;
|
|
gpr5 = 0;
|
|
|
|
__asm volatile ("svc %b1"
|
|
: "=d" (gpr2)
|
|
: "i" (SYS_futex),
|
|
"0" (gpr2), "d" (gpr3), "d" (gpr4), "d" (gpr5)
|
|
: "memory");
|
|
return gpr2;
|
|
}
|
|
|
|
static inline void
|
|
futex_wait (int *addr, int val)
|
|
{
|
|
long err = sys_futex0 (addr, gomp_futex_wait, val);
|
|
if (__builtin_expect (err == -ENOSYS, 0))
|
|
{
|
|
gomp_futex_wait &= ~FUTEX_PRIVATE_FLAG;
|
|
gomp_futex_wake &= ~FUTEX_PRIVATE_FLAG;
|
|
sys_futex0 (addr, gomp_futex_wait, val);
|
|
}
|
|
}
|
|
|
|
static inline void
|
|
futex_wake (int *addr, int count)
|
|
{
|
|
long err = sys_futex0 (addr, gomp_futex_wake, count);
|
|
if (__builtin_expect (err == -ENOSYS, 0))
|
|
{
|
|
gomp_futex_wait &= ~FUTEX_PRIVATE_FLAG;
|
|
gomp_futex_wake &= ~FUTEX_PRIVATE_FLAG;
|
|
sys_futex0 (addr, gomp_futex_wake, count);
|
|
}
|
|
}
|
|
|
|
static inline void
|
|
cpu_relax (void)
|
|
{
|
|
__asm volatile ("" : : : "memory");
|
|
}
|