88 lines
2.7 KiB
C
88 lines
2.7 KiB
C
|
/* Copyright (C) 2005-2021 Free Software Foundation, Inc.
|
||
|
|
Contributed by Richard Henderson <rth@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 r0 __asm__ ("r0");
|
||
|
|
register long int r3 __asm__ ("r3");
|
||
|
|
register long int r4 __asm__ ("r4");
|
||
|
|
register long int r5 __asm__ ("r5");
|
||
|
|
register long int r6 __asm__ ("r6");
|
||
|
|
|
||
|
|
r0 = SYS_futex;
|
||
|
|
r3 = (long) addr;
|
||
|
|
r4 = op;
|
||
|
|
r5 = val;
|
||
|
|
r6 = 0;
|
||
|
|
|
||
|
|
/* ??? The powerpc64 sysdep.h file clobbers ctr; the powerpc32 sysdep.h
|
||
|
|
doesn't. It doesn't much matter for us. In the interest of unity,
|
||
|
|
go ahead and clobber it always. */
|
||
|
|
|
||
|
|
__asm volatile ("sc; mfcr %0"
|
||
|
|
: "=r"(r0), "=r"(r3), "=r"(r4), "=r"(r5), "=r"(r6)
|
||
|
|
: "r"(r0), "r"(r3), "r"(r4), "r"(r5), "r"(r6)
|
||
|
|
: "r7", "r8", "r9", "r10", "r11", "r12",
|
||
|
|
"cr0", "ctr", "memory");
|
||
|
|
if (__builtin_expect (r0 & (1 << 28), 0))
|
||
|
|
return r3;
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
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");
|
||
|
|
}
|