[thirdparty/gcc.git] / libgomp / config / linux / s390 / futex.h

/* Copyright (C) 2005-2023 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");
}
Commit	Line	Data
	1	/* Copyright (C) 2005-2023 Free Software Foundation, Inc.
	2	Contributed by Jakub Jelinek <jakub@redhat.com>.
	3
	4	This file is part of the GNU Offloading and Multi Processing Library
	5	(libgomp).
	6
	7	Libgomp is free software; you can redistribute it and/or modify it
	8	under the terms of the GNU General Public License as published by
	9	the Free Software Foundation; either version 3, or (at your option)
	10	any later version.
	11
	12	Libgomp is distributed in the hope that it will be useful, but WITHOUT ANY
	13	WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
	14	FOR A PARTICULAR PURPOSE. See the GNU General Public License for
	15	more details.
	16
	17	Under Section 7 of GPL version 3, you are granted additional
	18	permissions described in the GCC Runtime Library Exception, version
	19	3.1, as published by the Free Software Foundation.
	20
	21	You should have received a copy of the GNU General Public License and
	22	a copy of the GCC Runtime Library Exception along with this program;
	23	see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
	24	<http://www.gnu.org/licenses/>. */
	25
	26	/* Provide target-specific access to the futex system call. */
	27
	28	#include <sys/syscall.h>
	29
	30	static inline long
	31	sys_futex0 (int *addr, int op, int val)
	32	{
	33	register long int gpr2 __asm__ ("2");
	34	register long int gpr3 __asm__ ("3");
	35	register long int gpr4 __asm__ ("4");
	36	register long int gpr5 __asm__ ("5");
	37
	38	gpr2 = (long) addr;
	39	gpr3 = op;
	40	gpr4 = val;
	41	gpr5 = 0;
	42
	43	__asm volatile ("svc %b1"
	44	: "=d" (gpr2)
	45	: "i" (SYS_futex),
	46	"0" (gpr2), "d" (gpr3), "d" (gpr4), "d" (gpr5)
	47	: "memory");
	48	return gpr2;
	49	}
	50
	51	static inline void
	52	futex_wait (int *addr, int val)
	53	{
	54	long err = sys_futex0 (addr, gomp_futex_wait, val);
	55	if (__builtin_expect (err == -ENOSYS, 0))
	56	{
	57	gomp_futex_wait &= ~FUTEX_PRIVATE_FLAG;
	58	gomp_futex_wake &= ~FUTEX_PRIVATE_FLAG;
	59	sys_futex0 (addr, gomp_futex_wait, val);
	60	}
	61	}
	62
	63	static inline void
	64	futex_wake (int *addr, int count)
	65	{
	66	long err = sys_futex0 (addr, gomp_futex_wake, count);
	67	if (__builtin_expect (err == -ENOSYS, 0))
	68	{
	69	gomp_futex_wait &= ~FUTEX_PRIVATE_FLAG;
	70	gomp_futex_wake &= ~FUTEX_PRIVATE_FLAG;
	71	sys_futex0 (addr, gomp_futex_wake, count);
	72	}
	73	}
	74
	75	static inline void
	76	cpu_relax (void)
	77	{
	78	__asm volatile ("" : : : "memory");
	79	}