glibc/nptl/sysdeps/unix/sysv/linux/sh/lowlevellock.h

/* Copyright (C) 2003 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, write to the Free
   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
   02111-1307 USA.  */

#ifndef _LOWLEVELLOCK_H
#define _LOWLEVELLOCK_H	1

#include <time.h>
#include <sys/param.h>
#include <bits/pthreadtypes.h>

#define SYS_futex		240
#define FUTEX_WAIT		0
#define FUTEX_WAKE		1


/* Initializer for compatibility lock.  */
#define LLL_MUTEX_LOCK_INITIALIZER (0)

extern int __lll_mutex_lock_wait (int val, int *__futex) attribute_hidden;
extern int __lll_mutex_timedlock_wait (int val, int *__futex,
				       const struct timespec *abstime)
     attribute_hidden;
extern int __lll_mutex_unlock_wake (int *__futex) attribute_hidden;


#define lll_mutex_trylock(futex) \
  ({ unsigned char __result; \
     __asm __volatile ("\
	.align 2\n\
	mova 1f,r0\n\
	nop\n\
	mov r15,r1\n\
	mov #-8,r15\n\
     0: mov.l @%1,r2\n\
	cmp/eq r2,%3\n\
	bf 1f\n\
	mov.l %2,@%1\n\
     1: mov r1,r15\n\
	mov #-1,%0\n\
	negc %0,%0"\
	: "=r" (__result) : "r" (&(futex)), "r" (1), "r" (0) \
	: "r0", "r1", "r2", "t", "memory"); \
     __result; })

#define lll_mutex_lock(futex) \
  (void) ({ int __result, val, *__futex = &(futex); \
	    __asm __volatile ("\
		.align 2\n\
		mova 1f,r0\n\
		mov r15,r1\n\
		mov #-6,r15\n\
	     0: mov.l @%2,%0\n\
		add %0,%1\n\
		mov.l %1,@%2\n\
	     1: mov r1,r15"\
		: "=&r" (__result), "=&r" (val) : "r" (__futex), "1" (1) \
		: "r0", "r1", "memory"); \
	    if (__result) \
	      __lll_mutex_lock_wait (__result, __futex); })

#define lll_mutex_timedlock(futex, timeout) \
  ({ int __result, val, *__futex = &(futex); \
     __asm __volatile ("\
	.align 2\n\
	mova 1f,r0\n\
	mov r15,r1\n\
	mov #-6,r15\n\
     0: mov.l @%2,%0\n\
	add %0,%1\n\
	mov.l %1,@%2\n\
     1: mov r1,r15"\
	: "=&r" (__result), "=&r" (val) : "r" (__futex), "1" (1) \
	: "r0", "r1", "memory"); \
    if (__result) \
      __result = __lll_mutex_timedlock_wait (__result, __futex, timeout); \
    __result; })

#define lll_mutex_unlock(futex) \
  (void) ({ int __result, *__futex = &(futex); \
	    __asm __volatile ("\
		.align 2\n\
		mova 1f,r0\n\
		mov r15,r1\n\
		mov #-6,r15\n\
	     0: mov.l @%1,%0\n\
		add #-1,%0\n\
		mov.l %0,@%1\n\
	     1: mov r1,r15"\
		: "=&r" (__result) : "r" (__futex) \
		: "r0", "r1", "memory"); \
	    if (__result) \
	      __lll_mutex_unlock_wake (__futex); })

#define lll_mutex_islocked(futex) \
  (futex != 0)


/* We have a separate internal lock implementation which is not tied
   to binary compatibility.  */

/* Type for lock object.  */
typedef int lll_lock_t;

/* Initializers for lock.  */
#define LLL_LOCK_INITIALIZER		(1)
#define LLL_LOCK_INITIALIZER_LOCKED	(0)


extern int __lll_lock_wait (int val, int *__futex) attribute_hidden;
extern int __lll_unlock_wake (int *__futex) attribute_hidden;
extern int lll_unlock_wake_cb (int *__futex) attribute_hidden;


/* The states of a lock are:
    1  -  untaken
    0  -  taken by one user
   <0  -  taken by more users */


#define lll_trylock(futex) \
  ({ unsigned char __result; \
     __asm __volatile ("\
	.align 2\n\
	mova 1f,r0\n\
	nop\n\
	mov r15,r1\n\
	mov #-8,r15\n\
     0: mov.l @%1,r2\n\
	cmp/eq r2,%3\n\
	bf 1f\n\
	mov.l %2,@%1\n\
     1: mov r1,r15\n\
	mov #-1,%0\n\
	negc %0,%0"\
	: "=r" (__result) : "r" (&(futex)), "r" (0), "r" (1) \
	: "r0", "r1", "r2", "t", "memory"); \
     __result; })

#define lll_lock(futex) \
  (void) ({ int __result, val, *__futex = &(futex); \
	    __asm __volatile ("\
		.align 2\n\
		mova 1f,r0\n\
		mov r15,r1\n\
		mov #-6,r15\n\
	     0: mov.l @%2,%0\n\
		add %0,%1\n\
		mov.l %1,@%2\n\
	     1: mov r1,r15"\
		: "=&r" (__result), "=&r" (val) : "r" (__futex), "1" (-1) \
		: "r0", "r1", "memory"); \
	    if (val < 0) \
	      __lll_lock_wait (__result, __futex); })

#define lll_unlock(futex) \
  (void) ({ int __result, *__futex = &(futex); \
	    __asm __volatile ("\
		.align 2\n\
		mova 1f,r0\n\
		mov r15,r1\n\
		mov #-6,r15\n\
	     0: mov.l @%1,%0\n\
		add #1,%0\n\
		mov.l %0,@%1\n\
	     1: mov r1,r15"\
		: "=&r" (__result) : "r" (__futex) \
		: "r0", "r1", "memory"); \
	    if (__result <= 0) \
	      __lll_unlock_wake (__futex); })

#define lll_islocked(futex) \
  (futex <= 0)


/* The kernel notifies a process with uses CLONE_CLEARTID via futex
   wakeup when the clone terminates.  The memory location contains the
   thread ID while the clone is running and is reset to zero
   afterwards.  */

extern int __lll_wait_tid (int *tid) attribute_hidden;
#define lll_wait_tid(tid) \
  do { \
    __typeof (tid) *__tid = &(tid); \
    if (*__tid != 0) \
      __lll_wait_tid (__tid); \
  } while (0)

extern int __lll_timedwait_tid (int *tid, const struct timespec *abstime)
     attribute_hidden;
#define lll_timedwait_tid(tid, abstime) \
  ({ \
    int __result = 0; \
    if (tid != 0) \
      {	\
	if (abstime == NULL || abstime->tv_nsec >= 1000000000) \
	  __result = EINVAL; \
	else \
	  __result = __lll_timedwait_tid (&tid, abstime); \
      }	\
    __result; })


/* Conditional variable handling.  */

extern void __lll_cond_wait (pthread_cond_t *cond) attribute_hidden;
extern int __lll_cond_timedwait (pthread_cond_t *cond,
				 const struct timespec *abstime)
     attribute_hidden;
extern void __lll_cond_wake (pthread_cond_t *cond) attribute_hidden;
extern void __lll_cond_broadcast (pthread_cond_t *cond) attribute_hidden;


#define lll_cond_wait(cond) \
  __lll_cond_wait (cond)
#define lll_cond_timedwait(cond, abstime) \
  __lll_cond_timedwait (cond, abstime)
#define lll_cond_wake(cond) \
  __lll_cond_wake (cond)
#define lll_cond_broadcast(cond) \
  __lll_cond_broadcast (cond)

#endif  /* lowlevellock.h */