/*****************************************************************************************
 Copyright (c) 2002-2004 The UbixOS Project
 All rights reserved.

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 contributors may be used to endorse or promote products derived from this software
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 $Id$

*****************************************************************************************/

#include <ubixos/spinlock.h>
#include <ubixos/sched.h>

void spinLockInit(spinLock_t *lock) {
  *lock = SPIN_LOCK_INITIALIZER;
  }

void spinUnlock(spinLock_t *lock) {
  *lock = 0x0;
  /*
  register int unlocked;
  asm volatile(
    "xchgl %0, %1"
    : "=&r" (unlocked), "=m" (*lock) : "0" (0)
    );
  */
  }

int spinTryLock(spinLock_t *lock) {
  register int locked;
  asm volatile("xchgl %0, %1"
    : "=&r" (locked), "=m" (*lock) : "0" (1)
    );
  return(!locked);
  }

void spinLock(spinLock_t *lock) {
  while (!spinTryLock(lock))
    while (*lock == 1)
      schedYield();
  }

int spinLockLocked(spinLock_t *lock) {
  return(*lock != 0);
  }

 
/***
 $Log$
 Revision 1.11  2004/07/21 17:11:18  reddawg
 A Quick tweak I'm going to clean up some unused variables in sched.h

 Revision 1.10  2004/07/20 21:17:05  reddawg
 CFLAGS: I updated cflags so optimizations are consistant on all files different optimization levels maybe the source of some of our problems?

 Revision 1.9  2004/07/20 20:25:57  reddawg
 Works perfectly here

 Revision 1.8  2004/07/20 20:20:19  reddawg
 spinlock: made them non inline functions I think this actually fixed the problem

 Revision 1.7  2004/07/18 05:24:15  reddawg
 Fixens

 Revision 1.6  2004/07/18 03:01:44  reddawg
 Few changes to spinlock hopefully it will cure our deadlock

 Revision 1.5  2004/07/17 16:43:10  reddawg
 shell: fixed stress testing
 ubistry: fixed some segfaults
 spinlock: added assert()

 Revision 1.4  2004/05/21 12:42:32  reddawg
 Cleaned Up

 Revision 1.3  2004/05/15 02:30:28  reddawg
 Lots of changes

 Revision 1.2  2004/05/02 14:34:21  reddawg
 SMP Support Thanks To Some Help From Slowcoder now to make it interface
 well with the rest of the kernel

 Revision 1.1  2004/05/02 03:19:51  reddawg
 Added Spinlock Provision For SMP

 END
 ***/