spinlock.c

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/*****************************************************************************************
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 $Id: spinlock_8c-source.html 88 2016-01-12 00:11:29Z reddawg $

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

#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)
        sched_yield();
  }
}

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


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

 
/***
 END
 ***/

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