cond_signal.h

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/* PROLOG END TAG zYx                                              */
#ifndef _PPU_COND_SIGNAL_H_
#define _PPU_COND_SIGNAL_H_

#include <ppu_intrinsics.h>
#include "sync_utils.h"
#include "cond.h"

/*
 * _cond_signal: signaling any of the waiting threads to wake up.
 */ 
static __inline void _cond_signal (cond_ea_t cond)
{
  unsigned int val, waiting, signaled;
  void *p;

  SYNC_ULL_TO_PTR(cond, p);
  
  do {
    val = __lwarx(p);

    waiting = val & 0xFFFF;
    signaled = val >> 16;
    
    /* If no other party is waiting. Don't send a signal.
     * Otherwise, increment the signaled halfword.
     */
    if (waiting == signaled) break;
    val = ((val+1) << 16) | waiting;

  } while (__stwcx(p, val) == 0);
}


#endif /* _PPU_COND_SIGNAL_H_ */