gonzui

    1: /*
    2:  *----------------------------------------------------------------------
    3:  *    micro T-Kernel 3.00.00
    4:  *
    5:  *    Copyright (C) 2006-2019 by Ken Sakamura.
    6:  *    This software is distributed under the T-License 2.1.
    7:  *----------------------------------------------------------------------
    8:  *
    9:  *    Released by TRON Forum(http://www.tron.org) at 2019/12/11.
   10:  *
   11:  *----------------------------------------------------------------------
   12:  */
   13: 
   14: /*
   15:  *      fastlock.c
   16:  *
   17:  *      High-speed exclusive control lock 
   18:  */
   19: 
   20: #include <config.h>
   21: #include <tk/tkernel.h>
   22: 
   23: #if USE_FAST_LOCK
   24: /* ------------------------------------------------------------------------ */
   25: /*
   26:  *      Inc  Increment cnt, in result if cnt >  0, returns positive value.
   27:  *              If cnt <= 0, returns 0 or negative value.
   28:  *      Dec  Decrement cnt, in result if cnt >= 0, returns positive value.
   29:  *              If cnt <  0, returns 0 or negative value. 
   30:  *      Increment/Decrement and evaluation of the associated result must
   31:  *      be executed exclusively.
   32:  */
   33: 
   34: Inline INT Inc( FastLock *lock )
   35: {
   36:         UINT   imask;
   37:         INT    c;
   38:         DI(imask);
   39:         c = ++lock->cnt;
   40:         EI(imask);
   41:         return c;
   42: }
   43: Inline INT Dec( FastLock *lock )
   44: {
   45:         UINT   imask;
   46:         INT    c;
   47:         DI(imask);
   48:         c = lock->cnt--;
   49:         EI(imask);
   50:         return c;
   51: }
   52: 
   53: /*
   54:  * Lock 
   55:  */
   56: EXPORT void Lock( FastLock *lock )
   57: {
   58:         if ( Inc(lock) > 0 ) {
   59:                 tk_wai_sem(lock->id, 1, TMO_FEVR);
   60:         }
   61: }
   62: 
   63: /*
   64:  * Lock release
   65:  */
   66: EXPORT void Unlock( FastLock *lock )
   67: {
   68:         if ( Dec(lock) > 0 ) {
   69:                 tk_sig_sem(lock->id, 1);
   70:         }
   71: }
   72: 
   73: /*
   74:  * Create high-speed lock 
   75:  */
   76: EXPORT ER CreateLock( FastLock *lock, CONST UB *name )
   77: {
   78:         T_CSEM csem;
   79:         ER     ercd;
   80: 
   81:         csem.sematr  = TA_TPRI;
   82:         csem.isemcnt = 0;
   83:         csem.maxsem  = 1;
   84:         SetOBJNAME(csem.exinf, "FLOC");
   85: 
   86:         ercd = tk_cre_sem(&csem);
   87:         if ( ercd < E_OK ) {
   88:                 return ercd;
   89:         }
   90: 
   91:         lock->id = ercd;
   92:         lock->cnt = -1;
   93:         lock->name = name;
   94:   
   95:         return E_OK;
   96: }
   97: 
   98: /*
   99:  * Delete high-speed lock
  100:  */
  101: EXPORT void DeleteLock( FastLock *lock )
  102: {
  103:         if ( lock->id > 0 ) {
  104:                 tk_del_sem(lock->id);
  105:         }
  106:         lock->id = 0;
  107: }
  108: 
  109: #endif /* USE_FAST_LOCK */