arch/.unmaintained/arm-all/exec/switch.c

   1 /*
   2     Copyright © 1995-2001, The AROS Development Team. All rights reserved.
   3     $Id$
   4
   5     Desc: Native version of Switch().
   6     Lang: english
   7 */
   8
   9 #include <exec/execbase.h>
  10 #include <proto/exec.h>
  11
  12 #define DEBUG 0
  13 #include <aros/debug.h>
  14
  15 #include "arm_exec_internal.h"
  16
  17 AROS_LH0(void, Switch,
  18     struct ExecBase *, SysBase, 9, Exec)
  19 {
  20     AROS_LIBFUNC_INIT
  21
  22     struct Task *this = SysBase->ThisTask;
  23
  24     /*
  25         If the state is not TS_RUN then the task is already in a list
  26     */
  27     Disable();
  28
  29     if( (this->tc_State != TS_RUN)
  30          && !(this->tc_Flags & TF_EXCEPT) )
  31     {
  32         /*      Its quite possible that they have interrupts Disabled(),
  33             we should fix that here, otherwise we can't switch.
  34
  35             We can't call the dispatcher because we need a signal,
  36             lets just create one.
  37
  38             Have to set the dispatch-required flag.
  39             I use SIGUSR1 (maps to SoftInt) because it has less effect on
  40             the system clock, and is probably quicker.
  41         */
  42
  43         SysBase->AttnResched |= 0x8000;
  44         __asm__ __volatile__ ("swi #0\n\t");
  45     }
  46
  47     Enable();
  48
  49     AROS_LIBFUNC_EXIT
  50 } /* Switch() */