arch/ppc-chrp/exec/remtask.c

   1 /*
   2     Copyright © 1995-2001, The AROS Development Team. All rights reserved.
   3     $Id$
   4
   5     Desc: Remove a task
   6     Lang: english
   7 */
   8 #include <exec/execbase.h>
   9 #include <exec/tasks.h>
  10 #include <aros/libcall.h>
  11 #include <proto/exec.h>
  12 #include <proto/kernel.h>
  13
  14 extern void *priv_KernelBase;
  15
  16 #include "etask.h"
  17 #include "exec_util.h"
  18
  19 #include "exec_debug.h"
  20 #ifndef DEBUG_RemTask
  21 #   define DEBUG_RemTask 0
  22 #endif
  23 #undef DEBUG
  24 #if DEBUG_RemTask
  25 #   define DEBUG 1
  26 #endif
  27 #include <aros/debug.h>
  28
  29 /*****************************************************************************
  30
  31     NAME */
  32
  33         AROS_LH1(void, RemTask,
  34
  35 /*  SYNOPSIS */
  36         AROS_LHA(struct Task *,     task, A1),
  37
  38 /*  LOCATION */
  39         struct ExecBase *, SysBase, 48, Exec)
  40
  41 /*  FUNCTION
  42         Remove a task from the task lists. All memory in the tc_MemEntry list
  43         is freed and a rescedule is done. It's safe to call RemTask() out
  44         of Forbid() or Disable().
  45         This function is one way to get rid of the current task. The other way
  46         is to fall through the end of the entry point.
  47
  48     INPUTS
  49         task - Task to be removed. NULL means current task.
  50
  51     RESULT
  52
  53     NOTES
  54
  55     EXAMPLE
  56
  57     BUGS
  58
  59     SEE ALSO
  60         AddTask()
  61
  62     INTERNALS
  63
  64     HISTORY
  65
  66 ******************************************************************************/
  67 {
  68     AROS_LIBFUNC_INIT
  69     struct MemList *mb;
  70     void *KernelBase = priv_KernelBase;
  71     struct ETask *et;
  72
  73     /* A value of NULL means current task */
  74     if (task==NULL)
  75         task=SysBase->ThisTask;
  76
  77     D(bug("[exec] Call RemTask (%012lx (\"%s\"))\n", task, task->tc_Node.ln_Name));
  78
  79     /*
  80         Since it's possible that the following will free a task
  81         structure that is used for some time afterwards it's
  82         necessary to protect the free memory list so that nobody
  83         can allocate that memory.
  84     */
  85     Forbid();
  86
  87     /* Remove() here, before freeing the MemEntry list. Because
  88        the MemEntry list might contain the task struct itself! */
  89
  90     if(task != SysBase->ThisTask)
  91     {
  92         Remove(&task->tc_Node);
  93     }
  94
  95     KrnDeleteContext(GetIntETask(task)->iet_Context);
  96
  97     et = GetETask(task);
  98     if (et != NULL)
  99     {
 100         CleanupETask(task, et);
 101     }
 102
 103     /* Free all memory in the tc_MemEntry list. */
 104     while((mb=(struct MemList *)RemHead(&task->tc_MemEntry))!=NULL)
 105         /* Free one MemList node */
 106         FreeEntry(mb);
 107
 108     /* Changing the task lists always needs a Disable(). */
 109     Disable();
 110
 111     /* Freeing myself? */
 112     if(task==SysBase->ThisTask)
 113     {
 114         /* Can't do that - let the dispatcher do it. */
 115         task->tc_State=TS_REMOVED;
 116
 117         /*
 118             Since I don't know how many levels of Forbid()
 119             are already pending I set a default value.
 120         */
 121         SysBase->TDNestCnt=-1;
 122
 123 //        task->tc_Node.ln_Pred->ln_Succ = task->tc_Node.ln_Succ;
 124 //      task->tc_Node.ln_Succ->ln_Pred = task->tc_Node.ln_Pred;
 125
 126         /* And force a task switch. Note: Dispatch, not Switch,
 127            because the state of thistask must not be saved ->
 128            after all the mem for the task + intetask + context
 129            could already have been freed by the FreeEntry() call
 130            above!!! */
 131
 132         KrnDispatch();
 133         /* Does not return. */
 134     }
 135
 136     /* All done. */
 137     Enable();
 138     Permit();
 139
 140     ReturnVoid ("RemTask");
 141     AROS_LIBFUNC_EXIT
 142 }
 143
 144