rom/exec/findtaskbypid.c

   1 /*
   2     Copyright © 1995-2017, The AROS Development Team. All rights reserved.
   3     $Id$
   4 */
   5
   6 #define DEBUG 0
   7
   8 #include <exec/execbase.h>
   9 #include <exec/tasks.h>
  10
  11 #include "exec_intern.h"
  12 #include "exec_locks.h"
  13
  14 /*****************************************************************************
  15
  16     NAME */
  17 #include <proto/exec.h>
  18
  19         AROS_LH1(struct Task *, FindTaskByPID,
  20
  21 /*  SYNOPSIS */
  22         AROS_LHA(ULONG, id, D0),
  23
  24 /*  LOCATION */
  25         struct ExecBase *, SysBase, 166, Exec)
  26
  27 /*  FUNCTION
  28         Scan through the task lists searching for the task whose
  29         et_UniqueID field matches.
  30
  31     INPUTS
  32         id      -   The task ID to match.
  33
  34     RESULT
  35         Address of the Task control structure that matches, or
  36         NULL otherwise.
  37
  38     NOTES
  39         This function is source-compatible with MorphOS.
  40
  41     EXAMPLE
  42
  43     BUGS
  44
  45     SEE ALSO
  46
  47     INTERNALS
  48
  49 ******************************************************************************/
  50 {
  51     AROS_LIBFUNC_INIT
  52
  53 #if !defined(__AROSEXEC_SMP__)
  54     struct Task *thisTask = GET_THIS_TASK;
  55 #endif
  56     struct Task *t;
  57     struct ETask *et;
  58
  59     D(bug("[EXEC] %s()\n", __func__);)
  60
  61     /* First up, check running task(s) */
  62 #if defined(__AROSEXEC_SMP__)
  63     EXEC_LOCK_READ_AND_DISABLE(&PrivExecBase(SysBase)->TaskRunningSpinLock);
  64     ForeachNode(&PrivExecBase(SysBase)->TaskRunning, t)
  65     {
  66         D(bug("[EXEC] %s: trying Running Task @ 0x%p\n", __func__, t);)
  67         et = GetETask(t);
  68         if (et != NULL && et->et_UniqueID == id)
  69         {
  70             EXEC_UNLOCK_AND_ENABLE(&PrivExecBase(SysBase)->TaskRunningSpinLock);
  71             return t;
  72         }
  73     }
  74     EXEC_UNLOCK_AND_ENABLE(&PrivExecBase(SysBase)->TaskRunningSpinLock);
  75
  76     EXEC_LOCK_READ_AND_DISABLE(&PrivExecBase(SysBase)->TaskSpinningLock);
  77     ForeachNode(&PrivExecBase(SysBase)->TaskSpinning, t)
  78     {
  79         D(bug("[EXEC] %s: trying Spinning Task @ 0x%p\n", __func__, t);)
  80         et = GetETask(t);
  81         if (et != NULL && et->et_UniqueID == id)
  82         {
  83             EXEC_UNLOCK_AND_ENABLE(&PrivExecBase(SysBase)->TaskSpinningLock);
  84             return t;
  85         }
  86     }
  87     EXEC_UNLOCK_AND_ENABLE(&PrivExecBase(SysBase)->TaskSpinningLock);
  88
  89     EXEC_LOCK_READ_AND_DISABLE(&PrivExecBase(SysBase)->TaskReadySpinLock);
  90 #else
  91     Disable();
  92     if ((t = thisTask) != NULL)
  93     {
  94         D(bug("[EXEC] %s: trying ThisTask @ 0x%p\n", __func__, t);)
  95         et = GetETask(t);
  96         if (et != NULL && et->et_UniqueID == id)
  97         {
  98             Enable();
  99             return t;
 100         }
 101     }
 102 #endif
 103     /*  Next, go through the ready list */
 104     ForeachNode(&SysBase->TaskReady, t)
 105     {
 106         D(bug("[EXEC] %s: trying Ready Task @ 0x%p\n", __func__, t);)
 107         et = GetETask(t);
 108         if (et != NULL && et->et_UniqueID == id)
 109         {
 110 #if defined(__AROSEXEC_SMP__)
 111             EXEC_UNLOCK_AND_ENABLE(&PrivExecBase(SysBase)->TaskReadySpinLock);
 112 #else
 113             Enable();
 114 #endif
 115             return t;
 116         }
 117     }
 118 #if defined(__AROSEXEC_SMP__)
 119     EXEC_UNLOCK_AND_ENABLE(&PrivExecBase(SysBase)->TaskReadySpinLock);
 120
 121     EXEC_LOCK_READ_AND_DISABLE(&PrivExecBase(SysBase)->TaskWaitSpinLock);
 122 #endif
 123     /* Finally, go through the wait list */
 124     ForeachNode(&SysBase->TaskWait, t)
 125     {
 126         D(bug("[EXEC] %s: trying Waiting Task @ 0x%p\n", __func__, t);)
 127
 128         et = GetETask(t);
 129         if (et != NULL && et->et_UniqueID == id)
 130         {
 131 #if defined(__AROSEXEC_SMP__)
 132             EXEC_UNLOCK_AND_ENABLE(&PrivExecBase(SysBase)->TaskWaitSpinLock);
 133 #else
 134             Enable();
 135 #endif
 136             return t;
 137         }
 138     }
 139
 140 #if defined(__AROSEXEC_SMP__)
 141     EXEC_UNLOCK_AND_ENABLE(&PrivExecBase(SysBase)->TaskWaitSpinLock);
 142 #else
 143     Enable();
 144 #endif
 145
 146     D(bug("[EXEC] %s: Not Found\n", __func__);)
 147
 148     return NULL;
 149
 150     AROS_LIBFUNC_EXIT
 151 }