reactos/ntoskrnl/ps/idle.c

   1 /*
   2  * COPYRIGHT:       See COPYING in the top level directory
   3  * PROJECT:         ReactOS kernel
   4  * FILE:            ntoskrnl/ps/idle.c
   5  * PURPOSE:         Using idle time
   6  *
   7  * PROGRAMMERS:     Alex Ionescu (alex@relsoft.net)
   8  *                  David Welch (welch@cwcom.net)
   9  */
  10
  11 /* INCLUDES *****************************************************************/
  12
  13 #include <ntoskrnl.h>
  14 #define NDEBUG
  15 #include <internal/debug.h>
  16
  17 #if defined (ALLOC_PRAGMA)
  18 #pragma alloc_text(INIT, PsInitIdleThread)
  19 #endif
  20
  21 /* GLOBALS *******************************************************************/
  22
  23 extern PEPROCESS PsIdleProcess;
  24
  25 /* FUNCTIONS *****************************************************************/
  26
  27 /** System idle thread procedure
  28  *
  29  */
  30 VOID STDCALL
  31 PsIdleThreadMain(PVOID Context)
  32 {
  33    KIRQL oldlvl;
  34
  35    PKPRCB Prcb = KeGetCurrentPrcb();
  36
  37    for(;;)
  38      {
  39        if (Prcb->DpcData[0].DpcQueueDepth > 0)
  40          {
  41            KeRaiseIrql(DISPATCH_LEVEL,&oldlvl);
  42            KiDispatchInterrupt();
  43            KeLowerIrql(oldlvl);
  44          }
  45
  46        NtYieldExecution();
  47
  48        Ke386HaltProcessor();
  49      }
  50 }
  51
  52 /*
  53  * HACK-O-RAMA
  54  * Antique vestigial code left alive for the sole purpose of First/Idle Thread
  55  * creation until I can merge my fix for properly creating them.
  56  */
  57 NTSTATUS
  58 NTAPI
  59 PsInitializeIdleOrFirstThread(PEPROCESS Process,
  60                               PETHREAD* ThreadPtr,
  61                               PKSTART_ROUTINE StartRoutine,
  62                               KPROCESSOR_MODE AccessMode,
  63                               BOOLEAN First)
  64 {
  65     PETHREAD Thread;
  66     ULONG_PTR KernelStack;
  67     extern unsigned int init_stack_top;
  68
  69     Thread = ExAllocatePool(NonPagedPool, sizeof(ETHREAD));
  70     RtlZeroMemory(Thread, sizeof(ETHREAD));
  71     Thread->ThreadsProcess = Process;
  72     if (First)
  73     {
  74         KernelStack = init_stack_top;
  75     }
  76     else
  77     {
  78         KernelStack = (ULONG_PTR)MmCreateKernelStack(FALSE) + KERNEL_STACK_SIZE;
  79     }
  80     KeInitializeThread(&Process->Pcb,
  81                        &Thread->Tcb,
  82                        PspSystemThreadStartup,
  83                        StartRoutine,
  84                        NULL,
  85                        NULL,
  86                        NULL,
  87                        (PVOID)KernelStack);
  88     InitializeListHead(&Thread->IrpList);
  89     *ThreadPtr = Thread;
  90     return STATUS_SUCCESS;
  91 }
  92
  93 /*
  94  * HACK-O-RAMA
  95  * Antique vestigial code left alive for the sole purpose of First/Idle Thread
  96  * creation until I can merge my fix for properly creating them.
  97  */
  98 VOID
  99 INIT_FUNCTION
 100 NTAPI
 101 PsInitIdleThread(VOID)
 102 {
 103     PETHREAD IdleThread;
 104     KIRQL oldIrql;
 105
 106     PsInitializeIdleOrFirstThread(PsIdleProcess,
 107                                   &IdleThread,
 108                                   PsIdleThreadMain,
 109                                   KernelMode,
 110                                   FALSE);
 111
 112     oldIrql = KeAcquireDispatcherDatabaseLock ();
 113     KiUnblockThread(&IdleThread->Tcb, NULL, 0);
 114     KeReleaseDispatcherDatabaseLock(oldIrql);
 115
 116     KeGetCurrentPrcb()->IdleThread = &IdleThread->Tcb;
 117     KeSetPriorityThread(&IdleThread->Tcb, LOW_PRIORITY);
 118     KeSetAffinityThread(&IdleThread->Tcb, 1 << 0);
 119 }