reactos/ntoskrnl/ex/work.c

   1 /*
   2  * COPYRIGHT:          See COPYING in the top level directory
   3  * PROJECT:            ReactOS kernel
   4  * FILE:               ntoskrnl/ex/work.c
   5  * PURPOSE:            Manage system work queues
   6  *
   7  * PROGRAMMERS:        Alex Ionescu - Used correct work queue array and added some fixes and checks.
   8  *                     Gunnar Dalsnes - Implemented
   9  */
  10
  11 /* INCLUDES ******************************************************************/
  12
  13 #include <ntoskrnl.h>
  14 #define NDEBUG
  15 #include <internal/debug.h>
  16
  17 /* DEFINES *******************************************************************/
  18
  19 #define NUMBER_OF_WORKER_THREADS   (5)
  20
  21 /* TYPES *********************************************************************/
  22
  23 /* GLOBALS *******************************************************************/
  24
  25 /*
  26  * PURPOSE: Queue of items waiting to be processed at normal priority
  27  */
  28 EX_WORK_QUEUE ExWorkerQueue[MaximumWorkQueue];
  29
  30 /* FUNCTIONS ****************************************************************/
  31
  32 /*
  33  * FUNCTION: Entry point for a worker thread
  34  * ARGUMENTS:
  35  *         context = Parameters
  36  * RETURNS: Status
  37  * NOTE: To kill a worker thread you must queue an item whose callback
  38  * calls PsTerminateSystemThread
  39  */
  40 static
  41 VOID
  42 STDCALL
  43 ExpWorkerThreadEntryPoint(IN PVOID Context)
  44 {
  45     PWORK_QUEUE_ITEM WorkItem;
  46     PLIST_ENTRY QueueEntry;
  47     WORK_QUEUE_TYPE WorkQueueType;
  48     PEX_WORK_QUEUE WorkQueue;
  49
  50     /* Get Queue Type and Worker Queue */
  51     WorkQueueType = (WORK_QUEUE_TYPE)Context;
  52     WorkQueue = &ExWorkerQueue[WorkQueueType];
  53
  54     /* Loop forever */
  55     while (TRUE) {
  56
  57         /* Wait for Something to Happen on the Queue */
  58         QueueEntry = KeRemoveQueue(&WorkQueue->WorkerQueue, KernelMode, NULL);
  59
  60         /* Can't happen since we do a KernelMode wait (and we're a system thread) */
  61         ASSERT((NTSTATUS)QueueEntry != STATUS_USER_APC);
  62
  63         /* this should never happen either, since we wait with NULL timeout,
  64          * but there's a slight possibility that STATUS_TIMEOUT is returned
  65          * at queue rundown in NT (unlikely) -Gunnar
  66          */
  67         ASSERT((NTSTATUS)QueueEntry != STATUS_TIMEOUT);
  68
  69         /* Increment Processed Work Items */
  70         InterlockedIncrement(&WorkQueue->WorkItemsProcessed);
  71
  72         /* Get the Work Item */
  73         WorkItem = CONTAINING_RECORD(QueueEntry, WORK_QUEUE_ITEM, List);
  74
  75         /* Call the Worker Routine */
  76         WorkItem->WorkerRoutine(WorkItem->Parameter);
  77
  78         /* Make sure it returned at right IRQL */
  79         if (KeGetCurrentIrql() != PASSIVE_LEVEL) {
  80
  81             /* FIXME: Make this an Ex */
  82             KEBUGCHECK(WORKER_THREAD_RETURNED_AT_BAD_IRQL);
  83         }
  84
  85         /* Make sure it returned with Impersionation Disabled */
  86         if (PsGetCurrentThread()->ActiveImpersonationInfo) {
  87
  88             /* FIXME: Make this an Ex */
  89             KEBUGCHECK(IMPERSONATING_WORKER_THREAD);
  90         }
  91     }
  92 }
  93
  94 static
  95 VOID
  96 STDCALL
  97 ExpInitializeWorkQueue(WORK_QUEUE_TYPE WorkQueueType,
  98                        KPRIORITY Priority)
  99 {
 100     ULONG i;
 101     PETHREAD Thread;
 102     HANDLE hThread;
 103
 104     /* Loop through how many threads we need to create */
 105     for (i = 0; i < NUMBER_OF_WORKER_THREADS; i++) {
 106
 107         /* Create the System Thread */
 108         PsCreateSystemThread(&hThread,
 109                              THREAD_ALL_ACCESS,
 110                              NULL,
 111                              NULL,
 112                              NULL,
 113                              ExpWorkerThreadEntryPoint,
 114                              (PVOID)WorkQueueType);
 115
 116         /* Get the Thread */
 117         ObReferenceObjectByHandle(hThread,
 118                                   THREAD_SET_INFORMATION,
 119                                   PsThreadType,
 120                                   KernelMode,
 121                                   (PVOID*)&Thread,
 122                                   NULL);
 123
 124         /* Set the Priority */
 125         KeSetPriorityThread(&Thread->Tcb, Priority);
 126
 127         /* Dereference and close handle */
 128         ObDereferenceObject(Thread);
 129         ZwClose(hThread);
 130     }
 131 }
 132
 133 VOID
 134 INIT_FUNCTION
 135 ExpInitializeWorkerThreads(VOID)
 136 {
 137     ULONG WorkQueueType;
 138
 139     /* Initialize the Array */
 140     for (WorkQueueType = 0; WorkQueueType < MaximumWorkQueue; WorkQueueType++) {
 141
 142         RtlZeroMemory(&ExWorkerQueue[WorkQueueType], sizeof(EX_WORK_QUEUE));
 143         KeInitializeQueue(&ExWorkerQueue[WorkQueueType].WorkerQueue, 0);
 144     }
 145
 146     /* Create the built-in worker threads for each work queue */
 147     ExpInitializeWorkQueue(CriticalWorkQueue, LOW_REALTIME_PRIORITY);
 148     ExpInitializeWorkQueue(DelayedWorkQueue, LOW_PRIORITY);
 149     ExpInitializeWorkQueue(HyperCriticalWorkQueue, HIGH_PRIORITY);
 150 }
 151
 152 /*
 153  * @implemented
 154  *
 155  * FUNCTION: Inserts a work item in a queue for one of the system worker
 156  * threads to process
 157  * ARGUMENTS:
 158  *        WorkItem = Item to insert
 159  *        QueueType = Queue to insert it in
 160  */
 161 VOID
 162 STDCALL
 163 ExQueueWorkItem(PWORK_QUEUE_ITEM WorkItem,
 164                 WORK_QUEUE_TYPE QueueType)
 165 {
 166     ASSERT(WorkItem!=NULL);
 167     ASSERT_IRQL(DISPATCH_LEVEL);
 168     ASSERT(WorkItem->List.Flink == NULL);
 169
 170     /* Insert the Queue */
 171     KeInsertQueue(&ExWorkerQueue[QueueType].WorkerQueue, &WorkItem->List);
 172 }
 173
 174 /* EOF */