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((PLONG)&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             KEBUGCHECKEX(WORKER_THREAD_RETURNED_AT_BAD_IRQL,
  82                          (ULONG_PTR)WorkItem->WorkerRoutine,
  83                          KeGetCurrentIrql(),
  84                          (ULONG_PTR)WorkItem->Parameter,
  85                          (ULONG_PTR)WorkItem);
  86         }
  87
  88         /* Make sure it returned with Impersionation Disabled */
  89         if (PsGetCurrentThread()->ActiveImpersonationInfo) {
  90
  91             KEBUGCHECKEX(IMPERSONATING_WORKER_THREAD,
  92                          (ULONG_PTR)WorkItem->WorkerRoutine,
  93                          (ULONG_PTR)WorkItem->Parameter,
  94                          (ULONG_PTR)WorkItem,
  95                          0);
  96         }
  97     }
  98 }
  99
 100 static
 101 VOID
 102 STDCALL
 103 ExpInitializeWorkQueue(WORK_QUEUE_TYPE WorkQueueType,
 104                        KPRIORITY Priority)
 105 {
 106     ULONG i;
 107     PETHREAD Thread;
 108     HANDLE hThread;
 109
 110     /* Loop through how many threads we need to create */
 111     for (i = 0; i < NUMBER_OF_WORKER_THREADS; i++) {
 112
 113         /* Create the System Thread */
 114         PsCreateSystemThread(&hThread,
 115                              THREAD_ALL_ACCESS,
 116                              NULL,
 117                              NULL,
 118                              NULL,
 119                              ExpWorkerThreadEntryPoint,
 120                              (PVOID)WorkQueueType);
 121
 122         /* Get the Thread */
 123         ObReferenceObjectByHandle(hThread,
 124                                   THREAD_SET_INFORMATION,
 125                                   PsThreadType,
 126                                   KernelMode,
 127                                   (PVOID*)&Thread,
 128                                   NULL);
 129
 130         /* Set the Priority */
 131         KeSetPriorityThread(&Thread->Tcb, Priority);
 132
 133         /* Dereference and close handle */
 134         ObDereferenceObject(Thread);
 135         ZwClose(hThread);
 136     }
 137 }
 138
 139 VOID
 140 INIT_FUNCTION
 141 STDCALL
 142 ExpInitializeWorkerThreads(VOID)
 143 {
 144     ULONG WorkQueueType;
 145
 146     /* Initialize the Array */
 147     for (WorkQueueType = 0; WorkQueueType < MaximumWorkQueue; WorkQueueType++) {
 148
 149         RtlZeroMemory(&ExWorkerQueue[WorkQueueType], sizeof(EX_WORK_QUEUE));
 150         KeInitializeQueue(&ExWorkerQueue[WorkQueueType].WorkerQueue, 0);
 151     }
 152
 153     /* Create the built-in worker threads for each work queue */
 154     ExpInitializeWorkQueue(CriticalWorkQueue, LOW_REALTIME_PRIORITY);
 155     ExpInitializeWorkQueue(DelayedWorkQueue, LOW_PRIORITY);
 156     ExpInitializeWorkQueue(HyperCriticalWorkQueue, HIGH_PRIORITY);
 157 }
 158
 159 /*
 160  * @implemented
 161  *
 162  * FUNCTION: Inserts a work item in a queue for one of the system worker
 163  * threads to process
 164  * ARGUMENTS:
 165  *        WorkItem = Item to insert
 166  *        QueueType = Queue to insert it in
 167  */
 168 VOID
 169 STDCALL
 170 ExQueueWorkItem(PWORK_QUEUE_ITEM WorkItem,
 171                 WORK_QUEUE_TYPE QueueType)
 172 {
 173     ASSERT(WorkItem!=NULL);
 174     ASSERT_IRQL(DISPATCH_LEVEL);
 175     ASSERT(WorkItem->List.Flink == NULL);
 176
 177     /* Insert the Queue */
 178     KeInsertQueue(&ExWorkerQueue[QueueType].WorkerQueue, &WorkItem->List);
 179 }
 180
 181 /* EOF */