- Fix some bugs in Kernel Queue implementation:
[reactos.git] / reactos / ntoskrnl / ke / queue.c
index 8889e3c..53d451a 100644 (file)
 /*
- *  ReactOS kernel
- *  Copyright (C) 1998, 1999, 2000, 2001, 2002 ReactOS Team
- *
- *  This program is free software; you can redistribute it and/or modify
- *  it under the terms of the GNU General Public License as published by
- *  the Free Software Foundation; either version 2 of the License, or
- *  (at your option) any later version.
- *
- *  This program is distributed in the hope that it will be useful,
- *  but WITHOUT ANY WARRANTY; without even the implied warranty of
- *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- *  GNU General Public License for more details.
- *
- *  You should have received a copy of the GNU General Public License
- *  along with this program; if not, write to the Free Software
- *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
- */
-/* $Id: queue.c,v 1.1 2002/01/04 13:08:39 ekohl Exp $
- *
+ * COPYRIGHT:       See COPYING in the top level directory
  * PROJECT:         ReactOS kernel
  * FILE:            ntoskrnl/ke/queue.c
  * PURPOSE:         Implements kernel queues
- * PROGRAMMER:      Eric Kohl (ekohl@rz-online.de)
- * UPDATE HISTORY:
- *                  Created 04/01/2002
+ *
+ * PROGRAMMERS:     Alex Ionescu (alex@relsoft.net)
+ *                  Gunnar Dalsnes
+ *                  Eric Kohl (ekohl@rz-online.de)
  */
 
 /* INCLUDES *****************************************************************/
 
-#include <ddk/ntddk.h>
-#include <internal/ke.h>
-#include <internal/id.h>
-
+#include <ntoskrnl.h>
 #define NDEBUG
 #include <internal/debug.h>
 
 /* FUNCTIONS *****************************************************************/
 
-VOID STDCALL
+LONG STDCALL KiInsertQueue(IN PKQUEUE Queue, IN PLIST_ENTRY Entry, BOOLEAN Head);
+
+/*
+ * @implemented
+ */
+VOID
+STDCALL
 KeInitializeQueue(IN PKQUEUE Queue,
-                 IN ULONG Count OPTIONAL)
+                  IN ULONG Count OPTIONAL)
 {
-  KeInitializeDispatcherHeader(&Queue->Header,
-                              InternalQueueType,
-                              sizeof(KQUEUE)/sizeof(ULONG),
-                              0);
-  InitializeListHead(&Queue->EntryListHead);
-  InitializeListHead(&Queue->ThreadListEntry);
-  Queue->CurrentCount = 0;
-  Queue->MaximumCount = (Count == 0) ? KeNumberProcessors : Count;
-}
+    DPRINT("KeInitializeQueue %x\n", Queue);
 
+    /* Initialize the Header */
+    KeInitializeDispatcherHeader(&Queue->Header,
+                                 QueueObject,
+                                 sizeof(KQUEUE)/sizeof(ULONG),
+                                 0);
 
-LONG STDCALL
-KeReadStateQueue(IN PKQUEUE Queue)
-{
-  return(Queue->Header.SignalState);
-}
+    /* Initialize the Lists */
+    InitializeListHead(&Queue->EntryListHead);
+    InitializeListHead(&Queue->ThreadListHead);
 
+    /* Set the Current and Maximum Count */
+    Queue->CurrentCount = 0;
+    Queue->MaximumCount = (Count == 0) ? (ULONG) KeNumberProcessors : Count;
+}
 
-LONG STDCALL
+/*
+ * @implemented
+ */
+LONG
+STDCALL
 KeInsertHeadQueue(IN PKQUEUE Queue,
-                 IN PLIST_ENTRY Entry)
+                  IN PLIST_ENTRY Entry)
 {
-  UNIMPLEMENTED;
-  return 0;
-}
+    LONG PreviousState;
+    KIRQL OldIrql;
+
+    DPRINT("KeInsertHeadQueue %x\n", Queue);
 
+    /* Lock the Dispatcher Database */
+    OldIrql = KeAcquireDispatcherDatabaseLock();
 
+    /* Insert the Queue */
+    PreviousState = KiInsertQueue(Queue, Entry, TRUE);
+
+    /* Release the Dispatcher Lock */
+    KeReleaseDispatcherDatabaseLock(OldIrql);
+
+    /* Return previous State */
+    return PreviousState;
+}
+
+/*
+ * @implemented
+ */
 LONG STDCALL
 KeInsertQueue(IN PKQUEUE Queue,
-             IN PLIST_ENTRY Entry)
+              IN PLIST_ENTRY Entry)
 {
-  UNIMPLEMENTED;
-  return 0;
+    LONG PreviousState;
+    KIRQL OldIrql;
+
+    DPRINT("KeInsertQueue %x\n", Queue);
+
+    /* Lock the Dispatcher Database */
+    OldIrql = KeAcquireDispatcherDatabaseLock();
+
+    /* Insert the Queue */
+    PreviousState = KiInsertQueue(Queue, Entry, FALSE);
+
+    /* Release the Dispatcher Lock */
+    KeReleaseDispatcherDatabaseLock(OldIrql);
+
+    /* Return previous State */
+    return PreviousState;
 }
 
+/*
+ * @implemented
+ *
+ * Returns number of entries in the queue
+ */
+LONG
+STDCALL
+KeReadStateQueue(IN PKQUEUE Queue)
+{
+    /* Returns the Signal State */
+    return(Queue->Header.SignalState);
+}
 
-PLIST_ENTRY STDCALL
+/*
+ * @implemented
+ */
+PLIST_ENTRY
+STDCALL
 KeRemoveQueue(IN PKQUEUE Queue,
-             IN KPROCESSOR_MODE WaitMode,
-             IN PLARGE_INTEGER Timeout OPTIONAL)
+              IN KPROCESSOR_MODE WaitMode,
+              IN PLARGE_INTEGER Timeout OPTIONAL)
 {
-  UNIMPLEMENTED;
-  return NULL;
-}
+    PLIST_ENTRY QueueEntry;
+    NTSTATUS Status;
+    PKTHREAD Thread = KeGetCurrentThread();
+    KIRQL OldIrql;
+    PKQUEUE PreviousQueue;
+    PKWAIT_BLOCK WaitBlock;
+    PKTIMER Timer;
+    DPRINT("KeRemoveQueue %x\n", Queue);
+
+    /* Check if the Lock is already held */
+    if (Thread->WaitNext)
+    {
+        DPRINT("Lock is already held\n");
+        Thread->WaitNext = FALSE;
+    }
+    else
+    {
+        /* Lock the Dispatcher Database */
+        DPRINT("Lock not held, acquiring\n");
+        OldIrql = KeAcquireDispatcherDatabaseLock();
+        Thread->WaitIrql = OldIrql;
+    }
+
+    /* This is needed so that we can set the new queue right here, before additional processing */
+    PreviousQueue = Thread->Queue;
+    Thread->Queue = Queue;
+
+    /* Check if this is a different queue */
+    if (Queue != PreviousQueue)
+    {
+        DPRINT("Different Queue\n");
+        QueueEntry = &Thread->QueueListEntry;
+        if (PreviousQueue)
+        {
+            /* Remove from this list */
+            DPRINT("Removing Old Queue\n");
+            RemoveEntryList(QueueEntry);
+
+            /* Wake the queue */
+            DPRINT("Activating new thread\n");
+            KiWakeQueue(PreviousQueue);
+        }
+
+        /* Insert in this new Queue */
+        DPRINT("Inserting new Queue!\n");
+        InsertTailList(&Queue->ThreadListHead, QueueEntry);
+    }
+    else
+    {
+        /* Same queue, decrement waiting threads */
+        DPRINT("Same Queue!\n");
+        Queue->CurrentCount--;
+    }
+
+    /* Loop until the queue is processed */
+    while (TRUE)
+    {
+        /* Check if the counts are valid and if there is still a queued entry */
+        QueueEntry = Queue->EntryListHead.Flink;
+        if ((Queue->CurrentCount < Queue->MaximumCount) &&
+            (QueueEntry != &Queue->EntryListHead))
+        {
+            /* Remove the Entry and Save it */
+            DPRINT("Removing Queue Entry. CurrentCount: %d, Maximum Count: %d\n",
+                    Queue->CurrentCount, Queue->MaximumCount);
+
+            /* Decrease the number of entries */
+            Queue->Header.SignalState--;
+
+            /* Increase numbef of running threads */
+            Queue->CurrentCount++;
+
+            /* Check if the entry is valid. If not, bugcheck */
+            if (!(QueueEntry->Flink) || !(QueueEntry->Blink))
+            {
+                KEBUGCHECK(INVALID_WORK_QUEUE_ITEM);
+            }
+
+            /* Remove the Entry */
+            RemoveEntryList(QueueEntry);
+            QueueEntry->Flink = NULL;
+
+            /* Nothing to wait on */
+            break;
+        }
+        else
+        {
+            /* Do the wait */
+            DPRINT("Waiting on Queue Entry. CurrentCount: %d, Maximum Count: %d\n",
+                    Queue->CurrentCount, Queue->MaximumCount);
+
+            /* Use the Thread's Wait Block, it's big enough */
+            Thread->WaitBlockList = &Thread->WaitBlock[0];
+
+            /* Check if a kernel APC is pending and we were below APC_LEVEL */
+            if ((Thread->ApcState.KernelApcPending) &&
+                (Thread->WaitIrql < APC_LEVEL))
+            {
+                /* Increment the count and unlock the dispatcher */
+                Queue->CurrentCount++;
+                KeReleaseDispatcherDatabaseLock(Thread->WaitIrql);
+                goto SkipWait;
+            }
 
+            /* Fail if there's a User APC Pending */
+            if ((WaitMode != KernelMode) && (Thread->ApcState.UserApcPending))
+            {
+                /* Return the status and increase the pending threads */
+                QueueEntry = (PLIST_ENTRY)STATUS_USER_APC;
+                Queue->CurrentCount++;
 
-PLIST_ENTRY STDCALL
+                /* Nothing to wait on */
+                break;
+            }
+
+            /* Build the Wait Block */
+            WaitBlock = &Thread->WaitBlock[0];
+            WaitBlock->Object = (PVOID)Queue;
+            WaitBlock->WaitKey = STATUS_SUCCESS;
+            WaitBlock->WaitType = WaitAny;
+            WaitBlock->Thread = Thread;
+            Thread->WaitStatus = STATUS_WAIT_0;
+
+            /* We need to wait for the object... check if we have a timeout */
+            if (Timeout)
+            {
+                /* If it's zero, then don't do any waiting */
+                if (!Timeout->QuadPart)
+                {
+                    /* Instant Timeout, return the status and increase the pending threads */
+                    DPRINT("Queue Wait has timed out\n");
+                    QueueEntry = (PLIST_ENTRY)STATUS_TIMEOUT;
+                    Queue->CurrentCount++;
+
+                    /* Nothing to wait on */
+                    break;
+                }
+
+                /*
+                 * Set up the Timer. We'll use the internal function so that we can
+                 * hold on to the dispatcher lock.
+                 */
+                Timer = &Thread->Timer;
+                WaitBlock->NextWaitBlock = &Thread->WaitBlock[1];
+                WaitBlock = &Thread->WaitBlock[1];
+
+                /* Set up the Timer Wait Block */
+                WaitBlock->Object = (PVOID)Timer;
+                WaitBlock->Thread = Thread;
+                WaitBlock->WaitKey = STATUS_TIMEOUT;
+                WaitBlock->WaitType = WaitAny;
+
+                /* Link the timer to this Wait Block */
+                InitializeListHead(&Timer->Header.WaitListHead);
+                InsertTailList(&Timer->Header.WaitListHead, &WaitBlock->WaitListEntry);
+
+                /* Create Timer */
+                DPRINT("Creating Timer with timeout %I64d\n", *Timeout);
+                KiInsertTimer(Timer, *Timeout);
+            }
+
+            /* Close the loop */
+            WaitBlock->NextWaitBlock = &Thread->WaitBlock[0];
+
+            /* Insert the wait block into the Queues's wait list */
+            WaitBlock = &Thread->WaitBlock[0];
+            InsertTailList(&Queue->Header.WaitListHead,
+                           &WaitBlock->WaitListEntry);
+
+            /* Block the Thread */
+            DPRINT("Blocking the Thread: %x %x!\n", KeGetCurrentThread(), Thread);
+            KiBlockThread(&Status,
+                          FALSE,
+                          WaitMode,
+                          WrQueue);
+
+            /* Reset the wait reason */
+            Thread->WaitReason = 0;
+
+            /* Check if we were executing an APC */
+            if (Status != STATUS_KERNEL_APC)
+            {
+                /* Done Waiting  */
+                DPRINT("Done waking queue. Thread: %x %x!\n", KeGetCurrentThread(), Thread);
+                return (PLIST_ENTRY)Status;
+            }
+
+            /* Check if we had a timeout */
+            if (Timeout)
+            {
+                /* FIXME: Fixup interval */
+            }
+
+            /* Acquire again the lock */
+SkipWait:
+            DPRINT("Looping again\n");
+            OldIrql = KeAcquireDispatcherDatabaseLock();
+
+            /* Save the new IRQL and decrease number of waiting threads */
+            Thread->WaitIrql = OldIrql;
+            Queue->CurrentCount--;
+        }
+    }
+
+    /* Unlock Database and return */
+    KeReleaseDispatcherDatabaseLock(Thread->WaitIrql);
+    DPRINT("Returning. CurrentCount: %d, Maximum Count: %d\n",
+            Queue->CurrentCount, Queue->MaximumCount);
+    return QueueEntry;
+}
+
+/*
+ * @implemented
+ */
+PLIST_ENTRY
+STDCALL
 KeRundownQueue(IN PKQUEUE Queue)
 {
-  UNIMPLEMENTED;
-  return NULL;
+    PLIST_ENTRY EnumEntry;
+    PLIST_ENTRY FirstEntry = NULL;
+    PKTHREAD Thread;
+    KIRQL OldIrql;
+
+    DPRINT("KeRundownQueue(Queue %x)\n", Queue);
+
+    /* Get the Dispatcher Lock */
+    OldIrql = KeAcquireDispatcherDatabaseLock();
+
+    /* Make sure the list is not empty */
+    if (!IsListEmpty(&Queue->EntryListHead))
+    {
+        /* Remove it */
+        FirstEntry = RemoveHeadList(&Queue->EntryListHead);
+    }
+
+    /* Unlink threads and clear their Thread->Queue */
+    while (!IsListEmpty(&Queue->ThreadListHead))
+    {
+        /* Get the Entry and Remove it */
+        EnumEntry = RemoveHeadList(&Queue->ThreadListHead);
+
+        /* Get the Entry's Thread */
+        Thread = CONTAINING_RECORD(EnumEntry, KTHREAD, QueueListEntry);
+
+        /* Kill its Queue */
+        Thread->Queue = NULL;
+    }
+
+    /* Release the lock and return */
+    KeReleaseDispatcherDatabaseLock(OldIrql);
+    return FirstEntry;
+}
+
+/*
+ * Called when a thread which has a queue entry is entering a wait state
+ */
+VOID
+FASTCALL
+KiWakeQueue(IN PKQUEUE Queue)
+{
+    PLIST_ENTRY QueueEntry;
+    PLIST_ENTRY WaitEntry;
+    PKWAIT_BLOCK WaitBlock;
+    PKTHREAD Thread;
+
+    /* Decrement the number of active threads */
+    DPRINT("KiWakeQueue: %x. Thread: %x\n", Queue, KeGetCurrentThread());
+    Queue->CurrentCount--;
+
+    /* Make sure the counts are OK */
+    if (Queue->CurrentCount < Queue->MaximumCount)
+    {
+        /* Get the Queue Entry */
+        QueueEntry = Queue->EntryListHead.Flink;
+
+        /* Get the Wait Entry */
+        WaitEntry = Queue->Header.WaitListHead.Blink;
+        DPRINT("Queue Count is ok; entries: %p, %p\n", QueueEntry, WaitEntry);
+
+        /* Make sure that the Queue entries are not part of empty lists */
+        if ((WaitEntry != &Queue->Header.WaitListHead) &&
+            (QueueEntry != &Queue->EntryListHead))
+        {
+            /* Remove this entry */
+            DPRINT("Queue in List, removing it\n");
+            RemoveEntryList(QueueEntry);
+            QueueEntry->Flink = NULL;
+
+            /* Decrease the Signal State */
+            Queue->Header.SignalState--;
+
+            /* Unwait the Thread */
+            WaitBlock = CONTAINING_RECORD(WaitEntry,
+                                          KWAIT_BLOCK,
+                                          WaitListEntry);
+            Thread = WaitBlock->Thread;
+            DPRINT1("Unwaiting Thread: %d\n", Thread->State);
+            KiAbortWaitThread(Thread, (NTSTATUS)QueueEntry, IO_NO_INCREMENT);
+        }
+    }
+}
+
+/*
+ * Returns the previous number of entries in the queue
+ */
+LONG
+STDCALL
+KiInsertQueue(IN PKQUEUE Queue,
+              IN PLIST_ENTRY Entry,
+              BOOLEAN Head)
+{
+    ULONG InitialState;
+    PKTHREAD Thread = KeGetCurrentThread();
+    PKWAIT_BLOCK WaitBlock;
+    PLIST_ENTRY WaitEntry;
+    DPRINT("KiInsertQueue(Queue %x, Entry %x)\n", Queue, Entry);
+
+    /* Save the old state */
+    InitialState = Queue->Header.SignalState;
+
+    /* Get the Entry */
+    WaitEntry = Queue->Header.WaitListHead.Blink;
+    DPRINT("Initial State, WaitEntry: %d, %x\n", InitialState, WaitEntry);
+
+    /*
+     * Why the KeGetCurrentThread()->Queue != Queue?
+     * KiInsertQueue might be called from an APC for the current thread.
+     * -Gunnar
+     */
+    if ((Queue->CurrentCount < Queue->MaximumCount) &&
+        (WaitEntry != &Queue->Header.WaitListHead) &&
+        ((Thread->Queue != Queue) || (Thread->WaitReason != WrQueue)))
+    {
+        /* Remove the wait entry */
+        DPRINT("Removing Entry\n");
+        RemoveEntryList(WaitEntry);
+
+        /* Get the Wait Block and Thread */
+        WaitBlock = CONTAINING_RECORD(WaitEntry, KWAIT_BLOCK, WaitListEntry);
+        DPRINT("Got wait block: %x\n", WaitBlock);
+        Thread = WaitBlock->Thread;
+
+        /* Reset the wait reason */
+        Thread->WaitReason = 0;
+
+        /* Increase the active threads and set the status*/
+        Queue->CurrentCount++;
+        Thread->WaitStatus = (NTSTATUS)Entry;
+
+        /* Remove the thread from its wait list */
+        RemoveEntryList(&Thread->WaitListEntry);
+
+        /* Check if there's a Thread Timer */
+        if (Thread->Timer.Header.Inserted)
+        {
+            /* Cancel the Thread Timer with the no-lock fastpath */
+            DPRINT("Removing the Thread's Timer\n");
+            Thread->Timer.Header.Inserted = FALSE;
+            RemoveEntryList(&Thread->Timer.TimerListEntry);
+        }
+
+        /* Reschedule the Thread */
+        DPRINT("Unblocking the Thread\n");
+        KiUnblockThread(Thread, (PNTSTATUS)&Entry, 0);
+    }
+    else
+    {
+        /* Increase the Entries */
+        DPRINT("Adding new Queue Entry: %d %d\n", Head, Queue->Header.SignalState);
+        Queue->Header.SignalState++;
+
+        /* Check which mode we're using */
+        if (Head)
+        {
+            /* Insert in the head */
+            InsertHeadList(&Queue->EntryListHead, Entry);
+        }
+        else
+        {
+            /* Insert at the end */
+            InsertTailList(&Queue->EntryListHead, Entry);
+        }
+    }
+
+    /* Return the previous state */
+    DPRINT("Returning\n");
+    return InitialState;
 }
 
 /* EOF */