22 Jan
2007
22 Jan
'07
6:47 a.m.
Author: ion
Date: Mon Jan 22 09:47:44 2007
New Revision: 25584
URL: http://svn.reactos.org/svn/reactos?rev=25584&view=rev
Log:
- Implement a cute little hack called DEFINE_WAIT_BLOCK which makes pushlocks work on GCC
3.4.5 as well as 4.1.2+ (with no perf-hit on the latter).
- Implement ExWaitForUnblockPushLock (just a wrapper around
ExTimedWaitForUnblockPushLock).
- Simplfy ExBlockPushLock and fix some bugs.
- Fix a bug in ExfReleasePushLockExclusive when we have to wake the lock.
- Fix a bug in ExfUnblockPushLock which was touching the wrong pointer.
- Fix ExWaitOnPushLock to verify that the pushlock is actually locked.
Modified:
trunk/reactos/ntoskrnl/ex/init.c
trunk/reactos/ntoskrnl/ex/pushlock.c
trunk/reactos/ntoskrnl/include/internal/ex.h
Modified: trunk/reactos/ntoskrnl/ex/init.c
URL:
http://svn.reactos.org/svn/reactos/trunk/reactos/ntoskrnl/ex/init.c?rev=255…
==============================================================================
--- trunk/reactos/ntoskrnl/ex/init.c (original)
+++ trunk/reactos/ntoskrnl/ex/init.c Mon Jan 22 09:47:44 2007
@@ -1,11 +1,11 @@
/*
-* PROJECT: ReactOS Kernel
-* LICENSE: GPL - See COPYING in the top level directory
-* FILE: ntoskrnl/ex/init.c
-* PURPOSE: Executive Initialization Code
-* PROGRAMMERS: Alex Ionescu (alex.ionescu(a)reactos.org)
-* Eric Kohl (ekohl(a)rz-online.de)
-*/
+ * PROJECT: ReactOS Kernel
+ * LICENSE: GPL - See COPYING in the top level directory
+ * FILE: ntoskrnl/ex/init.c
+ * PURPOSE: Executive Initialization Code
+ * PROGRAMMERS: Alex Ionescu (alex.ionescu(a)reactos.org)
+ * Eric Kohl (ekohl(a)rz-online.de)
+ */
/* INCLUDES ******************************************************************/
Modified: trunk/reactos/ntoskrnl/ex/pushlock.c
URL:
http://svn.reactos.org/svn/reactos/trunk/reactos/ntoskrnl/ex/pushlock.c?rev…
==============================================================================
--- trunk/reactos/ntoskrnl/ex/pushlock.c (original)
+++ trunk/reactos/ntoskrnl/ex/pushlock.c Mon Jan 22 09:47:44 2007
@@ -342,6 +342,33 @@
}
/*++
+ * @name ExWaitForUnblockPushLock
+ *
+ * The ExWaitForUnblockPushLock routine waits for a pushlock
+ * to be unblocked, for a specified internal.
+ *
+ * @param PushLock
+ * Pointer to a pushlock whose waiter list needs to be optimized.
+ *
+ * @param WaitBlock
+ * Pointer to the pushlock's wait block.
+ *
+ * @return STATUS_SUCCESS is the pushlock is now unblocked, otherwise the error
+ * code returned by KeWaitForSingleObject.
+ *
+ * @remarks If the wait fails, then a manual unblock is attempted.
+ *
+ *--*/
+VOID
+FASTCALL
+ExWaitForUnblockPushLock(IN PEX_PUSH_LOCK PushLock,
+ IN PEX_PUSH_LOCK_WAIT_BLOCK WaitBlock)
+{
+ /* Call the timed function with no timeout */
+ ExTimedWaitForUnblockPushLock(PushLock, WaitBlock, NULL);
+}
+
+/*++
* @name ExBlockPushLock
*
* The ExBlockPushLock routine blocks a pushlock.
@@ -360,25 +387,33 @@
VOID
FASTCALL
ExBlockPushLock(PEX_PUSH_LOCK PushLock,
- PVOID WaitBlock)
-{
- PVOID NewValue, OldValue;
+ PVOID pWaitBlock)
+{
+ PEX_PUSH_LOCK_WAIT_BLOCK WaitBlock = pWaitBlock;
+ EX_PUSH_LOCK NewValue, OldValue;
+
+ /* Detect invalid wait block alignment */
+ ASSERT((ULONG_PTR)pWaitBlock & 0x10);
/* Set the waiting bit */
- ((PEX_PUSH_LOCK_WAIT_BLOCK)WaitBlock)->Flags |= EX_PUSH_LOCK_FLAGS_WAIT;
-
- /* Link the wait blocks */
- ((PEX_PUSH_LOCK_WAIT_BLOCK)WaitBlock)->Next = PushLock->Ptr;
-
- /* Try to set this one as the wait block now */
- NewValue = PushLock->Ptr;
+ WaitBlock->Flags = EX_PUSH_LOCK_FLAGS_WAIT;
+
+ /* Get the old value */
+ OldValue = *PushLock;
+
+ /* Start block loop */
for (;;)
{
+ /* Link the wait blocks */
+ WaitBlock->Next = OldValue.Ptr;
+
/* Set the new wait block value */
- OldValue = InterlockedCompareExchangePointer(&PushLock->Ptr,
- WaitBlock,
- NewValue);
- if (OldValue == NewValue) break;
+ NewValue.Ptr = InterlockedCompareExchangePointer(&PushLock->Ptr,
+ WaitBlock,
+ OldValue.Ptr);
+ if (OldValue.Ptr == NewValue.Ptr) break;
+
+ /* Try again with the new value */
NewValue = OldValue;
}
}
@@ -404,7 +439,7 @@
FASTCALL
ExfAcquirePushLockExclusive(PEX_PUSH_LOCK PushLock)
{
- EX_PUSH_LOCK_WAIT_BLOCK WaitBlock;
+ DEFINE_WAIT_BLOCK(WaitBlock);
EX_PUSH_LOCK OldValue = *PushLock, NewValue, TempValue;
BOOLEAN NeedWake;
ULONG i;
@@ -435,23 +470,23 @@
else
{
/* We'll have to create a Waitblock */
- WaitBlock.Flags = EX_PUSH_LOCK_FLAGS_EXCLUSIVE |
- EX_PUSH_LOCK_FLAGS_WAIT;
- WaitBlock.Previous = NULL;
+ WaitBlock->Flags = EX_PUSH_LOCK_FLAGS_EXCLUSIVE |
+ EX_PUSH_LOCK_FLAGS_WAIT;
+ WaitBlock->Previous = NULL;
NeedWake = FALSE;
/* Check if there is already a waiter */
if (OldValue.Waiting)
{
/* Nobody is the last waiter yet */
- WaitBlock.Last = NULL;
+ WaitBlock->Last = NULL;
/* We are an exclusive waiter */
- WaitBlock.ShareCount = 0;
+ WaitBlock->ShareCount = 0;
/* Set the current Wait Block pointer */
- WaitBlock.Next = (PEX_PUSH_LOCK_WAIT_BLOCK)((ULONG_PTR)
- OldValue.Ptr &~ EX_PUSH_LOCK_PTR_BITS);
+ WaitBlock->Next = (PEX_PUSH_LOCK_WAIT_BLOCK)((ULONG_PTR)
+ OldValue.Ptr &~ EX_PUSH_LOCK_PTR_BITS);
/* Point to ours */
NewValue.Value = (OldValue.Value & EX_PUSH_LOCK_MULTIPLE_SHARED) |
@@ -466,10 +501,10 @@
else
{
/* We are the first waiter, so loop the wait block */
- WaitBlock.Last = &WaitBlock;
+ WaitBlock->Last = WaitBlock;
/* Set the share count */
- WaitBlock.ShareCount = OldValue.Shared;
+ WaitBlock->ShareCount = OldValue.Shared;
/* Check if someone is sharing this pushlock */
if (OldValue.Shared > 1)
@@ -483,7 +518,7 @@
else
{
/* No shared count */
- WaitBlock.ShareCount = 0;
+ WaitBlock->ShareCount = 0;
/* Point to our wait block */
NewValue.Value = EX_PUSH_LOCK_LOCK |
@@ -494,10 +529,10 @@
#if DBG
/* Setup the Debug Wait Block */
- WaitBlock.Signaled = 0;
- WaitBlock.OldValue = OldValue;
- WaitBlock.NewValue = NewValue;
- WaitBlock.PushLock = PushLock;
+ WaitBlock->Signaled = 0;
+ WaitBlock->OldValue = OldValue;
+ WaitBlock->NewValue = NewValue;
+ WaitBlock->PushLock = PushLock;
#endif
/* Sanity check */
@@ -524,26 +559,26 @@
}
/* Set up the Wait Gate */
- KeInitializeGate(&WaitBlock.WakeGate);
+ KeInitializeGate(&WaitBlock->WakeGate);
/* Now spin on the push lock if necessary */
i = ExPushLockSpinCount;
- if ((i) && (WaitBlock.Flags & EX_PUSH_LOCK_WAITING))
+ if ((i) && (WaitBlock->Flags & EX_PUSH_LOCK_WAITING))
{
/* Spin */
while (--i) YieldProcessor();
}
/* Now try to remove the wait bit */
- if (InterlockedBitTestAndReset(&WaitBlock.Flags, 1))
+ if (InterlockedBitTestAndReset(&WaitBlock->Flags, 1))
{
/* Nobody removed it already, let's do a full wait */
- KeWaitForGate(&WaitBlock.WakeGate, WrPushLock, KernelMode);
- ASSERT(WaitBlock.Signaled);
+ KeWaitForGate(&WaitBlock->WakeGate, WrPushLock, KernelMode);
+ ASSERT(WaitBlock->Signaled);
}
/* We shouldn't be shared anymore */
- ASSERT((WaitBlock.ShareCount == 0));
+ ASSERT((WaitBlock->ShareCount == 0));
/* Loop again */
OldValue = NewValue;
@@ -570,7 +605,7 @@
FASTCALL
ExfAcquirePushLockShared(PEX_PUSH_LOCK PushLock)
{
- EX_PUSH_LOCK_WAIT_BLOCK WaitBlock;
+ DEFINE_WAIT_BLOCK(WaitBlock);
EX_PUSH_LOCK OldValue = *PushLock, NewValue;
BOOLEAN NeedWake;
ULONG i;
@@ -614,20 +649,20 @@
else
{
/* We'll have to create a Waitblock */
- WaitBlock.Flags = EX_PUSH_LOCK_FLAGS_WAIT;
- WaitBlock.ShareCount = 0;
+ WaitBlock->Flags = EX_PUSH_LOCK_FLAGS_WAIT;
+ WaitBlock->ShareCount = 0;
NeedWake = FALSE;
- WaitBlock.Previous = NULL;
+ WaitBlock->Previous = NULL;
/* Check if there is already a waiter */
if (OldValue.Waiting)
{
/* Set the current Wait Block pointer */
- WaitBlock.Next = (PEX_PUSH_LOCK_WAIT_BLOCK)((ULONG_PTR)
- OldValue.Ptr &~ EX_PUSH_LOCK_PTR_BITS);
+ WaitBlock->Next = (PEX_PUSH_LOCK_WAIT_BLOCK)((ULONG_PTR)
+ OldValue.Ptr &~ EX_PUSH_LOCK_PTR_BITS);
/* Nobody is the last waiter yet */
- WaitBlock.Last = NULL;
+ WaitBlock->Last = NULL;
/* Point to ours */
NewValue.Value = (OldValue.Value & (EX_PUSH_LOCK_MULTIPLE_SHARED |
@@ -642,7 +677,7 @@
else
{
/* We are the first waiter, so loop the wait block */
- WaitBlock.Last = &WaitBlock;
+ WaitBlock->Last = WaitBlock;
/* Point to our wait block */
NewValue.Value = (OldValue.Value & (EX_PUSH_LOCK_MULTIPLE_SHARED |
@@ -656,10 +691,10 @@
#if DBG
/* Setup the Debug Wait Block */
- WaitBlock.Signaled = 0;
- WaitBlock.OldValue = OldValue;
- WaitBlock.NewValue = NewValue;
- WaitBlock.PushLock = PushLock;
+ WaitBlock->Signaled = 0;
+ WaitBlock->OldValue = OldValue;
+ WaitBlock->NewValue = NewValue;
+ WaitBlock->PushLock = PushLock;
#endif
/* Write the new value */
@@ -683,26 +718,26 @@
}
/* Set up the Wait Gate */
- KeInitializeGate(&WaitBlock.WakeGate);
+ KeInitializeGate(&WaitBlock->WakeGate);
/* Now spin on the push lock if necessary */
i = ExPushLockSpinCount;
- if ((i) && (WaitBlock.Flags & EX_PUSH_LOCK_WAITING))
+ if ((i) && (WaitBlock->Flags & EX_PUSH_LOCK_WAITING))
{
/* Spin */
while (--i) YieldProcessor();
}
/* Now try to remove the wait bit */
- if (InterlockedBitTestAndReset(&WaitBlock.Flags, 1))
+ if (InterlockedBitTestAndReset(&WaitBlock->Flags, 1))
{
/* Fast-path did not work, we need to do a full wait */
- KeWaitForGate(&WaitBlock.WakeGate, WrPushLock, KernelMode);
- ASSERT(WaitBlock.Signaled);
+ KeWaitForGate(&WaitBlock->WakeGate, WrPushLock, KernelMode);
+ ASSERT(WaitBlock->Signaled);
}
/* We shouldn't be shared anymore */
- ASSERT((WaitBlock.ShareCount == 0));
+ ASSERT((WaitBlock->ShareCount == 0));
}
}
}
@@ -1004,7 +1039,7 @@
FASTCALL
ExfReleasePushLockExclusive(PEX_PUSH_LOCK PushLock)
{
- EX_PUSH_LOCK NewValue;
+ EX_PUSH_LOCK NewValue, WakeValue;
EX_PUSH_LOCK OldValue = *PushLock;
/* Loop until we can change */
@@ -1023,6 +1058,28 @@
/* Sanity check */
ASSERT(NewValue.Waking && !NewValue.Locked);
+
+ /* Write the New Value. Save our original value for waking */
+ WakeValue = NewValue;
+ NewValue.Ptr = InterlockedCompareExchangePointer(PushLock,
+ NewValue.Ptr,
+ OldValue.Ptr);
+
+ /* Check if the value changed behind our back */
+ if (NewValue.Value != OldValue.Value)
+ {
+ /* Wake the Pushlock */
+ ExfWakePushLock(PushLock, WakeValue);
+ break;
+ }
+ }
+ else
+ {
+ /* A simple unlock */
+ NewValue.Value = OldValue.Value &~ EX_PUSH_LOCK_LOCK;
+
+ /* Sanity check */
+ ASSERT(NewValue.Waking && !NewValue.Waiting);
/* Write the New Value */
NewValue.Ptr = InterlockedCompareExchangePointer(PushLock,
@@ -1030,36 +1087,11 @@
OldValue.Ptr);
/* Check if the value changed behind our back */
- if (NewValue.Value != OldValue.Value)
- {
- /* Loop again */
- OldValue = NewValue;
- continue;
- }
-
- /* Wake the Pushlock */
- ExfWakePushLock(PushLock, NewValue);
- break;
- }
- else
- {
- /* A simple unlock */
- NewValue.Value = OldValue.Value &~ EX_PUSH_LOCK_LOCK;
-
- /* Sanity check */
- ASSERT(NewValue.Waking && !NewValue.Waiting);
-
- /* Write the New Value */
- NewValue.Ptr = InterlockedCompareExchangePointer(PushLock,
- NewValue.Ptr,
- OldValue.Ptr);
-
- /* Check if the value changed behind our back */
if (NewValue.Value == OldValue.Value) break;
-
- /* Loop again */
- OldValue = NewValue;
- }
+ }
+
+ /* Loop again */
+ OldValue = NewValue;
}
}
@@ -1128,7 +1160,7 @@
KIRQL OldIrql = DISPATCH_LEVEL;
/* Get the wait block and erase the previous one */
- WaitBlock = InterlockedExchangePointer(PushLock->Ptr, 0);
+ WaitBlock = InterlockedExchangePointer(&PushLock->Ptr, NULL);
if (WaitBlock)
{
/* Check if there is a linked pushlock and raise IRQL appropriately */
@@ -1144,7 +1176,7 @@
if (InterlockedBitTestAndReset(&WaitBlock->Flags, 1))
{
/* Nobody removed the flag before us, so signal the event */
- KeSetEventBoostPriority(&WaitBlock->WakeEvent, IO_NO_INCREMENT);
+ KeSetEventBoostPriority(&WaitBlock->WakeEvent, NULL);
}
/* Check if there was a next block */
@@ -1161,6 +1193,6 @@
EX_PUSH_LOCK_FLAGS_WAIT))
{
/* Wait for the pushlock to be unblocked */
- ExTimedWaitForUnblockPushLock(PushLock, CurrentWaitBlock, NULL);
- }
-}
+ ExWaitForUnblockPushLock(PushLock, CurrentWaitBlock);
+ }
+}
Modified: trunk/reactos/ntoskrnl/include/internal/ex.h
URL:
http://svn.reactos.org/svn/reactos/trunk/reactos/ntoskrnl/include/internal/…
==============================================================================
--- trunk/reactos/ntoskrnl/include/internal/ex.h (original)
+++ trunk/reactos/ntoskrnl/include/internal/ex.h Mon Jan 22 09:47:44 2007
@@ -68,6 +68,36 @@
#define ExRundownCompleted _ExRundownCompleted
#define ExGetPreviousMode KeGetPreviousMode
+//
+// Detect GCC 4.1.2+
+//
+#if (__GNUC__ * 10000 + __GNUC_MINOR__ * 100 + __GNUC_PATCHLEVEL__) < 40102
+
+//
+// Broken GCC with Alignment Bug. We'll do alignment ourselves at higher cost.
+//
+#define DEFINE_WAIT_BLOCK(x) \
+ struct _AlignHack \
+ { \
+ UCHAR Hack[15]; \
+ EX_PUSH_LOCK_WAIT_BLOCK UnalignedBlock; \
+ } WaitBlockBuffer; \
+ PEX_PUSH_LOCK_WAIT_BLOCK x = (PEX_PUSH_LOCK_WAIT_BLOCK) \
+ ((ULONG_PTR)&WaitBlockBuffer.UnalignedBlock &~ 0xF);
+
+#else
+
+//
+// This is only for compatibility; the compiler will optimize the extra
+// local variable (the actual pointer) away, so we don't take any perf hit
+// by doing this.
+//
+#define DEFINE_WAIT_BLOCK(x) \
+ EX_PUSH_LOCK_WAIT_BLOCK WaitBlockBuffer; \
+ PEX_PUSH_LOCK_WAIT_BLOCK x = &WaitBlockBuffer;
+
+#endif
+
/* INITIALIZATION FUNCTIONS *************************************************/
VOID
@@ -596,6 +626,23 @@
/* PUSHLOCKS *****************************************************************/
+/* FIXME: VERIFY THESE! */
+
+VOID
+FASTCALL
+ExBlockPushLock(PEX_PUSH_LOCK PushLock,
+ PVOID WaitBlock);
+
+VOID
+FASTCALL
+ExfUnblockPushLock(PEX_PUSH_LOCK PushLock,
+ PVOID CurrentWaitBlock);
+
+VOID
+FASTCALL
+ExWaitForUnblockPushLock(IN PEX_PUSH_LOCK PushLock,
+ IN PEX_PUSH_LOCK_WAIT_BLOCK WaitBlock);
+
/*++
* @name ExInitializePushLock
* INTERNAL MACRO
@@ -751,12 +798,16 @@
FORCEINLINE
ExWaitOnPushLock(PEX_PUSH_LOCK PushLock)
{
- /* Acquire the lock */
- ExfAcquirePushLockExclusive(PushLock);
- ASSERT(PushLock->Locked);
-
- /* Release it */
- ExfReleasePushLockExclusive(PushLock);
+ /* Check if we're locked */
+ if (PushLock->Locked)
+ {
+ /* Acquire the lock */
+ ExfAcquirePushLockExclusive(PushLock);
+ ASSERT(PushLock->Locked);
+
+ /* Release it */
+ ExfReleasePushLockExclusive(PushLock);
+ }
}
/*++