diff options
| author | yshang1 <yshang1@6f19259b-4bc3-4df7-8a09-765794883524> | 2007-04-03 06:25:25 +0000 |
|---|---|---|
| committer | yshang1 <yshang1@6f19259b-4bc3-4df7-8a09-765794883524> | 2007-04-03 06:25:25 +0000 |
| commit | ef7baf58d031adb9aad451f761a1898190f482f5 (patch) | |
| tree | 9c0dc64301ac32c4174fa27005d0f10499236396 /MdePkg/Library/BaseLib/SynchronizationGcc.c | |
| parent | 9471ecb798ad67b8e53e6b2bcaf56ef5d83162e6 (diff) | |
| download | edk2-platforms-ef7baf58d031adb9aad451f761a1898190f482f5.tar.xz | |
Add the ReadWriteBarrier in the Acquire/ReleaseSpin to block the unexpected optimization of compiler.
git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@2524 6f19259b-4bc3-4df7-8a09-765794883524
Diffstat (limited to 'MdePkg/Library/BaseLib/SynchronizationGcc.c')
| -rw-r--r-- | MdePkg/Library/BaseLib/SynchronizationGcc.c | 366 |
1 files changed, 366 insertions, 0 deletions
diff --git a/MdePkg/Library/BaseLib/SynchronizationGcc.c b/MdePkg/Library/BaseLib/SynchronizationGcc.c new file mode 100644 index 0000000000..9d57a1f34d --- /dev/null +++ b/MdePkg/Library/BaseLib/SynchronizationGcc.c @@ -0,0 +1,366 @@ +/** @file
+ Implementation of synchronization functions.
+
+ Copyright (c) 2006 - 2007, Intel Corporation<BR>
+ All rights reserved. This program and the accompanying materials
+ are licensed and made available under the terms and conditions of the BSD License
+ which accompanies this distribution. The full text of the license may be found at
+ http://opensource.org/licenses/bsd-license.php
+
+ THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
+ WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
+
+ Module Name: SynchronizationGcc.c
+
+**/
+
+#include "BaseLibInternals.h"
+
+//
+// GCC inline assembly for Read Write Barrier
+//
+#define _ReadWriteBarrier() do { asm volatile ("": : : "memory"); } while(0)
+
+#define SPIN_LOCK_RELEASED ((UINTN) 1)
+#define SPIN_LOCK_ACQUIRED ((UINTN) 2)
+
+/**
+ Retrieves the architecture specific spin lock alignment requirements for
+ optimal spin lock performance.
+
+ This function retrieves the spin lock alignment requirements for optimal
+ performance on a given CPU architecture. The spin lock alignment must be a
+ power of two and is returned by this function. If there are no alignment
+ requirements, then 1 must be returned. The spin lock synchronization
+ functions must function correctly if the spin lock size and alignment values
+ returned by this function are not used at all. These values are hints to the
+ consumers of the spin lock synchronization functions to obtain optimal spin
+ lock performance.
+
+ @return The architecture specific spin lock alignment.
+
+**/
+UINTN
+EFIAPI
+GetSpinLockProperties (
+ VOID
+ )
+{
+ // @bug May use a PCD entry to determine this alignment.
+ return 32;
+}
+
+/**
+ Initializes a spin lock to the released state and returns the spin lock.
+
+ This function initializes the spin lock specified by SpinLock to the released
+ state, and returns SpinLock. Optimal performance can be achieved by calling
+ GetSpinLockProperties() to determine the size and alignment requirements for
+ SpinLock.
+
+ If SpinLock is NULL, then ASSERT().
+
+ @param SpinLock A pointer to the spin lock to initialize to the released
+ state.
+
+ @return SpinLock
+
+**/
+SPIN_LOCK *
+EFIAPI
+InitializeSpinLock (
+ OUT SPIN_LOCK *SpinLock
+ )
+{
+ ASSERT (SpinLock != NULL);
+
+ _ReadWriteBarrier();
+ *SpinLock = SPIN_LOCK_RELEASED;
+ _ReadWriteBarrier();
+
+ return SpinLock;
+}
+
+/**
+ Waits until a spin lock can be placed in the acquired state.
+
+ This function checks the state of the spin lock specified by SpinLock. If
+ SpinLock is in the released state, then this function places SpinLock in the
+ acquired state and returns SpinLock. Otherwise, this function waits
+ indefinitely for the spin lock to be released, and then places it in the
+ acquired state and returns SpinLock. All state transitions of SpinLock must
+ be performed using MP safe mechanisms.
+
+ If SpinLock is NULL, then ASSERT().
+ If SpinLock was not initialized with InitializeSpinLock(), then ASSERT().
+ If PcdSpinLockTimeout is not zero, and SpinLock is can not be acquired in
+ PcdSpinLockTimeout microseconds, then ASSERT().
+
+ @param SpinLock A pointer to the spin lock to place in the acquired state.
+
+ @return SpinLock
+
+**/
+SPIN_LOCK *
+EFIAPI
+AcquireSpinLock (
+ IN OUT SPIN_LOCK *SpinLock
+ )
+{
+ UINT64 Tick;
+ UINT64 Start, End;
+ UINT64 Timeout;
+
+ Tick = 0;
+ Start = 0;
+ End = 0;
+ if (PcdGet32 (PcdSpinLockTimeout) > 0) {
+ Tick = GetPerformanceCounter ();
+ Timeout = DivU64x32 (
+ MultU64x32 (
+ GetPerformanceCounterProperties (&Start, &End),
+ PcdGet32 (PcdSpinLockTimeout)
+ ),
+ 1000000
+ );
+ if (Start < End) {
+ Tick += Timeout;
+ } else {
+ Tick -= Timeout;
+ }
+ }
+
+ while (!AcquireSpinLockOrFail (SpinLock)) {
+ CpuPause ();
+ ASSERT ((Start < End) ^ (Tick <= GetPerformanceCounter ()));
+ }
+ return SpinLock;
+}
+
+/**
+ Attempts to place a spin lock in the acquired state.
+
+ This function checks the state of the spin lock specified by SpinLock. If
+ SpinLock is in the released state, then this function places SpinLock in the
+ acquired state and returns TRUE. Otherwise, FALSE is returned. All state
+ transitions of SpinLock must be performed using MP safe mechanisms.
+
+ If SpinLock is NULL, then ASSERT().
+ If SpinLock was not initialized with InitializeSpinLock(), then ASSERT().
+
+ @param SpinLock A pointer to the spin lock to place in the acquired state.
+
+ @retval TRUE SpinLock was placed in the acquired state.
+ @retval FALSE SpinLock could not be acquired.
+
+**/
+BOOLEAN
+EFIAPI
+AcquireSpinLockOrFail (
+ IN OUT SPIN_LOCK *SpinLock
+ )
+{
+ VOID *Result;
+
+ ASSERT (SpinLock != NULL);
+ ASSERT (*SpinLock == SPIN_LOCK_ACQUIRED || *SpinLock == SPIN_LOCK_RELEASED);
+
+ _ReadWriteBarrier ();
+ Result = InterlockedCompareExchangePointer (
+ (VOID**)SpinLock,
+ (VOID*)SPIN_LOCK_RELEASED,
+ (VOID*)SPIN_LOCK_ACQUIRED
+ );
+
+ _ReadWriteBarrier ();
+ return (BOOLEAN) (Result == (VOID*) SPIN_LOCK_RELEASED);
+}
+
+/**
+ Releases a spin lock.
+
+ This function places the spin lock specified by SpinLock in the release state
+ and returns SpinLock.
+
+ If SpinLock is NULL, then ASSERT().
+ If SpinLock was not initialized with InitializeSpinLock(), then ASSERT().
+
+ @param SpinLock A pointer to the spin lock to release.
+
+ @return SpinLock
+
+**/
+SPIN_LOCK *
+EFIAPI
+ReleaseSpinLock (
+ IN OUT SPIN_LOCK *SpinLock
+ )
+{
+ ASSERT (SpinLock != NULL);
+ ASSERT (*SpinLock == SPIN_LOCK_ACQUIRED || *SpinLock == SPIN_LOCK_RELEASED);
+
+ _ReadWriteBarrier ();
+ *SpinLock = SPIN_LOCK_RELEASED;
+ _ReadWriteBarrier ();
+
+ return SpinLock;
+}
+
+/**
+ Performs an atomic increment of an 32-bit unsigned integer.
+
+ Performs an atomic increment of the 32-bit unsigned integer specified by
+ Value and returns the incremented value. The increment operation must be
+ performed using MP safe mechanisms. The state of the return value is not
+ guaranteed to be MP safe.
+
+ If Value is NULL, then ASSERT().
+
+ @param Value A pointer to the 32-bit value to increment.
+
+ @return The incremented value.
+
+**/
+UINT32
+EFIAPI
+InterlockedIncrement (
+ IN UINT32 *Value
+ )
+{
+ ASSERT (Value != NULL);
+ return InternalSyncIncrement (Value);
+}
+
+/**
+ Performs an atomic decrement of an 32-bit unsigned integer.
+
+ Performs an atomic decrement of the 32-bit unsigned integer specified by
+ Value and returns the decremented value. The decrement operation must be
+ performed using MP safe mechanisms. The state of the return value is not
+ guaranteed to be MP safe.
+
+ If Value is NULL, then ASSERT().
+
+ @param Value A pointer to the 32-bit value to decrement.
+
+ @return The decremented value.
+
+**/
+UINT32
+EFIAPI
+InterlockedDecrement (
+ IN UINT32 *Value
+ )
+{
+ ASSERT (Value != NULL);
+ return InternalSyncDecrement (Value);
+}
+
+/**
+ Performs an atomic compare exchange operation on a 32-bit unsigned integer.
+
+ Performs an atomic compare exchange operation on the 32-bit unsigned integer
+ specified by Value. If Value is equal to CompareValue, then Value is set to
+ ExchangeValue and CompareValue is returned. If Value is not equal to CompareValue,
+ then Value is returned. The compare exchange operation must be performed using
+ MP safe mechanisms.
+
+ If Value is NULL, then ASSERT().
+
+ @param Value A pointer to the 32-bit value for the compare exchange
+ operation.
+ @param CompareValue 32-bit value used in compare operation.
+ @param ExchangeValue 32-bit value used in exchange operation.
+
+ @return The original *Value before exchange.
+
+**/
+UINT32
+EFIAPI
+InterlockedCompareExchange32 (
+ IN OUT UINT32 *Value,
+ IN UINT32 CompareValue,
+ IN UINT32 ExchangeValue
+ )
+{
+ ASSERT (Value != NULL);
+ return InternalSyncCompareExchange32 (Value, CompareValue, ExchangeValue);
+}
+
+/**
+ Performs an atomic compare exchange operation on a 64-bit unsigned integer.
+
+ Performs an atomic compare exchange operation on the 64-bit unsigned integer specified
+ by Value. If Value is equal to CompareValue, then Value is set to ExchangeValue and
+ CompareValue is returned. If Value is not equal to CompareValue, then Value is returned.
+ The compare exchange operation must be performed using MP safe mechanisms.
+
+ If Value is NULL, then ASSERT().
+
+ @param Value A pointer to the 64-bit value for the compare exchange
+ operation.
+ @param CompareValue 64-bit value used in compare operation.
+ @param ExchangeValue 64-bit value used in exchange operation.
+
+ @return The original *Value before exchange.
+
+**/
+UINT64
+EFIAPI
+InterlockedCompareExchange64 (
+ IN OUT UINT64 *Value,
+ IN UINT64 CompareValue,
+ IN UINT64 ExchangeValue
+ )
+{
+ ASSERT (Value != NULL);
+ return InternalSyncCompareExchange64 (Value, CompareValue, ExchangeValue);
+}
+
+/**
+ Performs an atomic compare exchange operation on a pointer value.
+
+ Performs an atomic compare exchange operation on the pointer value specified
+ by Value. If Value is equal to CompareValue, then Value is set to
+ ExchangeValue and CompareValue is returned. If Value is not equal to
+ CompareValue, then Value is returned. The compare exchange operation must be
+ performed using MP safe mechanisms.
+
+ If Value is NULL, then ASSERT().
+
+ @param Value A pointer to the pointer value for the compare exchange
+ operation.
+ @param CompareValue Pointer value used in compare operation.
+ @param ExchangeValue Pointer value used in exchange operation.
+
+**/
+VOID *
+EFIAPI
+InterlockedCompareExchangePointer (
+ IN OUT VOID **Value,
+ IN VOID *CompareValue,
+ IN VOID *ExchangeValue
+ )
+{
+ UINT8 SizeOfValue;
+
+ SizeOfValue = sizeof (*Value);
+
+ switch (SizeOfValue) {
+ case sizeof (UINT32):
+ return (VOID*)(UINTN)InterlockedCompareExchange32 (
+ (UINT32*)Value,
+ (UINT32)(UINTN)CompareValue,
+ (UINT32)(UINTN)ExchangeValue
+ );
+ case sizeof (UINT64):
+ return (VOID*)(UINTN)InterlockedCompareExchange64 (
+ (UINT64*)Value,
+ (UINT64)(UINTN)CompareValue,
+ (UINT64)(UINTN)ExchangeValue
+ );
+ default:
+ ASSERT (FALSE);
+ return NULL;
+ }
+}
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