diff options
Diffstat (limited to 'MdePkg/Library/BaseSynchronizationLib/Synchronization.c')
| -rw-r--r-- | MdePkg/Library/BaseSynchronizationLib/Synchronization.c | 387 |
1 files changed, 387 insertions, 0 deletions
diff --git a/MdePkg/Library/BaseSynchronizationLib/Synchronization.c b/MdePkg/Library/BaseSynchronizationLib/Synchronization.c new file mode 100644 index 0000000000..722525177c --- /dev/null +++ b/MdePkg/Library/BaseSynchronizationLib/Synchronization.c @@ -0,0 +1,387 @@ +/** @file
+ Implementation of synchronization functions.
+
+ Copyright (c) 2006 - 2008, 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.
+
+**/
+
+#include "BaseSynchronizationLibInternals.h"
+
+#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
+ )
+{
+ 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 in release state.
+
+**/
+SPIN_LOCK *
+EFIAPI
+InitializeSpinLock (
+ OUT SPIN_LOCK *SpinLock
+ )
+{
+ ASSERT (SpinLock != NULL);
+ *SpinLock = SPIN_LOCK_RELEASED;
+ 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 acquired lock.
+
+**/
+SPIN_LOCK *
+EFIAPI
+AcquireSpinLock (
+ IN OUT SPIN_LOCK *SpinLock
+ )
+{
+ UINT64 Current;
+ UINT64 Previous;
+ UINT64 Total;
+ UINT64 Start;
+ UINT64 End;
+ UINT64 Timeout;
+ INT64 Cycle;
+ INT64 Delta;
+
+ if (PcdGet32 (PcdSpinLockTimeout) > 0) {
+ //
+ // Get the current timer value
+ //
+ Current = GetPerformanceCounter();
+
+ //
+ // Initialize local variables
+ //
+ Start = 0;
+ End = 0;
+ Total = 0;
+
+ //
+ // Retrieve the performance counter properties and compute the number of performance
+ // counter ticks required to reach the timeout
+ //
+ Timeout = DivU64x32 (
+ MultU64x32 (
+ GetPerformanceCounterProperties (&Start, &End),
+ PcdGet32 (PcdSpinLockTimeout)
+ ),
+ 1000000
+ );
+ Cycle = End - Start;
+ if (Cycle < 0) {
+ Cycle = -Cycle;
+ }
+ Cycle++;
+
+ while (!AcquireSpinLockOrFail (SpinLock)) {
+ CpuPause ();
+ Previous = Current;
+ Current = GetPerformanceCounter();
+ Delta = (INT64) (Current - Previous);
+ if (Start > End) {
+ Delta = -Delta;
+ }
+ if (Delta < 0) {
+ Delta += Cycle;
+ }
+ Total += Delta;
+ ASSERT (Total < Timeout);
+ }
+ } else {
+ while (!AcquireSpinLockOrFail (SpinLock)) {
+ CpuPause ();
+ }
+ }
+ 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
+ )
+{
+ SPIN_LOCK LockValue;
+
+ ASSERT (SpinLock != NULL);
+
+ LockValue = *SpinLock;
+ ASSERT (SPIN_LOCK_ACQUIRED == LockValue || SPIN_LOCK_RELEASED == LockValue);
+
+ return (BOOLEAN)(
+ InterlockedCompareExchangePointer (
+ (VOID**)SpinLock,
+ (VOID*)SPIN_LOCK_RELEASED,
+ (VOID*)SPIN_LOCK_ACQUIRED
+ ) == (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 released lock.
+
+**/
+SPIN_LOCK *
+EFIAPI
+ReleaseSpinLock (
+ IN OUT SPIN_LOCK *SpinLock
+ )
+{
+ SPIN_LOCK LockValue;
+
+ ASSERT (SpinLock != NULL);
+
+ LockValue = *SpinLock;
+ ASSERT (SPIN_LOCK_ACQUIRED == LockValue || SPIN_LOCK_RELEASED == LockValue);
+
+ *SpinLock = SPIN_LOCK_RELEASED;
+ 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.
+
+ @return The original *Value before exchange.
+**/
+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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