/** @file\r
Implementation of synchronization functions.\r
\r
- Copyright (c) 2006 - 2010, Intel Corporation. All rights reserved.<BR>\r
+ Copyright (c) 2006 - 2016, Intel Corporation. All rights reserved.<BR>\r
Portions copyright (c) 2008 - 2009, Apple Inc. All rights reserved.<BR>\r
This program and the accompanying materials\r
are licensed and made available under the terms and conditions of the BSD License\r
optimal spin lock performance.\r
\r
This function retrieves the spin lock alignment requirements for optimal\r
- performance on a given CPU architecture. The spin lock alignment must be a\r
- power of two and is returned by this function. If there are no alignment\r
+ performance on a given CPU architecture. The spin lock alignment is byte alignment. \r
+ It must be a power of two and is returned by this function. If there are no alignment\r
requirements, then 1 must be returned. The spin lock synchronization\r
functions must function correctly if the spin lock size and alignment values\r
returned by this function are not used at all. These values are hints to the\r
VOID\r
)\r
{\r
- return 32;\r
+ return InternalGetSpinLockProperties ();\r
}\r
\r
/**\r
INT64 Cycle;\r
INT64 Delta;\r
\r
- if (PcdGet32 (PcdSpinLockTimeout) > 0) {\r
+ if (PcdGet32 (PcdSpinLockTimeout) == 0) {\r
+ while (!AcquireSpinLockOrFail (SpinLock)) {\r
+ CpuPause ();\r
+ }\r
+ } else if (!AcquireSpinLockOrFail (SpinLock)) {\r
//\r
// Get the current timer value\r
//\r
Total += Delta;\r
ASSERT (Total < Timeout);\r
}\r
- } else {\r
- while (!AcquireSpinLockOrFail (SpinLock)) {\r
- CpuPause ();\r
- }\r
}\r
return SpinLock;\r
}\r
UINT32\r
EFIAPI\r
InterlockedIncrement (\r
- IN UINT32 *Value\r
+ IN volatile UINT32 *Value\r
)\r
{\r
ASSERT (Value != NULL);\r
UINT32\r
EFIAPI\r
InterlockedDecrement (\r
- IN UINT32 *Value\r
+ IN volatile UINT32 *Value\r
)\r
{\r
ASSERT (Value != NULL);\r
return InternalSyncDecrement (Value);\r
}\r
\r
+/**\r
+ Performs an atomic compare exchange operation on a 16-bit unsigned integer.\r
+\r
+ Performs an atomic compare exchange operation on the 16-bit unsigned integer\r
+ specified by Value. If Value is equal to CompareValue, then Value is set to\r
+ ExchangeValue and CompareValue is returned. If Value is not equal to CompareValue,\r
+ then Value is returned. The compare exchange operation must be performed using\r
+ MP safe mechanisms.\r
+\r
+ If Value is NULL, then ASSERT().\r
+\r
+ @param Value A pointer to the 16-bit value for the compare exchange\r
+ operation.\r
+ @param CompareValue A 16-bit value used in compare operation.\r
+ @param ExchangeValue A 16-bit value used in exchange operation.\r
+\r
+ @return The original *Value before exchange.\r
+\r
+**/\r
+UINT16\r
+EFIAPI\r
+InterlockedCompareExchange16 (\r
+ IN OUT volatile UINT16 *Value,\r
+ IN UINT16 CompareValue,\r
+ IN UINT16 ExchangeValue\r
+ )\r
+{\r
+ ASSERT (Value != NULL);\r
+ return InternalSyncCompareExchange16 (Value, CompareValue, ExchangeValue);\r
+}\r
+\r
/**\r
Performs an atomic compare exchange operation on a 32-bit unsigned integer.\r
\r
UINT32\r
EFIAPI\r
InterlockedCompareExchange32 (\r
- IN OUT UINT32 *Value,\r
+ IN OUT volatile UINT32 *Value,\r
IN UINT32 CompareValue,\r
IN UINT32 ExchangeValue\r
)\r
UINT64\r
EFIAPI\r
InterlockedCompareExchange64 (\r
- IN OUT UINT64 *Value,\r
+ IN OUT volatile UINT64 *Value,\r
IN UINT64 CompareValue,\r
IN UINT64 ExchangeValue\r
)\r
VOID *\r
EFIAPI\r
InterlockedCompareExchangePointer (\r
- IN OUT VOID **Value,\r
+ IN OUT VOID * volatile *Value,\r
IN VOID *CompareValue,\r
IN VOID *ExchangeValue\r
)\r
switch (SizeOfValue) {\r
case sizeof (UINT32):\r
return (VOID*)(UINTN)InterlockedCompareExchange32 (\r
- (UINT32*)Value,\r
+ (volatile UINT32 *)Value,\r
(UINT32)(UINTN)CompareValue,\r
(UINT32)(UINTN)ExchangeValue\r
);\r
case sizeof (UINT64):\r
return (VOID*)(UINTN)InterlockedCompareExchange64 (\r
- (UINT64*)Value,\r
+ (volatile UINT64 *)Value,\r
(UINT64)(UINTN)CompareValue,\r
(UINT64)(UINTN)ExchangeValue\r
);\r