+++ /dev/null
-/** @file\r
- Implementation of synchronization functions.\r
-\r
- Copyright (c) 2006, Intel Corporation<BR>\r
- All rights reserved. This program and the accompanying materials\r
- are licensed and made available under the terms and conditions of the BSD License\r
- which accompanies this distribution. The full text of the license may be found at\r
- http://opensource.org/licenses/bsd-license.php\r
-\r
- THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,\r
- WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.\r
-\r
- Module Name: Synchronization.c\r
-\r
-**/\r
-\r
-#include "BaseLibInternals.h"\r
-\r
-#define SPIN_LOCK_RELEASED ((UINTN) 1)\r
-#define SPIN_LOCK_ACQUIRED ((UINTN) 2)\r
-\r
-/**\r
- Retrieves the architecture specific spin lock alignment requirements for\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
- 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
- consumers of the spin lock synchronization functions to obtain optimal spin\r
- lock performance.\r
-\r
- @return The architecture specific spin lock alignment.\r
-\r
-**/\r
-UINTN\r
-EFIAPI\r
-GetSpinLockProperties (\r
- VOID\r
- )\r
-{\r
- // @bug May use a PCD entry to determine this alignment.\r
- return 32;\r
-}\r
-\r
-/**\r
- Initializes a spin lock to the released state and returns the spin lock.\r
-\r
- This function initializes the spin lock specified by SpinLock to the released\r
- state, and returns SpinLock. Optimal performance can be achieved by calling\r
- GetSpinLockProperties() to determine the size and alignment requirements for\r
- SpinLock.\r
-\r
- If SpinLock is NULL, then ASSERT().\r
-\r
- @param SpinLock A pointer to the spin lock to initialize to the released\r
- state.\r
-\r
- @return SpinLock\r
-\r
-**/\r
-SPIN_LOCK *\r
-EFIAPI\r
-InitializeSpinLock (\r
- OUT SPIN_LOCK *SpinLock\r
- )\r
-{\r
- ASSERT (SpinLock != NULL);\r
- *SpinLock = SPIN_LOCK_RELEASED;\r
- return SpinLock;\r
-}\r
-\r
-/**\r
- Waits until a spin lock can be placed in the acquired state.\r
-\r
- This function checks the state of the spin lock specified by SpinLock. If\r
- SpinLock is in the released state, then this function places SpinLock in the\r
- acquired state and returns SpinLock. Otherwise, this function waits\r
- indefinitely for the spin lock to be released, and then places it in the\r
- acquired state and returns SpinLock. All state transitions of SpinLock must\r
- be performed using MP safe mechanisms.\r
-\r
- If SpinLock is NULL, then ASSERT().\r
- If SpinLock was not initialized with InitializeSpinLock(), then ASSERT().\r
- If PcdSpinLockTimeout is not zero, and SpinLock is can not be acquired in\r
- PcdSpinLockTimeout microseconds, then ASSERT().\r
-\r
- @param SpinLock A pointer to the spin lock to place in the acquired state.\r
-\r
- @return SpinLock\r
-\r
-**/\r
-SPIN_LOCK *\r
-EFIAPI\r
-AcquireSpinLock (\r
- IN OUT SPIN_LOCK *SpinLock\r
- )\r
-{\r
- UINT64 Tick;\r
- UINT64 Start, End;\r
- UINT64 Timeout;\r
-\r
- Tick = 0;\r
- Start = 0;\r
- End = 0;\r
- if (PcdGet32 (PcdSpinLockTimeout) > 0) {\r
- Tick = GetPerformanceCounter ();\r
- Timeout = DivU64x32 (\r
- MultU64x32 (\r
- GetPerformanceCounterProperties (&Start, &End),\r
- PcdGet32 (PcdSpinLockTimeout)\r
- ),\r
- 1000000\r
- );\r
- if (Start < End) {\r
- Tick += Timeout;\r
- } else {\r
- Tick -= Timeout;\r
- }\r
- }\r
-\r
- while (!AcquireSpinLockOrFail (SpinLock)) {\r
- CpuPause ();\r
- ASSERT ((Start < End) ^ (Tick <= GetPerformanceCounter ()));\r
- }\r
- return SpinLock;\r
-}\r
-\r
-/**\r
- Attempts to place a spin lock in the acquired state.\r
-\r
- This function checks the state of the spin lock specified by SpinLock. If\r
- SpinLock is in the released state, then this function places SpinLock in the\r
- acquired state and returns TRUE. Otherwise, FALSE is returned. All state\r
- transitions of SpinLock must be performed using MP safe mechanisms.\r
-\r
- If SpinLock is NULL, then ASSERT().\r
- If SpinLock was not initialized with InitializeSpinLock(), then ASSERT().\r
-\r
- @param SpinLock A pointer to the spin lock to place in the acquired state.\r
-\r
- @retval TRUE SpinLock was placed in the acquired state.\r
- @retval FALSE SpinLock could not be acquired.\r
-\r
-**/\r
-BOOLEAN\r
-EFIAPI\r
-AcquireSpinLockOrFail (\r
- IN OUT SPIN_LOCK *SpinLock\r
- )\r
-{\r
- SPIN_LOCK LockValue;\r
-\r
- ASSERT (SpinLock != NULL);\r
-\r
- LockValue = *SpinLock;\r
- ASSERT (LockValue == SPIN_LOCK_ACQUIRED || LockValue == SPIN_LOCK_RELEASED);\r
-\r
- return (BOOLEAN)(\r
- InterlockedCompareExchangePointer (\r
- (VOID**)SpinLock,\r
- (VOID*)SPIN_LOCK_RELEASED,\r
- (VOID*)SPIN_LOCK_ACQUIRED\r
- ) == (VOID*)SPIN_LOCK_RELEASED\r
- );\r
-}\r
-\r
-/**\r
- Releases a spin lock.\r
-\r
- This function places the spin lock specified by SpinLock in the release state\r
- and returns SpinLock.\r
-\r
- If SpinLock is NULL, then ASSERT().\r
- If SpinLock was not initialized with InitializeSpinLock(), then ASSERT().\r
-\r
- @param SpinLock A pointer to the spin lock to release.\r
-\r
- @return SpinLock\r
-\r
-**/\r
-SPIN_LOCK *\r
-EFIAPI\r
-ReleaseSpinLock (\r
- IN OUT SPIN_LOCK *SpinLock\r
- )\r
-{\r
- SPIN_LOCK LockValue;\r
-\r
- ASSERT (SpinLock != NULL);\r
-\r
- LockValue = *SpinLock;\r
- ASSERT (LockValue == SPIN_LOCK_ACQUIRED || LockValue == SPIN_LOCK_RELEASED);\r
-\r
- *SpinLock = SPIN_LOCK_RELEASED;\r
- return SpinLock;\r
-}\r
-\r
-/**\r
- Performs an atomic increment of an 32-bit unsigned integer.\r
-\r
- Performs an atomic increment of the 32-bit unsigned integer specified by\r
- Value and returns the incremented value. The increment operation must be\r
- performed using MP safe mechanisms. The state of the return value is not\r
- guaranteed to be MP safe.\r
-\r
- If Value is NULL, then ASSERT().\r
-\r
- @param Value A pointer to the 32-bit value to increment.\r
-\r
- @return The incremented value.\r
-\r
-**/\r
-UINT32\r
-EFIAPI\r
-InterlockedIncrement (\r
- IN UINT32 *Value\r
- )\r
-{\r
- ASSERT (Value != NULL);\r
- return InternalSyncIncrement (Value);\r
-}\r
-\r
-/**\r
- Performs an atomic decrement of an 32-bit unsigned integer.\r
-\r
- Performs an atomic decrement of the 32-bit unsigned integer specified by\r
- Value and returns the decremented value. The decrement operation must be\r
- performed using MP safe mechanisms. The state of the return value is not\r
- guaranteed to be MP safe.\r
-\r
- If Value is NULL, then ASSERT().\r
-\r
- @param Value A pointer to the 32-bit value to decrement.\r
-\r
- @return The decremented value.\r
-\r
-**/\r
-UINT32\r
-EFIAPI\r
-InterlockedDecrement (\r
- IN UINT32 *Value\r
- )\r
-{\r
- ASSERT (Value != NULL);\r
- return InternalSyncDecrement (Value);\r
-}\r
-\r
-/**\r
- Performs an atomic compare exchange operation on a 32-bit unsigned integer.\r
-\r
- Performs an atomic compare exchange operation on the 32-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 32-bit value for the compare exchange\r
- operation.\r
- @param CompareValue 32-bit value used in compare operation.\r
- @param ExchangeValue 32-bit value used in exchange operation.\r
-\r
- @return The original *Value before exchange.\r
-\r
-**/\r
-UINT32\r
-EFIAPI\r
-InterlockedCompareExchange32 (\r
- IN OUT UINT32 *Value,\r
- IN UINT32 CompareValue,\r
- IN UINT32 ExchangeValue\r
- )\r
-{\r
- ASSERT (Value != NULL);\r
- return InternalSyncCompareExchange32 (Value, CompareValue, ExchangeValue);\r
-}\r
-\r
-/**\r
- Performs an atomic compare exchange operation on a 64-bit unsigned integer.\r
-\r
- Performs an atomic compare exchange operation on the 64-bit unsigned integer specified \r
- by Value. If Value is equal to CompareValue, then Value is set to ExchangeValue and \r
- CompareValue is returned. If Value is not equal to CompareValue, then Value is returned. \r
- The compare exchange operation must be performed using MP safe mechanisms.\r
-\r
- If Value is NULL, then ASSERT().\r
-\r
- @param Value A pointer to the 64-bit value for the compare exchange\r
- operation.\r
- @param CompareValue 64-bit value used in compare operation.\r
- @param ExchangeValue 64-bit value used in exchange operation.\r
-\r
- @return The original *Value before exchange.\r
-\r
-**/\r
-UINT64\r
-EFIAPI\r
-InterlockedCompareExchange64 (\r
- IN OUT UINT64 *Value,\r
- IN UINT64 CompareValue,\r
- IN UINT64 ExchangeValue\r
- )\r
-{\r
- ASSERT (Value != NULL);\r
- return InternalSyncCompareExchange64 (Value, CompareValue, ExchangeValue);\r
-}\r
-\r
-/**\r
- Performs an atomic compare exchange operation on a pointer value.\r
-\r
- Performs an atomic compare exchange operation on the pointer value specified\r
- 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\r
- CompareValue, then Value is returned. The compare exchange operation must be\r
- performed using MP safe mechanisms.\r
-\r
- If Value is NULL, then ASSERT().\r
-\r
- @param Value A pointer to the pointer value for the compare exchange\r
- operation.\r
- @param CompareValue Pointer value used in compare operation.\r
- @param ExchangeValue Pointer value used in exchange operation.\r
-\r
-**/\r
-VOID *\r
-EFIAPI\r
-InterlockedCompareExchangePointer (\r
- IN OUT VOID **Value,\r
- IN VOID *CompareValue,\r
- IN VOID *ExchangeValue\r
- )\r
-{\r
- UINT8 SizeOfValue;\r
-\r
- SizeOfValue = sizeof (*Value);\r
-\r
- switch (SizeOfValue) {\r
- case sizeof (UINT32):\r
- return (VOID*)(UINTN)InterlockedCompareExchange32 (\r
- (UINT32*)Value,\r
- (UINT32)(UINTN)CompareValue,\r
- (UINT32)(UINTN)ExchangeValue\r
- );\r
- case sizeof (UINT64):\r
- return (VOID*)(UINTN)InterlockedCompareExchange64 (\r
- (UINT64*)Value,\r
- (UINT64)(UINTN)CompareValue,\r
- (UINT64)(UINTN)ExchangeValue\r
- );\r
- default:\r
- ASSERT (FALSE);\r
- return NULL;\r
- }\r
-}\r
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