MdePkg/Include: Add volatile to SynchronizationLib parameters

[mirror_edk2.git] / MdePkg / Include / Library / SynchronizationLib.h

diff --git a/MdePkg/Include/Library/SynchronizationLib.h b/MdePkg/Include/Library/SynchronizationLib.h
index bf92ca1d7a9f8dfbd30ca715e8b6880a558ddee6..6cf3d71770e7e6fcd4f027ed4fb49a2f0ef6c2a4 100644 (file)
--- a/MdePkg/Include/Library/SynchronizationLib.h
+++ b/MdePkg/Include/Library/SynchronizationLib.h
@@ -1,8 +1,8 @@
 /** @file\r
   Provides synchronization functions.\r
 \r
-Copyright (c) 2006 - 2008, Intel Corporation<BR>\r
-All rights reserved. This program and the accompanying materials\r
+Copyright (c) 2006 - 2016, Intel Corporation. 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
 which accompanies this distribution.  The full text of the license may be found at\r
 http://opensource.org/licenses/bsd-license.php\r
@@ -22,19 +22,19 @@ typedef volatile UINTN              SPIN_LOCK;
 \r
 \r
 /**\r
-  Retrieves the architecture specific spin lock alignment requirements for\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
+  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
   consumers of the spin lock synchronization functions to obtain optimal spin\r
   lock performance.\r
 \r
-  @return The architecture specific spin lock alignment.\r
+  @return The architecture-specific spin lock alignment.\r
 \r
 **/\r
 UINTN\r
@@ -140,7 +140,7 @@ ReleaseSpinLock (
 \r
 \r
 /**\r
-  Performs an atomic increment of an 32-bit unsigned integer.\r
+  Performs an atomic increment of a 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
@@ -157,12 +157,12 @@ ReleaseSpinLock (
 UINT32\r
 EFIAPI\r
 InterlockedIncrement (\r
-  IN      UINT32                    *Value\r
+  IN      volatile UINT32           *Value\r
   );\r
 \r
 \r
 /**\r
-  Performs an atomic decrement of an 32-bit unsigned integer.\r
+  Performs an atomic decrement of a 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
@@ -179,10 +179,36 @@ InterlockedIncrement (
 UINT32\r
 EFIAPI\r
 InterlockedDecrement (\r
-  IN      UINT32                    *Value\r
+  IN      volatile UINT32           *Value\r
   );\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  16-bit value used in compare operation.\r
+  @param  ExchangeValue 16-bit value used in exchange operation.\r
+\r
+  @return The original *Value before exchange.\r
+**/\r
+UINT16\r
+EFIAPI\r
+InterlockedCompareExchange16 (\r
+  IN OUT  volatile UINT16           *Value,\r
+  IN      UINT16                    CompareValue,\r
+  IN      UINT16                    ExchangeValue\r
+  );\r
+\r
 /**\r
   Performs an atomic compare exchange operation on a 32-bit unsigned integer.\r
 \r
@@ -205,7 +231,7 @@ InterlockedDecrement (
 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
@@ -232,7 +258,7 @@ InterlockedCompareExchange32 (
 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
@@ -259,7 +285,7 @@ InterlockedCompareExchange64 (
 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