X-Git-Url: https://git.proxmox.com/?a=blobdiff_plain;f=MdePkg%2FLibrary%2FBaseLib%2FSynchronization.c;h=503313322424a30c97b24feeba6ba17c72448727;hb=c9708dddc1a2d10725860d5e9ac1b4929d0b43f4;hp=df395869a295a1b8f0675caaf5624e3b55152ef0;hpb=878ddf1fc3540a715f63594ed22b6929e881afb4;p=mirror_edk2.git

diff --git a/MdePkg/Library/BaseLib/Synchronization.c b/MdePkg/Library/BaseLib/Synchronization.c
index df395869a2..5033133224 100644
--- a/MdePkg/Library/BaseLib/Synchronization.c
+++ b/MdePkg/Library/BaseLib/Synchronization.c
@@ -14,21 +14,64 @@
 
 **/
 
-#define SPIN_LOCK_RELEASED          ((SPIN_LOCK)0)
-#define SPIN_LOCK_ACQUIRED          ((SPIN_LOCK)-1)
+#define SPIN_LOCK_RELEASED          ((SPIN_LOCK)1)
+#define SPIN_LOCK_ACQUIRED          ((SPIN_LOCK)2)
 
+/**
+  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.
+
+  @param  Value A pointer to the 32-bit value to increment.
+
+  @return The incremented value.
+
+**/
 UINT32
 EFIAPI
 InternalSyncIncrement (
   IN      volatile UINT32           *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 decrement value. The decrement operation must be
+  performed using MP safe mechanisms. The state of the return value is not
+  guaranteed to be MP safe.
+
+  @param  Value A pointer to the 32-bit value to decrement.
+
+  @return The decrement value.
+
+**/
 UINT32
 EFIAPI
 InternalSyncDecrement (
   IN      volatile UINT32           *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.
+
+  @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
 InternalSyncCompareExchange32 (
@@ -37,6 +80,22 @@ InternalSyncCompareExchange32 (
   IN      UINT32                    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.
+
+  @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
 InternalSyncCompareExchange64 (
@@ -94,7 +153,7 @@ InitializeSpinLock (
   )
 {
   ASSERT (SpinLock != NULL);
-  *SpinLock = 0;
+  *SpinLock = SPIN_LOCK_RELEASED;
   return SpinLock;
 }
 
@@ -131,12 +190,12 @@ AcquireSpinLock (
   Tick = 0;
   Start = 0;
   End = 0;
-  if (FixedPcdGet32 (PcdSpinLockTimeout) > 0) {
+  if (PcdGet32 (PcdSpinLockTimeout) > 0) {
     Tick = GetPerformanceCounter ();
     Timeout = DivU64x32 (
                 MultU64x32 (
                   GetPerformanceCounterProperties (&Start, &End),
-                  FixedPcdGet32 (PcdSpinLockTimeout)
+                  PcdGet32 (PcdSpinLockTimeout)
                   ),
                 1000000
                 );
@@ -177,7 +236,13 @@ AcquireSpinLockOrFail (
   IN OUT  SPIN_LOCK                 *SpinLock
   )
 {
+  SPIN_LOCK    LockValue;
+
   ASSERT (SpinLock != NULL);
+
+  LockValue = *SpinLock;
+  ASSERT (LockValue == SPIN_LOCK_ACQUIRED || LockValue == SPIN_LOCK_RELEASED);
+
   return (BOOLEAN)(
            InterlockedCompareExchangePointer (
              (VOID**)SpinLock,
@@ -207,8 +272,14 @@ ReleaseSpinLock (
   IN OUT  SPIN_LOCK                 *SpinLock
   )
 {
+  SPIN_LOCK    LockValue;
+
   ASSERT (SpinLock != NULL);
-  *SpinLock = 0;
+
+  LockValue = *SpinLock;
+  ASSERT (LockValue == SPIN_LOCK_ACQUIRED || LockValue == SPIN_LOCK_RELEASED);
+
+  *SpinLock = SPIN_LOCK_RELEASED;
   return SpinLock;
 }
 
@@ -265,6 +336,14 @@ InterlockedDecrement (
 /**
   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.
@@ -276,7 +355,7 @@ InterlockedDecrement (
 UINT32
 EFIAPI
 InterlockedCompareExchange32 (
-  IN      UINT32                    *Value,
+  IN OUT  UINT32                    *Value,
   IN      UINT32                    CompareValue,
   IN      UINT32                    ExchangeValue
   )
@@ -288,6 +367,13 @@ InterlockedCompareExchange32 (
 /**
   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.
@@ -299,7 +385,7 @@ InterlockedCompareExchange32 (
 UINT64
 EFIAPI
 InterlockedCompareExchange64 (
-  IN      UINT64                    *Value,
+  IN OUT  UINT64                    *Value,
   IN      UINT64                    CompareValue,
   IN      UINT64                    ExchangeValue
   )
@@ -328,7 +414,7 @@ InterlockedCompareExchange64 (
 VOID *
 EFIAPI
 InterlockedCompareExchangePointer (
-  IN      VOID                      **Value,
+  IN OUT  VOID                      **Value,
   IN      VOID                      *CompareValue,
   IN      VOID                      *ExchangeValue
   )