UefiCpuPkg/PiSmmCpuDxeSmm: Improve the performance of GetFreeToken()

[mirror_edk2.git] / UefiCpuPkg / PiSmmCpuDxeSmm / MpService.c

diff --git a/UefiCpuPkg/PiSmmCpuDxeSmm/MpService.c b/UefiCpuPkg/PiSmmCpuDxeSmm/MpService.c
index c285a70ebb9ab079822c959f6f7e0a8750018822..93cac5e4fa93235e5d294ea65055bca98e8ed69b 100644 (file)
--- a/UefiCpuPkg/PiSmmCpuDxeSmm/MpService.c
+++ b/UefiCpuPkg/PiSmmCpuDxeSmm/MpService.c
@@ -453,6 +453,11 @@ ResetTokens (
 \r
     Link = GetNextNode (&gSmmCpuPrivate->TokenList, Link);\r
   }\r
+\r
+  //\r
+  // Reset the FirstFreeToken to the beginning of token list upon exiting SMI.\r
+  //\r
+  gSmmCpuPrivate->FirstFreeToken = GetFirstNode (&gSmmCpuPrivate->TokenList);\r
 }\r
 \r
 /**\r
@@ -1060,23 +1065,21 @@ IsTokenInUse (
 /**\r
   Allocate buffer for the SPIN_LOCK and PROCEDURE_TOKEN.\r
 \r
+  @return First token of the token buffer.\r
 **/\r
-VOID\r
+LIST_ENTRY *\r
 AllocateTokenBuffer (\r
   VOID\r
   )\r
 {\r
   UINTN               SpinLockSize;\r
   UINT32              TokenCountPerChunk;\r
-  UINTN               ProcTokenSize;\r
   UINTN               Index;\r
-  PROCEDURE_TOKEN     *ProcToken;\r
   SPIN_LOCK           *SpinLock;\r
   UINT8               *SpinLockBuffer;\r
-  UINT8               *ProcTokenBuffer;\r
+  PROCEDURE_TOKEN     *ProcTokens;\r
 \r
   SpinLockSize = GetSpinLockProperties ();\r
-  ProcTokenSize = sizeof (PROCEDURE_TOKEN);\r
 \r
   TokenCountPerChunk = FixedPcdGet32 (PcdCpuSmmMpTokenCountPerChunk);\r
   ASSERT (TokenCountPerChunk != 0);\r
@@ -1092,49 +1095,22 @@ AllocateTokenBuffer (
   SpinLockBuffer = AllocatePool (SpinLockSize * TokenCountPerChunk);\r
   ASSERT (SpinLockBuffer != NULL);\r
 \r
-  ProcTokenBuffer = AllocatePool (ProcTokenSize * TokenCountPerChunk);\r
-  ASSERT (ProcTokenBuffer != NULL);\r
+  ProcTokens = AllocatePool (sizeof (PROCEDURE_TOKEN) * TokenCountPerChunk);\r
+  ASSERT (ProcTokens != NULL);\r
 \r
   for (Index = 0; Index < TokenCountPerChunk; Index++) {\r
     SpinLock = (SPIN_LOCK *)(SpinLockBuffer + SpinLockSize * Index);\r
     InitializeSpinLock (SpinLock);\r
 \r
-    ProcToken = (PROCEDURE_TOKEN *)(ProcTokenBuffer + ProcTokenSize * Index);\r
-    ProcToken->Signature = PROCEDURE_TOKEN_SIGNATURE;\r
-    ProcToken->SpinLock = SpinLock;\r
-    ProcToken->Used = FALSE;\r
-    ProcToken->RunningApCount = 0;\r
+    ProcTokens[Index].Signature      = PROCEDURE_TOKEN_SIGNATURE;\r
+    ProcTokens[Index].SpinLock       = SpinLock;\r
+    ProcTokens[Index].Used           = FALSE;\r
+    ProcTokens[Index].RunningApCount = 0;\r
 \r
-    InsertTailList (&gSmmCpuPrivate->TokenList, &ProcToken->Link);\r
+    InsertTailList (&gSmmCpuPrivate->TokenList, &ProcTokens[Index].Link);\r
   }\r
-}\r
 \r
-/**\r
-  Find first free token in the allocated token list.\r
-\r
-  @retval    return the first free PROCEDURE_TOKEN.\r
-\r
-**/\r
-PROCEDURE_TOKEN *\r
-FindFirstFreeToken (\r
-  VOID\r
-  )\r
-{\r
-  LIST_ENTRY        *Link;\r
-  PROCEDURE_TOKEN   *ProcToken;\r
-\r
-  Link = GetFirstNode (&gSmmCpuPrivate->TokenList);\r
-  while (!IsNull (&gSmmCpuPrivate->TokenList, Link)) {\r
-    ProcToken = PROCEDURE_TOKEN_FROM_LINK (Link);\r
-\r
-    if (!ProcToken->Used) {\r
-      return ProcToken;\r
-    }\r
-\r
-    Link = GetNextNode (&gSmmCpuPrivate->TokenList, Link);\r
-  }\r
-\r
-  return NULL;\r
+  return &ProcTokens[0].Link;\r
 }\r
 \r
 /**\r
@@ -1154,12 +1130,15 @@ GetFreeToken (
 {\r
   PROCEDURE_TOKEN  *NewToken;\r
 \r
-  NewToken = FindFirstFreeToken ();\r
-  if (NewToken == NULL) {\r
-    AllocateTokenBuffer ();\r
-    NewToken = FindFirstFreeToken ();\r
+  //\r
+  // If FirstFreeToken meets the end of token list, enlarge the token list.\r
+  // Set FirstFreeToken to the first free token.\r
+  //\r
+  if (gSmmCpuPrivate->FirstFreeToken == &gSmmCpuPrivate->TokenList) {\r
+    gSmmCpuPrivate->FirstFreeToken = AllocateTokenBuffer ();\r
   }\r
-  ASSERT (NewToken != NULL);\r
+  NewToken = PROCEDURE_TOKEN_FROM_LINK (gSmmCpuPrivate->FirstFreeToken);\r
+  gSmmCpuPrivate->FirstFreeToken = GetNextNode (&gSmmCpuPrivate->TokenList, gSmmCpuPrivate->FirstFreeToken);\r
 \r
   NewToken->Used = TRUE;\r
   NewToken->RunningApCount = RunningApsCount;\r
@@ -1781,7 +1760,7 @@ InitializeDataForMmMp (
 \r
   InitializeListHead (&gSmmCpuPrivate->TokenList);\r
 \r
-  AllocateTokenBuffer ();\r
+  gSmmCpuPrivate->FirstFreeToken = AllocateTokenBuffer ();\r
 }\r
 \r
 /**\r