UefiCpuPkg/CpuDxe: remove all code to flush TLB for APs

[mirror_edk2.git] / UefiCpuPkg / CpuDxe / CpuPageTable.c

diff --git a/UefiCpuPkg/CpuDxe/CpuPageTable.c b/UefiCpuPkg/CpuDxe/CpuPageTable.c
index a33ac5519e68cb733f334ceef264e103ce4293eb..e2595b4d892d948c50dfddc7843eaac1ff6b2ac2 100644 (file)
--- a/UefiCpuPkg/CpuDxe/CpuPageTable.c
+++ b/UefiCpuPkg/CpuDxe/CpuPageTable.c
@@ -89,70 +89,6 @@ PAGE_ATTRIBUTE_TABLE mPageAttributeTable[] = {
 \r
 PAGE_TABLE_POOL   *mPageTablePool = NULL;\r
 \r
-/**\r
-  Enable write protection function for AP.\r
-\r
-  @param[in,out] Buffer  The pointer to private data buffer.\r
-**/\r
-VOID\r
-EFIAPI\r
-SyncCpuEnableWriteProtection (\r
-  IN OUT VOID *Buffer\r
-  )\r
-{\r
-  AsmWriteCr0 (AsmReadCr0 () | BIT16);\r
-}\r
-\r
-/**\r
-  CpuFlushTlb function for AP.\r
-\r
-  @param[in,out] Buffer  The pointer to private data buffer.\r
-**/\r
-VOID\r
-EFIAPI\r
-SyncCpuFlushTlb (\r
-  IN OUT VOID *Buffer\r
-  )\r
-{\r
-  CpuFlushTlb();\r
-}\r
-\r
-/**\r
-  Sync memory page attributes for AP.\r
-\r
-  @param[in] Procedure            A pointer to the function to be run on enabled APs of\r
-                                  the system.\r
-**/\r
-VOID\r
-SyncMemoryPageAttributesAp (\r
-  IN EFI_AP_PROCEDURE            Procedure\r
-  )\r
-{\r
-  EFI_STATUS                Status;\r
-  EFI_MP_SERVICES_PROTOCOL  *MpService;\r
-\r
-  Status = gBS->LocateProtocol (\r
-                  &gEfiMpServiceProtocolGuid,\r
-                  NULL,\r
-                  (VOID **)&MpService\r
-                  );\r
-  //\r
-  // Synchronize the update with all APs\r
-  //\r
-  if (!EFI_ERROR (Status)) {\r
-    Status = MpService->StartupAllAPs (\r
-                          MpService,          // This\r
-                          Procedure,          // Procedure\r
-                          FALSE,              // SingleThread\r
-                          NULL,               // WaitEvent\r
-                          0,                  // TimeoutInMicrosecsond\r
-                          NULL,               // ProcedureArgument\r
-                          NULL                // FailedCpuList\r
-                          );\r
-    ASSERT (Status == EFI_SUCCESS || Status == EFI_NOT_STARTED || Status == EFI_NOT_READY);\r
-  }\r
-}\r
-\r
 /**\r
   Return current paging context.\r
 \r
@@ -574,20 +510,6 @@ IsReadOnlyPageWriteProtected (
   return ((AsmReadCr0 () & BIT16) != 0);\r
 }\r
 \r
-/**\r
-  Disable write protection function for AP.\r
-\r
-  @param[in,out] Buffer  The pointer to private data buffer.\r
-**/\r
-VOID\r
-EFIAPI\r
-SyncCpuDisableWriteProtection (\r
-  IN OUT VOID *Buffer\r
-  )\r
-{\r
-  AsmWriteCr0 (AsmReadCr0() & ~BIT16);\r
-}\r
-\r
 /**\r
  Disable Write Protect on pages marked as read-only.\r
 **/\r
@@ -835,10 +757,13 @@ AssignMemoryPageAttributes (
   if (!EFI_ERROR(Status)) {\r
     if ((PagingContext == NULL) && IsModified) {\r
       //\r
-      // Flush TLB as last step\r
+      // Flush TLB as last step.\r
+      //\r
+      // Note: Since APs will always init CR3 register in HLT loop mode or do\r
+      // TLB flush in MWAIT loop mode, there's no need to flush TLB for them\r
+      // here.\r
       //\r
       CpuFlushTlb();\r
-      SyncMemoryPageAttributesAp (SyncCpuFlushTlb);\r
     }\r
   }\r
 \r