UefiCpuPkg/MtrrLib: Add notes for usage by BSP/APs

Except for MtrrSetAllMtrrs(), others services are not suggested to be invoked by
APs because they are not necessary and may invoke DEBUG() to dump MTRR setting.

Cc: Feng Tian <feng.tian@intel.com>
Cc: Michael Kinney <michael.d.kinney@intel.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Jeff Fan <jeff.fan@intel.com>
Reviewed: Laszlo Ersek <lersek@redhat.com>

diff --git a/UefiCpuPkg/Library/MtrrLib/MtrrLib.c b/UefiCpuPkg/Library/MtrrLib/MtrrLib.c
index f667a8f79690e98a4058298f75998094be201dc9..5aef7724e29d55c4f3656277763818252ac1fcc2 100644 (file)
--- a/UefiCpuPkg/Library/MtrrLib/MtrrLib.c
+++ b/UefiCpuPkg/Library/MtrrLib/MtrrLib.c
@@ -1,6 +1,10 @@
 /** @file\r
   MTRR setting library\r
 \r
+  @par Note: \r
+    Most of services in this library instance are suggested to be invoked by BSP only,\r
+    except for MtrrSetAllMtrrs() which is used to sync BSP's MTRR setting to APs.\r
+\r
   Copyright (c) 2008 - 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