[PATCH v3 2/2] UefiCpuPkg/MpInitLib: Avoid ApInitReconfig in PEI.

["Dong, Eric" <eric.dong@intel.com>]

From: "Dong, Eric" <eric.dong@intel.com>

REF: https://bugzilla.tianocore.org/show_bug.cgi?id=2683

In PEI phase, AP already been waked up through ApInitConfig,
so it can directly wake up it through change wakup buffer
instead of use ApInitReconfig flag. It can save some time.

Change code to only use ApInitReconfig flag in DXE phase
which must need to update the wake up buffer.

Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Chandana Kumar <chandana.c.kumar@intel.com>
Signed-off-by: Eric Dong <eric.dong@intel.com>
Reviewed-by: Ray Ni <ray.ni@intel.com>
---
 UefiCpuPkg/Library/MpInitLib/MpLib.c | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/UefiCpuPkg/Library/MpInitLib/MpLib.c b/UefiCpuPkg/Library/MpInitLib/MpLib.c
index 7fd757b428..64528fd1e7 100644
--- a/UefiCpuPkg/Library/MpInitLib/MpLib.c
+++ b/UefiCpuPkg/Library/MpInitLib/MpLib.c
@@ -1820,7 +1820,14 @@ MpInitLibInitialize (
   // Wakeup APs to do some AP initialize sync (Microcode & MTRR)
   //
   if (CpuMpData->CpuCount > 1) {
-    CpuMpData->InitFlag = ApInitReconfig;
+    if (OldCpuMpData != NULL) {
+      //
+      // Only needs to use this flag for DXE phase to update the wake up
+      // buffer. Wakeup buffer allocated in PEI phase is no longer valid
+      // in DXE.
+      //
+      CpuMpData->InitFlag = ApInitReconfig;
+    }
     WakeUpAP (CpuMpData, TRUE, 0, ApInitializeSync, CpuMpData, TRUE);
     //
     // Wait for all APs finished initialization
@@ -1828,7 +1835,9 @@ MpInitLibInitialize (
     while (CpuMpData->FinishedCount < (CpuMpData->CpuCount - 1)) {
       CpuPause ();
     }
-    CpuMpData->InitFlag = ApInitDone;
+    if (OldCpuMpData != NULL) {
+      CpuMpData->InitFlag = ApInitDone;
+    }
     for (Index = 0; Index < CpuMpData->CpuCount; Index++) {
       SetApState (&CpuMpData->CpuData[Index], CpuStateIdle);
     }
-- 
2.23.0.windows.1