[edk2-devel] [edk2-platforms V2 3/3] MinPlatformPkg: Sort ApicIdOrderTable by special rules

["duntan" <dun.tan@intel.com>]

Sort ApicIdOrderTable by following special rules:
1. Make sure BSP is the first entry.
2. For APs, big core first, then small core.

With this implementation, BIOS can present cores in order
of relative performance in MADT. Linux OS would schedule
cores by the order that they are presented in the MADT
LocalX2ApicStruct entries.Then Linux OS would think of
this as relative performance order. This implementation
can benefit the linux os usage case.

Signed-off-by: Dun Tan <dun.tan@intel.com>
Cc: Ray Ni <ray.ni@intel.com>
Cc: Jason Lou <yun.lou@intel.com>
Cc: Chasel Chiu <chasel.chiu@intel.com>
Cc: Nate DeSimone <nathaniel.l.desimone@intel.com>
Cc: Liming Gao <gaoliming@byosoft.com.cn>
Cc: Eric Dong <eric.dong@intel.com>
---
 Platform/Intel/MinPlatformPkg/Acpi/AcpiTables/AcpiPlatform.c | 63 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 63 insertions(+)

diff --git a/Platform/Intel/MinPlatformPkg/Acpi/AcpiTables/AcpiPlatform.c b/Platform/Intel/MinPlatformPkg/Acpi/AcpiTables/AcpiPlatform.c
index 1fa70e3df9..389df48824 100644
--- a/Platform/Intel/MinPlatformPkg/Acpi/AcpiTables/AcpiPlatform.c
+++ b/Platform/Intel/MinPlatformPkg/Acpi/AcpiTables/AcpiPlatform.c
@@ -132,6 +132,62 @@ AppendCpuMapTableEntry (
 
 }
 
+/**
+  Sort CpuApicIdOrderTable based on the following rules:
+  1.Make sure BSP is the first entry.
+  2.Big core first, then small core.
+
+  @param[in] CpuApicIdOrderTable      Pointer to EFI_CPU_ID_ORDER_MAP
+  @param[in] Count                    Number to EFI_CPU_ID_ORDER_MAP
+  @param[in] BspIndex                 BSP index
+**/
+VOID
+SortApicIdOrderTable (
+  IN  EFI_CPU_ID_ORDER_MAP  *CpuApicIdOrderTable,
+  IN  UINTN                 Count,
+  IN  UINTN                 BspIndex
+  )
+{
+  UINTN                 Index;
+  UINTN                 SubIndex;
+  EFI_CPU_ID_ORDER_MAP  SortBuffer;
+
+  //
+  // Put BSP at the first entry.
+  //
+  if (BspIndex != 0) {
+    CopyMem (&SortBuffer, &CpuApicIdOrderTable[BspIndex], sizeof (EFI_CPU_ID_ORDER_MAP));
+    CopyMem (&CpuApicIdOrderTable[1], CpuApicIdOrderTable, (BspIndex) * sizeof (EFI_CPU_ID_ORDER_MAP));
+    CopyMem (CpuApicIdOrderTable, &SortBuffer, sizeof (EFI_CPU_ID_ORDER_MAP));
+  }
+
+  //
+  // If there are more than 2 cores, perform insertion sort for rest cores except the bsp in first entry
+  // to move big cores in front of small cores.
+  // Also the original order based on the MpService index inside big cores and small cores are retained.
+  //
+  for (Index = 2; Index < Count; Index++) {
+    if (CpuApicIdOrderTable[Index].CoreType == CPUID_CORE_TYPE_INTEL_ATOM) {
+      continue;
+    }
+
+    CopyMem (&SortBuffer, &CpuApicIdOrderTable[Index], sizeof (EFI_CPU_ID_ORDER_MAP));
+
+    for (SubIndex = Index - 1; SubIndex >= 1; SubIndex--) {
+      if (CpuApicIdOrderTable[SubIndex].CoreType == CPUID_CORE_TYPE_INTEL_ATOM) {
+        CopyMem (&CpuApicIdOrderTable[SubIndex + 1], &CpuApicIdOrderTable[SubIndex], sizeof (EFI_CPU_ID_ORDER_MAP));
+      } else {
+        //
+        // Except the BSP, all cores in front of SubIndex must be big cores.
+        //
+        break;
+      }
+    }
+
+    CopyMem (&CpuApicIdOrderTable[SubIndex + 1], &SortBuffer, sizeof (EFI_CPU_ID_ORDER_MAP));
+  }
+}
+
 /**
   Get CPU core type.
 
@@ -174,6 +230,7 @@ CreateCpuLocalApicInTable (
   EFI_CPU_ID_ORDER_MAP                      *CpuIdMapPtr;
   UINT32                                    Socket;
   UINT32                                    CpuidMaxInput;
+  UINTN                                     BspIndex;
 
   Status = EFI_SUCCESS;
 
@@ -198,6 +255,10 @@ CreateCpuLocalApicInTable (
                            &ProcessorInfoBuffer
                            );
 
+    if ((ProcessorInfoBuffer.StatusFlag & PROCESSOR_AS_BSP_BIT) != 0) {
+      BspIndex = Index;
+    }
+
     CpuIdMapPtr = (EFI_CPU_ID_ORDER_MAP *) &CpuApicIdOrderTable[Index];
     if ((ProcessorInfoBuffer.StatusFlag & PROCESSOR_ENABLED_BIT) != 0) {
       CpuIdMapPtr->ApicId  = (UINT32)ProcessorInfoBuffer.ProcessorId;
@@ -230,6 +291,8 @@ CreateCpuLocalApicInTable (
     }
   }
 
+  SortApicIdOrderTable (CpuApicIdOrderTable, mNumberOfCpus, BspIndex);
+
   DEBUG ((DEBUG_INFO, "::ACPI::  APIC ID Order Table Init.   mNumOfBitShift = %x\n", mNumOfBitShift));
   DebugDisplayReOrderTable (CpuApicIdOrderTable);
 
-- 
2.31.1.windows.1



-=-=-=-=-=-=-=-=-=-=-=-
Groups.io Links: You receive all messages sent to this group.
View/Reply Online (#117281): https://edk2.groups.io/g/devel/message/117281
Mute This Topic: https://groups.io/mt/105259125/7686176
Group Owner: devel+owner@edk2.groups.io
Unsubscribe: https://edk2.groups.io/g/devel/unsub [rebecca@openfw.io]
-=-=-=-=-=-=-=-=-=-=-=-