Dedicated Idle process and thread initialization with dynamic affinity allocation

xtoskrnl/ke/kprocess.cc

@@ -9,6 +9,21 @@
 #include <xtos.hh>
 
 
+/**
+ * Retrieves the pointer to the global Idle process.
+ *
+ * @return Returns a pointer to the Idle process.
+ *
+ * @since XT 1.0
+ */
+XTAPI
+PKPROCESS
+KE::KProcess::GetIdleProcess(VOID)
+{
+    /* Return pointer to the idle process */
+    return &InitialProcess.ProcessControlBlock;
+}
+
 /**
  * Retrieves a pointer to the system's initial executive process object.
  *
@@ -23,6 +38,55 @@ KE::KProcess::GetInitialProcess(VOID)
     return &InitialProcess;
 }
 
+/**
+ * Initializes the system-wide Idle Process.
+ *
+ * @param Process
+ *        Supplies a pointer to the KPROCESS structure representing the idle process.
+ *
+ * @param DirectoryTable
+ *        Supplies a pointer to the initial hardware page directory table for the process.
+ *
+ * @return This routine does not return any value.
+ *
+ * @since XT 1.0
+ */
+XTAPI
+VOID
+KE::KProcess::InitializeIdleProcess(IN OUT PKPROCESS Process,
+                                    IN PULONG_PTR DirectoryTable)
+{
+    ULONG AffinitySize, MapSize;
+    PACPI_SYSTEM_INFO SysInfo;
+
+    /* Retrieve hardware topology from ACPI */
+    HL::Acpi::GetSystemInformation(&SysInfo);
+
+    /* Calculate the required size for KAFFINITY_MAP structures */
+    AffinitySize = (SysInfo->CpuCount + 63) / 64;
+    MapSize = sizeof(KAFFINITY_MAP) + (AffinitySize * sizeof(KAFFINITY));
+
+    /* Align size to the 8-byte boundary */
+    MapSize = (MapSize + 7) & ~7;
+
+    /* Allocate the process-level affinity structures */
+    MM::Allocator::AllocatePool(NonPagedPool, MapSize, (PVOID*)&Process->Affinity);
+    MM::Allocator::AllocatePool(NonPagedPool, MapSize, (PVOID*)&Process->ActiveProcessors);
+
+    /* Zero the process-level affinity structures */
+    RTL::Memory::ZeroMemory(Process->Affinity, MapSize);
+    RTL::Memory::ZeroMemory(Process->ActiveProcessors, MapSize);
+
+    /* Initialize size metadata */
+    Process->Affinity->Count = (USHORT)AffinitySize;
+    Process->Affinity->Size = (USHORT)AffinitySize;
+    Process->ActiveProcessors->Size = (USHORT)AffinitySize;
+
+    /* Initialize Idle process */
+    KE::KProcess::InitializeProcess(Process, 0, DirectoryTable, FALSE);
+    Process->Quantum = MAXCHAR;
+}
+
 /**
  * Initializes the process.
  *
@@ -49,7 +113,6 @@ XTAPI
 VOID
 KE::KProcess::InitializeProcess(IN OUT PKPROCESS Process,
                                 IN KPRIORITY Priority,
-                                IN KAFFINITY Affinity,
                                 IN PULONG_PTR DirectoryTable,
                                 IN BOOLEAN Alignment)
 {
@@ -68,11 +131,6 @@ KE::KProcess::InitializeProcess(IN OUT PKPROCESS Process,
     Process->BasePriority = Priority;
     Process->AutoAlignment = Alignment;
 
-    /* Initialize KAFFINITY_MAP for single-group affinity */
-    Process->Affinity.Count = 1;
-    Process->Affinity.Size = 1;
-    Process->Affinity.Bitmap[0] = Affinity;
-
     /* Set directory tables */
     Process->DirectoryTable[0] = DirectoryTable[0];
     Process->DirectoryTable[1] = DirectoryTable[1];