Kernel support for processor affinity.

Change-Id: Ie84a805bad58032085208a98b1b31393def681cb
Reviewed-on: http://gfwr801.rchland.ibm.com:8080/gerrit/100
Tested-by: Jenkins Server
Reviewed-by: Douglas R. Gilbert <dgilbert@us.ibm.com>
Reviewed-by: Andrew J. Geissler <andrewg@us.ibm.com>
Reviewed-by: Nicholas E. Bofferding <bofferdn@us.ibm.com>

3 files changed, 45 insertions, 4 deletions

diff --git a/src/include/kernel/cpu.H b/src/include/kernel/cpu.H
index 4d5134114..0fb794989 100644
--- a/src/include/kernel/cpu.H
+++ b/src/include/kernel/cpu.H
@@ -1,3 +1,8 @@
+/** @file cpu.H
+ *  @brief Defines kernel information and functions about CPUs.
+ *  
+ *  In this kernel the term CPU refers to a hardware thread (SMT), not core.
+ */
 #ifndef __KERNEL_CPU_H
 #define __KERNEL_CPU_H
 
@@ -10,17 +15,31 @@
 
 class Scheduler;
 
+/** @struct cpu_t
+ *  @brief Stores per-CPU kernel information.
+ */
 struct cpu_t
 {
+        /** Stack to use while in kernel mode. */
     void* kernel_stack;
+        /** ID of the CPU (PIR value) */
     cpuid_t cpu;
-
+        
+        /** Pointer to the scheduler for this CPU (may not be unique) */
     Scheduler* scheduler;
+        /** Location for scheduler to store per-CPU data, currently used
+         *  for the local run-queue for processor affinity.
+         */
+    void* scheduler_extra;
+        /** Pointer to the idle task for this CPU */
     task_t* idle_task;
 };
 
+/** @fn getCpuId
+ *  @brief Read the PIR value to determine the cpuid_t of this CPU.
+ */
 ALWAYS_INLINE
-inline uint64_t getCpuId()
+inline cpuid_t getCpuId()
 {
     return getPIR() & (KERNEL_MAX_SUPPORTED_CPUS - 1);
 }
diff --git a/src/include/kernel/scheduler.H b/src/include/kernel/scheduler.H
index 71b21559a..9cbf83d39 100644
--- a/src/include/kernel/scheduler.H
+++ b/src/include/kernel/scheduler.H
@@ -23,7 +23,8 @@ class Scheduler
 	~Scheduler() {};
 
     private:
-	Util::Locked::Queue<task_t, true, Spinlock> iv_taskList;
+        typedef Util::Locked::Queue<task_t, true, Spinlock> Runqueue_t;
+        Runqueue_t iv_taskList;
 };
 
 #endif
diff --git a/src/include/kernel/task.H b/src/include/kernel/task.H
index c27c7e8ce..6cd49028d 100644
--- a/src/include/kernel/task.H
+++ b/src/include/kernel/task.H
@@ -1,8 +1,16 @@
+/** @file task.H
+ *  @brief Defines kernel information about tasks.
+ */
 #ifndef __KERNEL_TASK_H
 #define __KERNEL_TASK_H
 
 #include <kernel/types.h>
 
+/** @struct context_t
+ *  @brief Defines the save-restore context for the task.
+ *
+ *  See PowerISA for information on registers listed.
+ */
 struct context_t
 {
     void* stack_ptr;
@@ -14,12 +22,25 @@ struct context_t
     uint64_t xer;
 };
 
+/** @struct task_t
+ *  @brief The kernel-level task structure.
+ */
 struct task_t
 {
+        /** Pointer to the CPU this task is assigned to. */
     cpu_t* cpu;
+        /** Context information.  This MUST stay here due to 
+         *  save-restore asm code. */
     context_t context;
-    
+        
+        /** Task ID */
     tid_t tid;
+        /** Determines if user-space would like this task pinned to a CPU.
+         *  This value is considered a count of the number of times the pinned
+         *  as been requested, so pinning can be used recursively. */
+    uint64_t affinity_pinned;
+        
+        // Pointers for queue containers.
     task_t* prev;
     task_t* next;
 };