[PATCH 2/4] x86: arch specific task_struct allocator

[Akinobu Mita <akinobu.mita@gmail.com>]

This patch defines x86 specific task_struct allocator.
It is just duplication of generic task-struct allocator for now.
Forthcoming patch will make actual change to it.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
---
 arch/x86/include/asm/thread_info.h |    6 ++++++
 arch/x86/kernel/process.c          |   16 ++++++++++++++++
 2 files changed, 22 insertions(+)

Index: 2.6/arch/x86/kernel/process.c
===================================================================
--- 2.6.orig/arch/x86/kernel/process.c
+++ 2.6/arch/x86/kernel/process.c
@@ -44,8 +44,24 @@ void free_thread_info(struct thread_info
 	free_pages((unsigned long)ti, get_order(THREAD_SIZE));
 }
 
+static struct kmem_cache *task_struct_cachep;
+
+struct task_struct *alloc_task_struct(void)
+{
+	return kmem_cache_alloc(task_struct_cachep, GFP_KERNEL);
+}
+
+void free_task_struct(struct task_struct *tsk)
+{
+	kmem_cache_free(task_struct_cachep, tsk);
+}
+
 void arch_task_cache_init(void)
 {
+	task_struct_cachep = kmem_cache_create("task_struct",
+				sizeof(struct task_struct), ARCH_MIN_TASKALIGN,
+				SLAB_PANIC, NULL);
+
         task_xstate_cachep =
         	kmem_cache_create("task_xstate", xstate_size,
 				  __alignof__(union thread_xstate),
Index: 2.6/arch/x86/include/asm/thread_info.h
===================================================================
--- 2.6.orig/arch/x86/include/asm/thread_info.h
+++ 2.6/arch/x86/include/asm/thread_info.h
@@ -260,5 +260,11 @@ extern void arch_task_cache_init(void);
 extern void free_thread_info(struct thread_info *ti);
 extern int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src);
 #define arch_task_cache_init arch_task_cache_init
+
+#define __HAVE_ARCH_TASK_STRUCT_ALLOCATOR
+
+extern struct task_struct *alloc_task_struct(void);
+extern void free_task_struct(struct task_struct *tsk);
+
 #endif
 #endif /* _ASM_X86_THREAD_INFO_H */