sched/headers: Move task-stack related APIs from <linux/sched.h> to <linux/sched/task_stack.h>

Split out the task->stack related functionality, which is not really
part of the core scheduler APIs.

Only keep task_thread_info() because it's used by sched.h.

Update the code that uses those facilities.

Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

1 files changed, 9 insertions, 106 deletions

diff --git a/include/linux/sched.h b/include/linux/sched.h
index 3b3e31da416e..af9590c8bfb0 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -1450,6 +1450,15 @@ union thread_union {
 	unsigned long stack[THREAD_SIZE/sizeof(long)];
 };
 
+#ifdef CONFIG_THREAD_INFO_IN_TASK
+static inline struct thread_info *task_thread_info(struct task_struct *task)
+{
+	return &task->thread_info;
+}
+#elif !defined(__HAVE_THREAD_FUNCTIONS)
+# define task_thread_info(task)	((struct thread_info *)(task)->stack)
+#endif
+
 #ifndef __HAVE_ARCH_KSTACK_END
 static inline int kstack_end(void *addr)
 {
@@ -1540,112 +1549,6 @@ static inline void task_unlock(struct task_struct *p)
 	spin_unlock(&p->alloc_lock);
 }
 
-#ifdef CONFIG_THREAD_INFO_IN_TASK
-
-static inline struct thread_info *task_thread_info(struct task_struct *task)
-{
-	return &task->thread_info;
-}
-
-/*
- * When accessing the stack of a non-current task that might exit, use
- * try_get_task_stack() instead.  task_stack_page will return a pointer
- * that could get freed out from under you.
- */
-static inline void *task_stack_page(const struct task_struct *task)
-{
-	return task->stack;
-}
-
-#define setup_thread_stack(new,old)	do { } while(0)
-
-static inline unsigned long *end_of_stack(const struct task_struct *task)
-{
-	return task->stack;
-}
-
-#elif !defined(__HAVE_THREAD_FUNCTIONS)
-
-#define task_thread_info(task)	((struct thread_info *)(task)->stack)
-#define task_stack_page(task)	((void *)(task)->stack)
-
-static inline void setup_thread_stack(struct task_struct *p, struct task_struct *org)
-{
-	*task_thread_info(p) = *task_thread_info(org);
-	task_thread_info(p)->task = p;
-}
-
-/*
- * Return the address of the last usable long on the stack.
- *
- * When the stack grows down, this is just above the thread
- * info struct. Going any lower will corrupt the threadinfo.
- *
- * When the stack grows up, this is the highest address.
- * Beyond that position, we corrupt data on the next page.
- */
-static inline unsigned long *end_of_stack(struct task_struct *p)
-{
-#ifdef CONFIG_STACK_GROWSUP
-	return (unsigned long *)((unsigned long)task_thread_info(p) + THREAD_SIZE) - 1;
-#else
-	return (unsigned long *)(task_thread_info(p) + 1);
-#endif
-}
-
-#endif
-
-#ifdef CONFIG_THREAD_INFO_IN_TASK
-static inline void *try_get_task_stack(struct task_struct *tsk)
-{
-	return atomic_inc_not_zero(&tsk->stack_refcount) ?
-		task_stack_page(tsk) : NULL;
-}
-
-extern void put_task_stack(struct task_struct *tsk);
-#else
-static inline void *try_get_task_stack(struct task_struct *tsk)
-{
-	return task_stack_page(tsk);
-}
-
-static inline void put_task_stack(struct task_struct *tsk) {}
-#endif
-
-#define task_stack_end_corrupted(task) \
-		(*(end_of_stack(task)) != STACK_END_MAGIC)
-
-static inline int object_is_on_stack(void *obj)
-{
-	void *stack = task_stack_page(current);
-
-	return (obj >= stack) && (obj < (stack + THREAD_SIZE));
-}
-
-extern void thread_stack_cache_init(void);
-
-#ifdef CONFIG_DEBUG_STACK_USAGE
-static inline unsigned long stack_not_used(struct task_struct *p)
-{
-	unsigned long *n = end_of_stack(p);
-
-	do { 	/* Skip over canary */
-# ifdef CONFIG_STACK_GROWSUP
-		n--;
-# else
-		n++;
-# endif
-	} while (!*n);
-
-# ifdef CONFIG_STACK_GROWSUP
-	return (unsigned long)end_of_stack(p) - (unsigned long)n;
-# else
-	return (unsigned long)n - (unsigned long)end_of_stack(p);
-# endif
-}
-#endif
-extern void set_task_stack_end_magic(struct task_struct *tsk);
-
 /* set thread flags in other task's structures
  * - see asm/thread_info.h for TIF_xxxx flags available
  */