Commit f3ac6067 authored by Ingo Molnar's avatar Ingo Molnar
Browse files

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: default avatarLinus 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: default avatarIngo Molnar <mingo@kernel.org>
parent d04b0ad3
......@@ -11,7 +11,7 @@
#include <linux/delay.h>
#include <linux/io.h>
#include <linux/irqchip/mips-gic.h>
#include <linux/sched.h>
#include <linux/sched/task_stack.h>
#include <linux/sched/hotplug.h>
#include <linux/slab.h>
#include <linux/smp.h>
......
......@@ -21,7 +21,7 @@
#include <linux/interrupt.h>
#include <linux/smp.h>
#include <linux/kernel_stat.h>
#include <linux/sched.h>
#include <linux/sched/task_stack.h>
#include <asm/mmu_context.h>
#include <asm/io.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
*/
......
#ifndef _LINUX_SCHED_TASK_STACK_H
#define _LINUX_SCHED_TASK_STACK_H
/*
* task->stack (kernel stack) handling interfaces:
*/
#include <linux/sched.h>
#include <linux/magic.h>
#ifdef CONFIG_THREAD_INFO_IN_TASK
/*
* 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_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);
#endif /* _LINUX_SCHED_TASK_STACK_H */
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