101 lines
2.4 KiB
C
101 lines
2.4 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
|
|
#ifndef __ASM_PREEMPT_H
|
|
#define __ASM_PREEMPT_H
|
|
|
|
#include <linux/thread_info.h>
|
|
|
|
#define PREEMPT_ENABLED (0)
|
|
|
|
static __always_inline int preempt_count(void)
|
|
{
|
|
return READ_ONCE(current_thread_info()->preempt_count);
|
|
}
|
|
|
|
static __always_inline volatile int *preempt_count_ptr(void)
|
|
{
|
|
return ¤t_thread_info()->preempt_count;
|
|
}
|
|
|
|
static __always_inline void preempt_count_set(int pc)
|
|
{
|
|
*preempt_count_ptr() = pc;
|
|
}
|
|
|
|
/*
|
|
* must be macros to avoid header recursion hell
|
|
*/
|
|
#define init_task_preempt_count(p) do { \
|
|
task_thread_info(p)->preempt_count = FORK_PREEMPT_COUNT; \
|
|
} while (0)
|
|
|
|
#define init_idle_preempt_count(p, cpu) do { \
|
|
task_thread_info(p)->preempt_count = PREEMPT_DISABLED; \
|
|
} while (0)
|
|
|
|
static __always_inline void set_preempt_need_resched(void)
|
|
{
|
|
}
|
|
|
|
static __always_inline void clear_preempt_need_resched(void)
|
|
{
|
|
}
|
|
|
|
static __always_inline bool test_preempt_need_resched(void)
|
|
{
|
|
return false;
|
|
}
|
|
|
|
/*
|
|
* The various preempt_count add/sub methods
|
|
*/
|
|
|
|
static __always_inline void __preempt_count_add(int val)
|
|
{
|
|
*preempt_count_ptr() += val;
|
|
}
|
|
|
|
static __always_inline void __preempt_count_sub(int val)
|
|
{
|
|
*preempt_count_ptr() -= val;
|
|
}
|
|
|
|
static __always_inline bool __preempt_count_dec_and_test(void)
|
|
{
|
|
/*
|
|
* Because of load-store architectures cannot do per-cpu atomic
|
|
* operations; we cannot use PREEMPT_NEED_RESCHED because it might get
|
|
* lost.
|
|
*/
|
|
return !--*preempt_count_ptr() && tif_need_resched();
|
|
}
|
|
|
|
/*
|
|
* Returns true when we need to resched and can (barring IRQ state).
|
|
*/
|
|
static __always_inline bool should_resched(int preempt_offset)
|
|
{
|
|
return unlikely(preempt_count() == preempt_offset &&
|
|
tif_need_resched());
|
|
}
|
|
|
|
#ifdef CONFIG_PREEMPTION
|
|
extern asmlinkage void preempt_schedule(void);
|
|
extern asmlinkage void preempt_schedule_notrace(void);
|
|
|
|
#if defined(CONFIG_PREEMPT_DYNAMIC) && defined(CONFIG_HAVE_PREEMPT_DYNAMIC_KEY)
|
|
|
|
void dynamic_preempt_schedule(void);
|
|
void dynamic_preempt_schedule_notrace(void);
|
|
#define __preempt_schedule() dynamic_preempt_schedule()
|
|
#define __preempt_schedule_notrace() dynamic_preempt_schedule_notrace()
|
|
|
|
#else /* !CONFIG_PREEMPT_DYNAMIC || !CONFIG_HAVE_PREEMPT_DYNAMIC_KEY*/
|
|
|
|
#define __preempt_schedule() preempt_schedule()
|
|
#define __preempt_schedule_notrace() preempt_schedule_notrace()
|
|
|
|
#endif /* CONFIG_PREEMPT_DYNAMIC && CONFIG_HAVE_PREEMPT_DYNAMIC_KEY*/
|
|
#endif /* CONFIG_PREEMPTION */
|
|
|
|
#endif /* __ASM_PREEMPT_H */
|