88 lines · 1.9 KB · C
RawDownload
/* 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 &current_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_ENABLED; \} 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_PREEMPTIONextern asmlinkage void preempt_schedule(void);#define __preempt_schedule() preempt_schedule()extern asmlinkage void preempt_schedule_notrace(void);#define __preempt_schedule_notrace() preempt_schedule_notrace()#endif /* CONFIG_PREEMPTION */ #endif /* __ASM_PREEMPT_H */