112 lines
		
	
	
		
			2.4 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			112 lines
		
	
	
		
			2.4 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /* SPDX-License-Identifier: GPL-2.0 */
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| #ifndef _LINUX_SCHED_IDLE_H
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| #define _LINUX_SCHED_IDLE_H
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| 
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| #include <linux/sched.h>
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| 
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| enum cpu_idle_type {
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| 	__CPU_NOT_IDLE = 0,
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| 	CPU_IDLE,
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| 	CPU_NEWLY_IDLE,
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| 	CPU_MAX_IDLE_TYPES
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| };
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| 
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| #ifdef CONFIG_SMP
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| extern void wake_up_if_idle(int cpu);
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| #else
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| static inline void wake_up_if_idle(int cpu) { }
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| #endif
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| 
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| /*
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|  * Idle thread specific functions to determine the need_resched
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|  * polling state.
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|  */
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| #ifdef TIF_POLLING_NRFLAG
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| 
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| #ifdef _ASM_GENERIC_BITOPS_INSTRUMENTED_ATOMIC_H
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| 
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| static __always_inline void __current_set_polling(void)
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| {
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| 	arch_set_bit(TIF_POLLING_NRFLAG,
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| 		     (unsigned long *)(¤t_thread_info()->flags));
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| }
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| 
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| static __always_inline void __current_clr_polling(void)
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| {
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| 	arch_clear_bit(TIF_POLLING_NRFLAG,
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| 		       (unsigned long *)(¤t_thread_info()->flags));
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| }
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| 
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| #else
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| 
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| static __always_inline void __current_set_polling(void)
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| {
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| 	set_bit(TIF_POLLING_NRFLAG,
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| 		(unsigned long *)(¤t_thread_info()->flags));
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| }
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| 
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| static __always_inline void __current_clr_polling(void)
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| {
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| 	clear_bit(TIF_POLLING_NRFLAG,
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| 		  (unsigned long *)(¤t_thread_info()->flags));
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| }
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| 
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| #endif /* _ASM_GENERIC_BITOPS_INSTRUMENTED_ATOMIC_H */
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| 
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| static __always_inline bool __must_check current_set_polling_and_test(void)
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| {
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| 	__current_set_polling();
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| 
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| 	/*
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| 	 * Polling state must be visible before we test NEED_RESCHED,
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| 	 * paired by resched_curr()
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| 	 */
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| 	smp_mb__after_atomic();
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| 
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| 	return unlikely(tif_need_resched());
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| }
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| 
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| static __always_inline bool __must_check current_clr_polling_and_test(void)
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| {
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| 	__current_clr_polling();
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| 
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| 	/*
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| 	 * Polling state must be visible before we test NEED_RESCHED,
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| 	 * paired by resched_curr()
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| 	 */
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| 	smp_mb__after_atomic();
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| 
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| 	return unlikely(tif_need_resched());
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| }
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| 
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| #else
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| static inline void __current_set_polling(void) { }
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| static inline void __current_clr_polling(void) { }
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| 
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| static inline bool __must_check current_set_polling_and_test(void)
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| {
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| 	return unlikely(tif_need_resched());
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| }
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| static inline bool __must_check current_clr_polling_and_test(void)
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| {
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| 	return unlikely(tif_need_resched());
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| }
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| #endif
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| 
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| static __always_inline void current_clr_polling(void)
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| {
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| 	__current_clr_polling();
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| 
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| 	/*
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| 	 * Ensure we check TIF_NEED_RESCHED after we clear the polling bit.
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| 	 * Once the bit is cleared, we'll get IPIs with every new
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| 	 * TIF_NEED_RESCHED and the IPI handler, scheduler_ipi(), will also
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| 	 * fold.
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| 	 */
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| 	smp_mb(); /* paired with resched_curr() */
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| 
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| 	preempt_fold_need_resched();
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| }
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| 
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| #endif /* _LINUX_SCHED_IDLE_H */
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