[mirror_ubuntu-bionic-kernel.git] / arch / arm / include / asm / switch_to.h

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef __ASM_ARM_SWITCH_TO_H
#define __ASM_ARM_SWITCH_TO_H

#include <linux/thread_info.h>

/*
 * For v7 SMP cores running a preemptible kernel we may be pre-empted
 * during a TLB maintenance operation, so execute an inner-shareable dsb
 * to ensure that the maintenance completes in case we migrate to another
 * CPU.
 */
#if defined(CONFIG_PREEMPT) && defined(CONFIG_SMP) && defined(CONFIG_CPU_V7)
#define __complete_pending_tlbi()	dsb(ish)
#else
#define __complete_pending_tlbi()
#endif

/*
 * switch_to(prev, next) should switch from task `prev' to `next'
 * `prev' will never be the same as `next'.  schedule() itself
 * contains the memory barrier to tell GCC not to cache `current'.
 */
extern struct task_struct *__switch_to(struct task_struct *, struct thread_info *, struct thread_info *);

#define switch_to(prev,next,last)					\
do {									\
	__complete_pending_tlbi();					\
	last = __switch_to(prev,task_thread_info(prev), task_thread_info(next));	\
} while (0)

#endif /* __ASM_ARM_SWITCH_TO_H */
Commit	Line	Data
b2441318	1	/* SPDX-License-Identifier: GPL-2.0 */
9f97da78 DH	2	#ifndef __ASM_ARM_SWITCH_TO_H
	3	#define __ASM_ARM_SWITCH_TO_H
	4
	5	#include <linux/thread_info.h>
	6
73a6fdc4 WD	7	/*
	8	* For v7 SMP cores running a preemptible kernel we may be pre-empted
	9	* during a TLB maintenance operation, so execute an inner-shareable dsb
	10	* to ensure that the maintenance completes in case we migrate to another
	11	* CPU.
	12	*/
	13	#if defined(CONFIG_PREEMPT) && defined(CONFIG_SMP) && defined(CONFIG_CPU_V7)
7baa7aec WD	14	#define __complete_pending_tlbi() dsb(ish)
	15	#else
	16	#define __complete_pending_tlbi()
73a6fdc4 WD	17	#endif
73a6fdc4 WD	18
9f97da78 DH	19	/*
	20	* switch_to(prev, next) should switch from task `prev' to `next'
	21	* `prev' will never be the same as `next'. schedule() itself
	22	* contains the memory barrier to tell GCC not to cache `current'.
	23	*/
	24	extern struct task_struct __switch_to(struct task_struct , struct thread_info , struct thread_info );
	25
	26	#define switch_to(prev,next,last) \
	27	do { \
7baa7aec	28	__complete_pending_tlbi(); \
9f97da78 DH	29	last = __switch_to(prev,task_thread_info(prev), task_thread_info(next)); \
	30	} while (0)
	31
	32	#endif /* __ASM_ARM_SWITCH_TO_H */