1/* SPDX-License-Identifier: GPL-2.0 */
 2#ifndef __ASM_ARM_SWITCH_TO_H
 3#define __ASM_ARM_SWITCH_TO_H
 4
 5#include <linux/thread_info.h>
 
 6
 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_PREEMPTION) && defined(CONFIG_SMP) && defined(CONFIG_CPU_V7)
14#define __complete_pending_tlbi()	dsb(ish)
15#else
16#define __complete_pending_tlbi()
17#endif
18
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 */
24extern struct task_struct *__switch_to(struct task_struct *, struct thread_info *, struct thread_info *);
25
26#define switch_to(prev,next,last)					\
27do {									\
28	__complete_pending_tlbi();					\
 
 
29	last = __switch_to(prev,task_thread_info(prev), task_thread_info(next));	\
30} while (0)
31
32#endif /* __ASM_ARM_SWITCH_TO_H */

 1/* SPDX-License-Identifier: GPL-2.0 */
 2#ifndef __ASM_ARM_SWITCH_TO_H
 3#define __ASM_ARM_SWITCH_TO_H
 4
 5#include <linux/thread_info.h>
 6#include <asm/smp_plat.h>
 7
 8/*
 9 * For v7 SMP cores running a preemptible kernel we may be pre-empted
10 * during a TLB maintenance operation, so execute an inner-shareable dsb
11 * to ensure that the maintenance completes in case we migrate to another
12 * CPU.
13 */
14#if defined(CONFIG_PREEMPTION) && defined(CONFIG_SMP) && defined(CONFIG_CPU_V7)
15#define __complete_pending_tlbi()	dsb(ish)
16#else
17#define __complete_pending_tlbi()
18#endif
19
20/*
21 * switch_to(prev, next) should switch from task `prev' to `next'
22 * `prev' will never be the same as `next'.  schedule() itself
23 * contains the memory barrier to tell GCC not to cache `current'.
24 */
25extern struct task_struct *__switch_to(struct task_struct *, struct thread_info *, struct thread_info *);
26
27#define switch_to(prev,next,last)					\
28do {									\
29	__complete_pending_tlbi();					\
30	if (IS_ENABLED(CONFIG_CURRENT_POINTER_IN_TPIDRURO) || is_smp())	\
31		__this_cpu_write(__entry_task, next);			\
32	last = __switch_to(prev,task_thread_info(prev), task_thread_info(next));	\
33} while (0)
34
35#endif /* __ASM_ARM_SWITCH_TO_H */