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_PREEMPT) && 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 */
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 { \
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 */