1 /* SPDX-License-Identifier: GPL-2.0 */
3 * Copyright (C) 2020-2022 Loongson Technology Corporation Limited
5 #ifndef _ASM_SWITCH_TO_H
6 #define _ASM_SWITCH_TO_H
8 #include <asm/cpu-features.h>
14 * __switch_to - switch execution of a task
15 * @prev: The task previously executed.
16 * @next: The task to begin executing.
17 * @next_ti: task_thread_info(next).
18 * @sched_ra: __schedule return address.
19 * @sched_cfa: __schedule call frame address.
21 * This function is used whilst scheduling to save the context of prev & load
22 * the context of next. Returns prev.
24 extern asmlinkage struct task_struct *__switch_to(struct task_struct *prev,
25 struct task_struct *next, struct thread_info *next_ti,
26 void *sched_ra, void *sched_cfa);
29 * For newly created kernel threads switch_to() will return to
30 * ret_from_kernel_thread, newly created user threads to ret_from_fork.
31 * That is, everything following __switch_to() will be skipped for new threads.
32 * So everything that matters to new threads should be placed before __switch_to().
34 #define switch_to(prev, next, last) \
36 lose_fpu_inatomic(1, prev); \
37 (last) = __switch_to(prev, next, task_thread_info(next), \
38 __builtin_return_address(0), __builtin_frame_address(0)); \
41 #endif /* _ASM_SWITCH_TO_H */