1/* SPDX-License-Identifier: GPL-2.0 */
 2/*
 3 * Copyright (C) 2020-2022 Loongson Technology Corporation Limited
 4 */
 5#ifndef _ASM_SWITCH_TO_H
 6#define _ASM_SWITCH_TO_H
 7
 8#include <asm/cpu-features.h>
 9#include <asm/fpu.h>
 
10
11struct task_struct;
12
13/**
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.
20 *
21 * This function is used whilst scheduling to save the context of prev & load
22 * the context of next. Returns prev.
23 */
24extern 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);
27
28/*
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().
33 */
34#define switch_to(prev, next, last)						\
35do {										\
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));	\
39} while (0)
40
41#endif /* _ASM_SWITCH_TO_H */

 1/* SPDX-License-Identifier: GPL-2.0 */
 2/*
 3 * Copyright (C) 2020-2022 Loongson Technology Corporation Limited
 4 */
 5#ifndef _ASM_SWITCH_TO_H
 6#define _ASM_SWITCH_TO_H
 7
 8#include <asm/cpu-features.h>
 9#include <asm/fpu.h>
10#include <asm/lbt.h>
11
12struct task_struct;
13
14/**
15 * __switch_to - switch execution of a task
16 * @prev:	The task previously executed.
17 * @next:	The task to begin executing.
18 * @next_ti:	task_thread_info(next).
19 * @sched_ra:	__schedule return address.
20 * @sched_cfa:	__schedule call frame address.
21 *
22 * This function is used whilst scheduling to save the context of prev & load
23 * the context of next. Returns prev.
24 */
25extern asmlinkage struct task_struct *__switch_to(struct task_struct *prev,
26			struct task_struct *next, struct thread_info *next_ti,
27			void *sched_ra, void *sched_cfa);
28
29/*
30 * For newly created kernel threads switch_to() will return to
31 * ret_from_kernel_thread, newly created user threads to ret_from_fork.
32 * That is, everything following __switch_to() will be skipped for new threads.
33 * So everything that matters to new threads should be placed before __switch_to().
34 */
35#define switch_to(prev, next, last)						\
36do {										\
37	lose_fpu_inatomic(1, prev);						\
38	lose_lbt_inatomic(1, prev);						\
39	hw_breakpoint_thread_switch(next);					\
40	(last) = __switch_to(prev, next, task_thread_info(next),		\
41		 __builtin_return_address(0), __builtin_frame_address(0));	\
42} while (0)
43
44#endif /* _ASM_SWITCH_TO_H */