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Diffstat (limited to 'arch/loongarch/include/asm/switch_to.h')
| -rw-r--r-- | arch/loongarch/include/asm/switch_to.h | 41 |
1 files changed, 41 insertions, 0 deletions
diff --git a/arch/loongarch/include/asm/switch_to.h b/arch/loongarch/include/asm/switch_to.h new file mode 100644 index 000000000..43a5ab162 --- /dev/null +++ b/arch/loongarch/include/asm/switch_to.h @@ -0,0 +1,41 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (C) 2020-2022 Loongson Technology Corporation Limited + */ +#ifndef _ASM_SWITCH_TO_H +#define _ASM_SWITCH_TO_H + +#include <asm/cpu-features.h> +#include <asm/fpu.h> + +struct task_struct; + +/** + * __switch_to - switch execution of a task + * @prev: The task previously executed. + * @next: The task to begin executing. + * @next_ti: task_thread_info(next). + * @sched_ra: __schedule return address. + * @sched_cfa: __schedule call frame address. + * + * This function is used whilst scheduling to save the context of prev & load + * the context of next. Returns prev. + */ +extern asmlinkage struct task_struct *__switch_to(struct task_struct *prev, + struct task_struct *next, struct thread_info *next_ti, + void *sched_ra, void *sched_cfa); + +/* + * For newly created kernel threads switch_to() will return to + * ret_from_kernel_thread, newly created user threads to ret_from_fork. + * That is, everything following __switch_to() will be skipped for new threads. + * So everything that matters to new threads should be placed before __switch_to(). + */ +#define switch_to(prev, next, last) \ +do { \ + lose_fpu_inatomic(1, prev); \ + (last) = __switch_to(prev, next, task_thread_info(next), \ + __builtin_return_address(0), __builtin_frame_address(0)); \ +} while (0) + +#endif /* _ASM_SWITCH_TO_H */ |