diff options
Diffstat (limited to 'arch/riscv/include/asm/switch_to.h')
| -rw-r--r-- | arch/riscv/include/asm/switch_to.h | 69 |
1 files changed, 69 insertions, 0 deletions
diff --git a/arch/riscv/include/asm/switch_to.h b/arch/riscv/include/asm/switch_to.h new file mode 100644 index 000000000000..dd6b05bff75b --- /dev/null +++ b/arch/riscv/include/asm/switch_to.h @@ -0,0 +1,69 @@ +/* + * Copyright (C) 2012 Regents of the University of California + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation, version 2. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#ifndef _ASM_RISCV_SWITCH_TO_H +#define _ASM_RISCV_SWITCH_TO_H + +#include <asm/processor.h> +#include <asm/ptrace.h> +#include <asm/csr.h> + +extern void __fstate_save(struct task_struct *save_to); +extern void __fstate_restore(struct task_struct *restore_from); + +static inline void __fstate_clean(struct pt_regs *regs) +{ + regs->sstatus |= (regs->sstatus & ~(SR_FS)) | SR_FS_CLEAN; +} + +static inline void fstate_save(struct task_struct *task, + struct pt_regs *regs) +{ + if ((regs->sstatus & SR_FS) == SR_FS_DIRTY) { + __fstate_save(task); + __fstate_clean(regs); + } +} + +static inline void fstate_restore(struct task_struct *task, + struct pt_regs *regs) +{ + if ((regs->sstatus & SR_FS) != SR_FS_OFF) { + __fstate_restore(task); + __fstate_clean(regs); + } +} + +static inline void __switch_to_aux(struct task_struct *prev, + struct task_struct *next) +{ + struct pt_regs *regs; + + regs = task_pt_regs(prev); + if (unlikely(regs->sstatus & SR_SD)) + fstate_save(prev, regs); + fstate_restore(next, task_pt_regs(next)); +} + +extern struct task_struct *__switch_to(struct task_struct *, + struct task_struct *); + +#define switch_to(prev, next, last) \ +do { \ + struct task_struct *__prev = (prev); \ + struct task_struct *__next = (next); \ + __switch_to_aux(__prev, __next); \ + ((last) = __switch_to(__prev, __next)); \ +} while (0) + +#endif /* _ASM_RISCV_SWITCH_TO_H */ |