linux_dsm_epyc7002/arch/riscv/include/asm/switch_to.h
Vincent Chen 69703eb9a8 riscv: Make __fstate_clean() work correctly.
Make the __fstate_clean() function correctly set the
state of sstatus.FS in pt_regs to SR_FS_CLEAN.

Fixes: 7db91e57a0 ("RISC-V: Task implementation")
Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: Vincent Chen <vincent.chen@sifive.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
[paul.walmsley@sifive.com: expanded "Fixes" commit ID]
Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
2019-08-14 13:20:46 -07:00

78 lines
1.8 KiB
C

/* SPDX-License-Identifier: GPL-2.0-only */
/*
* Copyright (C) 2012 Regents of the University of California
*/
#ifndef _ASM_RISCV_SWITCH_TO_H
#define _ASM_RISCV_SWITCH_TO_H
#include <asm/processor.h>
#include <asm/ptrace.h>
#include <asm/csr.h>
#ifdef CONFIG_FPU
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_off(struct task_struct *task,
struct pt_regs *regs)
{
regs->sstatus = (regs->sstatus & ~SR_FS) | SR_FS_OFF;
}
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 bool has_fpu;
#else
#define has_fpu false
#define fstate_save(task, regs) do { } while (0)
#define fstate_restore(task, regs) do { } while (0)
#define __switch_to_aux(__prev, __next) do { } while (0)
#endif
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); \
if (has_fpu) \
__switch_to_aux(__prev, __next); \
((last) = __switch_to(__prev, __next)); \
} while (0)
#endif /* _ASM_RISCV_SWITCH_TO_H */