arch/riscv/kernel/kernel_mode_fpu.c

Source file repositories/reference/linux-study-clean/arch/riscv/kernel/kernel_mode_fpu.c

File Facts

System
Linux kernel
Corpus path
arch/riscv/kernel/kernel_mode_fpu.c
Extension
.c
Size
560 bytes
Lines
29
Domain
Architecture Layer
Bucket
arch/riscv
Inferred role
Architecture Layer: exported/initcall integration point
Status
integration implementation candidate

Why This File Exists

CPU and platform-specific kernel glue: boot entry, traps, syscall entry, interrupts, page tables, context switch, and low-level barriers.

Dependency Surface

Detected Declarations

Annotated Snippet

// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (C) 2023 SiFive
 */

#include <linux/export.h>
#include <linux/preempt.h>

#include <asm/csr.h>
#include <asm/fpu.h>
#include <asm/processor.h>
#include <asm/switch_to.h>

void kernel_fpu_begin(void)
{
	preempt_disable();
	fstate_save(current, task_pt_regs(current));
	csr_set(CSR_SSTATUS, SR_FS);
}
EXPORT_SYMBOL_GPL(kernel_fpu_begin);

void kernel_fpu_end(void)
{
	csr_clear(CSR_SSTATUS, SR_FS);
	fstate_restore(current, task_pt_regs(current));
	preempt_enable();
}
EXPORT_SYMBOL_GPL(kernel_fpu_end);

Annotation

Implementation Notes