linux-zen-desktop/arch/loongarch/kernel/kfpu.c

44 lines
778 B
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (C) 2023 Loongson Technology Corporation Limited
*/
#include <linux/cpu.h>
#include <linux/init.h>
#include <asm/fpu.h>
#include <asm/smp.h>
static DEFINE_PER_CPU(bool, in_kernel_fpu);
void kernel_fpu_begin(void)
{
preempt_disable();
WARN_ON(this_cpu_read(in_kernel_fpu));
this_cpu_write(in_kernel_fpu, true);
if (!is_fpu_owner())
enable_fpu();
else
_save_fp(&current->thread.fpu);
write_fcsr(LOONGARCH_FCSR0, 0);
}
EXPORT_SYMBOL_GPL(kernel_fpu_begin);
void kernel_fpu_end(void)
{
WARN_ON(!this_cpu_read(in_kernel_fpu));
if (!is_fpu_owner())
disable_fpu();
else
_restore_fp(&current->thread.fpu);
this_cpu_write(in_kernel_fpu, false);
preempt_enable();
}
EXPORT_SYMBOL_GPL(kernel_fpu_end);