Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
os
linux
1/* SPDX-License-Identifier: GPL-2.0-only */
2/*
3 * Copyright (C) 2017 Linaro Ltd. <ard.biesheuvel@linaro.org>
4 */
5
6#ifndef __ASM_SIMD_H
7#define __ASM_SIMD_H
8
9#include <linux/compiler.h>
10#include <linux/irqflags.h>
11#include <linux/percpu.h>
12#include <linux/preempt.h>
13#include <linux/types.h>
14
15#ifdef CONFIG_KERNEL_MODE_NEON
16
17/*
18 * may_use_simd - whether it is allowable at this time to issue SIMD
19 * instructions or access the SIMD register file
20 *
21 * Callers must not assume that the result remains true beyond the next
22 * preempt_enable() or return from softirq context.
23 */
24static __must_check inline bool may_use_simd(void)
25{
26 /*
27 * We must make sure that the SVE has been initialized properly
28 * before using the SIMD in kernel.
29 */
30 return !WARN_ON(!system_capabilities_finalized()) &&
31 system_supports_fpsimd() &&
32 !in_hardirq() && !irqs_disabled() && !in_nmi();
33}
34
35#else /* ! CONFIG_KERNEL_MODE_NEON */
36
37static __must_check inline bool may_use_simd(void) {
38 return false;
39}
40
41#endif /* ! CONFIG_KERNEL_MODE_NEON */
42
43#endif