diff options
Diffstat (limited to 'arch/arm64/include/asm/simd.h')
| -rw-r--r-- | arch/arm64/include/asm/simd.h | 30 |
1 files changed, 16 insertions, 14 deletions
diff --git a/arch/arm64/include/asm/simd.h b/arch/arm64/include/asm/simd.h index 6495cc51246f..0941f6f58a14 100644 --- a/arch/arm64/include/asm/simd.h +++ b/arch/arm64/include/asm/simd.h @@ -1,23 +1,21 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ /* * Copyright (C) 2017 Linaro Ltd. <ard.biesheuvel@linaro.org> - * - * This program is free software; you can redistribute it and/or modify it - * under the terms of the GNU General Public License version 2 as published - * by the Free Software Foundation. */ #ifndef __ASM_SIMD_H #define __ASM_SIMD_H +#include <linux/cleanup.h> #include <linux/compiler.h> #include <linux/irqflags.h> #include <linux/percpu.h> #include <linux/preempt.h> #include <linux/types.h> -#ifdef CONFIG_KERNEL_MODE_NEON +#include <asm/neon.h> -DECLARE_PER_CPU(bool, kernel_neon_busy); +#ifdef CONFIG_KERNEL_MODE_NEON /* * may_use_simd - whether it is allowable at this time to issue SIMD @@ -29,15 +27,12 @@ DECLARE_PER_CPU(bool, kernel_neon_busy); static __must_check inline bool may_use_simd(void) { /* - * kernel_neon_busy is only set while preemption is disabled, - * and is clear whenever preemption is enabled. Since - * this_cpu_read() is atomic w.r.t. preemption, kernel_neon_busy - * cannot change under our feet -- if it's set we cannot be - * migrated, and if it's clear we cannot be migrated to a CPU - * where it is set. + * We must make sure that the SVE has been initialized properly + * before using the SIMD in kernel. */ - return !in_irq() && !irqs_disabled() && !in_nmi() && - !this_cpu_read(kernel_neon_busy); + return !WARN_ON(!system_capabilities_finalized()) && + system_supports_fpsimd() && + !in_hardirq() && !in_nmi(); } #else /* ! CONFIG_KERNEL_MODE_NEON */ @@ -48,4 +43,11 @@ static __must_check inline bool may_use_simd(void) { #endif /* ! CONFIG_KERNEL_MODE_NEON */ +DEFINE_LOCK_GUARD_1(ksimd, + struct user_fpsimd_state, + kernel_neon_begin(_T->lock), + kernel_neon_end(_T->lock)) + +#define scoped_ksimd() scoped_guard(ksimd, &(struct user_fpsimd_state){}) + #endif |