File Content: processor.h /* SPDX-License-Identifier: GPL-2.0-only */ /* * Copyright (C) 2020 ARM Ltd. */ #ifndef __ASM_VDSO_PROCESSOR_H #define __ASM_VDSO_PROCESSOR_H #ifndef __ASSEMBLY__ #ifdef CONFIG_CPU_LOONGSON64 /* * Loongson-3's SFB (Store-Fill-Buffer) may buffer writes indefinitely when a * tight read loop is executed, because reads take priority over writes & the * hardware (incorrectly) doesn't ensure that writes will eventually occur. * * Since spin loops of any kind should have a cpu_relax() in them, force an SFB * flush from cpu_relax() such that any pending writes will become visible as * expected. */ #define cpu_relax() smp_mb() #else #define cpu_relax() barrier() #endif #endif /* __ASSEMBLY__ */ #endif /* __ASM_VDSO_PROCESSOR_H */ Submit