| /* 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 */ |
