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Subject: jump-label: disable if stop_machine() is used
From: Thomas Gleixner <tglx@linutronix.de>
Date: Wed Jul 8 17:14:48 2015 +0200
Origin: https://www.kernel.org/pub/linux/kernel/projects/rt/5.15/older/patches-5.15.3-rt21.tar.xz
From: Thomas Gleixner <tglx@linutronix.de>
Some architectures are using stop_machine() while switching the opcode which
leads to latency spikes.
The architectures which use stop_machine() atm:
- ARM stop machine
- s390 stop machine
The architecures which use other sorcery:
- MIPS
- X86
- powerpc
- sparc
- arm64
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
[bigeasy: only ARM for now]
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
arch/arm/Kconfig | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
---
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -68,7 +68,7 @@ config ARM
select HARDIRQS_SW_RESEND
select HAVE_ARCH_AUDITSYSCALL if AEABI && !OABI_COMPAT
select HAVE_ARCH_BITREVERSE if (CPU_32v7M || CPU_32v7) && !CPU_32v6
- select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL && !CPU_ENDIAN_BE32 && MMU
+ select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL && !CPU_ENDIAN_BE32 && MMU && !PREEMPT_RT
select HAVE_ARCH_KGDB if !CPU_ENDIAN_BE32 && MMU
select HAVE_ARCH_KASAN if MMU && !XIP_KERNEL
select HAVE_ARCH_MMAP_RND_BITS if MMU
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