2016-05-17 22:40:10 +00:00
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Subject: jump-label: disable if stop_machine() is used
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From: Thomas Gleixner <tglx@linutronix.de>
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Date: Wed, 08 Jul 2015 17:14:48 +0200
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2016-12-12 19:54:49 +00:00
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Origin: https://www.kernel.org/pub/linux/kernel/projects/rt/4.8/older/patches-4.8.14-rt9.tar.xz
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2016-05-17 22:40:10 +00:00
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Some architectures are using stop_machine() while switching the opcode which
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leads to latency spikes.
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The architectures which use stop_machine() atm:
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- ARM stop machine
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- s390 stop machine
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The architecures which use other sorcery:
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- MIPS
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- X86
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- powerpc
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- sparc
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- arm64
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Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
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[bigeasy: only ARM for now]
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Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
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---
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arch/arm/Kconfig | 2 +-
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1 file changed, 1 insertion(+), 1 deletion(-)
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--- a/arch/arm/Kconfig
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+++ b/arch/arm/Kconfig
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2016-10-11 18:58:48 +00:00
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@@ -36,7 +36,7 @@ config ARM
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2016-05-17 22:40:10 +00:00
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select HAVE_ARCH_AUDITSYSCALL if (AEABI && !OABI_COMPAT)
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select HAVE_ARCH_BITREVERSE if (CPU_32v7M || CPU_32v7) && !CPU_32v6
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2016-10-11 18:58:48 +00:00
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select HAVE_ARCH_HARDENED_USERCOPY
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2016-05-17 22:40:10 +00:00
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- select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL && !CPU_ENDIAN_BE32 && MMU
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+ select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL && !CPU_ENDIAN_BE32 && MMU && !PREEMPT_RT_BASE
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select HAVE_ARCH_KGDB if !CPU_ENDIAN_BE32 && MMU
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select HAVE_ARCH_MMAP_RND_BITS if MMU
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select HAVE_ARCH_SECCOMP_FILTER if (AEABI && !OABI_COMPAT)
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