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Diffstat (limited to 'arch/s390/Kconfig')
| -rw-r--r-- | arch/s390/Kconfig | 17 |
1 files changed, 17 insertions, 0 deletions
diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig index 5fd4a67c93b3..080a3fcc3cb8 100644 --- a/arch/s390/Kconfig +++ b/arch/s390/Kconfig @@ -537,6 +537,22 @@ config ARCH_RANDOM If unsure, say Y. +config ALTERNATIVES + def_bool y + prompt "Patch optimized instructions for running CPU type" + help + When enabled the kernel code is compiled with additional + alternative instructions blocks optimized for newer CPU types. + These alternative instructions blocks are patched at kernel boot + time when running CPU supports them. This mechanism is used to + optimize some critical code paths (i.e. spinlocks) for newer CPUs + even if kernel is build to support older machine generations. + + This mechanism could be disabled by appending "noaltinstr" + option to the kernel command line. + + If unsure, say Y. + endmenu menu "Memory setup" @@ -811,6 +827,7 @@ config PFAULT config SHARED_KERNEL bool "VM shared kernel support" depends on !JUMP_LABEL + depends on !ALTERNATIVES help Select this option, if you want to share the text segment of the Linux kernel between different VM guests. This reduces memory |