On Tue, 2 Jan 2018, Geert Uytterhoeven wrote:
> On uniprocessor systems, critical and non-critical tasks cannot be
> isolated, as there is only a single CPU core. Hence enabling CPU
> isolation by default on such systems does not make much sense.
>
> Instead of changing the default for !SMP, fix this by making the feature
> depend on SMP, with an override for compile-testing. Note that its sole
> selector (NO_HZ_FULL) already depends on SMP.
>
> This decreases kernel size for a default uniprocessor kernel by ca. 1
> KiB.
>
> Fixes: 2c43838c99d9d23f ("sched/isolation: Enable CONFIG_CPU_ISOLATION=y by
> default")
> Signed-off-by: Geert Uytterhoeven <ge...@linux-m68k.org>
Acked-by: Nicolas Pitre <n...@linaro.org>
> ---
> init/Kconfig | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/init/Kconfig b/init/Kconfig
> index 690a381adee0d164..c1221332e128c700 100644
> --- a/init/Kconfig
> +++ b/init/Kconfig
> @@ -461,6 +461,7 @@ endmenu # "CPU/Task time and stats accounting"
>
> config CPU_ISOLATION
> bool "CPU isolation"
> + depends on SMP || COMPILE_TEST
> default y
> help
> Make sure that CPUs running critical tasks are not disturbed by
> --
> 2.7.4
>
>
