On 1/14/20 5:06 AM, Hsin-Yi Wang wrote: > This patch adds a config ARCH_OFFLINE_CPUS_ON_REBOOT, which would offline cpus in > migrate_to_reboot_cpu(). If non reboot cpus are all offlined here, the loop for > checking online cpus would be an empty loop. If architecture don't enable this > config, or some cpus somehow fails to offline, it would fallback to ipi > function. I'm curious: > +# Select to do a full offline on secondary CPUs before reboot. > +config ARCH_OFFLINE_CPUS_ON_REBOOT > + bool "Support for offline CPUs before reboot" > + depends on HOTPLUG_CPU The new symbol can't be selected without the other symbol. > + select ARCH_OFFLINE_CPUS_ON_REBOOT if HOTPLUG_CPU And the other symbol automatically selects the new one. Why are you adding a second symbol that means the same thing as the existing symbol? > +#if defined(CONFIG_PM_SLEEP_SMP) || defined(CONFIG_ARCH_OFFLINE_CPUS_ON_REBOOT) > +extern int freeze_secondary_cpus(int primary, bool reboot); > +#endif Couldn't that just test HOTPLUG_CPU? What's the second symbol for? (You can have empty stub functions when architectures don't support a thing...) Rob
