> +#else
> +static inline bool can_hotplug_cpu(void) { return 0; }
> +static inline void arch_send_call_wakeup_ipi(int cpu) { }
Please use normal coding style for these stubs.
> #define INTERRUPT_CAUSE_FLAG (1UL << (__riscv_xlen - 1))
> +#define get_scause(cause) (cause & ~INTERRUPT_CAUSE_FLAG)
I think this helper is misleading - the cause includes the interrupt
flag. I'd rather open code this in the other place as well.
> diff --git a/arch/riscv/kernel/process.c b/arch/riscv/kernel/process.c
> index d7c6ca7c..cb209139 100644
> --- a/arch/riscv/kernel/process.c
> +++ b/arch/riscv/kernel/process.c
> @@ -42,6 +42,13 @@ void arch_cpu_idle(void)
> local_irq_enable();
> }
>
> +#ifdef CONFIG_HOTPLUG_CPU
> +void arch_cpu_idle_dead(void)
> +{
> + cpu_play_dead();
> +}
> +#endif
I wonder if it might be worth to introduce a small
arch/riscv/kernel/cpu-hotplug.c file for the various CONFIG_HOTPLUG_CPU
only functions.
