Re: [PATCH V4 7/8] riscv: Support HAVE_SOFTIRQ_ON_OWN_STACK

[Sebastian Andrzej Siewior]

On 2022-09-07 22:25:05 [-0400], guoren@xxxxxxxxxx wrote:
> --- a/arch/riscv/kernel/irq.c
> +++ b/arch/riscv/kernel/irq.c
> @@ -11,6 +11,7 @@
>  #include <linux/seq_file.h>
>  #include <asm/smp.h>
>  #include <asm/vmap_stack.h>
> +#include <asm/softirq_stack.h>
>  
>  #ifdef CONFIG_IRQ_STACKS
>  static DEFINE_PER_CPU(ulong *, irq_stack_ptr);
> @@ -38,6 +39,21 @@ static void init_irq_stacks(void)
>  		per_cpu(irq_stack_ptr, cpu) = per_cpu(irq_stack, cpu);
>  }
>  #endif /* CONFIG_VMAP_STACK */
> +
> +#ifndef CONFIG_PREEMPT_RT

Could you please replace it with 
	#ifdef CONFIG_SOFTIRQ_ON_OWN_STACK

instead? See
	https://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic.git/commit/?id=8cbb2b50ee2dcb082675237eaaa48fe8479f8aa5

> +static void do_riscv_softirq(struct pt_regs *regs)
> +{
> +	__do_softirq();
> +}
> +
> +void do_softirq_own_stack(void)
> +{
> +	ulong *sp = per_cpu(irq_stack_ptr, smp_processor_id());
> +
> +	call_on_stack(NULL, sp, do_riscv_softirq, 0);
> +}
> +#endif /* CONFIG_PREEMPT_RT */
> +
>  #else
>  static void init_irq_stacks(void) {}
>  #endif /* CONFIG_IRQ_STACKS */

Sebastian