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

Sebastian Andrzej Siewior
2022-09-08T16:01:50Z

On 2022-09-07 22:25:05 [-0400], guoren@kernel.org 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