Re: [PATCH v2] RISC-V: Fix use of non existent CONFIG_HAVE_SOFTIRQ_ON_OWN_STACK

[Samuel Holland <samuel@sholland.org>]

Hi,

The patch is correct, though the subject isn't quite accurate.
CONFIG_HAVE_SOFTIRQ_ON_OWN_STACK exists; it is defined in arch/Kconfig.
It's just the wrong option to use to guard the function definition.

On 9/6/23 07:32, Jiexun Wang wrote:
> If configuration options SOFTIRQ_ON_OWN_STACK and PREEMPT_RT 
> are enabled simultaneously under RISC-V architecture,
> it will result in a compilation failure:
> 
> arch/riscv/kernel/irq.c:64:6: error: redefinition of 'do_softirq_own_stack'
>    64 | void do_softirq_own_stack(void)
>       |      ^~~~~~~~~~~~~~~~~~~~
> In file included from ./arch/riscv/include/generated/asm/softirq_stack.h:1,
>                  from arch/riscv/kernel/irq.c:15:
> ./include/asm-generic/softirq_stack.h:8:20: note: previous definition of 'do_softirq_own_stack' was here
>     8 | static inline void do_softirq_own_stack(void)
>       |                    ^~~~~~~~~~~~~~~~~~~~
>       
> After changing CONFIG_HAVE_SOFTIRQ_ON_OWN_STACK to CONFIG_SOFTIRQ_ON_OWN_STACK,
> compilation can be successful.
> 
> Fixes: dd69d07a5a6c ("riscv: stack: Support HAVE_SOFTIRQ_ON_OWN_STACK")
> Signed-off-by: Jiexun Wang <wangjiexun@tinylab.org>
> ---
> Changes in v2:
> - changed to a more suitable subject line
> - add a Fixes tag
> 
> ---
>  arch/riscv/kernel/irq.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/arch/riscv/kernel/irq.c b/arch/riscv/kernel/irq.c
> index a8efa053c4a5..a86f272ae2c3 100644
> --- a/arch/riscv/kernel/irq.c
> +++ b/arch/riscv/kernel/irq.c
> @@ -60,7 +60,7 @@ static void init_irq_stacks(void)
>  }
>  #endif /* CONFIG_VMAP_STACK */
>  
> -#ifdef CONFIG_HAVE_SOFTIRQ_ON_OWN_STACK
> +#ifdef CONFIG_SOFTIRQ_ON_OWN_STACK

It would be good to fix the #endif comment at the bottom of the function
as well.

Regards,
Samuel

>  void do_softirq_own_stack(void)
>  {
>  #ifdef CONFIG_IRQ_STACKS