Re: [PATCH] ARM: support PREEMPT_DYNAMIC

From: Jinjie Ruan
Date: Wed Jul 31 2024 - 05:25:23 EST




On 2024/7/31 16:24, Russell King (Oracle) wrote:
> On Wed, Jul 31, 2024 at 10:07:53AM +0800, Jinjie Ruan wrote:
>>> #ifdef CONFIG_PREEMPTION
>>> +#ifdef CONFIG_PREEMPT_DYNAMIC
>>> + bl need_irq_preemption
>>> + cmp r0, #0
>>> + beq 2f
>>> +#endif
>
> Depending on the interrupt rate, this can be regarded as a fast path,
> it would be nice if we could find a way to use static branches in
> assembly code.

You're right, it's more elegant to use dynamic keys in assembly, let me
think about how to do it.

>