On Tue, Aug 19, 2025 at 09:58:31AM +0800, Menglong Dong wrote:
> The "struct rq" is not available in include/linux/sched.h, so we can't
> access the "runqueues" with this_cpu_ptr(), as the compilation will fail
> in this_cpu_ptr() -> raw_cpu_ptr() -> __verify_pcpu_ptr():
> typeof((ptr) + 0)
>
> So we introduce the this_rq_raw() and access the runqueues with
> arch_raw_cpu_ptr() directly.
^ That, wants to be a comment near here:
> @@ -2312,4 +2315,78 @@ static __always_inline void alloc_tag_restore(struct alloc_tag *tag, struct allo
> #define alloc_tag_restore(_tag, _old) do {} while (0)
> #endif
>
> +#ifndef COMPILE_OFFSETS
> +
> +extern void __migrate_enable(void);
> +
> +struct rq;
> +DECLARE_PER_CPU_SHARED_ALIGNED(struct rq, runqueues);
> +
> +#ifdef CONFIG_SMP
> +#define this_rq_raw() arch_raw_cpu_ptr(&runqueues)
> +#else
> +#define this_rq_raw() PERCPU_PTR(&runqueues)
> +#endif
Because that arch_ thing really is weird.
> + (*(unsigned int *)((void *)this_rq_raw() + RQ_nr_pinned))--;
> + (*(unsigned int *)((void *)this_rq_raw() + RQ_nr_pinned))++;
And since you did a macro anyway, why not fold that magic in there,
instead of duplicating it?
#define __this_rq_raw() ((void *)arch_raw_cpu_ptr(&runqueues))
#define this_rq_pinned() (*(unsigned int *)(__this_rq_raw() + RQ_nr_pinned))
this_rq_pinned()--;
this_rq_pinned()++;
is nicer, no?
