> >> static int blk_mq_hctx_next_cpu(struct blk_mq_hw_ctx *hctx)
> >> {
> >> - bool tried = false;
> >> int next_cpu = hctx->next_cpu;
> >>
> >> if (hctx->queue->nr_hw_queues == 1)
> >> return WORK_CPU_UNBOUND;
> >>
> >> - if (--hctx->next_cpu_batch <= 0) {
> >> -select_cpu:
> >> - next_cpu = cpumask_next_and(next_cpu, hctx->cpumask,
> >> - cpu_online_mask);
> >> - if (next_cpu >= nr_cpu_ids)
> >> - next_cpu = blk_mq_first_mapped_cpu(hctx);
> >> + if (--hctx->next_cpu_batch > 0 && cpu_online(next_cpu))
> >> + return next_cpu;
> >> +
> >> + next_cpu = cpumask_next_and_wrap(next_cpu, hctx->cpumask, cpu_online_mask, next_cpu, false);
> >
> > Last two parameters are simply useless. In fact, in many cases they
> > are useless for cpumask_next_wrap(). I'm working on simplifying the
> > cpumask_next_wrap() so that it would take just 2 parameters - pivot
> > point and cpumask.
> >
> > Regarding 'next' version - we already have find_next_and_bit_wrap(),
> > and I think cpumask_next_and_wrap() should use it.
> >
>
> Oh, I had missed those, that makes more sense indeed.
>
> > For the context: those last parameters are needed to exclude part of
> > cpumask from traversing, and to implement for-loop. Now that we have
> > for_each_cpu_wrap() based on for_each_set_bit_wrap(), it's possible
> > to remove them. I'm working on it.
>
> Sounds good.
Hi Valentin, all,
I'd like to share my work-in-progress for cpumask_next_wrap(). It's
now in testing (at least, it boots on x86_64 VM).
I'd like to collect early comments on the rework. If you like it, please
align your 'and' version with this.
https://github.com/norov/linux/commits/__bitmap-for-next
Thanks,
Yury
