Re: get/put_cpu() usage in block/blk-mq.c

From: Mike Galbraith
Date: Tue May 09 2017 - 12:26:56 EST


On Tue, 2017-05-09 at 09:45 -0600, Jens Axboe wrote:

> > > > > > Is it from this_cpu_ptr() in blk_stat_add()?
> > > > >
> > > > > Yeah.
> > > >
> > > > So why is this complaining, doesn't rcu_read_lock() disable
> > > > preemption?
> > >
> > > Ah, I guess it doesn't if PREEMPT_RCU is set. How about the
> > > below?
> >
> > Should do it. I was about to run LTP (where it turned up) again
> > anyway, I'll add this. No news is good news, what you should hear.
>
> Thanks, let me know, so I can add your tested-by (or whatever you
> prefer).

Sure, but s/get_cpu_var/get_cpu_ptr first.

-MIke