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Subject: Re: get/put_cpu() usage in block/blk-mq.c
From: Mike Galbraith <efault@gmx.de>
To: Jens Axboe <axboe@fb.com>
Cc: LKML <linux-kernel@vger.kernel.org>
Date: Tue, 09 May 2017 18:26:43 +0200
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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