[PATCH 2/3] ath10k: Grab rcu_read_lock before the txqs spinlock.

Ben Greear greearb at candelatech.com
Mon Sep 12 09:37:46 PDT 2016

On 09/11/2016 11:41 PM, Johannes Berg wrote:
>>>> -	rcu_read_unlock();
>>>>   	spin_unlock_bh(&ar->txqs_lock);
>>>> +	rcu_read_unlock();
>>> I'm no RCU expert but this isn't making any sense. Maybe it changes
>>> timings on your kernel so that it hides the real problem?
>> I'm not sure this fixed anything or not, it just seemed weird so I
>> changed it.
>> I was hoping someone that understood rcu locking would comment...
> RCU is no "locking". The sooner you get over that notion, the better.
> This therefore make no sense whatsoever.
> In fact, you want to keep the RCU protected section *small*, so having
> the spinlock inside hurts overall system performance.

Ok, thanks for the review.  I'll drop this patch from my tree.


Ben Greear <greearb at candelatech.com>
Candela Technologies Inc  http://www.candelatech.com

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