Re: [PATCH] ipc/msg: Implement lockless pipelined wakeups

[Sebastian Andrzej Siewior]

On 10/31/2015 07:54 PM, Davidlohr Bueso wrote:
>> However, a wake_q keeps a reference to a task, so exiting is
>> not a danger.  As long as wake_q_add precedes setting r_msg,
>> all is well.
> 
> Yes, and this confirms that we still rely on the implicit barrier
> from the cmpxchg as tglx mentioned. As such, we also need to keep
> the pairing when reading 'r_msg' in do_msgrcv(), instead of dropping
> the comments.

Okay, I took the memory-barrier comment from your mqueue patch and
adjusted.

> 
> Thanks,
> Davidlohr

Sebastian
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