Missing memory barriers

Kalle Valo kvalo at qca.qualcomm.com
Thu Feb 27 10:48:46 EST 2014


Hi Avery,

starting a new thread about memory barriers:

Avery Pennarun <apenwarr at gmail.com> writes:

> On Wed, Jan 29, 2014 at 9:41 PM, Avery Pennarun <apenwarr at gmail.com> wrote:
>
> - there are definitely some missing memory barriers in here; in a few
> cases you can clearly see a write getting done before the read that
> came before it.  Looking at the definitions for iowrite32 and
> ioread32, and for rmb() and wmb(), we can see that the use of rmb()
> and wmb() do not work properly (at least on ARM) when you care about
> the ordering between reads and writes.  However, I don't think this
> actually causes the problem.

Can you tell more about this, please? Did you find out where we are
actually doing it wrong?

-- 
Kalle Valo



More information about the ath10k mailing list