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From: Adrian Chadd <adrian@freebsd.org>
To: Warner Losh <imp@bsdimp.com>
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Subject: Re: newbus bus access routines and bus_space_barrier()
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On 16 October 2011 11:45, Warner Losh <imp@bsdimp.com> wrote:
> Usually they are needed, but we get away without them often because they are needed in a limited set of circumstances and we have memory barriers in our locking primitives.

Hm, so should this actively be fixed for drivers? I note iwn(4) does
its own (correct looking?) barrier stuff. A few other drivers do. ath
doesn't (yet).
wi(4) doesn't yet do barriers, but someone supplied a patch that may
work better on ppc if said barriers are included.

Thanks,


Adrian