[PATCH 3/4] ath5k: define ath_common ops

[Luis R. Rodriguez]

On Fri, Sep 11, 2009 at 7:24 AM, Linus Torvalds
<torvalds at linux-foundation.org> wrote:
>
>
> On Fri, 11 Sep 2009, Luis R. Rodriguez wrote:
>>
>> That is the way I had it originally before submission, and I
>> completely agree its reasonable to not incur additional cost at the
>> expense of having two separate read/write paths, and perhaps we should
>> only incur the extra cost on routines shared between
>> ath9k/ath9k/ath9k_htc. But -- is there really is a measurable cost
>> penalty?
>
> There's a measurable size penalty, at least.

My tests so far yield no performance difference but I'm sure there is
some, maybe as Jouni noted, more visible on embedded systems.

> In fact, if you know what kind of IO op it is (ie "it's always MMIO"),
> you'd be even better using "writel()" directly,

Heh.. you realize I tried to document such a thing a while ago and it
seems you opposed it [1]?

[1] http://lkml.indiana.edu/hypermail/linux/kernel/0709.2/0593.html

  Luis