Re: [ath5k-devel] [PATCH 3/5] ath9k: Use common cycle counters

[Bruno Randolf <br1@einfach.org>]

On Wed October 6 2010 05:14:07 Luis R. Rodriguez wrote:
> On Tue, Oct 05, 2010 at 02:55:21AM -0700, Bruno Randolf wrote:
> > Update ath9k to use the common cycle counters.
> > 
> > This also includes other changes from Felix Fietkaus "[PATCH 2/4]
> > ath9k_hw: merge codepaths that access the cycle counter registers".
> > 
> > Compile tested only. ath9k team please review...
> 
> Can you move locking to be specific to the core part of
> the driver instead of the ath9k_hw ?

i'm not sure if i understand what you mean. locking is now implemented in 
ath_common.

> We try to avoid locking
> all over the hardware code. Even ath9k_iowrite32() and
> ath9k_ioread32() are core driver helpers, not part of the
> hw code.

but, we need to make sure the cycle counters are always accessed exclusively. 
e.g. ANI runs from a timer (in ath9k, afaik), and updates the cycle counters. 
at the same time a user might issue a survey, or your debug print may be 
executed, which would want to access the same counters. we need to make sure 
the counters are not updated while they are read, etc...

bruno