Re: ath5k: 2.6.32-rc6 "no further txbuf available, dropping packet"

[Bob Copeland <me@bobcopeland.com>]

On Fri, Jan 08, 2010 at 11:34:16PM +0100, Fabio Rossi wrote:
> Hi Bob,
> I have tried your patch as I get many errors as in subject when I transfer 
> huge files (I'm using as a test a 1GB file). With the patch I have the same 
> errors.
> 
> I'm using wireless-testing.git (v2.6.33-rc2-47131-gc72a18c) in managed mode 
> (no AP).

Ok, well the patch only will affect AP mode -- it addresses a bug where
multicast AP frames are queued but not always processed.  I wonder if your
workload is just filling up the queues and then the queues are awakened
prematurely.  There's a check in ath5k_tx_processq to only re-enable the
queue when there are 40 tx buffers left, but there are a few other paths
that re-enable the queues -- also accounting on txbuf_len could theoretically
get broken.

Maybe a printk in ath5k_tx_queue of sc->txbuf_len caN show how many buffers
are typically available when entering?

-- 
Bob Copeland %% www.bobcopeland.com