Re: [PATCH 3/4] brcmfmac: rework headroom check in .start_xmit()

[Kalle Valo <kvalo@codeaurora.org>]

Arend van Spriel <arend.vanspriel@broadcom.com> writes:

> On 27-06-17 16:09, Kalle Valo wrote:
>> Arend van Spriel <arend.vanspriel@broadcom.com> writes:
>> 
>>> Since commit 9cc4b7cb86cb ("brcmfmac: Make skb header writable
>>> before use") the headroom usage has been fixed. However, the
>>> driver was keeping statistics that got lost. So reworking the
>>> code so we get those driver statistics back for debugging.
>>>
>>> Cc: James Hughes <james.hughes@raspberrypi.org>
>>> Reviewed-by: Hante Meuleman <hante.meuleman@broadcom.com>
>>> Reviewed-by: Pieter-Paul Giesberts <pieter-paul.giesberts@broadcom.com>
>>> Reviewed-by: Franky Lin <franky.lin@broadcom.com>
>>> Signed-off-by: Arend van Spriel <arend.vanspriel@broadcom.com>
>>> ---
>>>  .../net/wireless/broadcom/brcm80211/brcmfmac/bus.h | 15 ++++++++++++--
>>>  .../wireless/broadcom/brcm80211/brcmfmac/core.c    | 23 +++++++++++++++-------
>>>  .../wireless/broadcom/brcm80211/brcmfmac/sdio.c    | 13 +++++++-----
>>>  3 files changed, 37 insertions(+), 14 deletions(-)
>>>
>>> diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/bus.h
>>> b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/bus.h
>>> index e1a4d9e..163ddc4 100644
>>> --- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/bus.h
>>> +++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/bus.h
>>> @@ -113,6 +113,17 @@ struct brcmf_bus_msgbuf {
>>>  
>>>  
>>>  /**
>>> + * struct brcmf_bus_stats - bus statistic counters.
>>> + *
>>> + * @pktcowed: packets cowed for extra headroom/unorphan.
>>> + * @pktcow_failed: packets dropped due to failed cow-ing.
>>> + */
>>> +struct brcmf_bus_stats {
>>> +	atomic_t pktcowed;
>>> +	atomic_t pktcow_failed;
>>> +};
>> 
>> Same question as in the previous patch. I only see updates for these
>> variables, but nobody reading them?
>
> Hi Kalle,
>
> You are right. My intention was to expose these to debugfs, but clearly
> did not include it in this patch series. So how do you want to handle
> this. Feel free to drop patch 2 and 3. I can resubmit them with
> subsequent patches dealing with exposing it to debugfs if that makes
> more sense.

No need to resend if you are going to add the debugfs interface soon.
But the general rule is that we don't add any dead code to kernel and
there was no explanation in the commit log, that's why I asked.

-- 
Kalle Valo