Subject: Re: [PATCH] Optimize loopback stats

From: Nivedita Singhvi <[email-masked]>
Date: Tue, 15 Mar 2005 16:09:43 -0800

Chuck Ebbert wrote:

> On 15-Mar-05 Nivedita Singhvi wrote:
> 
> 
>>Chuck Ebbert wrote:
>>
>>
>>>  This patch optimizes the loopback driver's statistics by using a single
>>>counter for rx and tx stats instead of one for rx and one for tx.  It also
>>>adds unlikely() to the test for TSO since it's no longer supported by default.
>>>(Maybe the TSO code should be bracketed by "#if 0" ?)
>>
>>Hmm, some of us want those counters separate - if this is really
>>needed, could it be a configurable option, please?
> 
> 
>  But they _are_ separately reported -- get_stats() takes care of that.
> Everything looks exactly the same to userspace after this patch.
> 
> 
> 
> 
> --
> Chuck
> 
Hmm, I see the following in your patch:

+               stats->rx_bytes   += lb_stats->rx_tx_bytes;
+               stats->tx_bytes    = stats->rx_bytes;

Doesn't that mean RX is now twice what it should be
and so is TX? They are separately reported, but if
so, their real value should be half of rx_tx_bytes
each, correct?

thanks,
Nivedita