[dpdk-dev] [PATCH v2 06/13] mbuf: add functions to get the name of an ol_flag

[Ananyev, Konstantin]

> -----Original Message-----
> From: Olivier MATZ [mailto:olivier.matz at 6wind.com]
> Sent: Tuesday, November 18, 2014 9:30 AM
> To: Ananyev, Konstantin; dev at dpdk.org
> Cc: jigsaw at gmail.com; Zhang, Helin
> Subject: Re: [dpdk-dev] [PATCH v2 06/13] mbuf: add functions to get the name of an ol_flag
> 
> Hi Konstantin,
> 
> On 11/17/2014 08:00 PM, Ananyev, Konstantin wrote:
> >> +/*
> >> + * Get the name of a RX offload flag
> >> + */
> >> +const char *rte_get_rx_ol_flag_name(uint64_t mask)
> >> +{
> >> +	switch (mask) {
> >> +	case PKT_RX_VLAN_PKT: return "PKT_RX_VLAN_PKT";
> >> +	case PKT_RX_RSS_HASH: return "PKT_RX_RSS_HASH";
> >> +	case PKT_RX_FDIR: return "PKT_RX_FDIR";
> >> +	case PKT_RX_L4_CKSUM_BAD: return "PKT_RX_L4_CKSUM_BAD";
> >> +	case PKT_RX_IP_CKSUM_BAD: return "PKT_RX_IP_CKSUM_BAD";
> >> +	/* case PKT_RX_EIP_CKSUM_BAD: return "PKT_RX_EIP_CKSUM_BAD"; */
> >> +	/* case PKT_RX_OVERSIZE: return "PKT_RX_OVERSIZE"; */
> >> +	/* case PKT_RX_HBUF_OVERFLOW: return "PKT_RX_HBUF_OVERFLOW"; */
> >> +	/* case PKT_RX_RECIP_ERR: return "PKT_RX_RECIP_ERR"; */
> >> +	/* case PKT_RX_MAC_ERR: return "PKT_RX_MAC_ERR"; */
> >
> > Didn't spot it before, wonder why do you need these 5 commented out lines?
> > In fact, why do we need these flags if they all equal to zero right now?
> > I know these flags were not introduced by that patch, in fact as I can see it was a temporary measure,
> > as old ol_flags were just 16 bits long:
> > http://dpdk.org/ml/archives/dev/2014-June/003308.html
> > So wonder should now these flags either get proper values or be removed?
> 
> I would be in favor of removing them, or at least the following ones
> (I don't understand how they can help the application):
> 
> - PKT_RX_OVERSIZE: Num of desc of an RX pkt oversize.
> - PKT_RX_HBUF_OVERFLOW: Header buffer overflow.
> - PKT_RX_RECIP_ERR: Hardware processing error.
> - PKT_RX_MAC_ERR: MAC error.

Tend to agree...
Or probably collapse these 4 flags into one: flag PKT_RX_ERR or something.
Might be still used by someone for debugging purposes.
Helin, what do you think?

> 
> I would have say that a statistics counter in the driver is more
> appropriate for this case (maybe there is already a counter in the
> hardware).
> 
> I have no i40e hardware to test that, so I don't feel very comfortable
> to modify the i40e driver code to add these stats.
> 
> Adding Helin in CC list, maybe he has an idea.
> 
> Regards,
> Olivier