Re: [dpdk-dev] [PATCH v4] mbuf: fix of enabling all newly added RX error flags

[Thomas Monjalon <thomas.monjalon@6wind.com>]

2014-12-10 13:50, Zhang, Helin:
> 
> > -----Original Message-----
> > From: Thomas Monjalon [mailto:thomas.monjalon@6wind.com]
> > Sent: Wednesday, December 10, 2014 5:35 PM
> > To: Zhang, Helin
> > Cc: dev@dpdk.org
> > Subject: Re: [dpdk-dev] [PATCH v4] mbuf: fix of enabling all newly added RX
> > error flags
> > 
> > 2014-12-10 16:55, Helin Zhang:
> > > Before redefining mbuf structure, there was lack of free bits in 'ol_flags'
> > > (32 bits in total) for new RX or TX flags. So it tried to reuse
> > > existant bits as most as possible, or even assigning 0 to some of bit
> > > flags. After new mbuf structure defined, there are quite a lot of free
> > > bits. So those newly added bit flags should be assigned with correct
> > > and valid bit values, and getting their names should be enabled as
> > > well. Note that 'RECIP' should be removed, as nowhere uses it.
> > > 'PKT_RX_ERR' is defined to replace all other error bit flags, e.g. MAC error,
> > Oversize error, header buffer overflow error.
> > >
> > > Signed-off-by: Helin Zhang <helin.zhang@intel.com>
> > > ---
> > >  lib/librte_mbuf/rte_mbuf.c      |  7 ++-----
> > >  lib/librte_mbuf/rte_mbuf.h      |  9 +++------
> > >  lib/librte_pmd_i40e/i40e_rxtx.c | 37
> > > ++++++++++++++++++++-----------------
> > >  3 files changed, 25 insertions(+), 28 deletions(-)
> > >
> > > v2 changes:
> > > * Removed error flag of 'ECIPE' processing only in both i40e PMD and mbuf.
> > All
> > >   other error flags were added back.
> > > * Assigned error flags with correct and valid values, as their previous values
> > >   were invalid.
> > > * Enabled getting all error flag names.
> > >
> > > v3 changes:
> > > * 'PKT_RX_ERR' is defined to replace error bit flags of MAC error, Oversize
> > >   error, header buffer overflow error.
> > > * Removed assigning values to PKT_TX_* bit flags, as it has already been
> > done
> > >   in another packet set.
> > >
> > > v4 changes:
> > > * Renamed 'PKT_RX_EIP_CKSUM_BAD' to 'PKT_RX_OUTER_IP_CKSUM_BAD'.
> > > * Fixed the bug of checking error bits of 'Descriptor oversize' and
> > >   'Header buffer oversize'.
> > > * Added debug logs for each RX error.
> > [...]
> > > --- a/lib/librte_mbuf/rte_mbuf.h
> > > +++ b/lib/librte_mbuf/rte_mbuf.h
> > > @@ -83,12 +83,7 @@ extern "C" {
> > >  #define PKT_RX_RSS_HASH      (1ULL << 1)  /**< RX packet with RSS
> > hash result. */
> > >  #define PKT_RX_FDIR          (1ULL << 2)  /**< RX packet with FDIR
> > match indicate. */
> > >  #define PKT_RX_L4_CKSUM_BAD  (1ULL << 3)  /**< L4 cksum of RX pkt.
> > is
> > > not OK. */ -#define PKT_RX_IP_CKSUM_BAD  (1ULL << 4)  /**< IP cksum of
> > > RX pkt. is not OK. */ -#define PKT_RX_EIP_CKSUM_BAD (0ULL << 0)  /**<
> > External IP header checksum error. */
> > > -#define PKT_RX_OVERSIZE      (0ULL << 0)  /**< Num of desc of an RX
> > pkt oversize. */
> > > -#define PKT_RX_HBUF_OVERFLOW (0ULL << 0)  /**< Header buffer
> > overflow. */
> > > -#define PKT_RX_RECIP_ERR     (0ULL << 0)  /**< Hardware processing
> > error. */
> > > -#define PKT_RX_MAC_ERR       (0ULL << 0)  /**< MAC error. */
> > > +#define PKT_RX_IP_CKSUM_BAD  (1ULL << 4)  /**< IP (or inner IP)
> > > +header checksum error. */
> > 
> > It can be also an outer IP header in case the device don't support tunneling or is
> > not configured to detect it.
> 
> For non-tunneling case, no outer/inner at all, it just has the IP header. The bit flag
> indicates the IP header checksum error.
> For tunneling case, this bit flag indicates the inner IP header checksum error, another
> one for outer IP header checksum error.
> So I don't think this bit can be treated as outer.

I think you didn't understand my comment.
I talk about NICs which don't have tunneling support.
In this case, the outer IP header is seen as a simple IP header.
So, depending on which port is receiving a tunneled packet, this
flag or the dedicated one can be used for outer IP checksum.

I just suggest to remove the part "(or inner IP)" of the comment.
Do you agree?

-- 
Thomas