Hi Andrew,
On Thu, Mar 28, 2019 at 08:04:31PM +0300, Andrew Rybchenko wrote:
> Ping? (I have a number of net/sfc patches which heavily depend on this
> one and must not be applied without this one)
>
> Andrew.
>
> On 2/19/19 9:30 AM, Andrew Rybchenko wrote:
> > rte_validate_tx_offload() is used in Tx prepare callbacks
> > (RTE_LIBRTE_ETHDEV_DEBUG only) to check Tx offloads consistency.
> > Requirement that packet headers should not be fragmented is not
> > documented and unclear where it comes from except
> > rte_net_intel_cksum_prepare() functions which relies on it.
> >
> > It could be NIC vendor specific driver or hardware limitation, but,
> > if so, it should be documented and checked in corresponding Tx
> > prepare callbacks.
> >
> > Signed-off-by: Andrew Rybchenko <arybche...@solarflare.com>
> > Acked-by: Konstantin Ananyev <konstantin.anan...@intel.com>
> > ---
> > Looks good to me, though extra-testing would be needed.
> > Konstantin Ananyev <konstantin.anan...@intel.com>
> >
> > lib/librte_mbuf/rte_mbuf.h | 12 ------------
> > lib/librte_net/rte_net.h | 17 +++++++++++++++++
> > 2 files changed, 17 insertions(+), 12 deletions(-)
> >
> > diff --git a/lib/librte_mbuf/rte_mbuf.h b/lib/librte_mbuf/rte_mbuf.h
> > index d961cca..73daa81 100644
> > --- a/lib/librte_mbuf/rte_mbuf.h
> > +++ b/lib/librte_mbuf/rte_mbuf.h
> > @@ -2257,23 +2257,11 @@ static inline int rte_pktmbuf_chain(struct rte_mbuf
> > *head, struct rte_mbuf *tail
> > rte_validate_tx_offload(const struct rte_mbuf *m)
> > {
> > uint64_t ol_flags = m->ol_flags;
> > - uint64_t inner_l3_offset = m->l2_len;
> > /* Does packet set any of available offloads? */
> > if (!(ol_flags & PKT_TX_OFFLOAD_MASK))
> > return 0;
> > - if (ol_flags & PKT_TX_OUTER_IP_CKSUM)
> > - /* NB: elaborating the addition like this instead of using
> > - * += gives the result uint64_t type instead of int,
> > - * avoiding compiler warnings on gcc 8.1 at least */
> > - inner_l3_offset = inner_l3_offset + m->outer_l2_len +
> > - m->outer_l3_len;
> > -
> > - /* Headers are fragmented */
> > - if (rte_pktmbuf_data_len(m) < inner_l3_offset + m->l3_len + m->l4_len)
> > - return -ENOTSUP;
> > -
> > /* IP checksum can be counted only for IPv4 packet */
> > if ((ol_flags & PKT_TX_IP_CKSUM) && (ol_flags & PKT_TX_IPV6))
> > return -EINVAL;
> > diff --git a/lib/librte_net/rte_net.h b/lib/librte_net/rte_net.h
> > index e59760a..bd75aea 100644
> > --- a/lib/librte_net/rte_net.h
> > +++ b/lib/librte_net/rte_net.h
> > @@ -118,10 +118,27 @@ uint32_t rte_net_get_ptype(const struct rte_mbuf *m,
> > struct udp_hdr *udp_hdr;
> > uint64_t inner_l3_offset = m->l2_len;
> > + /*
> > + * Does packet set any of available offloads?
> > + * Mainly it is required to avoid fragmented headers check if
> > + * no offloads are requested.
> > + */
> > + if (!(ol_flags & PKT_TX_OFFLOAD_MASK))
> > + return 0;
> > +
> > if ((ol_flags & PKT_TX_OUTER_IP_CKSUM) ||
> > (ol_flags & PKT_TX_OUTER_IPV6))
> > inner_l3_offset += m->outer_l2_len + m->outer_l3_len;
> > + /*
> > + * Check if headers are fragmented.
> > + * The check could be less strict depending on which offloads are
> > + * requested and headers to be used, but let's keep it simple.
> > + */
> > + if (unlikely(rte_pktmbuf_data_len(m) <
> > + inner_l3_offset + m->l3_len + m->l4_len))
> > + return -ENOTSUP;
> > +
> > if (ol_flags & PKT_TX_IPV4) {
> > ipv4_hdr = rte_pktmbuf_mtod_offset(m, struct ipv4_hdr *,
> > inner_l3_offset);
>
To summarize, the previous code was in a generic part, only enabled if
RTE_LIBRTE_ETHDEV_DEBUG is set, and it is moved in an intel-specific part,
but always enabled. Am I correct?
So it may have a performance impact on intel NICs. Shouldn't it be under
a debug option?
Regards,
Olivier
