> -----Original Message----- > From: Tom Barbette <barbe...@kth.se> > Sent: Friday, August 9, 2019 2:44 PM > To: Pavan Nikhilesh Bhagavatula <pbhagavat...@marvell.com>; Jerin Jacob > Kollanukkaran <jer...@marvell.com>; step...@networkplumber.org; > arybche...@solarflare.com; hemant.agra...@nxp.com; > tho...@monjalon.net; ferruh.yi...@intel.com; > bruce.richard...@intel.com; Neil Horman <nhor...@tuxdriver.com>; John > McNamara <john.mcnam...@intel.com>; Marko Kovacevic > <marko.kovace...@intel.com> > Cc: dev@dpdk.org > Subject: Re: [dpdk-dev] [patch v4] doc: announce API change in ethdev > offload flags > > I think the silent breaking is still not solved for DEV_RX_OFFLOAD_RSS_HASH > and DEV_RX_OFFLOAD_FLOW_MARK.
Unlike ptype, presence of rss hash and flow_mark will be marked in ol_flags as PKT_RX_RSS_HASH and PKT_RX_FDIR_ID. So NO application contract breakage. > > An old application will still compile without any problem, but the RSS hash > will > not be written and the app will break... They should be negative. Eg > DEV_RX_OFFLOAD_NO_RSS_HASH and > DEV_RX_OFFLOAD_NO_FLOW_MARK? > > Then, regarding the idea, are we sure it's better to add a configuration > check/a branch than always copying a few bytes from a warm cache line to a > warm cache line? Or some HW could free some internal resources? But > drivers are free to ignore it so it is not a problem as opposed to silent > breaking. > > Tom > > On 2019-08-09 10:17, pbhagavat...@marvell.com wrote: > > From: Pavan Nikhilesh <pbhagavat...@marvell.com> > > > > Add new offload flags ``DEV_RX_OFFLOAD_RSS`` and > ``DEV_RX_OFFLOAD_FLOW_MARK``. > > Add new function ``rte_eth_dev_set_supported_ptypes`` to allow > application to > > set specific ptypes to be updated in ``rte_mbuf::packet_type`` > > > > Signed-off-by: Pavan Nikhilesh <pbhagavat...@marvell.com> > > Acked-by: Andrew Rybchenko <arybche...@solarflare.com> > > Acked-by: Jerin Jacob <jer...@marvell.com> > > Acked-by: Hemant Agrawal <hemant.agra...@nxp.com> > > --- > > doc/guides/rel_notes/deprecation.rst | 23 +++++++++++++++++++++++ > > 1 file changed, 23 insertions(+) > > > > diff --git a/doc/guides/rel_notes/deprecation.rst > b/doc/guides/rel_notes/deprecation.rst > > index 37b8592b6..e4e2a85d7 100644 > > --- a/doc/guides/rel_notes/deprecation.rst > > +++ b/doc/guides/rel_notes/deprecation.rst > > @@ -78,3 +78,26 @@ Deprecation Notices > > to set new power environment if power environment was already > initialized. > > In this case the function will return -1 unless the environment is unset > first > > (using ``rte_power_unset_env``). Other function usage scenarios will not > change. > > + > > +* ethdev: New offload flags ``DEV_RX_OFFLOAD_RSS_HASH`` and > ``DEV_RX_OFFLOAD_FLOW_MARK`` > > + will be added in 19.11. > > + This will allow application to enable or disable PMDs from updating > > + ``rte_mbuf::hash::rss`` and ``rte_mbuf::hash::fdir`` respectively. > > + This scheme will allow PMDs to avoid writes to ``rte_mbuf`` fields on Rx > and > > + thereby improve Rx performance if application wishes do so. > > + In 19.11 PMDs will still update the fields even when the offloads are not > > + enabled. > > + > > +* ethdev: New function ``rte_eth_dev_set_supported_ptypes`` will be > added in > > + 19.11. > > + This will allow application to request PMD to set specific ptypes defined > > + through ``rte_eth_dev_set_supported_ptypes`` in > ``rte_mbuf::packet_type``. > > + If application doesn't want any ptype information it can call > > + ``rte_eth_dev_set_supported_ptypes(ethdev_id, > RTE_PTYPE_UNKNOWN)`` > > + If application doesn't call ``rte_eth_dev_set_supported_ptypes`` PMD > can > > + return ``rte_mbuf::packet_type`` with > ``rte_eth_dev_get_supported_ptypes``. > > + If application is interested only in L2/L3 layer, it can inform the PMD > > to > update > > + ``rte_mbuf::packet_type`` with L2/L3 ptype by calling > > + ``rte_eth_dev_set_supported_ptypes(ethdev_id, RTE_PTYPE_L2_MASK > | RTE_PTYPE_L3_MASK)``. > > + This scheme will allow PMDs to avoid writes to ``rte_mbuf`` fields on Rx > and > > + thereby improve Rx performance if application wishes do so. > > -- > > 2.17.1 > >
