> -----Original Message----- > From: dev [mailto:dev-bounces at dpdk.org] On Behalf Of Bruce Richardson > Sent: Tuesday, September 09, 2014 3:41 PM > To: dev at dpdk.org > Subject: [dpdk-dev] [PATCH v3 6/6] mbuf: flatten struct vlan_macip into > mbuf struct > > The vlan_macip structure combined a vlan tag id with l2 and l3 headers > lengths for tracking offloads. However, this structure was only used as > a unit by the e1000 and ixgbe drivers, not generally. > > This patch removes the structure from the mbuf header and places the > fields into the mbuf structure directly at the required point, without > any net effect on the structure layout. This allows us to treat the vlan > tags and header length fields as separate for future mbuf changes. The > drivers which were written to use the combined structure still do so, > using a driver-local definition of it. > > Changes in V2: > * None > > Changes in V3: > * minor comment cleanup following review by Olivier > * reduce perf regression caused by splitting vlan_macip field. This is > done by providing a single uint16_t value to allow writing/clearing > the l2 and l3 lengths together. There is still a small perf hit to the > slow path TX due to the reads from vlan_tci and l2/l3 lengths being > separated. (<5% in my tests with testpmd with no extra params). > Unfortunately, this cannot be eliminated, without restoring the vlan > tags and l2/l3 lengths as a combined 32-bit field. This would prevent > us from ever looking to move those fields about and is an artificial tie > that applies only for performance in igb and ixgbe drivers. Therefore, > this patch keeps the vlan_tci field separate from the lengths as the > best solution going forward. > > Signed-off-by: Bruce Richardson <bruce.richardson at intel.com> > V2 Acked-by: Olivier Matz <olivier.matz at 6wind.com>
V3 Acked-by: Pablo de Lara <pablo.de.lara.guarch at intel.com>