This patch adds GSO support for UDP/IPv4 packets. Supported packets
may include a single VLAN tag. UDP/IPv4 GSO doesn't check if input
packets have correct checksums, and doesn't update checksums for
output packets (the responsibility for this lies with the application).
Additionally, UDP/IPv4 GSO doesn't process IP fragmented packets.
UDP/IPv4 GSO uses two chained MBUFs, one direct MBUF and one indrect
MBUF, to organize an output packet. The direct MBUF stores the packet
header, while the indirect mbuf simply points to a location within the
original packet's payload. Consequently, use of UDP GSO requires
multi-segment MBUF support in the TX functions of the NIC driver.
If a packet is GSO'd, UDP/IPv4 GSO reduces its MBUF refcnt by 1. As a
result, when all of its GSOed segments are freed, the packet is freed
automatically.
Signed-off-by: Jiayu Hu <jiayu.hu@intel.com>
Acked-by: Xiao Wang <xiao.w.wang@intel.com>
Replace the BSD license header with the SPDX tag for files
with only an Intel copyright on them.
Signed-off-by: Bruce Richardson <bruce.richardson@intel.com>
This patch adds GSO support for TCP/IPv4 packets. Supported packets
may include a single VLAN tag. TCP/IPv4 GSO doesn't check if input
packets have correct checksums, and doesn't update checksums for
output packets (the responsibility for this lies with the application).
Additionally, TCP/IPv4 GSO doesn't process IP fragmented packets.
TCP/IPv4 GSO uses two chained MBUFs, one direct MBUF and one indrect
MBUF, to organize an output packet. Note that we refer to these two
chained MBUFs as a two-segment MBUF. The direct MBUF stores the packet
header, while the indirect mbuf simply points to a location within the
original packet's payload. Consequently, use of the GSO library requires
multi-segment MBUF support in the TX functions of the NIC driver.
If a packet is GSO'd, TCP/IPv4 GSO reduces its MBUF refcnt by 1. As a
result, when all of its GSOed segments are freed, the packet is freed
automatically.
Signed-off-by: Jiayu Hu <jiayu.hu@intel.com>
Signed-off-by: Mark Kavanagh <mark.b.kavanagh@intel.com>
Acked-by: Konstantin Ananyev <konstantin.ananyev@intel.com>
Tested-by: Lei Yao <lei.a.yao@intel.com>
Generic Segmentation Offload (GSO) is a SW technique to split large
packets into small ones. Akin to TSO, GSO enables applications to
operate on large packets, thus reducing per-packet processing overhead.
To enable more flexibility to applications, DPDK GSO is implemented
as a standalone library. Applications explicitly use the GSO library
to segment packets. To segment a packet requires two steps. The first
is to set proper flags to mbuf->ol_flags, where the flags are the same
as that of TSO. The second is to call the segmentation API,
rte_gso_segment(). This patch introduces the GSO API framework to DPDK.
rte_gso_segment() splits an input packet into small ones in each
invocation. The GSO library refers to these small packets generated
by rte_gso_segment() as GSO segments. Each of the newly-created GSO
segments is organized as a two-segment MBUF, where the first segment is a
standard MBUF, which stores a copy of packet header, and the second is an
indirect MBUF which points to a section of data in the input packet.
rte_gso_segment() reduces the refcnt of the input packet by 1. Therefore,
when all GSO segments are freed, the input packet is freed automatically.
Additionally, since each GSO segment has multiple MBUFs (i.e. 2 MBUFs),
the driver of the interface which the GSO segments are sent to should
support to transmit multi-segment packets.
The GSO framework clears the PKT_TX_TCP_SEG flag for both the input
packet, and all produced GSO segments in the event of success, since
segmentation in hardware is no longer required at that point.
Signed-off-by: Jiayu Hu <jiayu.hu@intel.com>
Signed-off-by: Mark Kavanagh <mark.b.kavanagh@intel.com>
Acked-by: Konstantin Ananyev <konstantin.ananyev@intel.com>
