[PATCH net-next v8 0/3] net: gro: remove network_header use, move p->{flush/flush_id} calculations to L4

From: Richard Gobert
Date: Mon May 06 2024 - 05:37:09 EST


The cb fields network_offset and inner_network_offset are used instead of
skb->network_header throughout GRO.

These fields are then leveraged in the next commit to remove flush_id state
from napi_gro_cb, and stateful code in {ipv6,inet}_gro_receive which may be
unnecessarily complicated due to encapsulation support in GRO. These fields
are checked in L4 instead.

3rd patch adds tests for different flush_id flows in GRO.

v7 -> v8:
- Remove network_header use in gro
- Re-send commits after the dependent patch to net was applied
- v7:
https://lore.kernel.org/all/20240412155533.115507-1-richardbgobert@xxxxxxxxx/

v6 -> v7:
- Moved bug fixes to a separate submission in net
- Added UDP fwd benchmark
- v6:
https://lore.kernel.org/all/20240410153423.107381-1-richardbgobert@xxxxxxxxx/

v5 -> v6:
- Write inner_network_offset in vxlan and geneve
- Ignore is_atomic when DF=0
- v5:
https://lore.kernel.org/all/20240408141720.98832-1-richardbgobert@xxxxxxxxx/

v4 -> v5:
- Add 1st commit - flush id checks in udp_gro_receive segment which can be
backported by itself
- Add TCP measurements for the 5th commit
- Add flush id tests to ensure flush id logic is preserved in GRO
- Simplify gro_inet_flush by removing a branch
- v4:
https://lore.kernel.org/all/202420325182543.87683-1-richardbgobert@xxxxxxxxx/

v3 -> v4:
- Fix code comment and commit message typos
- v3:
https://lore.kernel.org/all/f939c84a-2322-4393-a5b0-9b1e0be8ed8e@xxxxxxxxx/

v2 -> v3:
- Use napi_gro_cb instead of skb->{offset}
- v2:
https://lore.kernel.org/all/2ce1600b-e733-448b-91ac-9d0ae2b866a4@xxxxxxxxx/

v1 -> v2:
- Pass p_off in *_gro_complete to fix UDP bug
- Remove more conditionals and memory fetches from inet_gro_flush
- v1:
https://lore.kernel.org/netdev/e1d22505-c5f8-4c02-a997-64248480338b@xxxxxxxxx/

Richard Gobert (3):
net: gro: use cb instead of skb->network_header
net: gro: move L3 flush checks to tcp_gro_receive and udp_gro_receive_segment
selftests/net: add flush id selftests

include/net/gro.h | 75 +++++++++++++--
net/core/gro.c | 3 -
net/ipv4/af_inet.c | 45 +--------
net/ipv4/tcp_offload.c | 18 +---
net/ipv4/udp_offload.c | 10 +-
net/ipv6/ip6_offload.c | 16 +---
net/ipv6/tcpv6_offload.c | 3 +-
tools/testing/selftests/net/gro.c | 147 ++++++++++++++++++++++++++++++
8 files changed, 225 insertions(+), 92 deletions(-)

--
2.36.1