[PATCH bpf-next v2 0/8] Simplify xdp_do_redirect_map()/xdp_do_flush_map() and XDP maps

Björn Töpel
2019-12-19T06:10:23Z

This series aims to simplify the XDP maps and
xdp_do_redirect_map()/xdp_do_flush_map(), and to crank out some more
performance from XDP_REDIRECT scenarios.

The first part of the series simplifies all XDP_REDIRECT capable maps,
so that __XXX_flush_map() does not require the map parameter, by
moving the flush list from the map to global scope.

This results in that the map_to_flush member can be removed from
struct bpf_redirect_info, and its corresponding logic.

Simpler code, and more performance due to that checks/code per-packet
is moved to flush.

Pre-series performance:
$ sudo taskset -c 22 ./xdpsock -i enp134s0f0 -q 20 -n 1 -r -z

sock0@enp134s0f0:20 rxdrop xdp-drv
pps pkts 1.00
rx 20,797,350 230,942,399
tx 0 0

$ sudo ./xdp_redirect_cpu --dev enp134s0f0 --cpu 22 xdp_cpu_map0

Running XDP/eBPF prog_name:xdp_cpu_map5_lb_hash_ip_pairs
XDP-cpumap CPU:to pps drop-pps extra-info
XDP-RX 20 7723038 0 0
XDP-RX total 7723038 0
cpumap_kthread total 0 0 0
redirect_err total 0 0
xdp_exception total 0 0

Post-series performance:
$ sudo taskset -c 22 ./xdpsock -i enp134s0f0 -q 20 -n 1 -r -z

sock0@enp134s0f0:20 rxdrop xdp-drv
pps pkts 1.00
rx 21,524,979 86,835,327
tx 0 0

$ sudo ./xdp_redirect_cpu --dev enp134s0f0 --cpu 22 xdp_cpu_map0

Running XDP/eBPF prog_name:xdp_cpu_map5_lb_hash_ip_pairs
XDP-cpumap CPU:to pps drop-pps extra-info
XDP-RX 20 7840124 0 0
XDP-RX total 7840124 0
cpumap_kthread total 0 0 0
redirect_err total 0 0
xdp_exception total 0 0

Results: +3.5% and +1.5% for the ubenchmarks.

v1->v2 [1]:
* Removed 'unused-variable' compiler warning (Jakub)

[1] https://lore.kernel.org/bpf/20191218105400.2895-1-bjorn.topel@gmail.com/

Björn Töpel (8):
xdp: simplify devmap cleanup
xdp: simplify cpumap cleanup
xdp: fix graze->grace type-o in cpumap comments
xsk: make xskmap flush_list common for all map instances
xdp: make devmap flush_list common for all map instances
xdp: make cpumap flush_list common for all map instances
xdp: remove map_to_flush and map swap detection
xdp: simplify __bpf_tx_xdp_map()

include/linux/bpf.h | 8 ++---
include/linux/filter.h | 1 -
include/net/xdp_sock.h | 11 +++---
kernel/bpf/cpumap.c | 76 ++++++++++++++--------------------------
kernel/bpf/devmap.c | 78 ++++++++++--------------------------------
kernel/bpf/xskmap.c | 18 ++--------
net/core/filter.c | 63 ++++++----------------------------
net/xdp/xsk.c | 17 ++++-----
8 files changed, 75 insertions(+), 197 deletions(-)

--
2.20.1