Hi XDP-folks,
This two patch series contain two optimizations for the
bpf_redirect_map() helper and the xdp_do_redirect() function.
The bpf_redirect_map() optimization is about avoiding the map lookup
dispatching. Instead of having a switch-statement and selecting the
correct lookup function, we let bpf_redirect_map() be a map operation,
where each map has its own bpf_redirect_map() implementation. This way
the run-time lookup is avoided.
The xdp_do_redirect() patch restructures the code, so that the map
pointer indirection can be avoided.
Performance-wise I got 4% improvement for XSKMAP
(sample:xdpsock/rx-drop), and 8% (sample:xdp_redirect_map) on my
machine.
@Jesper/@Toke I kept your Acked-by: for patch 2. Let me know, if you
don't agree with that decision.
More details in each commit.
Changelog:
v5->v6: Removed REDIR enum, and instead use map_id and map_type. (Daniel)
Applied Daniel's fixups on patch 1. (Daniel)
v4->v5: Renamed map operation to map_redirect. (Daniel)
v3->v4: Made bpf_redirect_map() a map operation. (Daniel)
v2->v3: Fix build when CONFIG_NET is not set. (lkp)
v1->v2: Removed warning when CONFIG_BPF_SYSCALL was not set. (lkp)
Cleaned up case-clause in xdp_do_generic_redirect_map(). (Toke)
Re-added comment. (Toke)
rfc->v1: Use map_id, and remove bpf_clear_redirect_map(). (Toke)
Get rid of the macro and use __always_inline. (Jesper)
rfc: https://lore.kernel.org/bpf/87im7fy9nc.fsf@xxxxxxx/ (Cover not on lore!)
v1: https://lore.kernel.org/bpf/20210219145922.63655-1-bjorn.topel@xxxxxxxxx/
v2: https://lore.kernel.org/bpf/20210220153056.111968-1-bjorn.topel@xxxxxxxxx/
v3: https://lore.kernel.org/bpf/20210221200954.164125-3-bjorn.topel@xxxxxxxxx/
v4: https://lore.kernel.org/bpf/20210226112322.144927-1-bjorn.topel@xxxxxxxxx/
v5: https://lore.kernel.org/bpf/20210227122139.183284-1-bjorn.topel@xxxxxxxxx/
Björn Töpel (2):
bpf, xdp: make bpf_redirect_map() a map operation
bpf, xdp: restructure redirect actions
include/linux/bpf.h | 26 ++---
include/linux/filter.h | 31 +++++-
include/net/xdp_sock.h | 19 ----
include/trace/events/xdp.h | 62 ++++++-----
kernel/bpf/cpumap.c | 9 +-
kernel/bpf/devmap.c | 17 ++-
kernel/bpf/verifier.c | 13 ++-
net/core/filter.c | 209 ++++++++++++++-----------------------
net/xdp/xskmap.c | 17 ++-
9 files changed, 195 insertions(+), 208 deletions(-)
base-commit: 5e6d87315279db3abe69e2ebfd05fa8f5c014295
--
2.27.0
