On Sun, 21 Feb 2021 21:09:54 +0100 Björn Töpel <bjorn.topel@xxxxxxxxx> wrote: > From: Björn Töpel <bjorn.topel@xxxxxxxxx> > > The XDP_REDIRECT implementations for maps and non-maps are fairly > similar, but obviously need to take different code paths depending on > if the target is using a map or not. Today, the redirect targets for > XDP either uses a map, or is based on ifindex. > > Here, an explicit redirect type is added to bpf_redirect_info, instead > of the actual map. Redirect type, map item/ifindex, and the map_id (if > any) is passed to xdp_do_redirect(). > > In addition to making the code easier to follow, using an explicit > type in bpf_redirect_info has a slight positive performance impact by > avoiding a pointer indirection for the map type lookup, and instead > use the cacheline for bpf_redirect_info. > > Since the actual map is not passed via bpf_redirect_info anymore, the > map lookup is only done in the BPF helper. This means that the > bpf_clear_redirect_map() function can be removed. The actual map item > is RCU protected. > > The bpf_redirect_info flags member is not used by XDP, and not > read/written any more. The map member is only written to when > required/used, and not unconditionally. > > v1->v2 : Removed warning when CONFIG_BPF_SYSCALL was not set. (lkp) > : Cleaned up case-clause in xdp_do_generic_redirect_map(). (Toke) > rfc->v1: Use map_id, and remove bpf_clear_redirect_map(). (Toke) > > Acked-by: Toke Høiland-Jørgensen <toke@xxxxxxxxxx> > Reviewed-by: Maciej Fijalkowski <maciej.fijalkowski@xxxxxxxxx> > Signed-off-by: Björn Töpel <bjorn.topel@xxxxxxxxx> > --- > include/linux/bpf.h | 1 + > include/linux/filter.h | 11 ++- > include/trace/events/xdp.h | 66 +++++++++------ > kernel/bpf/cpumap.c | 1 - > kernel/bpf/devmap.c | 1 - > net/core/filter.c | 165 ++++++++++++++++--------------------- > net/xdp/xskmap.c | 1 - > 7 files changed, 122 insertions(+), 124 deletions(-) I like it! :-) Acked-by: Jesper Dangaard Brouer <brouer@xxxxxxxxxx> -- Best regards, Jesper Dangaard Brouer MSc.CS, Principal Kernel Engineer at Red Hat LinkedIn: http://www.linkedin.com/in/brouer
