All of lore.kernel.org
 help / color / mirror / Atom feed
* [bpf-next V1-RFC PATCH 00/14] xdp: new XDP rx-queue info concept
@ 2017-12-13 11:19 Jesper Dangaard Brouer
  2017-12-13 11:19 ` [bpf-next V1-RFC PATCH 01/14] xdp: base API for " Jesper Dangaard Brouer
                   ` (13 more replies)
  0 siblings, 14 replies; 39+ messages in thread
From: Jesper Dangaard Brouer @ 2017-12-13 11:19 UTC (permalink / raw)
  To: Daniel Borkmann, Alexei Starovoitov
  Cc: netdev, Jesper Dangaard Brouer, dsahern, gospo, bjorn.topel,
	michael.chan

NOTICE: I send this as RFC to give driver developers a heads-up,
        while I complete the testing of the drivers (which I have HW for).
        I don't expect many changes before I post it officially.

There is a need for XDP to know more about the RX-queue a given XDP
frames have arrived on.  For both the XDP bpf-prog and kernel side.

Instead of extending struct xdp_buff each time new info is needed,
this patchset takes a different approach.  Struct xdp_buff is only
extended with a pointer to a struct xdp_rxq_info (allowing for easier
extending this later).  This xdp_rxq_info contains information related
to how the driver have setup the individual RX-queue's.  This is
read-mostly information, and all xdp_buff frames (in drivers
napi_poll) point to the same xdp_rxq_info (per RX-queue).

We stress this data/cache-line is for read-mostly info.  This is NOT
for dynamic per packet info, use the data_meta for such use-cases.

This patchset start out small, and only expose ingress_ifindex and the
RX queue index to the XDP/BPF program. Access to tangible info like
the ingress ifindex and RX queue index, is fairly easy to comprehent.
The other future use-cases could allow XDP frames to be recycled back
to the originating device driver, by providing info on RX device and
queue number.

As XDP doesn't have driver feature flags, and eBPF code due to
bpf-tail-calls cannot determine that XDP driver invoke it, this
patchset have to update every driver that support XDP.

For driver developers (review individual driver patches!):

The xdp_rxq_info is tied to the drivers RX-ring(s). Whenever a RX-ring
modification require (temporary) stopping RX frames, then the
xdp_rxq_info should (likely) also be unregistred and re-registered,
especially if reallocating the pages in the ring. Make sure ethtool
set_channels does the right thing. When replacing XDP prog, if and
only if RX-ring need to be changed, then also re-register the
xdp_rxq_info.

I'm Cc'ing the individual driver patches to the registered maintainers.

Testing:

I've only tested the NIC drivers I have hardware for.  The general
test procedure is to (DUT = Device Under Test):
 (1) run pktgen script pktgen_sample04_many_flows.sh (against DUT),
 (2) run samples/bpf program xdp_rxq_info --dev $DEV (on DUT)
 (3) runtime modify NIC queue via ethtool -L (on DUT)

RFC notes/questions:

(A) Didn't update driver netdevsim, as it doesn't reference xdp_buff.

(B) Must I write a test for tools/testing/selftests/bpf/ ?

(C) The bnxt_en driver should re-register when changing ring layout

(D) Should xdp_rxq_info be SLAB allocated instead of embedding into drv structs?

(E) Should struct be named xdp_info instead for future (e.g TX) use-cases?

Patch based on git tree bpf-next (at commit 553a8f2f42):
 https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next.git/

---

Jesper Dangaard Brouer (14):
      xdp: base API for new XDP rx-queue info concept
      xdp/mlx5: setup xdp_rxq_info and extend with qtype
      i40e: setup xdp_rxq_info
      ixgbe: setup xdp_rxq_info
      xdp/qede: setup xdp_rxq_info and intro xdp_rxq_info_is_reg
      mlx4: setup xdp_rxq_info
      bnxt_en: setup xdp_rxq_info
      nfp: setup xdp_rxq_info
      thunderx: setup xdp_rxq_info
      tun: setup xdp_rxq_info
      virtio_net: setup xdp_rxq_info
      xdp: generic XDP handling of xdp_rxq_info
      bpf: finally expose xdp_rxq_info to XDP bpf-programs
      samples/bpf: program demonstrating access to xdp_rxq_info


 drivers/net/ethernet/broadcom/bnxt/bnxt.c          |   10 
 drivers/net/ethernet/broadcom/bnxt/bnxt.h          |    2 
 drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c      |    1 
 drivers/net/ethernet/cavium/thunder/nicvf_main.c   |   11 
 drivers/net/ethernet/cavium/thunder/nicvf_queues.c |    7 
 drivers/net/ethernet/cavium/thunder/nicvf_queues.h |    2 
 drivers/net/ethernet/intel/i40e/i40e_txrx.c        |   18 +
 drivers/net/ethernet/intel/i40e/i40e_txrx.h        |    3 
 drivers/net/ethernet/intel/ixgbe/ixgbe.h           |    2 
 drivers/net/ethernet/intel/ixgbe/ixgbe_main.c      |   11 
 drivers/net/ethernet/mellanox/mlx4/en_netdev.c     |    3 
 drivers/net/ethernet/mellanox/mlx4/en_rx.c         |   13 
 drivers/net/ethernet/mellanox/mlx4/mlx4_en.h       |    4 
 drivers/net/ethernet/mellanox/mlx5/core/en.h       |    4 
 drivers/net/ethernet/mellanox/mlx5/core/en_main.c  |   14 +
 drivers/net/ethernet/mellanox/mlx5/core/en_rx.c    |    1 
 drivers/net/ethernet/netronome/nfp/nfp_net.h       |    5 
 .../net/ethernet/netronome/nfp/nfp_net_common.c    |   10 
 drivers/net/ethernet/qlogic/qede/qede.h            |    2 
 drivers/net/ethernet/qlogic/qede/qede_fp.c         |    1 
 drivers/net/ethernet/qlogic/qede/qede_main.c       |   12 
 drivers/net/tun.c                                  |   25 +
 drivers/net/virtio_net.c                           |   12 
 include/linux/filter.h                             |    2 
 include/linux/netdevice.h                          |    2 
 include/net/xdp.h                                  |   69 +++
 include/uapi/linux/bpf.h                           |    3 
 net/core/Makefile                                  |    2 
 net/core/dev.c                                     |   60 ++
 net/core/filter.c                                  |   19 +
 net/core/xdp.c                                     |   57 ++
 samples/bpf/Makefile                               |    4 
 samples/bpf/xdp_rxq_info_kern.c                    |   96 ++++
 samples/bpf/xdp_rxq_info_user.c                    |  533 ++++++++++++++++++++
 34 files changed, 996 insertions(+), 24 deletions(-)
 create mode 100644 include/net/xdp.h
 create mode 100644 net/core/xdp.c
 create mode 100644 samples/bpf/xdp_rxq_info_kern.c
 create mode 100644 samples/bpf/xdp_rxq_info_user.c

^ permalink raw reply	[flat|nested] 39+ messages in thread

end of thread, other threads:[~2017-12-21 16:59 UTC | newest]

Thread overview: 39+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2017-12-13 11:19 [bpf-next V1-RFC PATCH 00/14] xdp: new XDP rx-queue info concept Jesper Dangaard Brouer
2017-12-13 11:19 ` [bpf-next V1-RFC PATCH 01/14] xdp: base API for " Jesper Dangaard Brouer
2017-12-14  2:34   ` David Ahern
2017-12-18 10:55     ` Jesper Dangaard Brouer
2017-12-18 13:23       ` David Ahern
2017-12-18 15:52         ` Jesper Dangaard Brouer
2017-12-21 16:59       ` Jesper Dangaard Brouer
2017-12-13 11:19 ` [bpf-next V1-RFC PATCH 02/14] xdp/mlx5: setup xdp_rxq_info and extend with qtype Jesper Dangaard Brouer
2017-12-13 12:27   ` Tariq Toukan
2017-12-13 13:44     ` Jesper Dangaard Brouer
2017-12-13 23:03       ` Saeed Mahameed
2017-12-14  6:46         ` Jesper Dangaard Brouer
2017-12-13 11:19 ` [bpf-next V1-RFC PATCH 03/14] i40e: setup xdp_rxq_info Jesper Dangaard Brouer
2017-12-13 11:19   ` [Intel-wired-lan] " Jesper Dangaard Brouer
2017-12-18 10:52   ` Björn Töpel
2017-12-18 10:52     ` =?unknown-8bit?q?Bj=C3=B6rn_T=C3=B6pel?=
2017-12-18 13:05     ` Jesper Dangaard Brouer
2017-12-18 13:05       ` Jesper Dangaard Brouer
2017-12-13 11:19 ` [bpf-next V1-RFC PATCH 04/14] ixgbe: " Jesper Dangaard Brouer
2017-12-13 11:19   ` [Intel-wired-lan] " Jesper Dangaard Brouer
2017-12-13 11:19 ` [bpf-next V1-RFC PATCH 05/14] xdp/qede: setup xdp_rxq_info and intro xdp_rxq_info_is_reg Jesper Dangaard Brouer
2017-12-13 11:19 ` [bpf-next V1-RFC PATCH 06/14] mlx4: setup xdp_rxq_info Jesper Dangaard Brouer
2017-12-13 12:42   ` Tariq Toukan
2017-12-13 14:00     ` Jesper Dangaard Brouer
2017-12-13 11:19 ` [bpf-next V1-RFC PATCH 07/14] bnxt_en: " Jesper Dangaard Brouer
2017-12-13 11:20 ` [bpf-next V1-RFC PATCH 08/14] nfp: " Jesper Dangaard Brouer
2017-12-14  2:34   ` Jakub Kicinski
2017-12-18 20:25     ` Jesper Dangaard Brouer
2017-12-13 11:20 ` [bpf-next V1-RFC PATCH 09/14] thunderx: " Jesper Dangaard Brouer
2017-12-13 11:20   ` Jesper Dangaard Brouer
2017-12-13 11:20 ` [bpf-next V1-RFC PATCH 10/14] tun: " Jesper Dangaard Brouer
2017-12-20  7:48   ` Jason Wang
2017-12-21 15:42     ` Jesper Dangaard Brouer
2017-12-13 11:20 ` [bpf-next V1-RFC PATCH 11/14] virtio_net: " Jesper Dangaard Brouer
2017-12-13 11:20 ` [bpf-next V1-RFC PATCH 12/14] xdp: generic XDP handling of xdp_rxq_info Jesper Dangaard Brouer
2017-12-13 22:50   ` Saeed Mahameed
2017-12-18  9:47     ` Jesper Dangaard Brouer
2017-12-13 11:20 ` [bpf-next V1-RFC PATCH 13/14] bpf: finally expose xdp_rxq_info to XDP bpf-programs Jesper Dangaard Brouer
2017-12-13 11:20 ` [bpf-next V1-RFC PATCH 14/14] samples/bpf: program demonstrating access to xdp_rxq_info Jesper Dangaard Brouer

This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.