Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Jump to bottom

xdp: hints via kfuncs #3951

Closed
wants to merge 14 commits into from
Closed

xdp: hints via kfuncs #3951

wants to merge 14 commits into from

Conversation

kernel-patches-bot
Copy link

Pull request for series with
subject: xdp: hints via kfuncs
version: 2
url: https://patchwork.kernel.org/project/netdevbpf/list/?series=691908

@fomichev
bpf: Introduce bpf_patch
3f58ac9 
A simple abstraction around a series of instructions that transparently
handles resizing.

Currently, we have insn_buf[16] in convert_ctx_accesses which might
not be enough for xdp kfuncs.

If we find this abstraction helpful, we might convert existing
insn_buf[16] to it in the future.

Cc: John Fastabend <john.fastabend@gmail.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Martin KaFai Lau <martin.lau@linux.dev>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Willem de Bruijn <willemb@google.com>
Cc: Jesper Dangaard Brouer <brouer@redhat.com>
Cc: Anatoly Burakov <anatoly.burakov@intel.com>
Cc: Alexander Lobakin <alexandr.lobakin@intel.com>
Cc: Magnus Karlsson <magnus.karlsson@gmail.com>
Cc: Maryam Tahhan <mtahhan@redhat.com>
Cc: xdp-hints@xdp-project.net
Cc: netdev@vger.kernel.org
Signed-off-by: Stanislav Fomichev <sdf@google.com>
@fomichev
bpf: Support inlined/unrolled kfuncs for xdp metadata
5b037e7 
Kfuncs have to be defined with KF_UNROLL for an attempted unroll.
For now, only XDP programs can have their kfuncs unrolled, but
we can extend this later on if more programs would like to use it.

For XDP, we define a new kfunc set (xdp_metadata_kfunc_ids) which
implements all possible metatada kfuncs. Not all devices have to
implement them. If unrolling is not supported by the target device,
the default implementation is called instead. The default
implementation is unconditionally unrolled to 'return false/0/NULL'
for now.

Upon loading, if BPF_F_XDP_HAS_METADATA is passed via prog_flags,
we treat prog_index as target device for kfunc unrolling.
net_device_ops gains new ndo_unroll_kfunc which does the actual
dirty work per device.

The kfunc unrolling itself largely follows the existing map_gen_lookup
unrolling example, so there is nothing new here.

Cc: John Fastabend <john.fastabend@gmail.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Martin KaFai Lau <martin.lau@linux.dev>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Willem de Bruijn <willemb@google.com>
Cc: Jesper Dangaard Brouer <brouer@redhat.com>
Cc: Anatoly Burakov <anatoly.burakov@intel.com>
Cc: Alexander Lobakin <alexandr.lobakin@intel.com>
Cc: Magnus Karlsson <magnus.karlsson@gmail.com>
Cc: Maryam Tahhan <mtahhan@redhat.com>
Cc: xdp-hints@xdp-project.net
Cc: netdev@vger.kernel.org
Signed-off-by: Stanislav Fomichev <sdf@google.com>
@fomichev
veth: Introduce veth_xdp_buff wrapper for xdp_buff
2c4185c 
No functional changes. Boilerplate to allow stuffing more data after xdp_buff.

Cc: John Fastabend <john.fastabend@gmail.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Martin KaFai Lau <martin.lau@linux.dev>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Willem de Bruijn <willemb@google.com>
Cc: Jesper Dangaard Brouer <brouer@redhat.com>
Cc: Anatoly Burakov <anatoly.burakov@intel.com>
Cc: Alexander Lobakin <alexandr.lobakin@intel.com>
Cc: Magnus Karlsson <magnus.karlsson@gmail.com>
Cc: Maryam Tahhan <mtahhan@redhat.com>
Cc: xdp-hints@xdp-project.net
Cc: netdev@vger.kernel.org
Signed-off-by: Stanislav Fomichev <sdf@google.com>
@fomichev
veth: Support rx timestamp metadata for xdp
9187887 
xskxceiver conveniently setups up veth pairs so it seems logical
to use veth as an example for some of the metadata handling.

We timestamp skb right when we "receive" it, store its
pointer in new veth_xdp_buff wrapper and generate BPF bytecode to
reach it from the BPF program.

This largely follows the idea of "store some queue context in
the xdp_buff/xdp_frame so the metadata can be reached out
from the BPF program".

Cc: John Fastabend <john.fastabend@gmail.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Martin KaFai Lau <martin.lau@linux.dev>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Willem de Bruijn <willemb@google.com>
Cc: Jesper Dangaard Brouer <brouer@redhat.com>
Cc: Anatoly Burakov <anatoly.burakov@intel.com>
Cc: Alexander Lobakin <alexandr.lobakin@intel.com>
Cc: Magnus Karlsson <magnus.karlsson@gmail.com>
Cc: Maryam Tahhan <mtahhan@redhat.com>
Cc: xdp-hints@xdp-project.net
Cc: netdev@vger.kernel.org
Signed-off-by: Stanislav Fomichev <sdf@google.com>
@fomichev
selftests/bpf: Verify xdp_metadata xdp->af_xdp path
1fe7cac 
- create new netns
- create veth pair (veTX+veRX)
- setup AF_XDP socket for both interfaces
- attach bpf to veRX
- send packet via veTX
- verify the packet has expected metadata at veRX

Cc: John Fastabend <john.fastabend@gmail.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Martin KaFai Lau <martin.lau@linux.dev>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Willem de Bruijn <willemb@google.com>
Cc: Jesper Dangaard Brouer <brouer@redhat.com>
Cc: Anatoly Burakov <anatoly.burakov@intel.com>
Cc: Alexander Lobakin <alexandr.lobakin@intel.com>
Cc: Magnus Karlsson <magnus.karlsson@gmail.com>
Cc: Maryam Tahhan <mtahhan@redhat.com>
Cc: xdp-hints@xdp-project.net
Cc: netdev@vger.kernel.org
Signed-off-by: Stanislav Fomichev <sdf@google.com>
@fomichev
xdp: Carry over xdp metadata into skb context
58a51a9 
Implement new bpf_xdp_metadata_export_to_skb kfunc which
prepares compatible xdp metadata for kernel consumption.
This kfunc should be called prior to bpf_redirect
or (unless already called) when XDP_PASS'ing the frame
into the kernel.

The implementation currently maintains xdp_to_skb_metadata
layout by calling bpf_xdp_metadata_rx_timestamp and placing
small magic number. From skb_metdata_set, when we get expected magic number,
we interpret metadata accordingly.

Both magic number and struct layout are randomized to make sure
it doesn't leak into the userspace.

skb_metadata_set is amended with skb_metadata_import_from_xdp which
tries to parse out the metadata and put it into skb.

See the comment for r1 vs r2/r3/r4/r5 conventions.

Cc: John Fastabend <john.fastabend@gmail.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Martin KaFai Lau <martin.lau@linux.dev>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Willem de Bruijn <willemb@google.com>
Cc: Jesper Dangaard Brouer <brouer@redhat.com>
Cc: Anatoly Burakov <anatoly.burakov@intel.com>
Cc: Alexander Lobakin <alexandr.lobakin@intel.com>
Cc: Magnus Karlsson <magnus.karlsson@gmail.com>
Cc: Maryam Tahhan <mtahhan@redhat.com>
Cc: xdp-hints@xdp-project.net
Cc: netdev@vger.kernel.org
Signed-off-by: Stanislav Fomichev <sdf@google.com>
@fomichev
selftests/bpf: Verify xdp_metadata xdp->skb path
2823ac7 
- divert 9081 UDP traffic to the kernel
- call bpf_xdp_metadata_export_to_skb for such packets
- the kernel should fill in hwtstamp
- verify that the received packet has non-zero hwtstamp

Cc: John Fastabend <john.fastabend@gmail.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Martin KaFai Lau <martin.lau@linux.dev>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Willem de Bruijn <willemb@google.com>
Cc: Jesper Dangaard Brouer <brouer@redhat.com>
Cc: Anatoly Burakov <anatoly.burakov@intel.com>
Cc: Alexander Lobakin <alexandr.lobakin@intel.com>
Cc: Magnus Karlsson <magnus.karlsson@gmail.com>
Cc: Maryam Tahhan <mtahhan@redhat.com>
Cc: xdp-hints@xdp-project.net
Cc: netdev@vger.kernel.org
Signed-off-by: Stanislav Fomichev <sdf@google.com>
@fomichev
bpf: Helper to simplify calling kernel routines from unrolled kfuncs
fa5f202 
When we need to call the kernel function from the unrolled
kfunc, we have to take extra care: r6-r9 belong to the callee,
not us, so we can't use these registers to stash our r1.

We use the same trick we use elsewhere: ask the user
to provide extra on-stack storage.

Also, note, the program being called has to receive and
return the context.

Cc: John Fastabend <john.fastabend@gmail.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Martin KaFai Lau <martin.lau@linux.dev>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Willem de Bruijn <willemb@google.com>
Cc: Jesper Dangaard Brouer <brouer@redhat.com>
Cc: Anatoly Burakov <anatoly.burakov@intel.com>
Cc: Alexander Lobakin <alexandr.lobakin@intel.com>
Cc: Magnus Karlsson <magnus.karlsson@gmail.com>
Cc: Maryam Tahhan <mtahhan@redhat.com>
Cc: xdp-hints@xdp-project.net
Cc: netdev@vger.kernel.org
Signed-off-by: Stanislav Fomichev <sdf@google.com>
@fomichev
ice: Introduce ice_xdp_buff wrapper for xdp_buff
19c3243 
No functional changes. Boilerplate to allow stuffing more data after xdp_buff.

Cc: John Fastabend <john.fastabend@gmail.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Martin KaFai Lau <martin.lau@linux.dev>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Willem de Bruijn <willemb@google.com>
Cc: Jesper Dangaard Brouer <brouer@redhat.com>
Cc: Anatoly Burakov <anatoly.burakov@intel.com>
Cc: Alexander Lobakin <alexandr.lobakin@intel.com>
Cc: Magnus Karlsson <magnus.karlsson@gmail.com>
Cc: Maryam Tahhan <mtahhan@redhat.com>
Cc: xdp-hints@xdp-project.net
Cc: netdev@vger.kernel.org
Signed-off-by: Stanislav Fomichev <sdf@google.com>
@fomichev
ice: Support rx timestamp metadata for xdp
b427348 
COMPILE-TESTED ONLY!

Cc: John Fastabend <john.fastabend@gmail.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Martin KaFai Lau <martin.lau@linux.dev>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Willem de Bruijn <willemb@google.com>
Cc: Jesper Dangaard Brouer <brouer@redhat.com>
Cc: Anatoly Burakov <anatoly.burakov@intel.com>
Cc: Alexander Lobakin <alexandr.lobakin@intel.com>
Cc: Magnus Karlsson <magnus.karlsson@gmail.com>
Cc: Maryam Tahhan <mtahhan@redhat.com>
Cc: xdp-hints@xdp-project.net
Cc: netdev@vger.kernel.org
Signed-off-by: Stanislav Fomichev <sdf@google.com>
@fomichev
mlx4: Introduce mlx4_xdp_buff wrapper for xdp_buff
fc84b72 
No functional changes. Boilerplate to allow stuffing more data after xdp_buff.

Cc: John Fastabend <john.fastabend@gmail.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Martin KaFai Lau <martin.lau@linux.dev>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Willem de Bruijn <willemb@google.com>
Cc: Jesper Dangaard Brouer <brouer@redhat.com>
Cc: Anatoly Burakov <anatoly.burakov@intel.com>
Cc: Alexander Lobakin <alexandr.lobakin@intel.com>
Cc: Magnus Karlsson <magnus.karlsson@gmail.com>
Cc: Maryam Tahhan <mtahhan@redhat.com>
Cc: xdp-hints@xdp-project.net
Cc: netdev@vger.kernel.org
Signed-off-by: Stanislav Fomichev <sdf@google.com>
@fomichev
mxl4: Support rx timestamp metadata for xdp
475916f 
COMPILE-TESTED ONLY!

Cc: John Fastabend <john.fastabend@gmail.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Martin KaFai Lau <martin.lau@linux.dev>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Willem de Bruijn <willemb@google.com>
Cc: Jesper Dangaard Brouer <brouer@redhat.com>
Cc: Anatoly Burakov <anatoly.burakov@intel.com>
Cc: Alexander Lobakin <alexandr.lobakin@intel.com>
Cc: Magnus Karlsson <magnus.karlsson@gmail.com>
Cc: Maryam Tahhan <mtahhan@redhat.com>
Cc: xdp-hints@xdp-project.net
Cc: netdev@vger.kernel.org
Signed-off-by: Stanislav Fomichev <sdf@google.com>
@fomichev
bnxt: Introduce bnxt_xdp_buff wrapper for xdp_buff
2068faa 
No functional changes. Boilerplate to allow stuffing more data after xdp_buff.

Cc: John Fastabend <john.fastabend@gmail.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Martin KaFai Lau <martin.lau@linux.dev>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Willem de Bruijn <willemb@google.com>
Cc: Jesper Dangaard Brouer <brouer@redhat.com>
Cc: Anatoly Burakov <anatoly.burakov@intel.com>
Cc: Alexander Lobakin <alexandr.lobakin@intel.com>
Cc: Magnus Karlsson <magnus.karlsson@gmail.com>
Cc: Maryam Tahhan <mtahhan@redhat.com>
Cc: xdp-hints@xdp-project.net
Cc: netdev@vger.kernel.org
Signed-off-by: Stanislav Fomichev <sdf@google.com>
@fomichev
bnxt: Support rx timestamp metadata for xdp
f69c5b6 
COMPILE-TESTED ONLY!

Cc: John Fastabend <john.fastabend@gmail.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Martin KaFai Lau <martin.lau@linux.dev>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Willem de Bruijn <willemb@google.com>
Cc: Jesper Dangaard Brouer <brouer@redhat.com>
Cc: Anatoly Burakov <anatoly.burakov@intel.com>
Cc: Alexander Lobakin <alexandr.lobakin@intel.com>
Cc: Magnus Karlsson <magnus.karlsson@gmail.com>
Cc: Maryam Tahhan <mtahhan@redhat.com>
Cc: xdp-hints@xdp-project.net
Cc: netdev@vger.kernel.org
Signed-off-by: Stanislav Fomichev <sdf@google.com>
@kernel-patches-bot
Copy link
Author

Upstream branch: 07ec7b5
series: https://patchwork.kernel.org/project/netdevbpf/list/?series=691908
version: 2

@kernel-patches-bot
Copy link
Author

At least one diff in series https://patchwork.kernel.org/project/netdevbpf/list/?series=691908 expired. Closing PR.

@kernel-patches-bot kernel-patches-bot deleted the series/689566=>bpf-next branch November 6, 2022 11:30
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
Reviewers
No reviews
Assignees
No one assigned
Labels
bpf-next rfc V2
Projects
None yet
Milestone
No milestone
2 participants
@kernel-patches-bot @fomichev