XDP hardware hints discussion mail archive
 help / color / mirror / Atom feed
From: Stanislav Fomichev <sdf@google.com>
To: bpf@vger.kernel.org
Cc: ast@kernel.org, daniel@iogearbox.net, andrii@kernel.org,
	martin.lau@linux.dev, song@kernel.org, yhs@fb.com,
	john.fastabend@gmail.com, kpsingh@kernel.org, sdf@google.com,
	haoluo@google.com, jolsa@kernel.org,
	Jakub Kicinski <kuba@kernel.org>,
	Willem de Bruijn <willemb@google.com>,
	Jesper Dangaard Brouer <brouer@redhat.com>,
	Anatoly Burakov <anatoly.burakov@intel.com>,
	Alexander Lobakin <alexandr.lobakin@intel.com>,
	Magnus Karlsson <magnus.karlsson@gmail.com>,
	Maryam Tahhan <mtahhan@redhat.com>,
	xdp-hints@xdp-project.net, netdev@vger.kernel.org
Subject: [xdp-hints] [RFC bpf-next 5/5] selftests/bpf: Test rx_timestamp metadata in xskxceiver
Date: Thu, 27 Oct 2022 13:00:19 -0700	[thread overview]
Message-ID: <20221027200019.4106375-6-sdf@google.com> (raw)
In-Reply-To: <20221027200019.4106375-1-sdf@google.com>

Example on how the metadata is prepared from the BPF context
and consumed by AF_XDP:

- bpf_xdp_metadata_have_rx_timestamp to test whether it's supported;
  if not, I'm assuming verifier will remove this "if (0)" branch
- bpf_xdp_metadata_rx_timestamp returns a _copy_ of metadata;
  the program has to bpf_xdp_adjust_meta+memcpy it;
  maybe returning a pointer is better?
- af_xdp consumer grabs it from data-<expected_metadata_offset> and
  makes sure timestamp is not empty
- when loading the program, we pass BPF_F_XDP_HAS_METADATA+prog_ifindex

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>
---
 .../testing/selftests/bpf/progs/xskxceiver.c  | 22 ++++++++++++++++++
 tools/testing/selftests/bpf/xskxceiver.c      | 23 ++++++++++++++++++-
 2 files changed, 44 insertions(+), 1 deletion(-)

diff --git a/tools/testing/selftests/bpf/progs/xskxceiver.c b/tools/testing/selftests/bpf/progs/xskxceiver.c
index b135daddad3a..83c879aa3581 100644
--- a/tools/testing/selftests/bpf/progs/xskxceiver.c
+++ b/tools/testing/selftests/bpf/progs/xskxceiver.c
@@ -12,9 +12,31 @@ struct {
 	__type(value, __u32);
 } xsk SEC(".maps");
 
+extern int bpf_xdp_metadata_have_rx_timestamp(struct xdp_md *ctx) __ksym;
+extern __u32 bpf_xdp_metadata_rx_timestamp(struct xdp_md *ctx) __ksym;
+
 SEC("xdp")
 int rx(struct xdp_md *ctx)
 {
+	void *data, *data_meta;
+	__u32 rx_timestamp;
+	int ret;
+
+	if (bpf_xdp_metadata_have_rx_timestamp(ctx)) {
+		ret = bpf_xdp_adjust_meta(ctx, -(int)sizeof(__u32));
+		if (ret != 0)
+			return XDP_DROP;
+
+		data = (void *)(long)ctx->data;
+		data_meta = (void *)(long)ctx->data_meta;
+
+		if (data_meta + sizeof(__u32) > data)
+			return XDP_DROP;
+
+		rx_timestamp = bpf_xdp_metadata_rx_timestamp(ctx);
+		__builtin_memcpy(data_meta, &rx_timestamp, sizeof(__u32));
+	}
+
 	return bpf_redirect_map(&xsk, ctx->rx_queue_index, XDP_PASS);
 }
 
diff --git a/tools/testing/selftests/bpf/xskxceiver.c b/tools/testing/selftests/bpf/xskxceiver.c
index 066bd691db13..ce82c89a432e 100644
--- a/tools/testing/selftests/bpf/xskxceiver.c
+++ b/tools/testing/selftests/bpf/xskxceiver.c
@@ -871,7 +871,9 @@ static bool is_offset_correct(struct xsk_umem_info *umem, struct pkt_stream *pkt
 static bool is_pkt_valid(struct pkt *pkt, void *buffer, u64 addr, u32 len)
 {
 	void *data = xsk_umem__get_data(buffer, addr);
+	void *data_meta = data - sizeof(__u32);
 	struct iphdr *iphdr = (struct iphdr *)(data + sizeof(struct ethhdr));
+	__u32 rx_timestamp = 0;
 
 	if (!pkt) {
 		ksft_print_msg("[%s] too many packets received\n", __func__);
@@ -907,6 +909,13 @@ static bool is_pkt_valid(struct pkt *pkt, void *buffer, u64 addr, u32 len)
 		return false;
 	}
 
+	memcpy(&rx_timestamp, data_meta, sizeof(rx_timestamp));
+	if (rx_timestamp == 0) {
+		ksft_print_msg("Invalid metadata received: ");
+		ksft_print_msg("got %08x, expected != 0\n", rx_timestamp);
+		return false;
+	}
+
 	return true;
 }
 
@@ -1331,6 +1340,7 @@ static void thread_common_ops(struct test_spec *test, struct ifobject *ifobject)
 	u64 umem_sz = ifobject->umem->num_frames * ifobject->umem->frame_size;
 	int mmap_flags = MAP_PRIVATE | MAP_ANONYMOUS | MAP_NORESERVE;
 	LIBBPF_OPTS(bpf_xdp_query_opts, opts);
+	LIBBPF_OPTS(bpf_object_open_opts, open_opts);
 	int ret, ifindex;
 	void *bufs;
 
@@ -1340,10 +1350,21 @@ static void thread_common_ops(struct test_spec *test, struct ifobject *ifobject)
 	if (!ifindex)
 		exit_with_error(errno);
 
-	ifobject->bpf_obj = xskxceiver__open_and_load();
+	open_opts.prog_ifindex = ifindex;
+
+	ifobject->bpf_obj = xskxceiver__open_opts(&open_opts);
 	if (libbpf_get_error(ifobject->bpf_obj))
 		exit_with_error(libbpf_get_error(ifobject->bpf_obj));
 
+	ret = bpf_program__set_flags(bpf_object__find_program_by_name(ifobject->bpf_obj->obj, "rx"),
+				     BPF_F_XDP_HAS_METADATA);
+	if (ret < 0)
+		exit_with_error(ret);
+
+	ret = xskxceiver__load(ifobject->bpf_obj);
+	if (ret < 0)
+		exit_with_error(ret);
+
 	if (ifobject->umem->unaligned_mode)
 		mmap_flags |= MAP_HUGETLB;
 
-- 
2.38.1.273.g43a17bfeac-goog


  parent reply	other threads:[~2022-10-27 20:00 UTC|newest]

Thread overview: 50+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-10-27 20:00 [xdp-hints] [RFC bpf-next 0/5] xdp: hints via kfuncs Stanislav Fomichev
2022-10-27 20:00 ` [xdp-hints] [RFC bpf-next 1/5] bpf: Support inlined/unrolled kfuncs for xdp metadata Stanislav Fomichev
2022-10-27 20:00 ` [xdp-hints] [RFC bpf-next 2/5] veth: Support rx timestamp metadata for xdp Stanislav Fomichev
2022-10-28  8:40   ` [xdp-hints] " Jesper Dangaard Brouer
2022-10-28 18:46     ` Stanislav Fomichev
2022-10-27 20:00 ` [xdp-hints] [RFC bpf-next 3/5] libbpf: Pass prog_ifindex via bpf_object_open_opts Stanislav Fomichev
2022-10-27 20:05   ` [xdp-hints] " Andrii Nakryiko
2022-10-27 20:10     ` Stanislav Fomichev
2022-10-27 20:00 ` [xdp-hints] [RFC bpf-next 4/5] selftests/bpf: Convert xskxceiver to use custom program Stanislav Fomichev
2022-10-27 20:00 ` Stanislav Fomichev [this message]
2022-10-28  6:22   ` [xdp-hints] Re: [RFC bpf-next 5/5] selftests/bpf: Test rx_timestamp metadata in xskxceiver Martin KaFai Lau
2022-10-28 10:37     ` Jesper Dangaard Brouer
2022-10-28 18:46       ` Stanislav Fomichev
2022-10-31 14:20         ` Alexander Lobakin
2022-10-31 14:29           ` Alexander Lobakin
2022-10-31 17:00           ` Stanislav Fomichev
2022-11-01 13:18             ` Jesper Dangaard Brouer
2022-11-01 20:12               ` Stanislav Fomichev
2022-11-01 22:23               ` Toke Høiland-Jørgensen
2022-10-28 15:58 ` [xdp-hints] Re: [RFC bpf-next 0/5] xdp: hints via kfuncs John Fastabend
2022-10-28 18:04   ` Jakub Kicinski
2022-10-28 18:46     ` Stanislav Fomichev
2022-10-28 23:16       ` John Fastabend
2022-10-29  1:14         ` Jakub Kicinski
2022-10-31 14:10           ` Bezdeka, Florian
2022-10-31 15:28             ` Toke Høiland-Jørgensen
2022-10-31 17:00               ` Stanislav Fomichev
2022-10-31 22:57                 ` Martin KaFai Lau
2022-11-01  1:59                   ` Stanislav Fomichev
2022-11-01 12:52                     ` Toke Høiland-Jørgensen
2022-11-01 13:43                       ` David Ahern
2022-11-01 14:20                         ` Toke Høiland-Jørgensen
2022-11-01 17:05                     ` Martin KaFai Lau
2022-11-01 20:12                       ` Stanislav Fomichev
2022-11-02 14:06                       ` Jesper Dangaard Brouer
2022-11-02 22:01                         ` Toke Høiland-Jørgensen
2022-11-02 23:10                           ` Stanislav Fomichev
2022-11-03  0:09                             ` Toke Høiland-Jørgensen
2022-11-03 12:01                               ` Jesper Dangaard Brouer
2022-11-03 12:48                                 ` Toke Høiland-Jørgensen
2022-11-03 15:25                                   ` Jesper Dangaard Brouer
2022-10-31 19:36               ` Yonghong Song
2022-10-31 22:09                 ` Stanislav Fomichev
2022-10-31 22:38                   ` Yonghong Song
2022-10-31 22:55                     ` Stanislav Fomichev
2022-11-01 14:23                       ` Jesper Dangaard Brouer
2022-11-01 17:31                   ` Martin KaFai Lau
2022-11-01 20:12                     ` Stanislav Fomichev
2022-11-01 21:17                       ` Martin KaFai Lau
2022-10-31 17:01           ` John Fastabend

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

  List information: https://lists.xdp-project.net/postorius/lists/xdp-hints.xdp-project.net/

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20221027200019.4106375-6-sdf@google.com \
    --to=sdf@google.com \
    --cc=alexandr.lobakin@intel.com \
    --cc=anatoly.burakov@intel.com \
    --cc=andrii@kernel.org \
    --cc=ast@kernel.org \
    --cc=bpf@vger.kernel.org \
    --cc=brouer@redhat.com \
    --cc=daniel@iogearbox.net \
    --cc=haoluo@google.com \
    --cc=john.fastabend@gmail.com \
    --cc=jolsa@kernel.org \
    --cc=kpsingh@kernel.org \
    --cc=kuba@kernel.org \
    --cc=magnus.karlsson@gmail.com \
    --cc=martin.lau@linux.dev \
    --cc=mtahhan@redhat.com \
    --cc=netdev@vger.kernel.org \
    --cc=song@kernel.org \
    --cc=willemb@google.com \
    --cc=xdp-hints@xdp-project.net \
    --cc=yhs@fb.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox