2023-04-12 12:48:37

by Jesper Dangaard Brouer

[permalink] [raw]
Subject: [PATCH bpf V8 0/7] XDP-hints: API change for RX-hash kfunc bpf_xdp_metadata_rx_hash

Current API for bpf_xdp_metadata_rx_hash() returns the raw RSS hash value,
but doesn't provide information on the RSS hash type (part of 6.3-rc).

This patchset proposal is to change the function call signature via adding
a pointer value argument for providing the RSS hash type.

Patchset also disables all bpf_printk's from xdp_hw_metadata program
that we expect driver developers to use. Instead counters are introduced
for relaying e.g. skip and fail info to end-user, this can be further
debugged by re-enabling bpf_printk (when driver devel troubleshoot).

---

Jesper Dangaard Brouer (7):
selftests/bpf: xdp_hw_metadata default disable bpf_printk
selftests/bpf: Add counters to xdp_hw_metadata
xdp: rss hash types representation
mlx5: bpf_xdp_metadata_rx_hash add xdp rss hash type
veth: bpf_xdp_metadata_rx_hash add xdp rss hash type
mlx4: bpf_xdp_metadata_rx_hash add xdp rss hash type
selftests/bpf: Adjust bpf_xdp_metadata_rx_hash for new arg


drivers/net/ethernet/mellanox/mlx4/en_rx.c | 22 ++++++-
drivers/net/ethernet/mellanox/mlx4/mlx4_en.h | 3 +-
.../net/ethernet/mellanox/mlx5/core/en/xdp.c | 63 ++++++++++++++++++-
drivers/net/veth.c | 10 ++-
include/linux/mlx5/device.h | 14 ++++-
include/linux/netdevice.h | 3 +-
include/net/xdp.h | 47 ++++++++++++++
net/core/xdp.c | 10 ++-
.../selftests/bpf/prog_tests/xdp_metadata.c | 2 +
.../selftests/bpf/progs/xdp_hw_metadata.c | 42 ++++++++++---
.../selftests/bpf/progs/xdp_metadata.c | 6 +-
.../selftests/bpf/progs/xdp_metadata2.c | 7 ++-
tools/testing/selftests/bpf/xdp_hw_metadata.c | 10 ++-
tools/testing/selftests/bpf/xdp_metadata.h | 4 ++
14 files changed, 213 insertions(+), 30 deletions(-)

--


2023-04-12 12:49:22

by Jesper Dangaard Brouer

[permalink] [raw]
Subject: [PATCH bpf V8 6/7] mlx4: bpf_xdp_metadata_rx_hash add xdp rss hash type

Update API for bpf_xdp_metadata_rx_hash() with arg for xdp rss hash type
via matching individual Completion Queue Entry (CQE) status bits.

Fixes: ab46182d0dcb ("net/mlx4_en: Support RX XDP metadata")
Signed-off-by: Jesper Dangaard Brouer <[email protected]>
Acked-by: Toke Høiland-Jørgensen <[email protected]>
Acked-by: Stanislav Fomichev <[email protected]>
---
drivers/net/ethernet/mellanox/mlx4/en_rx.c | 19 ++++++++++++++++++-
1 file changed, 18 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/mellanox/mlx4/en_rx.c b/drivers/net/ethernet/mellanox/mlx4/en_rx.c
index 73d10aa4c503..332472fe4990 100644
--- a/drivers/net/ethernet/mellanox/mlx4/en_rx.c
+++ b/drivers/net/ethernet/mellanox/mlx4/en_rx.c
@@ -685,11 +685,28 @@ int mlx4_en_xdp_rx_hash(const struct xdp_md *ctx, u32 *hash,
enum xdp_rss_hash_type *rss_type)
{
struct mlx4_en_xdp_buff *_ctx = (void *)ctx;
+ struct mlx4_cqe *cqe = _ctx->cqe;
+ enum xdp_rss_hash_type xht = 0;
+ __be16 status;

if (unlikely(!(_ctx->dev->features & NETIF_F_RXHASH)))
return -ENODATA;

- *hash = be32_to_cpu(_ctx->cqe->immed_rss_invalid);
+ *hash = be32_to_cpu(cqe->immed_rss_invalid);
+ status = cqe->status;
+ if (status & cpu_to_be16(MLX4_CQE_STATUS_TCP))
+ xht = XDP_RSS_L4_TCP;
+ if (status & cpu_to_be16(MLX4_CQE_STATUS_UDP))
+ xht = XDP_RSS_L4_UDP;
+ if (status & cpu_to_be16(MLX4_CQE_STATUS_IPV4 | MLX4_CQE_STATUS_IPV4F))
+ xht |= XDP_RSS_L3_IPV4;
+ if (status & cpu_to_be16(MLX4_CQE_STATUS_IPV6)) {
+ xht |= XDP_RSS_L3_IPV6;
+ if (cqe->ipv6_ext_mask)
+ xht |= XDP_RSS_L3_DYNHDR;
+ }
+ *rss_type = xht;
+
return 0;
}



2023-04-12 12:49:53

by Jesper Dangaard Brouer

[permalink] [raw]
Subject: [PATCH bpf V8 4/7] mlx5: bpf_xdp_metadata_rx_hash add xdp rss hash type

Update API for bpf_xdp_metadata_rx_hash() with arg for xdp rss hash type
via mapping table.

The mlx5 hardware can also identify and RSS hash IPSEC. This indicate
hash includes SPI (Security Parameters Index) as part of IPSEC hash.

Extend xdp core enum xdp_rss_hash_type with IPSEC hash type.

Fixes: bc8d405b1ba9 ("net/mlx5e: Support RX XDP metadata")
Signed-off-by: Jesper Dangaard Brouer <[email protected]>
Acked-by: Toke Høiland-Jørgensen <[email protected]>
Acked-by: Stanislav Fomichev <[email protected]>
---
drivers/net/ethernet/mellanox/mlx5/core/en/xdp.c | 60 ++++++++++++++++++++++
include/linux/mlx5/device.h | 14 ++++-
include/net/xdp.h | 2 +
3 files changed, 73 insertions(+), 3 deletions(-)

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en/xdp.c b/drivers/net/ethernet/mellanox/mlx5/core/en/xdp.c
index efe609f8e3aa..d9d3b9e1f15a 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en/xdp.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en/xdp.c
@@ -34,6 +34,7 @@
#include <net/xdp_sock_drv.h>
#include "en/xdp.h"
#include "en/params.h"
+#include <linux/bitfield.h>

int mlx5e_xdp_max_mtu(struct mlx5e_params *params, struct mlx5e_xsk_param *xsk)
{
@@ -169,15 +170,72 @@ static int mlx5e_xdp_rx_timestamp(const struct xdp_md *ctx, u64 *timestamp)
return 0;
}

+/* Mapping HW RSS Type bits CQE_RSS_HTYPE_IP + CQE_RSS_HTYPE_L4 into 4-bits*/
+#define RSS_TYPE_MAX_TABLE 16 /* 4-bits max 16 entries */
+#define RSS_L4 GENMASK(1, 0)
+#define RSS_L3 GENMASK(3, 2) /* Same as CQE_RSS_HTYPE_IP */
+
+/* Valid combinations of CQE_RSS_HTYPE_IP + CQE_RSS_HTYPE_L4 sorted numerical */
+enum mlx5_rss_hash_type {
+ RSS_TYPE_NO_HASH = (FIELD_PREP_CONST(RSS_L3, CQE_RSS_IP_NONE) |
+ FIELD_PREP_CONST(RSS_L4, CQE_RSS_L4_NONE)),
+ RSS_TYPE_L3_IPV4 = (FIELD_PREP_CONST(RSS_L3, CQE_RSS_IPV4) |
+ FIELD_PREP_CONST(RSS_L4, CQE_RSS_L4_NONE)),
+ RSS_TYPE_L4_IPV4_TCP = (FIELD_PREP_CONST(RSS_L3, CQE_RSS_IPV4) |
+ FIELD_PREP_CONST(RSS_L4, CQE_RSS_L4_TCP)),
+ RSS_TYPE_L4_IPV4_UDP = (FIELD_PREP_CONST(RSS_L3, CQE_RSS_IPV4) |
+ FIELD_PREP_CONST(RSS_L4, CQE_RSS_L4_UDP)),
+ RSS_TYPE_L4_IPV4_IPSEC = (FIELD_PREP_CONST(RSS_L3, CQE_RSS_IPV4) |
+ FIELD_PREP_CONST(RSS_L4, CQE_RSS_L4_IPSEC)),
+ RSS_TYPE_L3_IPV6 = (FIELD_PREP_CONST(RSS_L3, CQE_RSS_IPV6) |
+ FIELD_PREP_CONST(RSS_L4, CQE_RSS_L4_NONE)),
+ RSS_TYPE_L4_IPV6_TCP = (FIELD_PREP_CONST(RSS_L3, CQE_RSS_IPV6) |
+ FIELD_PREP_CONST(RSS_L4, CQE_RSS_L4_TCP)),
+ RSS_TYPE_L4_IPV6_UDP = (FIELD_PREP_CONST(RSS_L3, CQE_RSS_IPV6) |
+ FIELD_PREP_CONST(RSS_L4, CQE_RSS_L4_UDP)),
+ RSS_TYPE_L4_IPV6_IPSEC = (FIELD_PREP_CONST(RSS_L3, CQE_RSS_IPV6) |
+ FIELD_PREP_CONST(RSS_L4, CQE_RSS_L4_IPSEC)),
+};
+
+/* Invalid combinations will simply return zero, allows no boundary checks */
+static const enum xdp_rss_hash_type mlx5_xdp_rss_type[RSS_TYPE_MAX_TABLE] = {
+ [RSS_TYPE_NO_HASH] = XDP_RSS_TYPE_NONE,
+ [1] = XDP_RSS_TYPE_NONE, /* Implicit zero */
+ [2] = XDP_RSS_TYPE_NONE, /* Implicit zero */
+ [3] = XDP_RSS_TYPE_NONE, /* Implicit zero */
+ [RSS_TYPE_L3_IPV4] = XDP_RSS_TYPE_L3_IPV4,
+ [RSS_TYPE_L4_IPV4_TCP] = XDP_RSS_TYPE_L4_IPV4_TCP,
+ [RSS_TYPE_L4_IPV4_UDP] = XDP_RSS_TYPE_L4_IPV4_UDP,
+ [RSS_TYPE_L4_IPV4_IPSEC] = XDP_RSS_TYPE_L4_IPV4_IPSEC,
+ [RSS_TYPE_L3_IPV6] = XDP_RSS_TYPE_L3_IPV6,
+ [RSS_TYPE_L4_IPV6_TCP] = XDP_RSS_TYPE_L4_IPV6_TCP,
+ [RSS_TYPE_L4_IPV6_UDP] = XDP_RSS_TYPE_L4_IPV6_UDP,
+ [RSS_TYPE_L4_IPV6_IPSEC] = XDP_RSS_TYPE_L4_IPV6_IPSEC,
+ [12] = XDP_RSS_TYPE_NONE, /* Implicit zero */
+ [13] = XDP_RSS_TYPE_NONE, /* Implicit zero */
+ [14] = XDP_RSS_TYPE_NONE, /* Implicit zero */
+ [15] = XDP_RSS_TYPE_NONE, /* Implicit zero */
+};
+
static int mlx5e_xdp_rx_hash(const struct xdp_md *ctx, u32 *hash,
enum xdp_rss_hash_type *rss_type)
{
const struct mlx5e_xdp_buff *_ctx = (void *)ctx;
+ const struct mlx5_cqe64 *cqe = _ctx->cqe;
+ u32 hash_type, l4_type, ip_type, lookup;

if (unlikely(!(_ctx->xdp.rxq->dev->features & NETIF_F_RXHASH)))
return -ENODATA;

- *hash = be32_to_cpu(_ctx->cqe->rss_hash_result);
+ *hash = be32_to_cpu(cqe->rss_hash_result);
+
+ hash_type = cqe->rss_hash_type;
+ BUILD_BUG_ON(CQE_RSS_HTYPE_IP != RSS_L3); /* same mask */
+ ip_type = hash_type & CQE_RSS_HTYPE_IP;
+ l4_type = FIELD_GET(CQE_RSS_HTYPE_L4, hash_type);
+ lookup = ip_type | l4_type;
+ *rss_type = mlx5_xdp_rss_type[lookup];
+
return 0;
}

diff --git a/include/linux/mlx5/device.h b/include/linux/mlx5/device.h
index 71b06ebad402..1db19a9d26e3 100644
--- a/include/linux/mlx5/device.h
+++ b/include/linux/mlx5/device.h
@@ -36,6 +36,7 @@
#include <linux/types.h>
#include <rdma/ib_verbs.h>
#include <linux/mlx5/mlx5_ifc.h>
+#include <linux/bitfield.h>

#if defined(__LITTLE_ENDIAN)
#define MLX5_SET_HOST_ENDIANNESS 0
@@ -980,14 +981,23 @@ enum {
};

enum {
- CQE_RSS_HTYPE_IP = 0x3 << 2,
+ CQE_RSS_HTYPE_IP = GENMASK(3, 2),
/* cqe->rss_hash_type[3:2] - IP destination selected for hash
* (00 = none, 01 = IPv4, 10 = IPv6, 11 = Reserved)
*/
- CQE_RSS_HTYPE_L4 = 0x3 << 6,
+ CQE_RSS_IP_NONE = 0x0,
+ CQE_RSS_IPV4 = 0x1,
+ CQE_RSS_IPV6 = 0x2,
+ CQE_RSS_RESERVED = 0x3,
+
+ CQE_RSS_HTYPE_L4 = GENMASK(7, 6),
/* cqe->rss_hash_type[7:6] - L4 destination selected for hash
* (00 = none, 01 = TCP. 10 = UDP, 11 = IPSEC.SPI
*/
+ CQE_RSS_L4_NONE = 0x0,
+ CQE_RSS_L4_TCP = 0x1,
+ CQE_RSS_L4_UDP = 0x2,
+ CQE_RSS_L4_IPSEC = 0x3,
};

enum {
diff --git a/include/net/xdp.h b/include/net/xdp.h
index a76c4ea203ea..76aa748e7923 100644
--- a/include/net/xdp.h
+++ b/include/net/xdp.h
@@ -460,10 +460,12 @@ enum xdp_rss_hash_type {
XDP_RSS_TYPE_L4_IPV4_TCP = XDP_RSS_L3_IPV4 | XDP_RSS_L4 | XDP_RSS_L4_TCP,
XDP_RSS_TYPE_L4_IPV4_UDP = XDP_RSS_L3_IPV4 | XDP_RSS_L4 | XDP_RSS_L4_UDP,
XDP_RSS_TYPE_L4_IPV4_SCTP = XDP_RSS_L3_IPV4 | XDP_RSS_L4 | XDP_RSS_L4_SCTP,
+ XDP_RSS_TYPE_L4_IPV4_IPSEC = XDP_RSS_L3_IPV4 | XDP_RSS_L4 | XDP_RSS_L4_IPSEC,

XDP_RSS_TYPE_L4_IPV6_TCP = XDP_RSS_L3_IPV6 | XDP_RSS_L4 | XDP_RSS_L4_TCP,
XDP_RSS_TYPE_L4_IPV6_UDP = XDP_RSS_L3_IPV6 | XDP_RSS_L4 | XDP_RSS_L4_UDP,
XDP_RSS_TYPE_L4_IPV6_SCTP = XDP_RSS_L3_IPV6 | XDP_RSS_L4 | XDP_RSS_L4_SCTP,
+ XDP_RSS_TYPE_L4_IPV6_IPSEC = XDP_RSS_L3_IPV6 | XDP_RSS_L4 | XDP_RSS_L4_IPSEC,

XDP_RSS_TYPE_L4_IPV6_TCP_EX = XDP_RSS_TYPE_L4_IPV6_TCP | XDP_RSS_L3_DYNHDR,
XDP_RSS_TYPE_L4_IPV6_UDP_EX = XDP_RSS_TYPE_L4_IPV6_UDP | XDP_RSS_L3_DYNHDR,


2023-04-12 12:50:00

by Jesper Dangaard Brouer

[permalink] [raw]
Subject: [PATCH bpf V8 7/7] selftests/bpf: Adjust bpf_xdp_metadata_rx_hash for new arg

Update BPF selftests to use the new RSS type argument for kfunc
bpf_xdp_metadata_rx_hash.

Signed-off-by: Jesper Dangaard Brouer <[email protected]>
Acked-by: Toke Høiland-Jørgensen <[email protected]>
Acked-by: Stanislav Fomichev <[email protected]>
---
.../selftests/bpf/prog_tests/xdp_metadata.c | 2 ++
.../testing/selftests/bpf/progs/xdp_hw_metadata.c | 11 +++++------
tools/testing/selftests/bpf/progs/xdp_metadata.c | 6 +++---
tools/testing/selftests/bpf/progs/xdp_metadata2.c | 7 ++++---
tools/testing/selftests/bpf/xdp_hw_metadata.c | 6 +++++-
tools/testing/selftests/bpf/xdp_metadata.h | 4 ++++
6 files changed, 23 insertions(+), 13 deletions(-)

diff --git a/tools/testing/selftests/bpf/prog_tests/xdp_metadata.c b/tools/testing/selftests/bpf/prog_tests/xdp_metadata.c
index aa4beae99f4f..8c5e98da9ae9 100644
--- a/tools/testing/selftests/bpf/prog_tests/xdp_metadata.c
+++ b/tools/testing/selftests/bpf/prog_tests/xdp_metadata.c
@@ -273,6 +273,8 @@ static int verify_xsk_metadata(struct xsk *xsk)
if (!ASSERT_NEQ(meta->rx_hash, 0, "rx_hash"))
return -1;

+ ASSERT_EQ(meta->rx_hash_type, 0, "rx_hash_type");
+
xsk_ring_cons__release(&xsk->rx, 1);
refill_rx(xsk, comp_addr);

diff --git a/tools/testing/selftests/bpf/progs/xdp_hw_metadata.c b/tools/testing/selftests/bpf/progs/xdp_hw_metadata.c
index a07ef7534013..829b7c3354ba 100644
--- a/tools/testing/selftests/bpf/progs/xdp_hw_metadata.c
+++ b/tools/testing/selftests/bpf/progs/xdp_hw_metadata.c
@@ -31,8 +31,8 @@ volatile __u64 pkts_redir = 0;

extern int bpf_xdp_metadata_rx_timestamp(const struct xdp_md *ctx,
__u64 *timestamp) __ksym;
-extern int bpf_xdp_metadata_rx_hash(const struct xdp_md *ctx,
- __u32 *hash) __ksym;
+extern int bpf_xdp_metadata_rx_hash(const struct xdp_md *ctx, __u32 *hash,
+ enum xdp_rss_hash_type *rss_type) __ksym;

SEC("xdp")
int rx(struct xdp_md *ctx)
@@ -96,10 +96,9 @@ int rx(struct xdp_md *ctx)
else
meta->rx_timestamp = 0; /* Used by AF_XDP as not avail signal */

- if (!bpf_xdp_metadata_rx_hash(ctx, &meta->rx_hash))
- bpf_printk("populated rx_hash with %u", meta->rx_hash);
- else
- meta->rx_hash = 0; /* Used by AF_XDP as not avail signal */
+ ret = bpf_xdp_metadata_rx_hash(ctx, &meta->rx_hash, &meta->rx_hash_type);
+ if (ret < 0)
+ meta->rx_hash_err = ret; /* Used by AF_XDP as no hash signal */

pkts_redir++;
return bpf_redirect_map(&xsk, ctx->rx_queue_index, XDP_PASS);
diff --git a/tools/testing/selftests/bpf/progs/xdp_metadata.c b/tools/testing/selftests/bpf/progs/xdp_metadata.c
index 77678b034389..d151d406a123 100644
--- a/tools/testing/selftests/bpf/progs/xdp_metadata.c
+++ b/tools/testing/selftests/bpf/progs/xdp_metadata.c
@@ -21,8 +21,8 @@ struct {

extern int bpf_xdp_metadata_rx_timestamp(const struct xdp_md *ctx,
__u64 *timestamp) __ksym;
-extern int bpf_xdp_metadata_rx_hash(const struct xdp_md *ctx,
- __u32 *hash) __ksym;
+extern int bpf_xdp_metadata_rx_hash(const struct xdp_md *ctx, __u32 *hash,
+ enum xdp_rss_hash_type *rss_type) __ksym;

SEC("xdp")
int rx(struct xdp_md *ctx)
@@ -56,7 +56,7 @@ int rx(struct xdp_md *ctx)
if (timestamp == 0)
meta->rx_timestamp = 1;

- bpf_xdp_metadata_rx_hash(ctx, &meta->rx_hash);
+ bpf_xdp_metadata_rx_hash(ctx, &meta->rx_hash, &meta->rx_hash_type);

return bpf_redirect_map(&xsk, ctx->rx_queue_index, XDP_PASS);
}
diff --git a/tools/testing/selftests/bpf/progs/xdp_metadata2.c b/tools/testing/selftests/bpf/progs/xdp_metadata2.c
index cf69d05451c3..85f88d9d7a78 100644
--- a/tools/testing/selftests/bpf/progs/xdp_metadata2.c
+++ b/tools/testing/selftests/bpf/progs/xdp_metadata2.c
@@ -5,17 +5,18 @@
#include <bpf/bpf_helpers.h>
#include <bpf/bpf_endian.h>

-extern int bpf_xdp_metadata_rx_hash(const struct xdp_md *ctx,
- __u32 *hash) __ksym;
+extern int bpf_xdp_metadata_rx_hash(const struct xdp_md *ctx, __u32 *hash,
+ enum xdp_rss_hash_type *rss_type) __ksym;

int called;

SEC("freplace/rx")
int freplace_rx(struct xdp_md *ctx)
{
+ enum xdp_rss_hash_type type = 0;
u32 hash = 0;
/* Call _any_ metadata function to make sure we don't crash. */
- bpf_xdp_metadata_rx_hash(ctx, &hash);
+ bpf_xdp_metadata_rx_hash(ctx, &hash, &type);
called++;
return XDP_PASS;
}
diff --git a/tools/testing/selftests/bpf/xdp_hw_metadata.c b/tools/testing/selftests/bpf/xdp_hw_metadata.c
index 3b942ef7297b..987cf0db5ebc 100644
--- a/tools/testing/selftests/bpf/xdp_hw_metadata.c
+++ b/tools/testing/selftests/bpf/xdp_hw_metadata.c
@@ -141,7 +141,11 @@ static void verify_xdp_metadata(void *data)
meta = data - sizeof(*meta);

printf("rx_timestamp: %llu\n", meta->rx_timestamp);
- printf("rx_hash: %u\n", meta->rx_hash);
+ if (meta->rx_hash_err < 0)
+ printf("No rx_hash err=%d\n", meta->rx_hash_err);
+ else
+ printf("rx_hash: 0x%X with RSS type:0x%X\n",
+ meta->rx_hash, meta->rx_hash_type);
}

static void verify_skb_metadata(int fd)
diff --git a/tools/testing/selftests/bpf/xdp_metadata.h b/tools/testing/selftests/bpf/xdp_metadata.h
index f6780fbb0a21..0c4624dc6f2f 100644
--- a/tools/testing/selftests/bpf/xdp_metadata.h
+++ b/tools/testing/selftests/bpf/xdp_metadata.h
@@ -12,4 +12,8 @@
struct xdp_meta {
__u64 rx_timestamp;
__u32 rx_hash;
+ union {
+ __u32 rx_hash_type;
+ __s32 rx_hash_err;
+ };
};


2023-04-12 12:50:27

by Jesper Dangaard Brouer

[permalink] [raw]
Subject: [PATCH bpf V8 2/7] selftests/bpf: Add counters to xdp_hw_metadata

Add counters for skipped, failed and redirected packets.
The xdp_hw_metadata program only redirects UDP port 9091.
This helps users to quickly identify then packets are
skipped and identify failures of bpf_xdp_adjust_meta.

Signed-off-by: Jesper Dangaard Brouer <[email protected]>
---
.../testing/selftests/bpf/progs/xdp_hw_metadata.c | 15 +++++++++++++--
tools/testing/selftests/bpf/xdp_hw_metadata.c | 4 +++-
2 files changed, 16 insertions(+), 3 deletions(-)

diff --git a/tools/testing/selftests/bpf/progs/xdp_hw_metadata.c b/tools/testing/selftests/bpf/progs/xdp_hw_metadata.c
index b0104763405a..a07ef7534013 100644
--- a/tools/testing/selftests/bpf/progs/xdp_hw_metadata.c
+++ b/tools/testing/selftests/bpf/progs/xdp_hw_metadata.c
@@ -25,6 +25,10 @@ struct {
__type(value, __u32);
} xsk SEC(".maps");

+volatile __u64 pkts_skip = 0;
+volatile __u64 pkts_fail = 0;
+volatile __u64 pkts_redir = 0;
+
extern int bpf_xdp_metadata_rx_timestamp(const struct xdp_md *ctx,
__u64 *timestamp) __ksym;
extern int bpf_xdp_metadata_rx_hash(const struct xdp_md *ctx,
@@ -59,16 +63,21 @@ int rx(struct xdp_md *ctx)
udp = NULL;
}

- if (!udp)
+ if (!udp) {
+ pkts_skip++;
return XDP_PASS;
+ }

/* Forwarding UDP:9091 to AF_XDP */
- if (udp->dest != bpf_htons(9091))
+ if (udp->dest != bpf_htons(9091)) {
+ pkts_skip++;
return XDP_PASS;
+ }

ret = bpf_xdp_adjust_meta(ctx, -(int)sizeof(struct xdp_meta));
if (ret != 0) {
bpf_printk("bpf_xdp_adjust_meta returned %d", ret);
+ pkts_fail++;
return XDP_PASS;
}

@@ -78,6 +87,7 @@ int rx(struct xdp_md *ctx)

if (meta + 1 > data) {
bpf_printk("bpf_xdp_adjust_meta doesn't appear to work");
+ pkts_fail++;
return XDP_PASS;
}

@@ -91,6 +101,7 @@ int rx(struct xdp_md *ctx)
else
meta->rx_hash = 0; /* Used by AF_XDP as not avail signal */

+ pkts_redir++;
return bpf_redirect_map(&xsk, ctx->rx_queue_index, XDP_PASS);
}

diff --git a/tools/testing/selftests/bpf/xdp_hw_metadata.c b/tools/testing/selftests/bpf/xdp_hw_metadata.c
index 1c8acb68b977..3b942ef7297b 100644
--- a/tools/testing/selftests/bpf/xdp_hw_metadata.c
+++ b/tools/testing/selftests/bpf/xdp_hw_metadata.c
@@ -212,7 +212,9 @@ static int verify_metadata(struct xsk *rx_xsk, int rxq, int server_fd)
while (true) {
errno = 0;
ret = poll(fds, rxq + 1, 1000);
- printf("poll: %d (%d)\n", ret, errno);
+ printf("poll: %d (%d) skip=%llu fail=%llu redir=%llu\n",
+ ret, errno, bpf_obj->bss->pkts_skip,
+ bpf_obj->bss->pkts_fail, bpf_obj->bss->pkts_redir);
if (ret < 0)
break;
if (ret == 0)


2023-04-12 12:50:27

by Jesper Dangaard Brouer

[permalink] [raw]
Subject: [PATCH bpf V8 1/7] selftests/bpf: xdp_hw_metadata default disable bpf_printk

The tool xdp_hw_metadata can be used by driver developers
implementing XDP-hints kfuncs. The tool transfers the
XDP-hints via metadata information to an AF_XDP userspace
process. When everything works the bpf_printk calls are
unncesssary. Thus, disable bpf_printk by default, but
make it easy to reenable for driver developers to use
when debugging their driver implementation.

Next patch will add counters to track some of these cases.
That will provide a hint to re-enable bpf_printk.

This also converts bpf_printk "forwarding UDP:9091 to AF_XDP"
into a code comment. The bpf_printk's that are important
to the driver developers is when bpf_xdp_adjust_meta fails.
The likely mistake from driver developers is expected to
be that they didn't implement XDP metadata adjust support.

Signed-off-by: Jesper Dangaard Brouer <[email protected]>
---
.../testing/selftests/bpf/progs/xdp_hw_metadata.c | 16 ++++++++++++++--
1 file changed, 14 insertions(+), 2 deletions(-)

diff --git a/tools/testing/selftests/bpf/progs/xdp_hw_metadata.c b/tools/testing/selftests/bpf/progs/xdp_hw_metadata.c
index 4c55b4d79d3d..b0104763405a 100644
--- a/tools/testing/selftests/bpf/progs/xdp_hw_metadata.c
+++ b/tools/testing/selftests/bpf/progs/xdp_hw_metadata.c
@@ -5,6 +5,19 @@
#include <bpf/bpf_helpers.h>
#include <bpf/bpf_endian.h>

+/* Per default below bpf_printk() calls are disabled. Can be
+ * reenabled manually for convenience by XDP-hints driver developer,
+ * when troubleshooting the drivers kfuncs implementation details.
+ *
+ * Remember BPF-prog bpf_printk info output can be access via:
+ * /sys/kernel/debug/tracing/trace_pipe
+ */
+//#define DEBUG 1
+#ifndef DEBUG
+#undef bpf_printk
+#define bpf_printk(fmt, ...) ({})
+#endif
+
struct {
__uint(type, BPF_MAP_TYPE_XSKMAP);
__uint(max_entries, 256);
@@ -49,11 +62,10 @@ int rx(struct xdp_md *ctx)
if (!udp)
return XDP_PASS;

+ /* Forwarding UDP:9091 to AF_XDP */
if (udp->dest != bpf_htons(9091))
return XDP_PASS;

- bpf_printk("forwarding UDP:9091 to AF_XDP");
-
ret = bpf_xdp_adjust_meta(ctx, -(int)sizeof(struct xdp_meta));
if (ret != 0) {
bpf_printk("bpf_xdp_adjust_meta returned %d", ret);


2023-04-12 12:50:42

by Jesper Dangaard Brouer

[permalink] [raw]
Subject: [PATCH bpf V8 3/7] xdp: rss hash types representation

The RSS hash type specifies what portion of packet data NIC hardware used
when calculating RSS hash value. The RSS types are focused on Internet
traffic protocols at OSI layers L3 and L4. L2 (e.g. ARP) often get hash
value zero and no RSS type. For L3 focused on IPv4 vs. IPv6, and L4
primarily TCP vs UDP, but some hardware supports SCTP.

Hardware RSS types are differently encoded for each hardware NIC. Most
hardware represent RSS hash type as a number. Determining L3 vs L4 often
requires a mapping table as there often isn't a pattern or sorting
according to ISO layer.

The patch introduce a XDP RSS hash type (enum xdp_rss_hash_type) that
contains both BITs for the L3/L4 types, and combinations to be used by
drivers for their mapping tables. The enum xdp_rss_type_bits get exposed
to BPF via BTF, and it is up to the BPF-programmer to match using these
defines.

This proposal change the kfunc API bpf_xdp_metadata_rx_hash() adding
a pointer value argument for provide the RSS hash type.
Change signature for all xmo_rx_hash calls in drivers to make it compile.

The RSS type implementations for each driver comes as separate patches.

Fixes: 3d76a4d3d4e5 ("bpf: XDP metadata RX kfuncs")
Signed-off-by: Jesper Dangaard Brouer <[email protected]>
Acked-by: Toke Høiland-Jørgensen <[email protected]>
Acked-by: Stanislav Fomichev <[email protected]>
---
drivers/net/ethernet/mellanox/mlx4/en_rx.c | 3 +
drivers/net/ethernet/mellanox/mlx4/mlx4_en.h | 3 +
drivers/net/ethernet/mellanox/mlx5/core/en/xdp.c | 3 +
drivers/net/veth.c | 3 +
include/linux/netdevice.h | 3 +
include/net/xdp.h | 45 ++++++++++++++++++++++
net/core/xdp.c | 10 ++++-
7 files changed, 64 insertions(+), 6 deletions(-)

diff --git a/drivers/net/ethernet/mellanox/mlx4/en_rx.c b/drivers/net/ethernet/mellanox/mlx4/en_rx.c
index 4b5e459b6d49..73d10aa4c503 100644
--- a/drivers/net/ethernet/mellanox/mlx4/en_rx.c
+++ b/drivers/net/ethernet/mellanox/mlx4/en_rx.c
@@ -681,7 +681,8 @@ int mlx4_en_xdp_rx_timestamp(const struct xdp_md *ctx, u64 *timestamp)
return 0;
}

-int mlx4_en_xdp_rx_hash(const struct xdp_md *ctx, u32 *hash)
+int mlx4_en_xdp_rx_hash(const struct xdp_md *ctx, u32 *hash,
+ enum xdp_rss_hash_type *rss_type)
{
struct mlx4_en_xdp_buff *_ctx = (void *)ctx;

diff --git a/drivers/net/ethernet/mellanox/mlx4/mlx4_en.h b/drivers/net/ethernet/mellanox/mlx4/mlx4_en.h
index 544e09b97483..4ac4d883047b 100644
--- a/drivers/net/ethernet/mellanox/mlx4/mlx4_en.h
+++ b/drivers/net/ethernet/mellanox/mlx4/mlx4_en.h
@@ -798,7 +798,8 @@ int mlx4_en_netdev_event(struct notifier_block *this,

struct xdp_md;
int mlx4_en_xdp_rx_timestamp(const struct xdp_md *ctx, u64 *timestamp);
-int mlx4_en_xdp_rx_hash(const struct xdp_md *ctx, u32 *hash);
+int mlx4_en_xdp_rx_hash(const struct xdp_md *ctx, u32 *hash,
+ enum xdp_rss_hash_type *rss_type);

/*
* Functions for time stamping
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en/xdp.c b/drivers/net/ethernet/mellanox/mlx5/core/en/xdp.c
index c5dae48b7932..efe609f8e3aa 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en/xdp.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en/xdp.c
@@ -169,7 +169,8 @@ static int mlx5e_xdp_rx_timestamp(const struct xdp_md *ctx, u64 *timestamp)
return 0;
}

-static int mlx5e_xdp_rx_hash(const struct xdp_md *ctx, u32 *hash)
+static int mlx5e_xdp_rx_hash(const struct xdp_md *ctx, u32 *hash,
+ enum xdp_rss_hash_type *rss_type)
{
const struct mlx5e_xdp_buff *_ctx = (void *)ctx;

diff --git a/drivers/net/veth.c b/drivers/net/veth.c
index c1178915496d..424e8876a16b 100644
--- a/drivers/net/veth.c
+++ b/drivers/net/veth.c
@@ -1648,7 +1648,8 @@ static int veth_xdp_rx_timestamp(const struct xdp_md *ctx, u64 *timestamp)
return 0;
}

-static int veth_xdp_rx_hash(const struct xdp_md *ctx, u32 *hash)
+static int veth_xdp_rx_hash(const struct xdp_md *ctx, u32 *hash,
+ enum xdp_rss_hash_type *rss_type)
{
struct veth_xdp_buff *_ctx = (void *)ctx;

diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index 470085b121d3..c35f04f636f1 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -1624,7 +1624,8 @@ struct net_device_ops {

struct xdp_metadata_ops {
int (*xmo_rx_timestamp)(const struct xdp_md *ctx, u64 *timestamp);
- int (*xmo_rx_hash)(const struct xdp_md *ctx, u32 *hash);
+ int (*xmo_rx_hash)(const struct xdp_md *ctx, u32 *hash,
+ enum xdp_rss_hash_type *rss_type);
};

/**
diff --git a/include/net/xdp.h b/include/net/xdp.h
index 41c57b8b1671..a76c4ea203ea 100644
--- a/include/net/xdp.h
+++ b/include/net/xdp.h
@@ -8,6 +8,7 @@

#include <linux/skbuff.h> /* skb_shared_info */
#include <uapi/linux/netdev.h>
+#include <linux/bitfield.h>

/**
* DOC: XDP RX-queue information
@@ -425,6 +426,50 @@ XDP_METADATA_KFUNC_xxx
MAX_XDP_METADATA_KFUNC,
};

+enum xdp_rss_hash_type {
+ /* First part: Individual bits for L3/L4 types */
+ XDP_RSS_L3_IPV4 = BIT(0),
+ XDP_RSS_L3_IPV6 = BIT(1),
+
+ /* The fixed (L3) IPv4 and IPv6 headers can both be followed by
+ * variable/dynamic headers, IPv4 called Options and IPv6 called
+ * Extension Headers. HW RSS type can contain this info.
+ */
+ XDP_RSS_L3_DYNHDR = BIT(2),
+
+ /* When RSS hash covers L4 then drivers MUST set XDP_RSS_L4 bit in
+ * addition to the protocol specific bit. This ease interaction with
+ * SKBs and avoids reserving a fixed mask for future L4 protocol bits.
+ */
+ XDP_RSS_L4 = BIT(3), /* L4 based hash, proto can be unknown */
+ XDP_RSS_L4_TCP = BIT(4),
+ XDP_RSS_L4_UDP = BIT(5),
+ XDP_RSS_L4_SCTP = BIT(6),
+ XDP_RSS_L4_IPSEC = BIT(7), /* L4 based hash include IPSEC SPI */
+
+ /* Second part: RSS hash type combinations used for driver HW mapping */
+ XDP_RSS_TYPE_NONE = 0,
+ XDP_RSS_TYPE_L2 = XDP_RSS_TYPE_NONE,
+
+ XDP_RSS_TYPE_L3_IPV4 = XDP_RSS_L3_IPV4,
+ XDP_RSS_TYPE_L3_IPV6 = XDP_RSS_L3_IPV6,
+ XDP_RSS_TYPE_L3_IPV4_OPT = XDP_RSS_L3_IPV4 | XDP_RSS_L3_DYNHDR,
+ XDP_RSS_TYPE_L3_IPV6_EX = XDP_RSS_L3_IPV6 | XDP_RSS_L3_DYNHDR,
+
+ XDP_RSS_TYPE_L4_ANY = XDP_RSS_L4,
+ XDP_RSS_TYPE_L4_IPV4_TCP = XDP_RSS_L3_IPV4 | XDP_RSS_L4 | XDP_RSS_L4_TCP,
+ XDP_RSS_TYPE_L4_IPV4_UDP = XDP_RSS_L3_IPV4 | XDP_RSS_L4 | XDP_RSS_L4_UDP,
+ XDP_RSS_TYPE_L4_IPV4_SCTP = XDP_RSS_L3_IPV4 | XDP_RSS_L4 | XDP_RSS_L4_SCTP,
+
+ XDP_RSS_TYPE_L4_IPV6_TCP = XDP_RSS_L3_IPV6 | XDP_RSS_L4 | XDP_RSS_L4_TCP,
+ XDP_RSS_TYPE_L4_IPV6_UDP = XDP_RSS_L3_IPV6 | XDP_RSS_L4 | XDP_RSS_L4_UDP,
+ XDP_RSS_TYPE_L4_IPV6_SCTP = XDP_RSS_L3_IPV6 | XDP_RSS_L4 | XDP_RSS_L4_SCTP,
+
+ XDP_RSS_TYPE_L4_IPV6_TCP_EX = XDP_RSS_TYPE_L4_IPV6_TCP | XDP_RSS_L3_DYNHDR,
+ XDP_RSS_TYPE_L4_IPV6_UDP_EX = XDP_RSS_TYPE_L4_IPV6_UDP | XDP_RSS_L3_DYNHDR,
+ XDP_RSS_TYPE_L4_IPV6_SCTP_EX = XDP_RSS_TYPE_L4_IPV6_SCTP | XDP_RSS_L3_DYNHDR,
+};
+
#ifdef CONFIG_NET
u32 bpf_xdp_metadata_kfunc_id(int id);
bool bpf_dev_bound_kfunc_id(u32 btf_id);
diff --git a/net/core/xdp.c b/net/core/xdp.c
index 528d4b37983d..fb85aca81961 100644
--- a/net/core/xdp.c
+++ b/net/core/xdp.c
@@ -734,13 +734,21 @@ __bpf_kfunc int bpf_xdp_metadata_rx_timestamp(const struct xdp_md *ctx, u64 *tim
* bpf_xdp_metadata_rx_hash - Read XDP frame RX hash.
* @ctx: XDP context pointer.
* @hash: Return value pointer.
+ * @rss_type: Return value pointer for RSS type.
+ *
+ * The RSS hash type (@rss_type) specifies what portion of packet headers NIC
+ * hardware used when calculating RSS hash value. The RSS type can be decoded
+ * via &enum xdp_rss_hash_type either matching on individual L3/L4 bits
+ * ``XDP_RSS_L*`` or by combined traditional *RSS Hashing Types*
+ * ``XDP_RSS_TYPE_L*``.
*
* Return:
* * Returns 0 on success or ``-errno`` on error.
* * ``-EOPNOTSUPP`` : means device driver doesn't implement kfunc
* * ``-ENODATA`` : means no RX-hash available for this frame
*/
-__bpf_kfunc int bpf_xdp_metadata_rx_hash(const struct xdp_md *ctx, u32 *hash)
+__bpf_kfunc int bpf_xdp_metadata_rx_hash(const struct xdp_md *ctx, u32 *hash,
+ enum xdp_rss_hash_type *rss_type)
{
return -EOPNOTSUPP;
}


2023-04-12 12:51:03

by Jesper Dangaard Brouer

[permalink] [raw]
Subject: [PATCH bpf V8 5/7] veth: bpf_xdp_metadata_rx_hash add xdp rss hash type

Update API for bpf_xdp_metadata_rx_hash() with arg for xdp rss hash type.

The veth driver currently only support XDP-hints based on SKB code path.
The SKB have lost information about the RSS hash type, by compressing
the information down to a single bitfield skb->l4_hash, that only knows
if this was a L4 hash value.

In preparation for veth, the xdp_rss_hash_type have an L4 indication
bit that allow us to return a meaningful L4 indication when working
with SKB based packets.

Fixes: 306531f0249f ("veth: Support RX XDP metadata")
Signed-off-by: Jesper Dangaard Brouer <[email protected]>
Acked-by: Toke Høiland-Jørgensen <[email protected]>
Acked-by: Stanislav Fomichev <[email protected]>
---
drivers/net/veth.c | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/drivers/net/veth.c b/drivers/net/veth.c
index 424e8876a16b..e1b38fbf1dd9 100644
--- a/drivers/net/veth.c
+++ b/drivers/net/veth.c
@@ -1652,11 +1652,14 @@ static int veth_xdp_rx_hash(const struct xdp_md *ctx, u32 *hash,
enum xdp_rss_hash_type *rss_type)
{
struct veth_xdp_buff *_ctx = (void *)ctx;
+ struct sk_buff *skb = _ctx->skb;

- if (!_ctx->skb)
+ if (!skb)
return -ENODATA;

- *hash = skb_get_hash(_ctx->skb);
+ *hash = skb_get_hash(skb);
+ *rss_type = skb->l4_hash ? XDP_RSS_TYPE_L4_ANY : XDP_RSS_TYPE_NONE;
+
return 0;
}



2023-04-12 17:09:30

by Stanislav Fomichev

[permalink] [raw]
Subject: Re: [PATCH bpf V8 2/7] selftests/bpf: Add counters to xdp_hw_metadata

On 04/12, Jesper Dangaard Brouer wrote:
> Add counters for skipped, failed and redirected packets.
> The xdp_hw_metadata program only redirects UDP port 9091.
> This helps users to quickly identify then packets are
> skipped and identify failures of bpf_xdp_adjust_meta.
>
> Signed-off-by: Jesper Dangaard Brouer <[email protected]>
> ---
> .../testing/selftests/bpf/progs/xdp_hw_metadata.c | 15 +++++++++++++--
> tools/testing/selftests/bpf/xdp_hw_metadata.c | 4 +++-
> 2 files changed, 16 insertions(+), 3 deletions(-)
>
> diff --git a/tools/testing/selftests/bpf/progs/xdp_hw_metadata.c b/tools/testing/selftests/bpf/progs/xdp_hw_metadata.c
> index b0104763405a..a07ef7534013 100644
> --- a/tools/testing/selftests/bpf/progs/xdp_hw_metadata.c
> +++ b/tools/testing/selftests/bpf/progs/xdp_hw_metadata.c
> @@ -25,6 +25,10 @@ struct {
> __type(value, __u32);
> } xsk SEC(".maps");
>
> +volatile __u64 pkts_skip = 0;
> +volatile __u64 pkts_fail = 0;
> +volatile __u64 pkts_redir = 0;
> +
> extern int bpf_xdp_metadata_rx_timestamp(const struct xdp_md *ctx,
> __u64 *timestamp) __ksym;
> extern int bpf_xdp_metadata_rx_hash(const struct xdp_md *ctx,
> @@ -59,16 +63,21 @@ int rx(struct xdp_md *ctx)
> udp = NULL;
> }
>
> - if (!udp)
> + if (!udp) {
> + pkts_skip++;
> return XDP_PASS;
> + }
>
> /* Forwarding UDP:9091 to AF_XDP */
> - if (udp->dest != bpf_htons(9091))
> + if (udp->dest != bpf_htons(9091)) {
> + pkts_skip++;
> return XDP_PASS;
> + }
>
> ret = bpf_xdp_adjust_meta(ctx, -(int)sizeof(struct xdp_meta));
> if (ret != 0) {

[..]

> bpf_printk("bpf_xdp_adjust_meta returned %d", ret);

Maybe let's remove these completely? Merge patch 1 and 2, remove printk,
add counters. We can add more counters in the future if the existing
ones are not enough.. WDYT?

> + pkts_fail++;
> return XDP_PASS;
> }
>
> @@ -78,6 +87,7 @@ int rx(struct xdp_md *ctx)
>
> if (meta + 1 > data) {
> bpf_printk("bpf_xdp_adjust_meta doesn't appear to work");
> + pkts_fail++;
> return XDP_PASS;
> }
>
> @@ -91,6 +101,7 @@ int rx(struct xdp_md *ctx)
> else
> meta->rx_hash = 0; /* Used by AF_XDP as not avail signal */
>
> + pkts_redir++;
> return bpf_redirect_map(&xsk, ctx->rx_queue_index, XDP_PASS);
> }
>
> diff --git a/tools/testing/selftests/bpf/xdp_hw_metadata.c b/tools/testing/selftests/bpf/xdp_hw_metadata.c
> index 1c8acb68b977..3b942ef7297b 100644
> --- a/tools/testing/selftests/bpf/xdp_hw_metadata.c
> +++ b/tools/testing/selftests/bpf/xdp_hw_metadata.c
> @@ -212,7 +212,9 @@ static int verify_metadata(struct xsk *rx_xsk, int rxq, int server_fd)
> while (true) {
> errno = 0;
> ret = poll(fds, rxq + 1, 1000);
> - printf("poll: %d (%d)\n", ret, errno);
> + printf("poll: %d (%d) skip=%llu fail=%llu redir=%llu\n",
> + ret, errno, bpf_obj->bss->pkts_skip,
> + bpf_obj->bss->pkts_fail, bpf_obj->bss->pkts_redir);
> if (ret < 0)
> break;
> if (ret == 0)
>
>

2023-04-12 18:03:19

by Jesper Dangaard Brouer

[permalink] [raw]
Subject: Re: [PATCH bpf V8 2/7] selftests/bpf: Add counters to xdp_hw_metadata


On 12/04/2023 18.56, Stanislav Fomichev wrote:
> On 04/12, Jesper Dangaard Brouer wrote:
>> Add counters for skipped, failed and redirected packets.
>> The xdp_hw_metadata program only redirects UDP port 9091.
>> This helps users to quickly identify then packets are
>> skipped and identify failures of bpf_xdp_adjust_meta.
>>
>> Signed-off-by: Jesper Dangaard Brouer <[email protected]>
>> ---
>> .../testing/selftests/bpf/progs/xdp_hw_metadata.c | 15 +++++++++++++--
>> tools/testing/selftests/bpf/xdp_hw_metadata.c | 4 +++-
>> 2 files changed, 16 insertions(+), 3 deletions(-)
>>
>> diff --git a/tools/testing/selftests/bpf/progs/xdp_hw_metadata.c b/tools/testing/selftests/bpf/progs/xdp_hw_metadata.c
>> index b0104763405a..a07ef7534013 100644
>> --- a/tools/testing/selftests/bpf/progs/xdp_hw_metadata.c
>> +++ b/tools/testing/selftests/bpf/progs/xdp_hw_metadata.c
>> @@ -25,6 +25,10 @@ struct {
>> __type(value, __u32);
>> } xsk SEC(".maps");
>>
>> +volatile __u64 pkts_skip = 0;
>> +volatile __u64 pkts_fail = 0;
>> +volatile __u64 pkts_redir = 0;
>> +
>> extern int bpf_xdp_metadata_rx_timestamp(const struct xdp_md *ctx,
>> __u64 *timestamp) __ksym;
>> extern int bpf_xdp_metadata_rx_hash(const struct xdp_md *ctx,
>> @@ -59,16 +63,21 @@ int rx(struct xdp_md *ctx)
>> udp = NULL;
>> }
>>
>> - if (!udp)
>> + if (!udp) {
>> + pkts_skip++;
>> return XDP_PASS;
>> + }
>>
>> /* Forwarding UDP:9091 to AF_XDP */
>> - if (udp->dest != bpf_htons(9091))
>> + if (udp->dest != bpf_htons(9091)) {
>> + pkts_skip++;
>> return XDP_PASS;
>> + }
>>
>> ret = bpf_xdp_adjust_meta(ctx, -(int)sizeof(struct xdp_meta));
>> if (ret != 0) {
>
> [..]
>
>> bpf_printk("bpf_xdp_adjust_meta returned %d", ret);
>
> Maybe let's remove these completely? Merge patch 1 and 2, remove printk,
> add counters. We can add more counters in the future if the existing
> ones are not enough.. WDYT?
>

Sure, lets just remove all of the bpf_printk, and add these counter instead.
Rolling V9.

>> + pkts_fail++;

This fail counter should be enough for driver devel to realize that they
also need to implement/setup XDP metadata pointers correctly (for
bpf_xdp_adjust_meta to work).

>> return XDP_PASS;
>> }

2023-04-12 18:03:43

by Stanislav Fomichev

[permalink] [raw]
Subject: Re: [PATCH bpf V8 2/7] selftests/bpf: Add counters to xdp_hw_metadata

On Wed, Apr 12, 2023 at 10:52 AM Jesper Dangaard Brouer
<[email protected]> wrote:
>
>
> On 12/04/2023 18.56, Stanislav Fomichev wrote:
> > On 04/12, Jesper Dangaard Brouer wrote:
> >> Add counters for skipped, failed and redirected packets.
> >> The xdp_hw_metadata program only redirects UDP port 9091.
> >> This helps users to quickly identify then packets are
> >> skipped and identify failures of bpf_xdp_adjust_meta.
> >>
> >> Signed-off-by: Jesper Dangaard Brouer <[email protected]>
> >> ---
> >> .../testing/selftests/bpf/progs/xdp_hw_metadata.c | 15 +++++++++++++--
> >> tools/testing/selftests/bpf/xdp_hw_metadata.c | 4 +++-
> >> 2 files changed, 16 insertions(+), 3 deletions(-)
> >>
> >> diff --git a/tools/testing/selftests/bpf/progs/xdp_hw_metadata.c b/tools/testing/selftests/bpf/progs/xdp_hw_metadata.c
> >> index b0104763405a..a07ef7534013 100644
> >> --- a/tools/testing/selftests/bpf/progs/xdp_hw_metadata.c
> >> +++ b/tools/testing/selftests/bpf/progs/xdp_hw_metadata.c
> >> @@ -25,6 +25,10 @@ struct {
> >> __type(value, __u32);
> >> } xsk SEC(".maps");
> >>
> >> +volatile __u64 pkts_skip = 0;
> >> +volatile __u64 pkts_fail = 0;
> >> +volatile __u64 pkts_redir = 0;
> >> +
> >> extern int bpf_xdp_metadata_rx_timestamp(const struct xdp_md *ctx,
> >> __u64 *timestamp) __ksym;
> >> extern int bpf_xdp_metadata_rx_hash(const struct xdp_md *ctx,
> >> @@ -59,16 +63,21 @@ int rx(struct xdp_md *ctx)
> >> udp = NULL;
> >> }
> >>
> >> - if (!udp)
> >> + if (!udp) {
> >> + pkts_skip++;
> >> return XDP_PASS;
> >> + }
> >>
> >> /* Forwarding UDP:9091 to AF_XDP */
> >> - if (udp->dest != bpf_htons(9091))
> >> + if (udp->dest != bpf_htons(9091)) {
> >> + pkts_skip++;
> >> return XDP_PASS;
> >> + }
> >>
> >> ret = bpf_xdp_adjust_meta(ctx, -(int)sizeof(struct xdp_meta));
> >> if (ret != 0) {
> >
> > [..]
> >
> >> bpf_printk("bpf_xdp_adjust_meta returned %d", ret);
> >
> > Maybe let's remove these completely? Merge patch 1 and 2, remove printk,
> > add counters. We can add more counters in the future if the existing
> > ones are not enough.. WDYT?
> >
>
> Sure, lets just remove all of the bpf_printk, and add these counter instead.
> Rolling V9.
>
> >> + pkts_fail++;
>
> This fail counter should be enough for driver devel to realize that they
> also need to implement/setup XDP metadata pointers correctly (for
> bpf_xdp_adjust_meta to work).

Agreed. As long as we have a clear signal "something's not working"
(instead of failing silently), that should be enough to get to the
bottom of it..

> >> return XDP_PASS;
> >> }
>