[xdp-hints] [PATCH RFC bpf-next 18/52] samples/bpf: add ability to specify metadata threshold

[Alexander Lobakin <alexandr.lobakin@intel.com>]

For all of the users of sample_install_xdp() infra (primarily for
xdp_redirect_cpu), add the ability to enable/disable/control generic
metadata generation using the new UAPI.
The format is either just '-M' to enable it unconditionally or
'--meta-thresh=<frame_size>' to enable it starting from frames
bigger than <frame_size>.

Signed-off-by: Alexander Lobakin <alexandr.lobakin@intel.com>
---
 samples/bpf/xdp_redirect_cpu_user.c       |  7 +++++-
 samples/bpf/xdp_redirect_map_multi_user.c |  7 +++++-
 samples/bpf/xdp_redirect_map_user.c       |  7 +++++-
 samples/bpf/xdp_redirect_user.c           |  6 ++++-
 samples/bpf/xdp_router_ipv4_user.c        |  7 +++++-
 samples/bpf/xdp_sample_user.c             | 28 +++++++++++++++++++----
 samples/bpf/xdp_sample_user.h             |  1 +
 7 files changed, 53 insertions(+), 10 deletions(-)

diff --git a/samples/bpf/xdp_redirect_cpu_user.c b/samples/bpf/xdp_redirect_cpu_user.c
index 15745d8cb5c2..ca457c34eb0f 100644
--- a/samples/bpf/xdp_redirect_cpu_user.c
+++ b/samples/bpf/xdp_redirect_cpu_user.c
@@ -60,6 +60,7 @@ static const struct option long_options[] = {
 	{ "mprog-filename", required_argument, NULL, 'f' },
 	{ "redirect-device", required_argument, NULL, 'r' },
 	{ "redirect-map", required_argument, NULL, 'm' },
+	{ "meta-thresh", optional_argument, NULL, 'M' },
 	{}
 };
 
@@ -382,7 +383,7 @@ int main(int argc, char **argv)
 	}
 
 	prog = skel->progs.xdp_prognum5_lb_hash_ip_pairs;
-	while ((opt = getopt_long(argc, argv, "d:si:Sxp:f:e:r:m:c:q:Fvh",
+	while ((opt = getopt_long(argc, argv, "d:si:Sxp:f:e:r:m:c:q:FMvh",
 				  long_options, &longindex)) != -1) {
 		switch (opt) {
 		case 'd':
@@ -461,6 +462,10 @@ int main(int argc, char **argv)
 		case 'v':
 			sample_switch_mode();
 			break;
+		case 'M':
+			opts.meta_thresh = optarg ? strtoul(optarg, NULL, 0) :
+					   1;
+			break;
 		case 'h':
 			error = false;
 		default:
diff --git a/samples/bpf/xdp_redirect_map_multi_user.c b/samples/bpf/xdp_redirect_map_multi_user.c
index 85e66f9dc259..b1c575f3d5f6 100644
--- a/samples/bpf/xdp_redirect_map_multi_user.c
+++ b/samples/bpf/xdp_redirect_map_multi_user.c
@@ -43,6 +43,7 @@ static const struct option long_options[] = {
 	{ "stats", no_argument, NULL, 's' },
 	{ "interval", required_argument, NULL, 'i' },
 	{ "verbose", no_argument, NULL, 'v' },
+	{ "meta-thresh", optional_argument, NULL, 'M' },
 	{}
 };
 
@@ -89,7 +90,7 @@ int main(int argc, char **argv)
 	bool error = true;
 	int i, opt;
 
-	while ((opt = getopt_long(argc, argv, "hSFXi:vs",
+	while ((opt = getopt_long(argc, argv, "hSFMXi:vs",
 				  long_options, NULL)) != -1) {
 		switch (opt) {
 		case 'S':
@@ -98,6 +99,10 @@ int main(int argc, char **argv)
 			mask &= ~(SAMPLE_DEVMAP_XMIT_CNT |
 				  SAMPLE_DEVMAP_XMIT_CNT_MULTI);
 			break;
+		case 'M':
+			opts.meta_thresh = optarg ? strtoul(optarg, NULL, 0) :
+					   1;
+			break;
 		case 'F':
 			opts.force = true;
 			break;
diff --git a/samples/bpf/xdp_redirect_map_user.c b/samples/bpf/xdp_redirect_map_user.c
index d09ef866e62b..29dd7df804dc 100644
--- a/samples/bpf/xdp_redirect_map_user.c
+++ b/samples/bpf/xdp_redirect_map_user.c
@@ -37,6 +37,7 @@ static const struct option long_options[] = {
 	{ "stats", no_argument, NULL, 's' },
 	{ "interval", required_argument, NULL, 'i' },
 	{ "verbose", no_argument, NULL, 'v' },
+	{ "meta-thresh", optional_argument, NULL, 'M' },
 	{}
 };
 
@@ -58,7 +59,7 @@ int main(int argc, char **argv)
 	bool error = true;
 	int opt, key = 0;
 
-	while ((opt = getopt_long(argc, argv, "hSFXi:vs",
+	while ((opt = getopt_long(argc, argv, "hSFMXi:vs",
 				  long_options, NULL)) != -1) {
 		switch (opt) {
 		case 'S':
@@ -67,6 +68,10 @@ int main(int argc, char **argv)
 			mask &= ~(SAMPLE_DEVMAP_XMIT_CNT |
 				  SAMPLE_DEVMAP_XMIT_CNT_MULTI);
 			break;
+		case 'M':
+			opts.meta_thresh = optarg ? strtoul(optarg, NULL, 0) :
+					   1;
+			break;
 		case 'F':
 			opts.force = true;
 			break;
diff --git a/samples/bpf/xdp_redirect_user.c b/samples/bpf/xdp_redirect_user.c
index 2da686a9b8a0..f37c570877ca 100644
--- a/samples/bpf/xdp_redirect_user.c
+++ b/samples/bpf/xdp_redirect_user.c
@@ -36,6 +36,7 @@ static const struct option long_options[] = {
 	{"stats",	no_argument,		NULL, 's' },
 	{"interval",	required_argument,	NULL, 'i' },
 	{"verbose",	no_argument,		NULL, 'v' },
+	{"meta-thresh",	optional_argument,	NULL, 'M' },
 	{}
 };
 
@@ -51,7 +52,7 @@ int main(int argc, char **argv)
 	struct xdp_redirect *skel;
 	bool error = true;
 
-	while ((opt = getopt_long(argc, argv, "hSFi:vs",
+	while ((opt = getopt_long(argc, argv, "hSFMi:vs",
 				  long_options, NULL)) != -1) {
 		switch (opt) {
 		case 'S':
@@ -59,6 +60,9 @@ int main(int argc, char **argv)
 			mask &= ~(SAMPLE_DEVMAP_XMIT_CNT |
 				  SAMPLE_DEVMAP_XMIT_CNT_MULTI);
 			break;
+		case 'M':
+			opts.meta_thresh = optarg ? strtoul(optarg, NULL, 0) :
+					   1;
 		case 'F':
 			opts.force = true;
 			break;
diff --git a/samples/bpf/xdp_router_ipv4_user.c b/samples/bpf/xdp_router_ipv4_user.c
index 48e9bcb38c8e..5ff12688a31b 100644
--- a/samples/bpf/xdp_router_ipv4_user.c
+++ b/samples/bpf/xdp_router_ipv4_user.c
@@ -53,6 +53,7 @@ static const struct option long_options[] = {
 	{ "interval", required_argument, NULL, 'i' },
 	{ "verbose", no_argument, NULL, 'v' },
 	{ "stats", no_argument, NULL, 's' },
+	{ "meta-thresh", optional_argument, NULL, 'M' },
 	{}
 };
 
@@ -593,7 +594,7 @@ int main(int argc, char **argv)
 		goto end_destroy;
 	}
 
-	while ((opt = getopt_long(argc, argv, "si:SFvh",
+	while ((opt = getopt_long(argc, argv, "si:SFMvh",
 				  long_options, &longindex)) != -1) {
 		switch (opt) {
 		case 's':
@@ -621,6 +622,10 @@ int main(int argc, char **argv)
 			total_ifindex--;
 			ifname_list++;
 			break;
+		case 'M':
+			opts.meta_thresh = optarg ? strtoul(optarg, NULL, 0) :
+					   1;
+			break;
 		case 'h':
 			error = false;
 		default:
diff --git a/samples/bpf/xdp_sample_user.c b/samples/bpf/xdp_sample_user.c
index 8bc23b4c5f19..354352541c5e 100644
--- a/samples/bpf/xdp_sample_user.c
+++ b/samples/bpf/xdp_sample_user.c
@@ -1283,6 +1283,8 @@ static int __sample_remove_xdp(int ifindex, __u32 prog_id, int xdp_flags)
 int sample_install_xdp(struct bpf_program *xdp_prog,
 		       const struct sample_install_opts *opts)
 {
+	LIBBPF_OPTS(bpf_xdp_attach_opts, attach_opts,
+		    .meta_thresh = opts->meta_thresh);
 	__u32 ifindex = opts->ifindex;
 	int ret, xdp_flags = 0;
 	__u32 prog_id = 0;
@@ -1293,18 +1295,34 @@ int sample_install_xdp(struct bpf_program *xdp_prog,
 		return -ENOTSUP;
 	}
 
+	if (attach_opts.meta_thresh) {
+		ret = libbpf_get_type_btf_id("struct xdp_meta_generic",
+					     &attach_opts.btf_id);
+		if (ret) {
+			fprintf(stderr, "Failed to retrieve BTF ID: %s\n",
+				strerror(-ret));
+			return ret;
+		}
+	}
+
 	xdp_flags |= !opts->force ? XDP_FLAGS_UPDATE_IF_NOEXIST : 0;
 	xdp_flags |= opts->generic ? XDP_FLAGS_SKB_MODE : XDP_FLAGS_DRV_MODE;
-	ret = bpf_xdp_attach(ifindex, bpf_program__fd(xdp_prog), xdp_flags, NULL);
+	ret = bpf_xdp_attach(ifindex, bpf_program__fd(xdp_prog), xdp_flags,
+			     &attach_opts);
 	if (ret < 0) {
 		ret = -errno;
 		fprintf(stderr,
-			"Failed to install program \"%s\" on ifindex %d, mode = %s, "
-			"force = %s: %s\n",
+			"Failed to install program \"%s\" on ifindex %d, mode = %s, force = %s, metadata = ",
 			bpf_program__name(xdp_prog), ifindex,
 			opts->generic ? "skb" : "native",
-			opts->force ? "true" : "false",
-			strerror(-ret));
+			opts->force ? "true" : "false");
+		if (attach_opts.meta_thresh)
+			fprintf(stderr,
+				"true (from %u bytes, BTF ID is 0x%16llx)",
+				attach_opts.meta_thresh, attach_opts.btf_id);
+		else
+			fprintf(stderr, "false");
+		fprintf(stderr, ": %s\n", strerror(-ret));
 		return ret;
 	}
 
diff --git a/samples/bpf/xdp_sample_user.h b/samples/bpf/xdp_sample_user.h
index 22afe844ae30..207953406ee1 100644
--- a/samples/bpf/xdp_sample_user.h
+++ b/samples/bpf/xdp_sample_user.h
@@ -34,6 +34,7 @@ struct sample_install_opts {
 	int ifindex;
 	__u32 force:1;
 	__u32 generic:1;
+	__u32 meta_thresh;
 };
 
 int sample_setup_maps(struct bpf_map **maps);
-- 
2.36.1