diff mbox series

[External,bpf-next,v6,3/3] selftests/bpf: Replace bpf_trace_printk in tunnel kernel code

Message ID 20220430074844.69214-4-fankaixi.li@bytedance.com (mailing list archive)
State Accepted
Commit 71b2ec21c3313e4cea38d5a6b009e99df30e540a
Delegated to: BPF
Headers show
Series Add source ip in bpf tunnel key | expand

Checks

Context Check Description
netdev/tree_selection success Clearly marked for bpf-next, async
netdev/fixes_present success Fixes tag not required for -next series
netdev/subject_prefix success Link
netdev/cover_letter success Series has a cover letter
netdev/patch_count success Link
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 0 this patch: 0
netdev/cc_maintainers warning 4 maintainers not CCed: linux-kselftest@vger.kernel.org shuah@kernel.org davemarchevsky@fb.com netdev@vger.kernel.org
netdev/build_clang success Errors and warnings before: 0 this patch: 0
netdev/module_param success Was 0 now: 0
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 0 this patch: 0
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 507 lines checked
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0
bpf/vmtest-bpf-next-PR success PR summary
bpf/vmtest-bpf-next-VM_Test-1 success Logs for Kernel LATEST on ubuntu-latest + selftests
bpf/vmtest-bpf-next-VM_Test-2 success Logs for Kernel LATEST on z15 + selftests

Commit Message

Kaixi Fan April 30, 2022, 7:48 a.m. UTC 
From: Kaixi Fan <fankaixi.li@bytedance.com>

Replace bpf_trace_printk with bpf_printk in test_tunnel_kern.c.
function bpf_printk is more easier and useful than bpf_trace_printk.

Signed-off-by: Kaixi Fan <fankaixi.li@bytedance.com>
---
 .../selftests/bpf/progs/test_tunnel_kern.c    | 169 ++++++++----------
 1 file changed, 72 insertions(+), 97 deletions(-)
diff mbox series

Patch

diff --git a/tools/testing/selftests/bpf/progs/test_tunnel_kern.c b/tools/testing/selftests/bpf/progs/test_tunnel_kern.c
index b33ceff2f74d..17f2f325b3f3 100644
--- a/tools/testing/selftests/bpf/progs/test_tunnel_kern.c
+++ b/tools/testing/selftests/bpf/progs/test_tunnel_kern.c
@@ -21,10 +21,7 @@ 
 #include <bpf/bpf_helpers.h>
 #include <bpf/bpf_endian.h>
 
-#define ERROR(ret) do {\
-		char fmt[] = "ERROR line:%d ret:%d\n";\
-		bpf_trace_printk(fmt, sizeof(fmt), __LINE__, ret); \
-	} while (0)
+#define log_err(__ret) bpf_printk("ERROR line:%d ret:%d\n", __LINE__, __ret)
 
 struct geneve_opt {
 	__be16	opt_class;
@@ -47,7 +44,6 @@  struct {
 	__type(value, __u32);
 } local_ip_map SEC(".maps");
 
-
 SEC("tc")
 int gre_set_tunnel(struct __sk_buff *skb)
 {
@@ -63,7 +59,7 @@  int gre_set_tunnel(struct __sk_buff *skb)
 	ret = bpf_skb_set_tunnel_key(skb, &key, sizeof(key),
 				     BPF_F_ZERO_CSUM_TX | BPF_F_SEQ_NUMBER);
 	if (ret < 0) {
-		ERROR(ret);
+		log_err(ret);
 		return TC_ACT_SHOT;
 	}
 
@@ -75,15 +71,14 @@  int gre_get_tunnel(struct __sk_buff *skb)
 {
 	int ret;
 	struct bpf_tunnel_key key;
-	char fmt[] = "key %d remote ip 0x%x\n";
 
 	ret = bpf_skb_get_tunnel_key(skb, &key, sizeof(key), 0);
 	if (ret < 0) {
-		ERROR(ret);
+		log_err(ret);
 		return TC_ACT_SHOT;
 	}
 
-	bpf_trace_printk(fmt, sizeof(fmt), key.tunnel_id, key.remote_ipv4);
+	bpf_printk("key %d remote ip 0x%x\n", key.tunnel_id, key.remote_ipv4);
 	return TC_ACT_OK;
 }
 
@@ -104,7 +99,7 @@  int ip6gretap_set_tunnel(struct __sk_buff *skb)
 				     BPF_F_TUNINFO_IPV6 | BPF_F_ZERO_CSUM_TX |
 				     BPF_F_SEQ_NUMBER);
 	if (ret < 0) {
-		ERROR(ret);
+		log_err(ret);
 		return TC_ACT_SHOT;
 	}
 
@@ -114,19 +109,18 @@  int ip6gretap_set_tunnel(struct __sk_buff *skb)
 SEC("tc")
 int ip6gretap_get_tunnel(struct __sk_buff *skb)
 {
-	char fmt[] = "key %d remote ip6 ::%x label %x\n";
 	struct bpf_tunnel_key key;
 	int ret;
 
 	ret = bpf_skb_get_tunnel_key(skb, &key, sizeof(key),
 				     BPF_F_TUNINFO_IPV6);
 	if (ret < 0) {
-		ERROR(ret);
+		log_err(ret);
 		return TC_ACT_SHOT;
 	}
 
-	bpf_trace_printk(fmt, sizeof(fmt),
-			 key.tunnel_id, key.remote_ipv6[3], key.tunnel_label);
+	bpf_printk("key %d remote ip6 ::%x label %x\n",
+		   key.tunnel_id, key.remote_ipv6[3], key.tunnel_label);
 
 	return TC_ACT_OK;
 }
@@ -147,7 +141,7 @@  int erspan_set_tunnel(struct __sk_buff *skb)
 	ret = bpf_skb_set_tunnel_key(skb, &key, sizeof(key),
 				     BPF_F_ZERO_CSUM_TX);
 	if (ret < 0) {
-		ERROR(ret);
+		log_err(ret);
 		return TC_ACT_SHOT;
 	}
 
@@ -167,7 +161,7 @@  int erspan_set_tunnel(struct __sk_buff *skb)
 
 	ret = bpf_skb_set_tunnel_opt(skb, &md, sizeof(md));
 	if (ret < 0) {
-		ERROR(ret);
+		log_err(ret);
 		return TC_ACT_SHOT;
 	}
 
@@ -177,7 +171,6 @@  int erspan_set_tunnel(struct __sk_buff *skb)
 SEC("tc")
 int erspan_get_tunnel(struct __sk_buff *skb)
 {
-	char fmt[] = "key %d remote ip 0x%x erspan version %d\n";
 	struct bpf_tunnel_key key;
 	struct erspan_metadata md;
 	__u32 index;
@@ -185,31 +178,27 @@  int erspan_get_tunnel(struct __sk_buff *skb)
 
 	ret = bpf_skb_get_tunnel_key(skb, &key, sizeof(key), 0);
 	if (ret < 0) {
-		ERROR(ret);
+		log_err(ret);
 		return TC_ACT_SHOT;
 	}
 
 	ret = bpf_skb_get_tunnel_opt(skb, &md, sizeof(md));
 	if (ret < 0) {
-		ERROR(ret);
+		log_err(ret);
 		return TC_ACT_SHOT;
 	}
 
-	bpf_trace_printk(fmt, sizeof(fmt),
-			key.tunnel_id, key.remote_ipv4, md.version);
+	bpf_printk("key %d remote ip 0x%x erspan version %d\n",
+		   key.tunnel_id, key.remote_ipv4, md.version);
 
 #ifdef ERSPAN_V1
-	char fmt2[] = "\tindex %x\n";
-
 	index = bpf_ntohl(md.u.index);
-	bpf_trace_printk(fmt2, sizeof(fmt2), index);
+	bpf_printk("\tindex %x\n", index);
 #else
-	char fmt2[] = "\tdirection %d hwid %x timestamp %u\n";
-
-	bpf_trace_printk(fmt2, sizeof(fmt2),
-			 md.u.md2.dir,
-			 (md.u.md2.hwid_upper << 4) + md.u.md2.hwid,
-			 bpf_ntohl(md.u.md2.timestamp));
+	bpf_printk("\tdirection %d hwid %x timestamp %u\n",
+		   md.u.md2.dir,
+		   (md.u.md2.hwid_upper << 4) + md.u.md2.hwid,
+		   bpf_ntohl(md.u.md2.timestamp));
 #endif
 
 	return TC_ACT_OK;
@@ -231,7 +220,7 @@  int ip4ip6erspan_set_tunnel(struct __sk_buff *skb)
 	ret = bpf_skb_set_tunnel_key(skb, &key, sizeof(key),
 				     BPF_F_TUNINFO_IPV6);
 	if (ret < 0) {
-		ERROR(ret);
+		log_err(ret);
 		return TC_ACT_SHOT;
 	}
 
@@ -252,7 +241,7 @@  int ip4ip6erspan_set_tunnel(struct __sk_buff *skb)
 
 	ret = bpf_skb_set_tunnel_opt(skb, &md, sizeof(md));
 	if (ret < 0) {
-		ERROR(ret);
+		log_err(ret);
 		return TC_ACT_SHOT;
 	}
 
@@ -262,7 +251,6 @@  int ip4ip6erspan_set_tunnel(struct __sk_buff *skb)
 SEC("tc")
 int ip4ip6erspan_get_tunnel(struct __sk_buff *skb)
 {
-	char fmt[] = "ip6erspan get key %d remote ip6 ::%x erspan version %d\n";
 	struct bpf_tunnel_key key;
 	struct erspan_metadata md;
 	__u32 index;
@@ -271,31 +259,27 @@  int ip4ip6erspan_get_tunnel(struct __sk_buff *skb)
 	ret = bpf_skb_get_tunnel_key(skb, &key, sizeof(key),
 				     BPF_F_TUNINFO_IPV6);
 	if (ret < 0) {
-		ERROR(ret);
+		log_err(ret);
 		return TC_ACT_SHOT;
 	}
 
 	ret = bpf_skb_get_tunnel_opt(skb, &md, sizeof(md));
 	if (ret < 0) {
-		ERROR(ret);
+		log_err(ret);
 		return TC_ACT_SHOT;
 	}
 
-	bpf_trace_printk(fmt, sizeof(fmt),
-			key.tunnel_id, key.remote_ipv4, md.version);
+	bpf_printk("ip6erspan get key %d remote ip6 ::%x erspan version %d\n",
+		   key.tunnel_id, key.remote_ipv4, md.version);
 
 #ifdef ERSPAN_V1
-	char fmt2[] = "\tindex %x\n";
-
 	index = bpf_ntohl(md.u.index);
-	bpf_trace_printk(fmt2, sizeof(fmt2), index);
+	bpf_printk("\tindex %x\n", index);
 #else
-	char fmt2[] = "\tdirection %d hwid %x timestamp %u\n";
-
-	bpf_trace_printk(fmt2, sizeof(fmt2),
-			 md.u.md2.dir,
-			 (md.u.md2.hwid_upper << 4) + md.u.md2.hwid,
-			 bpf_ntohl(md.u.md2.timestamp));
+	bpf_printk("\tdirection %d hwid %x timestamp %u\n",
+		   md.u.md2.dir,
+		   (md.u.md2.hwid_upper << 4) + md.u.md2.hwid,
+		   bpf_ntohl(md.u.md2.timestamp));
 #endif
 
 	return TC_ACT_OK;
@@ -351,7 +335,7 @@  int vxlan_set_tunnel_src(struct __sk_buff *skb)
 
 	local_ip = bpf_map_lookup_elem(&local_ip_map, &index);
 	if (!local_ip) {
-		ERROR(ret);
+		log_err(ret);
 		return TC_ACT_SHOT;
 	}
 
@@ -365,14 +349,14 @@  int vxlan_set_tunnel_src(struct __sk_buff *skb)
 	ret = bpf_skb_set_tunnel_key(skb, &key, sizeof(key),
 				     BPF_F_ZERO_CSUM_TX);
 	if (ret < 0) {
-		ERROR(ret);
+		log_err(ret);
 		return TC_ACT_SHOT;
 	}
 
 	md.gbp = 0x800FF; /* Set VXLAN Group Policy extension */
 	ret = bpf_skb_set_tunnel_opt(skb, &md, sizeof(md));
 	if (ret < 0) {
-		ERROR(ret);
+		log_err(ret);
 		return TC_ACT_SHOT;
 	}
 
@@ -385,26 +369,24 @@  int vxlan_get_tunnel_src(struct __sk_buff *skb)
 	int ret;
 	struct bpf_tunnel_key key;
 	struct vxlan_metadata md;
-	char fmt[] = "key %d remote ip 0x%x vxlan gbp 0x%x\n";
-	char fmt2[] = "local ip 0x%x\n";
 	__u32 index = 0;
 	__u32 *local_ip = NULL;
 
 	local_ip = bpf_map_lookup_elem(&local_ip_map, &index);
 	if (!local_ip) {
-		ERROR(ret);
+		log_err(ret);
 		return TC_ACT_SHOT;
 	}
 
 	ret = bpf_skb_get_tunnel_key(skb, &key, sizeof(key), 0);
 	if (ret < 0) {
-		ERROR(ret);
+		log_err(ret);
 		return TC_ACT_SHOT;
 	}
 
 	ret = bpf_skb_get_tunnel_opt(skb, &md, sizeof(md));
 	if (ret < 0) {
-		ERROR(ret);
+		log_err(ret);
 		return TC_ACT_SHOT;
 	}
 
@@ -461,7 +443,7 @@  int ip6vxlan_set_tunnel_src(struct __sk_buff *skb)
 
 	local_ip = bpf_map_lookup_elem(&local_ip_map, &index);
 	if (!local_ip) {
-		ERROR(ret);
+		log_err(ret);
 		return TC_ACT_SHOT;
 	}
 
@@ -475,7 +457,7 @@  int ip6vxlan_set_tunnel_src(struct __sk_buff *skb)
 	ret = bpf_skb_set_tunnel_key(skb, &key, sizeof(key),
 				     BPF_F_TUNINFO_IPV6);
 	if (ret < 0) {
-		ERROR(ret);
+		log_err(ret);
 		return TC_ACT_SHOT;
 	}
 
@@ -485,8 +467,6 @@  int ip6vxlan_set_tunnel_src(struct __sk_buff *skb)
 SEC("tc")
 int ip6vxlan_get_tunnel_src(struct __sk_buff *skb)
 {
-	char fmt[] = "key %d remote ip6 ::%x label %x\n";
-	char fmt2[] = "local ip6 ::%x\n";
 	struct bpf_tunnel_key key;
 	int ret;
 	__u32 index = 0;
@@ -494,23 +474,23 @@  int ip6vxlan_get_tunnel_src(struct __sk_buff *skb)
 
 	local_ip = bpf_map_lookup_elem(&local_ip_map, &index);
 	if (!local_ip) {
-		ERROR(ret);
+		log_err(ret);
 		return TC_ACT_SHOT;
 	}
 
 	ret = bpf_skb_get_tunnel_key(skb, &key, sizeof(key),
 				     BPF_F_TUNINFO_IPV6);
 	if (ret < 0) {
-		ERROR(ret);
+		log_err(ret);
 		return TC_ACT_SHOT;
 	}
 
 	if (bpf_ntohl(key.local_ipv6[3]) != *local_ip) {
-		bpf_trace_printk(fmt, sizeof(fmt),
-				 key.tunnel_id,
-				 key.remote_ipv6[3], key.tunnel_label);
-		bpf_trace_printk(fmt2, sizeof(fmt2), key.local_ipv6[3]);
-		ERROR(ret);
+		bpf_printk("ip6vxlan key %d local ip6 ::%x remote ip6 ::%x label 0x%x\n",
+			   key.tunnel_id, bpf_ntohl(key.local_ipv6[3]),
+			   bpf_ntohl(key.remote_ipv6[3]), key.tunnel_label);
+		bpf_printk("local_ip 0x%x\n", *local_ip);
+		log_err(ret);
 		return TC_ACT_SHOT;
 	}
 
@@ -542,13 +522,13 @@  int geneve_set_tunnel(struct __sk_buff *skb)
 	ret = bpf_skb_set_tunnel_key(skb, &key, sizeof(key),
 				     BPF_F_ZERO_CSUM_TX);
 	if (ret < 0) {
-		ERROR(ret);
+		log_err(ret);
 		return TC_ACT_SHOT;
 	}
 
 	ret = bpf_skb_set_tunnel_opt(skb, &gopt, sizeof(gopt));
 	if (ret < 0) {
-		ERROR(ret);
+		log_err(ret);
 		return TC_ACT_SHOT;
 	}
 
@@ -561,11 +541,10 @@  int geneve_get_tunnel(struct __sk_buff *skb)
 	int ret;
 	struct bpf_tunnel_key key;
 	struct geneve_opt gopt;
-	char fmt[] = "key %d remote ip 0x%x geneve class 0x%x\n";
 
 	ret = bpf_skb_get_tunnel_key(skb, &key, sizeof(key), 0);
 	if (ret < 0) {
-		ERROR(ret);
+		log_err(ret);
 		return TC_ACT_SHOT;
 	}
 
@@ -573,8 +552,8 @@  int geneve_get_tunnel(struct __sk_buff *skb)
 	if (ret < 0)
 		gopt.opt_class = 0;
 
-	bpf_trace_printk(fmt, sizeof(fmt),
-			key.tunnel_id, key.remote_ipv4, gopt.opt_class);
+	bpf_printk("key %d remote ip 0x%x geneve class 0x%x\n",
+		   key.tunnel_id, key.remote_ipv4, gopt.opt_class);
 	return TC_ACT_OK;
 }
 
@@ -594,7 +573,7 @@  int ip6geneve_set_tunnel(struct __sk_buff *skb)
 	ret = bpf_skb_set_tunnel_key(skb, &key, sizeof(key),
 				     BPF_F_TUNINFO_IPV6);
 	if (ret < 0) {
-		ERROR(ret);
+		log_err(ret);
 		return TC_ACT_SHOT;
 	}
 
@@ -609,7 +588,7 @@  int ip6geneve_set_tunnel(struct __sk_buff *skb)
 
 	ret = bpf_skb_set_tunnel_opt(skb, &gopt, sizeof(gopt));
 	if (ret < 0) {
-		ERROR(ret);
+		log_err(ret);
 		return TC_ACT_SHOT;
 	}
 
@@ -619,7 +598,6 @@  int ip6geneve_set_tunnel(struct __sk_buff *skb)
 SEC("tc")
 int ip6geneve_get_tunnel(struct __sk_buff *skb)
 {
-	char fmt[] = "key %d remote ip 0x%x geneve class 0x%x\n";
 	struct bpf_tunnel_key key;
 	struct geneve_opt gopt;
 	int ret;
@@ -627,7 +605,7 @@  int ip6geneve_get_tunnel(struct __sk_buff *skb)
 	ret = bpf_skb_get_tunnel_key(skb, &key, sizeof(key),
 				     BPF_F_TUNINFO_IPV6);
 	if (ret < 0) {
-		ERROR(ret);
+		log_err(ret);
 		return TC_ACT_SHOT;
 	}
 
@@ -635,8 +613,8 @@  int ip6geneve_get_tunnel(struct __sk_buff *skb)
 	if (ret < 0)
 		gopt.opt_class = 0;
 
-	bpf_trace_printk(fmt, sizeof(fmt),
-			key.tunnel_id, key.remote_ipv4, gopt.opt_class);
+	bpf_printk("key %d remote ip 0x%x geneve class 0x%x\n",
+		   key.tunnel_id, key.remote_ipv4, gopt.opt_class);
 
 	return TC_ACT_OK;
 }
@@ -652,7 +630,7 @@  int ipip_set_tunnel(struct __sk_buff *skb)
 
 	/* single length check */
 	if (data + sizeof(*iph) > data_end) {
-		ERROR(1);
+		log_err(1);
 		return TC_ACT_SHOT;
 	}
 
@@ -663,7 +641,7 @@  int ipip_set_tunnel(struct __sk_buff *skb)
 
 	ret = bpf_skb_set_tunnel_key(skb, &key, sizeof(key), 0);
 	if (ret < 0) {
-		ERROR(ret);
+		log_err(ret);
 		return TC_ACT_SHOT;
 	}
 
@@ -675,15 +653,14 @@  int ipip_get_tunnel(struct __sk_buff *skb)
 {
 	int ret;
 	struct bpf_tunnel_key key;
-	char fmt[] = "remote ip 0x%x\n";
 
 	ret = bpf_skb_get_tunnel_key(skb, &key, sizeof(key), 0);
 	if (ret < 0) {
-		ERROR(ret);
+		log_err(ret);
 		return TC_ACT_SHOT;
 	}
 
-	bpf_trace_printk(fmt, sizeof(fmt), key.remote_ipv4);
+	bpf_printk("remote ip 0x%x\n", key.remote_ipv4);
 	return TC_ACT_OK;
 }
 
@@ -698,7 +675,7 @@  int ipip6_set_tunnel(struct __sk_buff *skb)
 
 	/* single length check */
 	if (data + sizeof(*iph) > data_end) {
-		ERROR(1);
+		log_err(1);
 		return TC_ACT_SHOT;
 	}
 
@@ -711,7 +688,7 @@  int ipip6_set_tunnel(struct __sk_buff *skb)
 	ret = bpf_skb_set_tunnel_key(skb, &key, sizeof(key),
 				     BPF_F_TUNINFO_IPV6);
 	if (ret < 0) {
-		ERROR(ret);
+		log_err(ret);
 		return TC_ACT_SHOT;
 	}
 
@@ -723,17 +700,16 @@  int ipip6_get_tunnel(struct __sk_buff *skb)
 {
 	int ret;
 	struct bpf_tunnel_key key;
-	char fmt[] = "remote ip6 %x::%x\n";
 
 	ret = bpf_skb_get_tunnel_key(skb, &key, sizeof(key),
 				     BPF_F_TUNINFO_IPV6);
 	if (ret < 0) {
-		ERROR(ret);
+		log_err(ret);
 		return TC_ACT_SHOT;
 	}
 
-	bpf_trace_printk(fmt, sizeof(fmt), bpf_htonl(key.remote_ipv6[0]),
-			 bpf_htonl(key.remote_ipv6[3]));
+	bpf_printk("remote ip6 %x::%x\n", bpf_htonl(key.remote_ipv6[0]),
+		   bpf_htonl(key.remote_ipv6[3]));
 	return TC_ACT_OK;
 }
 
@@ -748,7 +724,7 @@  int ip6ip6_set_tunnel(struct __sk_buff *skb)
 
 	/* single length check */
 	if (data + sizeof(*iph) > data_end) {
-		ERROR(1);
+		log_err(1);
 		return TC_ACT_SHOT;
 	}
 
@@ -760,7 +736,7 @@  int ip6ip6_set_tunnel(struct __sk_buff *skb)
 	ret = bpf_skb_set_tunnel_key(skb, &key, sizeof(key),
 				     BPF_F_TUNINFO_IPV6);
 	if (ret < 0) {
-		ERROR(ret);
+		log_err(ret);
 		return TC_ACT_SHOT;
 	}
 
@@ -772,17 +748,16 @@  int ip6ip6_get_tunnel(struct __sk_buff *skb)
 {
 	int ret;
 	struct bpf_tunnel_key key;
-	char fmt[] = "remote ip6 %x::%x\n";
 
 	ret = bpf_skb_get_tunnel_key(skb, &key, sizeof(key),
 				     BPF_F_TUNINFO_IPV6);
 	if (ret < 0) {
-		ERROR(ret);
+		log_err(ret);
 		return TC_ACT_SHOT;
 	}
 
-	bpf_trace_printk(fmt, sizeof(fmt), bpf_htonl(key.remote_ipv6[0]),
-			 bpf_htonl(key.remote_ipv6[3]));
+	bpf_printk("remote ip6 %x::%x\n", bpf_htonl(key.remote_ipv6[0]),
+		   bpf_htonl(key.remote_ipv6[3]));
 	return TC_ACT_OK;
 }
 
@@ -790,15 +765,15 @@  SEC("tc")
 int xfrm_get_state(struct __sk_buff *skb)
 {
 	struct bpf_xfrm_state x;
-	char fmt[] = "reqid %d spi 0x%x remote ip 0x%x\n";
 	int ret;
 
 	ret = bpf_skb_get_xfrm_state(skb, 0, &x, sizeof(x), 0);
 	if (ret < 0)
 		return TC_ACT_OK;
 
-	bpf_trace_printk(fmt, sizeof(fmt), x.reqid, bpf_ntohl(x.spi),
-			 bpf_ntohl(x.remote_ipv4));
+	bpf_printk("reqid %d spi 0x%x remote ip 0x%x\n",
+		   x.reqid, bpf_ntohl(x.spi),
+		   bpf_ntohl(x.remote_ipv4));
 	return TC_ACT_OK;
 }