nettrace: print conguestion state for sock mode

Signed-off-by: Menglong Dong <imagedong@tencent.com>

Author: menglongdong

shared/bpf/skb_macro.h

@@ -46,6 +46,9 @@
 #endif
 
 #ifdef COMPAT_MODE
+#define bpf_core_helper_exist(name)				\
+	bpf_core_enum_value_exists(enum bpf_func_id, BPF_FUNC_##name)
+
 #undef bpf_core_type_exists
 #define bpf_core_type_exists(type) false
 
@@ -54,6 +57,11 @@
 
 #undef bpf_core_enum_value_exists
 #define bpf_core_enum_value_exists(value) false
+
+#undef bpf_core_field_offset
+#define bpf_core_field_offset(type, field) offsetof(type, field)
+#else
+#define bpf_core_helper_exist(name) false
 #endif
 
 #endif

shared/bpf/skb_parse.h

@@ -10,17 +10,12 @@
 #undef bpf_core_type_exists
 #undef bpf_core_field_exists
 #undef bpf_core_enum_value_exists
+#undef bpf_core_field_offset
 #include <bpf/bpf_core_read.h>
 
 #include "skb_macro.h"
 #include "skb_shared.h"
 
-#ifndef COMPAT_MODE
-#define bpf_core_helper_exist(name)				\
-	bpf_core_enum_value_exists(enum bpf_func_id, BPF_FUNC_##name)
-#else
-#define bpf_core_helper_exist(name) false
-#endif
 
 typedef struct {
 	pkt_args_t pkt;
@@ -416,6 +411,12 @@ static try_inline int __probe_parse_sk(parse_ctx_t *ctx)
 	ske->state = _C(skc, skc_state);
 
 	icsk = (void *)sk;
+	bpf_probe_read_kernel(&ske->ca_state, sizeof(u8),
+		(u8 *)icsk +
+		bpf_core_field_offset(struct inet_connection_sock,
+			icsk_retransmits) -
+		1);
+
 	if (bpf_core_helper_exist(jiffies64))
 		ske->timer_out = _C(icsk, icsk_timeout) - (unsigned long)bpf_jiffies64();
 

shared/bpf/skb_shared.h

@@ -118,6 +118,7 @@ typedef struct {
 	u8 proto_l4;
 	u8 timer_pending;
 	u8 state;
+	u8 ca_state;
 } sock_t;
 
 #define TCP_FLAGS_ACK	(1 << 4)

shared/pkt_utils.c

@@ -173,6 +173,21 @@ static const char *state_name[] = {
 	[TCP_LISTEN] = "LISTEN",
 	[TCP_CLOSING] = "CLOSING",
 };
+static const char *ca_name[] = {
+	[TCP_CA_Open] = "CA_Open",
+	[TCP_CA_Disorder] = "CA_Disorder",
+	[TCP_CA_CWR] = "CA_CWR",
+	[TCP_CA_Recovery] = "CA_Recovery",
+	[TCP_CA_Loss] = "CA_Loss",
+};
+
+typedef struct {
+	u8	icsk_ca_state:5,
+		icsk_ca_initialized:1,
+		icsk_ca_setsockopt:1,
+		icsk_ca_dst_locked:1;
+
+} tcp_ca_data_t;
 
 int ts_print_sock(char *buf, sock_t *ske, char *minfo, bool date_format)
 {
@@ -236,10 +251,13 @@ int ts_print_sock(char *buf, sock_t *ske, char *minfo, bool date_format)
 	}
 
 	switch (l4) {
-	case IPPROTO_TCP:
-		BUF_FMT(" %s info:(%u %u)", state_name[ske->state],
+	case IPPROTO_TCP: {
+		tcp_ca_data_t *ca_state = (void *)&ske->ca_state;
+		BUF_FMT(" %s %s info:(%u %u)", state_name[ske->state],
+			ca_name[ca_state->icsk_ca_state],
 			ske->l4.tcp.packets_out,
 			ske->l4.tcp.retrans_out);
+	}
 	case IPPROTO_UDP:
 		hz = kernel_hz();
 		hz = hz > 0 ? hz : 1;