libbpf: add support for tracing session

Add BPF_TRACE_SESSION to libbpf and bpftool.

Signed-off-by: Menglong Dong <[email protected]>

Author: image-dragon

tools/bpf/bpftool/common.c

@@ -1191,6 +1191,7 @@ const char *bpf_attach_type_input_str(enum bpf_attach_type t)
 	case BPF_TRACE_FENTRY:			return "fentry";
 	case BPF_TRACE_FEXIT:			return "fexit";
 	case BPF_MODIFY_RETURN:			return "mod_ret";
+	case BPF_TRACE_SESSION:			return "fsession";
 	case BPF_SK_REUSEPORT_SELECT:		return "sk_skb_reuseport_select";
 	case BPF_SK_REUSEPORT_SELECT_OR_MIGRATE:	return "sk_skb_reuseport_select_or_migrate";
 	default:	return libbpf_bpf_attach_type_str(t);

tools/lib/bpf/bpf.c

@@ -794,6 +794,7 @@ int bpf_link_create(int prog_fd, int target_fd,
 	case BPF_TRACE_FENTRY:
 	case BPF_TRACE_FEXIT:
 	case BPF_MODIFY_RETURN:
+	case BPF_TRACE_SESSION:
 	case BPF_LSM_MAC:
 		attr.link_create.tracing.cookie = OPTS_GET(opts, tracing.cookie, 0);
 		if (!OPTS_ZEROED(opts, tracing))
@@ -917,6 +918,7 @@ int bpf_link_create(int prog_fd, int target_fd,
 	case BPF_TRACE_FENTRY:
 	case BPF_TRACE_FEXIT:
 	case BPF_MODIFY_RETURN:
+	case BPF_TRACE_SESSION:
 		return bpf_raw_tracepoint_open(NULL, prog_fd);
 	default:
 		return libbpf_err(err);

tools/lib/bpf/libbpf.c

@@ -115,6 +115,7 @@ static const char * const attach_type_name[] = {
 	[BPF_TRACE_FENTRY]		= "trace_fentry",
 	[BPF_TRACE_FEXIT]		= "trace_fexit",
 	[BPF_MODIFY_RETURN]		= "modify_return",
+	[BPF_TRACE_SESSION]		= "trace_session",
 	[BPF_LSM_MAC]			= "lsm_mac",
 	[BPF_LSM_CGROUP]		= "lsm_cgroup",
 	[BPF_SK_LOOKUP]			= "sk_lookup",
@@ -9607,6 +9608,8 @@ static const struct bpf_sec_def section_defs[] = {
 	SEC_DEF("fentry.s+",		TRACING, BPF_TRACE_FENTRY, SEC_ATTACH_BTF | SEC_SLEEPABLE, attach_trace),
 	SEC_DEF("fmod_ret.s+",		TRACING, BPF_MODIFY_RETURN, SEC_ATTACH_BTF | SEC_SLEEPABLE, attach_trace),
 	SEC_DEF("fexit.s+",		TRACING, BPF_TRACE_FEXIT, SEC_ATTACH_BTF | SEC_SLEEPABLE, attach_trace),
+	SEC_DEF("fsession+",		TRACING, BPF_TRACE_SESSION, SEC_ATTACH_BTF, attach_trace),
+	SEC_DEF("fsession.s+",		TRACING, BPF_TRACE_SESSION, SEC_ATTACH_BTF | SEC_SLEEPABLE, attach_trace),
 	SEC_DEF("freplace+",		EXT, 0, SEC_ATTACH_BTF, attach_trace),
 	SEC_DEF("lsm+",			LSM, BPF_LSM_MAC, SEC_ATTACH_BTF, attach_lsm),
 	SEC_DEF("lsm.s+",		LSM, BPF_LSM_MAC, SEC_ATTACH_BTF | SEC_SLEEPABLE, attach_lsm),