Enable auto/sdk in otel global

CHANGELOG.md

@@ -18,6 +18,7 @@ OpenTelemetry Go Automatic Instrumentation adheres to [Semantic Versioning](http
 - Support `google.golang.org/grpc` `1.68.2`. ([#1462](https://github.com/open-telemetry/opentelemetry-go-instrumentation/pull/1462))
 - Support `google.golang.org/grpc` `1.69.2`. ([#1467](https://github.com/open-telemetry/opentelemetry-go-instrumentation/pull/1467))
 - Support `golang.org/x/net` `0.33.0`. ([#1471](https://github.com/open-telemetry/opentelemetry-go-instrumentation/pull/1471))
+- Support the full tracing API with the `otelglobal` probe. ([#1405](https://github.com/open-telemetry/opentelemetry-go-instrumentation/pull/1405))
 
 ## [v0.19.0-alpha] - 2024-12-05
 

internal/pkg/instrumentation/bpf/database/sql/probe.go

@@ -53,7 +53,7 @@ func New(logger *slog.Logger, version string) probe.Probe {
 					Val: shouldIncludeDBStatement(),
 				},
 			},
-			Uprobes: []probe.Uprobe{
+			Uprobes: []*probe.Uprobe{
 				{
 					Sym:         "database/sql.(*DB).queryDC",
 					EntryProbe:  "uprobe_queryDC",

internal/pkg/instrumentation/bpf/github.com/segmentio/kafka-go/consumer/probe.go

@@ -69,7 +69,7 @@ func New(logger *slog.Logger, version string) probe.Probe {
 					Val: structfield.NewID("github.com/segmentio/kafka-go", "github.com/segmentio/kafka-go", "ReaderConfig", "GroupID"),
 				},
 			},
-			Uprobes: []probe.Uprobe{
+			Uprobes: []*probe.Uprobe{
 				{
 					Sym:         "github.com/segmentio/kafka-go.(*Reader).FetchMessage",
 					EntryProbe:  "uprobe_FetchMessage",

internal/pkg/instrumentation/bpf/github.com/segmentio/kafka-go/producer/probe.go

@@ -57,7 +57,7 @@ func New(logger *slog.Logger, version string) probe.Probe {
 					Val: structfield.NewID("github.com/segmentio/kafka-go", "github.com/segmentio/kafka-go", "Message", "Time"),
 				},
 			},
-			Uprobes: []probe.Uprobe{
+			Uprobes: []*probe.Uprobe{
 				{
 					Sym:         "github.com/segmentio/kafka-go.(*Writer).WriteMessages",
 					EntryProbe:  "uprobe_WriteMessages",

internal/pkg/instrumentation/bpf/go.opentelemetry.io/auto/sdk/probe.go

@@ -60,7 +60,7 @@ func New(logger *slog.Logger) probe.Probe {
 					),
 				},
 			},
-			Uprobes: []probe.Uprobe{
+			Uprobes: []*probe.Uprobe{
 				{
 					Sym:        "go.opentelemetry.io/auto/sdk.(*tracer).start",
 					EntryProbe: "uprobe_Tracer_start",
@@ -86,25 +86,25 @@ type converter struct {
 	logger *slog.Logger
 }
 
-func (c *converter) decodeEvent(record perf.Record) (event, error) {
+func (c *converter) decodeEvent(record perf.Record) (*event, error) {
 	reader := bytes.NewReader(record.RawSample)
 
 	var e event
 	err := binary.Read(reader, binary.LittleEndian, &e.Size)
 	if err != nil {
 		c.logger.Error("failed to decode size", "error", err)
-		return event{}, err
+		return nil, err
 	}
 	c.logger.Debug("decoded size", "size", e.Size)
 
 	e.SpanData = make([]byte, e.Size)
 	_, err = reader.Read(e.SpanData)
 	if err != nil {
 		c.logger.Error("failed to read span data", "error", err)
-		return event{}, err
+		return nil, err
 	}
 	c.logger.Debug("decoded span data", "size", e.Size)
-	return e, nil
+	return &e, nil
 }
 
 func (c *converter) processFn(e *event) ptrace.ScopeSpans {

internal/pkg/instrumentation/bpf/go.opentelemetry.io/otel/traceglobal/bpf/probe.bpf.c

@@ -23,6 +23,9 @@ char __license[] SEC("license") = "Dual MIT/GPL";
 #define MAX_BUCKETS 8
 #define MAX_TRACERS 64
 
+// Records state of our write to auto-instrumentation flag.
+bool wrote_flag = false;
+
 struct span_description_t {
     char buf[MAX_STATUS_DESCRIPTION_LEN];
 };
@@ -42,7 +45,12 @@ typedef struct tracer_id {
     char schema_url[MAX_TRACER_SCHEMA_URL_LEN];
 } tracer_id_t;
 
+struct control_t {
+    u32 kind; // Required to be 1.
+};
+
 struct otel_span_t {
+    u32 kind; // Required to be 0.
     BASE_SPAN_PROPERTIES
     struct span_name_t span_name;
     otel_status_t status;
@@ -388,6 +396,36 @@ static __always_inline long fill_tracer_id(tracer_id_t *tracer_id, go_tracer_ptr
     return 0;
 }
 
+// This instrumentation attaches uprobe to the following function:
+// func (t *tracer) newSpan(ctx context.Context, autoSpan *bool, name string, opts []trace.SpanStartOption) (context.Context, trace.Span) {
+// https://github.com/open-telemetry/opentelemetry-go/blob/ac386f383cdfc14f546b4e55e8726a0a45e8a409/internal/global/trace.go#L161
+SEC("uprobe/newSpan")
+int uprobe_newStart(struct pt_regs *ctx) {
+    if (wrote_flag) {
+        // Already wrote flag value.
+        return 0;
+    }
+
+    void *flag_ptr = get_argument(ctx, 4);
+    if (flag_ptr == NULL) {
+        bpf_printk("invalid flag_ptr: NULL");
+        return -1;
+    }
+
+    bool true_value = true;
+    long res = bpf_probe_write_user(flag_ptr, &true_value, sizeof(bool));
+    if (res != 0) {
+        bpf_printk("failed to write bool flag value: %ld", res);
+        return -2;
+    }
+
+    wrote_flag = true;
+
+    // Signal this uprobe should be unloaded.
+    struct control_t ctrl = {1};
+    return bpf_perf_event_output(ctx, &events, BPF_F_CURRENT_CPU, (void *)(&ctrl), sizeof(struct control_t));
+}
+
 // This instrumentation attaches uprobe to the following function:
 // func (t *tracer) Start(ctx context.Context, name string, opts ...trace.SpanStartOption) (context.Context, trace.Span)
 // https://github.com/open-telemetry/opentelemetry-go/blob/98b32a6c3a87fbee5d34c063b9096f416b250897/internal/global/trace.go#L149