Support gRPC status for versions >=1.40

open-telemetry · Oct 31, 2024 · 424a09f · 424a09f
1 parent 77e8de9
commit 424a09f
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Showing 4 changed files with 38 additions and 0 deletions.
diff --git a/internal/pkg/instrumentation/bpf/google.golang.org/grpc/client/bpf/probe.bpf.c b/internal/pkg/instrumentation/bpf/google.golang.org/grpc/client/bpf/probe.bpf.c
@@ -53,6 +53,8 @@ volatile const u64 error_status_pos;
 volatile const u64 status_s_pos;
 volatile const u64 status_code_pos;
 
+volatile const bool write_status_supported;
+
 // This instrumentation attaches uprobe to the following function:
 // func (cc *ClientConn) Invoke(ctx context.Context, method string, args, reply interface{}, opts ...CallOption) error
 SEC("uprobe/ClientConn_Invoke")
@@ -122,6 +124,9 @@ int uprobe_ClientConn_Invoke_Returns(struct pt_regs *ctx) {
         return 0;
     }
 
+    if(!write_status_supported) {
+        goto done;
+    }
     // Getting the returned response (error)
     // The status code is embedded 3 layers deep:
     // Invoke() error

diff --git a/internal/pkg/instrumentation/bpf/google.golang.org/grpc/client/probe.go b/internal/pkg/instrumentation/bpf/google.golang.org/grpc/client/probe.go
@@ -10,15 +10,18 @@ import (
 	"strings"
 
 	"github.com/cilium/ebpf"
+	"github.com/hashicorp/go-version"
 	"go.opentelemetry.io/otel/attribute"
 	"go.opentelemetry.io/otel/codes"
 	semconv "go.opentelemetry.io/otel/semconv/v1.26.0"
 	"go.opentelemetry.io/otel/trace"
 	"golang.org/x/sys/unix"
 
+	"go.opentelemetry.io/auto/internal/pkg/inject"
 	"go.opentelemetry.io/auto/internal/pkg/instrumentation/context"
 	"go.opentelemetry.io/auto/internal/pkg/instrumentation/probe"
 	"go.opentelemetry.io/auto/internal/pkg/instrumentation/utils"
+	"go.opentelemetry.io/auto/internal/pkg/process"
 	"go.opentelemetry.io/auto/internal/pkg/structfield"
 )
 
@@ -29,6 +32,17 @@ const (
 	pkg = "google.golang.org/grpc"
 )
 
+type writeStatusConst struct{}
+
+func (w writeStatusConst) InjectOption(td *process.TargetDetails) (inject.Option, error) {
+	writeStatusVersion := version.Must(version.NewVersion("1.40.0"))
+	ver, ok := td.Libraries[pkg]
+	if !ok {
+		return nil, fmt.Errorf("unknown module version: %s", pkg)
+	}
+	return inject.WithKeyValue("write_status_supported", ver.GreaterThanOrEqual(writeStatusVersion)), nil
+}
+
 // New returns a new [probe.Probe].
 func New(logger *slog.Logger) probe.Probe {
 	id := probe.ID{
@@ -41,6 +55,7 @@ func New(logger *slog.Logger) probe.Probe {
 		Consts: []probe.Const{
 			probe.RegistersABIConst{},
 			probe.AllocationConst{},
+			writeStatusConst{},
 			probe.StructFieldConst{
 				Key: "clientconn_target_ptr_pos",
 				Val: structfield.NewID("google.golang.org/grpc", "google.golang.org/grpc", "ClientConn", "target"),

diff --git a/internal/pkg/instrumentation/bpf/google.golang.org/grpc/server/bpf/probe.bpf.c b/internal/pkg/instrumentation/bpf/google.golang.org/grpc/server/bpf/probe.bpf.c
@@ -63,6 +63,8 @@ volatile const bool is_new_frame_pos;
 volatile const u64 status_s_pos;
 volatile const u64 status_code_pos;
 
+volatile const bool write_status_supported;
+
 static __always_inline long dummy_extract_span_context_from_headers(void *stream_id, struct span_context *parent_span_context) {
     return 0;
 }
@@ -175,6 +177,10 @@ int uprobe_http2Server_operateHeader(struct pt_regs *ctx)
 // https://github.com/grpc/grpc-go/blob/bcf9171a20e44ed81a6eb152e3ca9e35b2c02c5d/internal/transport/http2_server.go#L1049
 SEC("uprobe/http2Server_WriteStatus")
 int uprobe_http2Server_WriteStatus(struct pt_regs *ctx) {
+    if(!write_status_supported) {
+        bpf_printk("status probe not supported for this version of gRPC");
+        return 0;
+    }
     struct go_iface go_context = {0};
     get_Go_context(ctx, 2, stream_ctx_pos, true, &go_context);
     void *key = get_consistent_key(ctx, go_context.data);

diff --git a/internal/pkg/instrumentation/bpf/google.golang.org/grpc/server/probe.go b/internal/pkg/instrumentation/bpf/google.golang.org/grpc/server/probe.go
@@ -31,6 +31,17 @@ const (
 	pkg = "google.golang.org/grpc"
 )
 
+type writeStatusConst struct{}
+
+func (w writeStatusConst) InjectOption(td *process.TargetDetails) (inject.Option, error) {
+	writeStatusVersion := version.Must(version.NewVersion("1.40.0"))
+	ver, ok := td.Libraries[pkg]
+	if !ok {
+		return nil, fmt.Errorf("unknown module version: %s", pkg)
+	}
+	return inject.WithKeyValue("write_status_supported", ver.GreaterThanOrEqual(writeStatusVersion)), nil
+}
+
 // New returns a new [probe.Probe].
 func New(logger *slog.Logger) probe.Probe {
 	id := probe.ID{
@@ -43,6 +54,7 @@ func New(logger *slog.Logger) probe.Probe {
 		Consts: []probe.Const{
 			probe.RegistersABIConst{},
 			probe.AllocationConst{},
+			writeStatusConst{},
 			probe.StructFieldConst{
 				Key: "stream_method_ptr_pos",
 				Val: structfield.NewID("google.golang.org/grpc", "google.golang.org/grpc/internal/transport", "Stream", "method"),