internal/debug: enhance pyroscope profiler with tag support

- Updated StartPyroscopeProfiler to accept a map of tags for profiling data.
- Introduced a new command-line flag for specifying comma-separated key=value tags.
- Modified Setup function to parse and pass tags to the profiler, improving profiling data granularity.

internal/debug/api.go

@@ -148,7 +148,10 @@ func (l *pyroscopeLogger) Errorf(format string, v ...interface{}) {
 }
 
 // StartPyroscopeProfiler starts the Pyroscope profiler for later use
-func (h *HandlerT) StartPyroscopeProfiler(server string) error {
+func (h *HandlerT) StartPyroscopeProfiler(
+	server string,
+	tags map[string]string,
+) error {
 	h.mu.Lock()
 	defer h.mu.Unlock()
 	if h.profiler != nil {
@@ -160,7 +163,7 @@ func (h *HandlerT) StartPyroscopeProfiler(server string) error {
 			ApplicationName: "geth",
 			ServerAddress:   server,
 			Logger:          &pyroscopeLogger{Logger: log.Root().With("module", "pyroscope")},
-			// Tags: nil,
+			Tags:            tags,
 			ProfileTypes: []pyroscope.ProfileType{
 				// Enabling all profile types
 				pyroscope.ProfileCPU,

internal/debug/flags.go

@@ -26,6 +26,7 @@ import (
 	"os"
 	"path/filepath"
 	"runtime"
+	"strings"
 
 	"github.com/ethereum/go-ethereum/internal/flags"
 	"github.com/ethereum/go-ethereum/log"
@@ -152,6 +153,12 @@ var (
 		Value:    "http://localhost:4040",
 		Category: flags.LoggingCategory,
 	}
+	pyroscopeTagsFlag = &cli.StringFlag{
+		Name:     "pyroscope.tags",
+		Usage:    "Comma separated list of key=value tags to add to profiling data",
+		Value:    "",
+		Category: flags.LoggingCategory,
+	}
 )
 
 // Flags holds all command-line flags required for debugging.
@@ -317,7 +324,17 @@ func Setup(ctx *cli.Context) error {
 	if ctx.Bool(pyroscopeFlag.Name) {
 		pyroscopeServer := ctx.String(pyroscopeServerFlag.Name)
 
-		Handler.StartPyroscopeProfiler(pyroscopeServer)
+		rawTags := ctx.String(pyroscopeTagsFlag.Name)
+		tags := make(map[string]string)
+		for _, tag := range strings.Split(rawTags, ",") {
+			kv := strings.Split(tag, "=")
+			// Ignore invalid tags
+			if len(kv) == 2 {
+				tags[kv[0]] = kv[1]
+			}
+		}
+
+		Handler.StartPyroscopeProfiler(pyroscopeServer, tags)
 	}
 
 	if len(logFile) > 0 || rotation {