fix: fix pprof by register handlers explicitly

see https://pkg.go.dev/net/http/pprof
> By default, all the profiles listed in runtime/pprof.Profile are
available (via Handler), in addition to the Cmdline, Profile, Symbol,
and Trace profiles defined in this package. If you are not using
DefaultServeMux, you will have to register handlers with the mux you are
using.

Signed-off-by: j4ckstraw <j4ckstraw@foxmail.com>

pkg/exporters/k8sexporter/k8s_exporter.go

@@ -20,7 +20,7 @@ import (
 	"context"
 	"net"
 	"net/http"
-	_ "net/http/pprof"
+	"net/http/pprof"
 	"strconv"
 
 	"k8s.io/klog/v2"
@@ -95,6 +95,13 @@ func (ke *k8sExporter) startHTTPReporting(npdo *options.NodeProblemDetectorOptio
 		util.ReturnHTTPJson(w, ke.conditionManager.GetConditions())
 	})
 
+	// register pprof
+	mux.HandleFunc("/debug/pprof/", pprof.Index)
+	mux.HandleFunc("/debug/pprof/cmdline", pprof.Cmdline)
+	mux.HandleFunc("/debug/pprof/profile", pprof.Profile)
+	mux.HandleFunc("/debug/pprof/symbol", pprof.Symbol)
+	mux.HandleFunc("/debug/pprof/trace", pprof.Trace)
+
 	addr := net.JoinHostPort(npdo.ServerAddress, strconv.Itoa(npdo.ServerPort))
 	go func() {
 		err := http.ListenAndServe(addr, mux)