Add --output-caller flag

Signed-off-by: gray <[email protected]>

README.md

@@ -66,6 +66,7 @@ Usage: pwru [options] [pcap-filter]
   -h, --help                           display this message and exit
       --kernel-btf string              specify kernel BTF file
       --kmods strings                  list of kernel modules names to attach to
+      --output-caller                  print caller function name
       --output-file string             write traces to file
       --output-json                    output traces in JSON format
       --output-limit-lines uint        exit the program after the number of events has been received/printed

bpf/kprobe_pwru.c

@@ -102,7 +102,8 @@ struct config {
 	u8 output_skb: 1;
 	u8 output_shinfo: 1;
 	u8 output_stack: 1;
-	u8 output_unused: 3;
+	u8 output_caller: 1;
+	u8 output_unused: 2;
 	u8 is_set: 1;
 	u8 track_skb: 1;
 	u8 track_skb_by_stackid: 1;

internal/pwru/config.go

@@ -21,6 +21,7 @@ const (
 	OutputSkbMask
 	OutputShinfoMask
 	OutputStackMask
+	OutputCallerMask
 )
 
 const (
@@ -61,6 +62,9 @@ func GetConfig(flags *Flags) (cfg FilterCfg, err error) {
 	if flags.OutputStack {
 		cfg.OutputFlags |= OutputStackMask
 	}
+	if flags.OutputCaller {
+		cfg.OutputFlags |= OutputCallerMask
+	}
 	if flags.FilterTrackSkb {
 		cfg.FilterFlags |= TrackSkbMask
 	}

internal/pwru/types.go

@@ -43,6 +43,7 @@ type Flags struct {
 	OutputSkb        bool
 	OutputShinfo     bool
 	OutputStack      bool
+	OutputCaller     bool
 	OutputLimitLines uint64
 	OutputFile       string
 	OutputJson       bool
@@ -76,6 +77,7 @@ func (f *Flags) SetFlags() {
 	flag.BoolVar(&f.OutputSkb, "output-skb", false, "print skb")
 	flag.BoolVar(&f.OutputShinfo, "output-skb-shared-info", false, "print skb shared info")
 	flag.BoolVar(&f.OutputStack, "output-stack", false, "print stack")
+	flag.BoolVar(&f.OutputCaller, "output-caller", false, "print caller function name")
 	flag.Uint64Var(&f.OutputLimitLines, "output-limit-lines", 0, "exit the program after the number of events has been received/printed")
 
 	flag.StringVar(&f.OutputFile, "output-file", "", "write traces to file")