From 6d0ca913080494e381c5092cf10ac7fa89212868 Mon Sep 17 00:00:00 2001
From: Leon Hwang <hffilwlqm@gmail.com>
Date: Fri, 6 Dec 2024 21:26:16 +0800
Subject: [PATCH] bpflbr: Reduce output when not verbose

Adjust some behaviours aboud verbose:

1. Skip 14 LBR entries when not verbose.
2. Skip 3 stack entries when verbose.
3. Do not show addrs of LBR entries when not verbose.
4. Show addrs of stack entries when verbose.

Signed-off-by: Leon Hwang <hffilwlqm@gmail.com>
---
 internal/bpflbr/lbr.go       | 23 +++++++++++++++--------
 internal/bpflbr/lbr_stack.go | 14 +++++++++-----
 2 files changed, 24 insertions(+), 13 deletions(-)

diff --git a/internal/bpflbr/lbr.go b/internal/bpflbr/lbr.go
index 029bedb..1f2f2c6 100644
--- a/internal/bpflbr/lbr.go
+++ b/internal/bpflbr/lbr.go
@@ -166,6 +166,12 @@ func getLbrStack(event *Event, progs *bpfProgs, addr2line *Addr2Line, ksyms *Kal
 	nrEntries := event.NrBytes / int64(8*3)
 	entries := event.Entries[:nrEntries]
 	if !verbose {
+		// Skip the first 14 entries as they are entries for fexit_fn
+		// and bpf_get_branch_snapshot helper.
+		const nrSkip = 14
+
+		entries = entries[nrSkip:]
+
 		if isProg {
 			for i := range entries {
 				if progInfo.contains(entries[i].From) || progInfo.contains(entries[i].To) {
@@ -180,12 +186,6 @@ func getLbrStack(event *Event, progs *bpfProgs, addr2line *Addr2Line, ksyms *Kal
 					break
 				}
 			}
-		} else {
-			// Skip the first 14 entries as they are entries for fexit_fn
-			// and bpf_get_branch_snapshot helper.
-			const nrSkip = 14
-
-			entries = entries[nrSkip:]
 		}
 
 		if len(entries) == 0 {
@@ -222,13 +222,20 @@ func getFuncStack(event *Event, progs *bpfProgs, addr2line *Addr2Line, ksym *Kal
 	}
 	_ = funcStacks.Delete(id)
 
-	ips := data.IPs[3:] // Skip the first 3 entries as they are entries for fentry/fexit and its trampoline.
+	ips := data.IPs[:]
+	if !verbose {
+		ips = ips[3:] // Skip the first 3 entries as they are entries for fentry/fexit and its trampoline.
+	}
 	for _, ip := range ips {
 		if ip != 0 {
 			li := getLineInfo(uintptr(ip), progs, addr2line, ksym)
 
 			var sb strings.Builder
-			fmt.Fprintf(&sb, "  %-50s", fmt.Sprintf("%s+%#x", li.funcName, li.offset))
+			fmt.Fprint(&sb, "  ")
+			if verbose {
+				fmt.Fprintf(&sb, "0x%x:", ip)
+			}
+			fmt.Fprintf(&sb, "%-50s", fmt.Sprintf("%s+%#x", li.funcName, li.offset))
 			if li.fileName != "" {
 				fmt.Fprintf(&sb, "\t; %s:%d", li.fileName, li.fileLine)
 			}
diff --git a/internal/bpflbr/lbr_stack.go b/internal/bpflbr/lbr_stack.go
index 80712c8..aaa5145 100644
--- a/internal/bpflbr/lbr_stack.go
+++ b/internal/bpflbr/lbr_stack.go
@@ -15,15 +15,19 @@ type branchEndpoint struct {
 	offset       uintptr
 	endpointName string // ${funcName}+${offset}
 
-	fileName string
-	fileLine uint32
-	lineInfo string // (${fileName}:${fileLine})
-	isProg   bool
+	fileName    string
+	fileLine    uint32
+	lineInfo    string // (${fileName}:${fileLine})
+	isProg      bool
 	fromVmlinux bool
 }
 
 func (b *branchEndpoint) updateInfo() {
-	b.endpointName = fmt.Sprintf("%#x:%s+%#x", b.addr, b.funcName, b.offset)
+	if verbose {
+		b.endpointName = fmt.Sprintf("%#x:%s+%#x", b.addr, b.funcName, b.offset)
+	} else {
+		b.endpointName = fmt.Sprintf("%s+%#x", b.funcName, b.offset)
+	}
 	if b.fileName != "" {
 		b.lineInfo = fmt.Sprintf("(%s:%d)", b.fileName, b.fileLine)
 	}