[PATCH 2/3] perf/probe: Show return probe correctly with --bootconfig

From: Masami Hiramatsu
Date: Fri Jun 18 2021 - 12:11:07 EST


Since the bootconfig has to use "%return" suffix for the return
probes, perf probe also needs to add that suffix if the user
defines the return probe. E.g.

$ perf probe -k vmlinux --bootconfig -D vfs_read%return
ftrace.event.kprobes.vfs_read__return.probe = 'vfs_read+0%return'

Signed-off-by: Masami Hiramatsu <mhiramat@xxxxxxxxxx>
---
tools/perf/util/probe-event.c | 12 +++++++-----
1 file changed, 7 insertions(+), 5 deletions(-)

diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c
index 8e30bf97cf0f..99624e39314b 100644
--- a/tools/perf/util/probe-event.c
+++ b/tools/perf/util/probe-event.c
@@ -2166,15 +2166,17 @@ synthesize_uprobe_trace_def(struct probe_trace_point *tp, struct strbuf *buf)
}

static int
-synthesize_kprobe_trace_def(struct probe_trace_point *tp, struct strbuf *buf)
+synthesize_kprobe_trace_def(struct probe_trace_point *tp, struct strbuf *buf,
+ bool show_return)
{
if (!strncmp(tp->symbol, "0x", 2)) {
/* Absolute address. See try_to_find_absolute_address() */
return strbuf_addf(buf, "%s%s0x%lx", tp->module ?: "",
tp->module ? ":" : "", tp->address);
} else {
- return strbuf_addf(buf, "%s%s%s+%lu", tp->module ?: "",
- tp->module ? ":" : "", tp->symbol, tp->offset);
+ return strbuf_addf(buf, "%s%s%s+%lu%s", tp->module ?: "",
+ tp->module ? ":" : "", tp->symbol, tp->offset,
+ show_return && tp->retprobe ? "%return" : "");
}
}

@@ -2195,7 +2197,7 @@ char *synthesize_probe_trace_command(struct probe_trace_event *tev)
if (tev->uprobes)
err = synthesize_uprobe_trace_def(tp, &buf);
else
- err = synthesize_kprobe_trace_def(tp, &buf);
+ err = synthesize_kprobe_trace_def(tp, &buf, false);

if (err >= 0)
err = synthesize_probe_trace_args(tev, &buf);
@@ -3574,7 +3576,7 @@ static int show_bootconfig_event(struct probe_trace_event *tev)
if (strbuf_init(&buf, 32) < 0)
return -ENOMEM;

- err = synthesize_kprobe_trace_def(tp, &buf);
+ err = synthesize_kprobe_trace_def(tp, &buf, true);
if (err >= 0)
err = synthesize_probe_trace_args(tev, &buf);
if (err >= 0)