[PATCH] tracing/eprobe: Iterate trace_eprobe directly

From: Chuang Wang
Date: Thu Aug 10 2023 - 04:25:44 EST


Refer to the description in [1], we can skip "container_of()" following
"list_for_each_entry()" by using "list_for_each_entry()" with
"struct trace_eprobe" and "tp.list".

[1] https://lore.kernel.org/all/CAHk-=wjakjw6-rDzDDBsuMoDCqd+9ogifR_EE1F0K-jYek1CdA@xxxxxxxxxxxxxx/

Fixes: 7491e2c44278 ("tracing: Add a probe that attaches to trace events")
Signed-off-by: Chuang Wang <nashuiliang@xxxxxxxxx>
---
kernel/trace/trace_eprobe.c | 13 +++++--------
1 file changed, 5 insertions(+), 8 deletions(-)

diff --git a/kernel/trace/trace_eprobe.c b/kernel/trace/trace_eprobe.c
index a0a704ba27db..d68d660dff7c 100644
--- a/kernel/trace/trace_eprobe.c
+++ b/kernel/trace/trace_eprobe.c
@@ -640,7 +640,7 @@ static int disable_eprobe(struct trace_eprobe *ep,
static int enable_trace_eprobe(struct trace_event_call *call,
struct trace_event_file *file)
{
- struct trace_probe *pos, *tp;
+ struct trace_probe *tp;
struct trace_eprobe *ep;
bool enabled;
int ret = 0;
@@ -662,8 +662,7 @@ static int enable_trace_eprobe(struct trace_event_call *call,
if (enabled)
return 0;

- list_for_each_entry(pos, trace_probe_probe_list(tp), list) {
- ep = container_of(pos, struct trace_eprobe, tp);
+ list_for_each_entry(ep, trace_probe_probe_list(tp), tp.list) {
ret = enable_eprobe(ep, file);
if (ret)
break;
@@ -680,8 +679,7 @@ static int enable_trace_eprobe(struct trace_event_call *call,
*/
WARN_ON_ONCE(ret != -ENOMEM);

- list_for_each_entry(pos, trace_probe_probe_list(tp), list) {
- ep = container_of(pos, struct trace_eprobe, tp);
+ list_for_each_entry(ep, trace_probe_probe_list(tp), tp.list) {
disable_eprobe(ep, file->tr);
if (!--cnt)
break;
@@ -699,7 +697,7 @@ static int enable_trace_eprobe(struct trace_event_call *call,
static int disable_trace_eprobe(struct trace_event_call *call,
struct trace_event_file *file)
{
- struct trace_probe *pos, *tp;
+ struct trace_probe *tp;
struct trace_eprobe *ep;

tp = trace_probe_primary_from_call(call);
@@ -716,8 +714,7 @@ static int disable_trace_eprobe(struct trace_event_call *call,
trace_probe_clear_flag(tp, TP_FLAG_PROFILE);

if (!trace_probe_is_enabled(tp)) {
- list_for_each_entry(pos, trace_probe_probe_list(tp), list) {
- ep = container_of(pos, struct trace_eprobe, tp);
+ list_for_each_entry(ep, trace_probe_probe_list(tp), tp.list) {
disable_eprobe(ep, file->tr);
}
}
--
2.39.2