diff mbox series

[v2,bpf,2/5] bpf: remove unnecessary rcu_read_{lock,unlock}() in multi-uprobe attach logic

Message ID 20240521163401.3005045-3-andrii@kernel.org (mailing list archive)
State Accepted
Commit 4a8f635a60540888dab3804992e86410360339c8
Delegated to: BPF
Headers show
Series Fix BPF multi-uprobe PID filtering logic | expand

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Commit Message

Andrii Nakryiko May 21, 2024, 4:33 p.m. UTC 
get_pid_task() internally already calls rcu_read_lock() and
rcu_read_unlock(), so there is no point to do this one extra time.

This is a drive-by improvement and has no correctness implications.

Acked-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
---
 kernel/trace/bpf_trace.c | 2 --
 1 file changed, 2 deletions(-)
diff mbox series

Patch

diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c
index 1baaeb9ca205..6249dac61701 100644
--- a/kernel/trace/bpf_trace.c
+++ b/kernel/trace/bpf_trace.c
@@ -3423,9 +3423,7 @@  int bpf_uprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *pr
 	}
 
 	if (pid) {
-		rcu_read_lock();
 		task = get_pid_task(find_vpid(pid), PIDTYPE_TGID);
-		rcu_read_unlock();
 		if (!task) {
 			err = -ESRCH;
 			goto error_path_put;