The patch below does not apply to the 4.19-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From dfea08a2116fe327f79d8f4d4b2cf6e0c88be11f Mon Sep 17 00:00:00 2001 From: Xiangyang Zhang xyz.sun.ok@gmail.com Date: Fri, 7 Jan 2022 23:02:42 +0800 Subject: [PATCH] tracing/kprobes: 'nmissed' not showed correctly for kretprobe
The 'nmissed' column of the 'kprobe_profile' file for kretprobe is not showed correctly, kretprobe can be skipped by two reasons, shortage of kretprobe_instance which is counted by tk->rp.nmissed, and kprobe itself is missed by some reason, so to show the sum.
Link: https://lkml.kernel.org/r/20220107150242.5019-1-xyz.sun.ok@gmail.com
Cc: stable@vger.kernel.org Fixes: 4a846b443b4e ("tracing/kprobes: Cleanup kprobe tracer code") Acked-by: Masami Hiramatsu mhiramat@kernel.org Signed-off-by: Xiangyang Zhang xyz.sun.ok@gmail.com Signed-off-by: Steven Rostedt rostedt@goodmis.org
diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c index f8c26ee72de3..3d85323278ed 100644 --- a/kernel/trace/trace_kprobe.c +++ b/kernel/trace/trace_kprobe.c @@ -1170,15 +1170,18 @@ static int probes_profile_seq_show(struct seq_file *m, void *v) { struct dyn_event *ev = v; struct trace_kprobe *tk; + unsigned long nmissed;
if (!is_trace_kprobe(ev)) return 0;
tk = to_trace_kprobe(ev); + nmissed = trace_kprobe_is_return(tk) ? + tk->rp.kp.nmissed + tk->rp.nmissed : tk->rp.kp.nmissed; seq_printf(m, " %-44s %15lu %15lu\n", trace_probe_name(&tk->tp), trace_kprobe_nhit(tk), - tk->rp.kp.nmissed); + nmissed);
return 0; }