[for-next][PATCH 15/21] ftrace/kprobe: Show the maxactive number on kprobe_events

[for-next][PATCH 15/21] ftrace/kprobe: Show the maxactive number on kprobe_events

[Steven Rostedt]

From: Masami Hiramatsu <mhiramat@kernel.org>

Show maxactive parameter on kprobe_events.
This allows user to save the current configuration and
restore it without losing maxactive parameter.

Link: http://lkml.kernel.org/r/4762764a-6df7-bc93-ed60-e336146dce1f@gmail.com
Link: http://lkml.kernel.org/r/158503528846.22706.5549974121212526020.stgit@devnote2

Cc: stable@vger.kernel.org
Fixes: 696ced4fb1d76 ("tracing/kprobes: expose maxactive for kretprobe in kprobe_events")
Reported-by: Taeung Song <treeze.taeung@gmail.com>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
 kernel/trace/trace_kprobe.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c
index 362cca52f5de..d0568af4a0ef 100644
--- a/kernel/trace/trace_kprobe.c
+++ b/kernel/trace/trace_kprobe.c
@@ -1078,6 +1078,8 @@ static int trace_kprobe_show(struct seq_file *m, struct dyn_event *ev)
 	int i;
 
 	seq_putc(m, trace_kprobe_is_return(tk) ? 'r' : 'p');
+	if (trace_kprobe_is_return(tk) && tk->rp.maxactive)
+		seq_printf(m, "%d", tk->rp.maxactive);
 	seq_printf(m, ":%s/%s", trace_probe_group_name(&tk->tp),
 				trace_probe_name(&tk->tp));
 
-- 
2.25.1

Re: [for-next][PATCH 15/21] ftrace/kprobe: Show the maxactive number on kprobe_events

[Sasha Levin]

Hi

[This is an automated email]

This commit has been processed because it contains a "Fixes:" tag
fixing commit: 696ced4fb1d7 ("tracing/kprobes: expose maxactive for kretprobe in kprobe_events").

The bot has tested the following trees: v5.5.13, v5.4.28, v4.19.113, v4.14.174.

v5.5.13: Build OK!
v5.4.28: Build OK!
v4.19.113: Failed to apply! Possible dependencies:
    533059281ee5 ("tracing: probeevent: Introduce new argument fetching code")
    56de76305279 ("tracing: probeevent: Cleanup print argument functions")
    60c2e0cebfd0 ("tracing: probeevent: Add symbol type")
    6212dd29683e ("tracing/kprobes: Use dyn_event framework for kprobe events")
    a1303af5d79e ("tracing: probeevent: Add $argN for accessing function args")
    b55ce203a8f3 ("tracing/probe: Add probe event name and group name accesses APIs")
    f451bc89d835 ("tracing: probeevent: Unify fetch type tables")

v4.14.174: Failed to apply! Possible dependencies:
    0b4c6841fee0 ("bpf: use the same condition in perf event set/free bpf handler")
    43fa87f7deed ("perf/core: Fix another perf,trace,cpuhp lock inversion")
    45408c4f9250 ("tracing: kprobes: Prohibit probing on notrace function")
    4bebdc7a85aa ("bpf: add helper bpf_perf_prog_read_value")
    533059281ee5 ("tracing: probeevent: Introduce new argument fetching code")
    60c2e0cebfd0 ("tracing: probeevent: Add symbol type")
    6212dd29683e ("tracing/kprobes: Use dyn_event framework for kprobe events")
    908432ca84fc ("bpf: add helper bpf_perf_event_read_value for perf event array map")
    97562633bcba ("bpf: perf event change needed for subsequent bpf helpers")
    9802d86585db ("bpf: add a bpf_override_function helper")
    a1303af5d79e ("tracing: probeevent: Add $argN for accessing function args")
    b4da3340eae2 ("tracing/kprobe: bpf: Check error injectable event is on function entry")
    b55ce203a8f3 ("tracing/probe: Add probe event name and group name accesses APIs")
    d899926f552b ("selftest/ftrace: Move kprobe selftest function to separate compile unit")
    dd0bb688eaa2 ("bpf: add a bpf_override_function helper")
    de8f3a83b0a0 ("bpf: add meta pointer for direct access")
    e12f03d7031a ("perf/core: Implement the 'perf_kprobe' PMU")
    f3edacbd697f ("bpf: Revert bpf_overrid_function() helper changes.")
    f451bc89d835 ("tracing: probeevent: Unify fetch type tables")


NOTE: The patch will not be queued to stable trees until it is upstream.

How should we proceed with this patch?

-- 
Thanks
Sasha