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| author | Steven Rostedt (VMware) <rostedt@goodmis.org> | 2021-08-17 06:42:57 +0300 |
|---|---|---|
| committer | Steven Rostedt (VMware) <rostedt@goodmis.org> | 2021-08-19 01:13:47 +0300 |
| commit | 1d18538e6a09265003a0a94ca779d7a6127cb76c (patch) | |
| tree | 79c71bb9a4c4ed5a3848bdbb155b6b1dfe8a08a0 /kernel/trace/trace_kprobe.c | |
| parent | 8b0e6c744fef6462382041b30878c91f15069fc6 (diff) | |
| download | linux-1d18538e6a09265003a0a94ca779d7a6127cb76c.tar.xz | |
tracing: Have dynamic events have a ref counter
As dynamic events are not created by modules, if something is attached to
one, calling "try_module_get()" on its "mod" field, is not going to keep
the dynamic event from going away.
Since dynamic events do not need the "mod" pointer of the event structure,
make a union out of it in order to save memory (there's one structure for
each of the thousand+ events in the kernel), and have any event with the
DYNAMIC flag set to use a ref counter instead.
Link: https://lore.kernel.org/linux-trace-devel/20210813004448.51c7de69ce432d338f4d226b@kernel.org/
Link: https://lkml.kernel.org/r/20210817035027.174869074@goodmis.org
Suggested-by: Masami Hiramatsu <mhiramat@kernel.org>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Diffstat (limited to 'kernel/trace/trace_kprobe.c')
| -rw-r--r-- | kernel/trace/trace_kprobe.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c index bfef43bfce37..82c3b86013b2 100644 --- a/kernel/trace/trace_kprobe.c +++ b/kernel/trace/trace_kprobe.c @@ -543,6 +543,10 @@ static int unregister_trace_kprobe(struct trace_kprobe *tk) if (trace_probe_is_enabled(&tk->tp)) return -EBUSY; + /* If there's a reference to the dynamic event */ + if (trace_event_dyn_busy(trace_probe_event_call(&tk->tp))) + return -EBUSY; + /* Will fail if probe is being used by ftrace or perf */ if (unregister_kprobe_event(tk)) return -EBUSY; |