Commit 2cba0070 authored by Masami Hiramatsu (Google)'s avatar Masami Hiramatsu (Google)
Browse files

tracing/kprobe: Adopt guard() and scoped_guard() 

Use guard() or scoped_guard() in kprobe events for critical sections
rather than discrete lock/unlock pairs.

Link: https://lore.kernel.org/all/173289888883.73724.6586200652276577583.stgit@devnote2/



Signed-off-by: default avatarMasami Hiramatsu (Google) <mhiramat@kernel.org>
parent 587e8e6d

kernel/trace/trace_kprobe.c

+6 −12
Original line number Diff line number Diff line
@@ -634,7 +634,7 @@ static int register_trace_kprobe(struct trace_kprobe *tk) 
	struct trace_kprobe *old_tk;

	int ret;



	mutex_lock(&event_mutex);

	guard(mutex)(&event_mutex);



	old_tk = find_trace_kprobe(trace_probe_name(&tk->tp),

				   trace_probe_group_name(&tk->tp));
@@ -642,11 +642,9 @@ static int register_trace_kprobe(struct trace_kprobe *tk) 
		if (trace_kprobe_is_return(tk) != trace_kprobe_is_return(old_tk)) {

			trace_probe_log_set_index(0);

			trace_probe_log_err(0, DIFF_PROBE_TYPE);

			ret = -EEXIST;

		} else {

			ret = append_trace_kprobe(tk, old_tk);

			return -EEXIST;

		}

		goto end;

		return append_trace_kprobe(tk, old_tk);

	}



	/* Register new event */
@@ -657,7 +655,7 @@ static int register_trace_kprobe(struct trace_kprobe *tk) 
			trace_probe_log_err(0, EVENT_EXIST);

		} else

			pr_warn("Failed to register probe event(%d)\n", ret);

		goto end;

		return ret;

	}



	/* Register k*probe */
@@ -672,8 +670,6 @@ static int register_trace_kprobe(struct trace_kprobe *tk) 
	else

		dyn_event_add(&tk->devent, trace_probe_event_call(&tk->tp));



end:

	mutex_unlock(&event_mutex);

	return ret;

}
@@ -706,7 +702,7 @@ static int trace_kprobe_module_callback(struct notifier_block *nb, 
		return NOTIFY_DONE;



	/* Update probes on coming module */

	mutex_lock(&event_mutex);

	guard(mutex)(&event_mutex);

	for_each_trace_kprobe(tk, pos) {

		if (trace_kprobe_within_module(tk, mod)) {

			/* Don't need to check busy - this should have gone. */
@@ -718,7 +714,6 @@ static int trace_kprobe_module_callback(struct notifier_block *nb, 
					module_name(mod), ret);

		}

	}

	mutex_unlock(&event_mutex);



	return NOTIFY_DONE;

}
@@ -1970,13 +1965,12 @@ static __init void enable_boot_kprobe_events(void) 
	struct trace_kprobe *tk;

	struct dyn_event *pos;



	mutex_lock(&event_mutex);

	guard(mutex)(&event_mutex);

	for_each_trace_kprobe(tk, pos) {

		list_for_each_entry(file, &tr->events, list)

			if (file->event_call == trace_probe_event_call(&tk->tp))

				trace_event_enable_disable(file, 1, 0);

	}

	mutex_unlock(&event_mutex);

}



static __init void setup_boot_kprobe_events(void)