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Commit 715fa2fd authored by Masami Hiramatsu's avatar Masami Hiramatsu Committed by Steven Rostedt (VMware)
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tracing/kprobe: Check registered state using kprobe 

Change registered check only by trace_kprobe and remove
TP_FLAG_REGISTERED from trace_probe, since this feature
is only used for trace_kprobe.

Link: http://lkml.kernel.org/r/155931588704.28323.4952266828256245833.stgit@devnote2



Signed-off-by: default avatarMasami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: default avatarSteven Rostedt (VMware) <rostedt@goodmis.org>
parent e3dc9f89

kernel/trace/trace_kprobe.c

+15 −8
Original line number Diff line number Diff line
@@ -157,6 +157,12 @@ static nokprobe_inline unsigned long trace_kprobe_nhit(struct trace_kprobe *tk) 
	return nhit;

}



static nokprobe_inline bool trace_kprobe_is_registered(struct trace_kprobe *tk)

{

	return !(list_empty(&tk->rp.kp.list) &&

		 hlist_unhashed(&tk->rp.kp.hlist));

}



/* Return 0 if it fails to find the symbol address */

static nokprobe_inline

unsigned long trace_kprobe_address(struct trace_kprobe *tk)
@@ -244,6 +250,8 @@ static struct trace_kprobe *alloc_trace_kprobe(const char *group, 
		tk->rp.kp.pre_handler = kprobe_dispatcher;



	tk->rp.maxactive = maxactive;

	INIT_HLIST_NODE(&tk->rp.kp.hlist);

	INIT_LIST_HEAD(&tk->rp.kp.list);



	ret = trace_probe_init(&tk->tp, event, group);

	if (ret < 0)
@@ -273,7 +281,7 @@ static inline int __enable_trace_kprobe(struct trace_kprobe *tk) 
{

	int ret = 0;



	if (trace_probe_is_registered(&tk->tp) && !trace_kprobe_has_gone(tk)) {

	if (trace_kprobe_is_registered(tk) && !trace_kprobe_has_gone(tk)) {

		if (trace_kprobe_is_return(tk))

			ret = enable_kretprobe(&tk->rp);

		else
@@ -333,7 +341,7 @@ disable_trace_kprobe(struct trace_kprobe *tk, struct trace_event_file *file) 
	} else

		trace_probe_clear_flag(tp, TP_FLAG_PROFILE);



	if (!trace_probe_is_enabled(tp) && trace_probe_is_registered(tp)) {

	if (!trace_probe_is_enabled(tp) && trace_kprobe_is_registered(tk)) {

		if (trace_kprobe_is_return(tk))

			disable_kretprobe(&tk->rp);

		else
@@ -381,7 +389,7 @@ static int __register_trace_kprobe(struct trace_kprobe *tk) 
{

	int i, ret;



	if (trace_probe_is_registered(&tk->tp))

	if (trace_kprobe_is_registered(tk))

		return -EINVAL;



	if (within_notrace_func(tk)) {
@@ -407,21 +415,20 @@ static int __register_trace_kprobe(struct trace_kprobe *tk) 
	else

		ret = register_kprobe(&tk->rp.kp);



	if (ret == 0)

		trace_probe_set_flag(&tk->tp, TP_FLAG_REGISTERED);

	return ret;

}



/* Internal unregister function - just handle k*probes and flags */

static void __unregister_trace_kprobe(struct trace_kprobe *tk)

{

	if (trace_probe_is_registered(&tk->tp)) {

	if (trace_kprobe_is_registered(tk)) {

		if (trace_kprobe_is_return(tk))

			unregister_kretprobe(&tk->rp);

		else

			unregister_kprobe(&tk->rp.kp);

		trace_probe_clear_flag(&tk->tp, TP_FLAG_REGISTERED);

		/* Cleanup kprobe for reuse */

		/* Cleanup kprobe for reuse and mark it unregistered */

		INIT_HLIST_NODE(&tk->rp.kp.hlist);

		INIT_LIST_HEAD(&tk->rp.kp.list);

		if (tk->rp.kp.symbol_name)

			tk->rp.kp.addr = NULL;

	}

kernel/trace/trace_probe.h

+0 −6
Original line number Diff line number Diff line
@@ -55,7 +55,6 @@ 
/* Flags for trace_probe */

#define TP_FLAG_TRACE		1

#define TP_FLAG_PROFILE		2

#define TP_FLAG_REGISTERED	4



/* data_loc: data location, compatible with u32 */

#define make_data_loc(len, offs)	\
@@ -261,11 +260,6 @@ static inline bool trace_probe_is_enabled(struct trace_probe *tp) 
	return trace_probe_test_flag(tp, TP_FLAG_TRACE | TP_FLAG_PROFILE);

}



static inline bool trace_probe_is_registered(struct trace_probe *tp)

{

	return trace_probe_test_flag(tp, TP_FLAG_REGISTERED);

}



static inline const char *trace_probe_name(struct trace_probe *tp)

{

	return trace_event_name(&tp->call);