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-rw-r--r--include/linux/tracepoint.h5
-rw-r--r--kernel/tracepoint.c14
2 files changed, 16 insertions, 3 deletions
diff --git a/include/linux/tracepoint.h b/include/linux/tracepoint.h
index 103d1b61aacb..a4a90b6726ce 100644
--- a/include/linux/tracepoint.h
+++ b/include/linux/tracepoint.h
@@ -17,6 +17,7 @@
17#include <linux/errno.h> 17#include <linux/errno.h>
18#include <linux/types.h> 18#include <linux/types.h>
19#include <linux/rcupdate.h> 19#include <linux/rcupdate.h>
20#include <linux/jump_label.h>
20 21
21struct module; 22struct module;
22struct tracepoint; 23struct tracepoint;
@@ -145,7 +146,9 @@ static inline void tracepoint_update_probe_range(struct tracepoint *begin,
145 extern struct tracepoint __tracepoint_##name; \ 146 extern struct tracepoint __tracepoint_##name; \
146 static inline void trace_##name(proto) \ 147 static inline void trace_##name(proto) \
147 { \ 148 { \
148 if (unlikely(__tracepoint_##name.state)) \ 149 JUMP_LABEL(&__tracepoint_##name.state, do_trace); \
150 return; \
151do_trace: \
149 __DO_TRACE(&__tracepoint_##name, \ 152 __DO_TRACE(&__tracepoint_##name, \
150 TP_PROTO(data_proto), \ 153 TP_PROTO(data_proto), \
151 TP_ARGS(data_args)); \ 154 TP_ARGS(data_args)); \
diff --git a/kernel/tracepoint.c b/kernel/tracepoint.c
index c77f3eceea25..d6073a50a6ca 100644
--- a/kernel/tracepoint.c
+++ b/kernel/tracepoint.c
@@ -25,6 +25,7 @@
25#include <linux/err.h> 25#include <linux/err.h>
26#include <linux/slab.h> 26#include <linux/slab.h>
27#include <linux/sched.h> 27#include <linux/sched.h>
28#include <linux/jump_label.h>
28 29
29extern struct tracepoint __start___tracepoints[]; 30extern struct tracepoint __start___tracepoints[];
30extern struct tracepoint __stop___tracepoints[]; 31extern struct tracepoint __stop___tracepoints[];
@@ -263,7 +264,13 @@ static void set_tracepoint(struct tracepoint_entry **entry,
263 * is used. 264 * is used.
264 */ 265 */
265 rcu_assign_pointer(elem->funcs, (*entry)->funcs); 266 rcu_assign_pointer(elem->funcs, (*entry)->funcs);
266 elem->state = active; 267 if (!elem->state && active) {
268 enable_jump_label(&elem->state);
269 elem->state = active;
270 } else if (elem->state && !active) {
271 disable_jump_label(&elem->state);
272 elem->state = active;
273 }
267} 274}
268 275
269/* 276/*
@@ -277,7 +284,10 @@ static void disable_tracepoint(struct tracepoint *elem)
277 if (elem->unregfunc && elem->state) 284 if (elem->unregfunc && elem->state)
278 elem->unregfunc(); 285 elem->unregfunc();
279 286
280 elem->state = 0; 287 if (elem->state) {
288 disable_jump_label(&elem->state);
289 elem->state = 0;
290 }
281 rcu_assign_pointer(elem->funcs, NULL); 291 rcu_assign_pointer(elem->funcs, NULL);
282} 292}
283 293