Merge branch 'tracing/ftrace' into auto-ftrace-next

Ingo Molnar
2 parents ec1bb60bbf b2613e370d
Showing 8 changed files Side-by-side Diff
include/linux/ftrace.h
kernel/Makefile
kernel/trace/ftrace.c
kernel/trace/trace.c
kernel/trace/trace.h
kernel/trace/trace_functions.c
kernel/trace/trace_sched_switch.c
kernel/trace/trace_sched_wakeup.c
@@ -89,6 +89,7 @@
  
 /* totally disable ftrace - can not re-enable after this */
 void ftrace_kill(void);
+void ftrace_kill_atomic(void);
  
 static inline void tracer_disable(void)
 {
@@ -11,7 +11,7 @@
 	    hrtimer.o rwsem.o nsproxy.o srcu.o semaphore.o \
 	    notifier.o ksysfs.o pm_qos_params.o sched_clock.o
  
-CFLAGS_REMOVE_sched.o = -pg -mno-spe
+CFLAGS_REMOVE_sched.o = -mno-spe
  
 ifdef CONFIG_FTRACE
 # Do not trace debug files and internal ftrace files
@@ -1602,6 +1602,23 @@
 #endif /* CONFIG_DYNAMIC_FTRACE */
  
 /**
+ * ftrace_kill_atomic - kill ftrace from critical sections
+ *
+ * This function should be used by panic code. It stops ftrace
+ * but in a not so nice way. If you need to simply kill ftrace
+ * from a non-atomic section, use ftrace_kill.
+ */
+void ftrace_kill_atomic(void)
+{
+	ftrace_disabled = 1;
+	ftrace_enabled = 0;
+#ifdef CONFIG_DYNAMIC_FTRACE
+	ftraced_suspend = -1;
+#endif
+	clear_ftrace_function();
+}
+
+/**
  * ftrace_kill - totally shutdown ftrace
  *
  * This is a safety measure. If something was detected that seems
@@ -96,6 +96,9 @@
 /* tracer_enabled is used to toggle activation of a tracer */
 static int			tracer_enabled = 1;
  
+/* function tracing enabled */
+int				ftrace_function_enabled;
+
 /*
  * trace_nr_entries is the number of entries that is allocated
  * for a buffer. Note, the number of entries is always rounded
@@ -134,6 +137,7 @@
 {
 	int cpu;
  
+	ftrace_function_enabled = 0;
 	if(tr->ctrl)
 		for_each_online_cpu(cpu)
 			tracing_reset(tr->data[cpu]);
@@ -1027,7 +1031,7 @@
 	long disabled;
 	int cpu;
  
-	if (unlikely(!tracer_enabled))
+	if (unlikely(!ftrace_function_enabled))
 		return;
  
 	if (skip_trace(ip))
  
  
@@ -1052,11 +1056,15 @@
  
 void tracing_start_function_trace(void)
 {
+	ftrace_function_enabled = 0;
 	register_ftrace_function(&trace_ops);
+	if (tracer_enabled)
+		ftrace_function_enabled = 1;
 }
  
 void tracing_stop_function_trace(void)
 {
+	ftrace_function_enabled = 0;
 	unregister_ftrace_function(&trace_ops);
 }
 #endif
@@ -1383,7 +1391,7 @@
 		   "server",
 #elif defined(CONFIG_PREEMPT_VOLUNTARY)
 		   "desktop",
-#elif defined(CONFIG_PREEMPT_DESKTOP)
+#elif defined(CONFIG_PREEMPT)
 		   "preempt",
 #else
 		   "unknown",
  
@@ -1892,8 +1900,10 @@
 		m->private = iter;
  
 		/* stop the trace while dumping */
-		if (iter->tr->ctrl)
+		if (iter->tr->ctrl) {
 			tracer_enabled = 0;
+			ftrace_function_enabled = 0;
+		}
  
 		if (iter->trace && iter->trace->open)
 			iter->trace->open(iter);
  
@@ -1926,8 +1936,14 @@
 		iter->trace->close(iter);
  
 	/* reenable tracing if it was previously enabled */
-	if (iter->tr->ctrl)
+	if (iter->tr->ctrl) {
 		tracer_enabled = 1;
+		/*
+		 * It is safe to enable function tracing even if it
+		 * isn't used
+		 */
+		ftrace_function_enabled = 1;
+	}
 	mutex_unlock(&trace_types_lock);
  
 	seq_release(inode, file);
@@ -223,8 +223,6 @@
 		    unsigned long parent_ip,
 		    unsigned long flags);
  
-void tracing_start_function_trace(void);
-void tracing_stop_function_trace(void);
 void tracing_start_cmdline_record(void);
 void tracing_stop_cmdline_record(void);
 int register_tracer(struct tracer *type);
@@ -240,6 +238,14 @@
 			  struct task_struct *tsk, int cpu);
  
 extern cycle_t ftrace_now(int cpu);
+
+#ifdef CONFIG_FTRACE
+void tracing_start_function_trace(void);
+void tracing_stop_function_trace(void);
+#else
+# define tracing_start_function_trace()		do { } while (0)
+# define tracing_stop_function_trace()		do { } while (0)
+#endif
  
 #ifdef CONFIG_CONTEXT_SWITCH_TRACER
 typedef void
@@ -28,7 +28,10 @@
  
 static void start_function_trace(struct trace_array *tr)
 {
+	tr->cpu = get_cpu();
 	function_reset(tr);
+	put_cpu();
+
 	tracing_start_cmdline_record();
 	tracing_start_function_trace();
 }
@@ -227,14 +227,14 @@
 static void start_sched_trace(struct trace_array *tr)
 {
 	sched_switch_reset(tr);
-	tracer_enabled = 1;
 	tracing_start_cmdline_record();
+	tracer_enabled = 1;
 }
  
 static void stop_sched_trace(struct trace_array *tr)
 {
-	tracing_stop_cmdline_record();
 	tracer_enabled = 0;
+	tracing_stop_cmdline_record();
 }
  
 static void sched_switch_trace_init(struct trace_array *tr)
@@ -352,8 +352,9 @@
 	 */
 	smp_wmb();
  
-	tracer_enabled = 1;
 	register_ftrace_function(&trace_ops);
+
+	tracer_enabled = 1;
  
 	return;
 fail_deprobe_wake_new:
...	...	@@ -89,6 +89,7 @@
89	89
90	90	/* totally disable ftrace - can not re-enable after this */
91	91	void ftrace_kill(void);
	92	+void ftrace_kill_atomic(void);
92	93
93	94	static inline void tracer_disable(void)
94	95	{
...	...	@@ -11,7 +11,7 @@
11	11	hrtimer.o rwsem.o nsproxy.o srcu.o semaphore.o \
12	12	notifier.o ksysfs.o pm_qos_params.o sched_clock.o
13	13
14		-CFLAGS_REMOVE_sched.o = -pg -mno-spe
	14	+CFLAGS_REMOVE_sched.o = -mno-spe
15	15
16	16	ifdef CONFIG_FTRACE
17	17	# Do not trace debug files and internal ftrace files
...	...	@@ -1602,6 +1602,23 @@
1602	1602	#endif /* CONFIG_DYNAMIC_FTRACE */
1603	1603
1604	1604	/**
	1605	+ * ftrace_kill_atomic - kill ftrace from critical sections
	1606	+ *
	1607	+ * This function should be used by panic code. It stops ftrace
	1608	+ * but in a not so nice way. If you need to simply kill ftrace
	1609	+ * from a non-atomic section, use ftrace_kill.
	1610	+ */
	1611	+void ftrace_kill_atomic(void)
	1612	+{
	1613	+ ftrace_disabled = 1;
	1614	+ ftrace_enabled = 0;
	1615	+#ifdef CONFIG_DYNAMIC_FTRACE
	1616	+ ftraced_suspend = -1;
	1617	+#endif
	1618	+ clear_ftrace_function();
	1619	+}
	1620	+
	1621	+/**
1605	1622	* ftrace_kill - totally shutdown ftrace
1606	1623	*
1607	1624	* This is a safety measure. If something was detected that seems
...	...	@@ -96,6 +96,9 @@
96	96	/* tracer_enabled is used to toggle activation of a tracer */
97	97	static int tracer_enabled = 1;
98	98
	99	+/* function tracing enabled */
	100	+int ftrace_function_enabled;
	101	+
99	102	/*
100	103	* trace_nr_entries is the number of entries that is allocated
101	104	* for a buffer. Note, the number of entries is always rounded
...	...	@@ -134,6 +137,7 @@
134	137	{
135	138	int cpu;
136	139
	140	+ ftrace_function_enabled = 0;
137	141	if(tr->ctrl)
138	142	for_each_online_cpu(cpu)
139	143	tracing_reset(tr->data[cpu]);
...	...	@@ -1027,7 +1031,7 @@
1027	1031	long disabled;
1028	1032	int cpu;
1029	1033
1030		- if (unlikely(!tracer_enabled))
	1034	+ if (unlikely(!ftrace_function_enabled))
1031	1035	return;
1032	1036
1033	1037	if (skip_trace(ip))
1034	1038
1035	1039
...	...	@@ -1052,11 +1056,15 @@
1052	1056
1053	1057	void tracing_start_function_trace(void)
1054	1058	{
	1059	+ ftrace_function_enabled = 0;
1055	1060	register_ftrace_function(&trace_ops);
	1061	+ if (tracer_enabled)
	1062	+ ftrace_function_enabled = 1;
1056	1063	}
1057	1064
1058	1065	void tracing_stop_function_trace(void)
1059	1066	{
	1067	+ ftrace_function_enabled = 0;
1060	1068	unregister_ftrace_function(&trace_ops);
1061	1069	}
1062	1070	#endif
...	...	@@ -1383,7 +1391,7 @@
1383	1391	"server",
1384	1392	#elif defined(CONFIG_PREEMPT_VOLUNTARY)
1385	1393	"desktop",
1386		-#elif defined(CONFIG_PREEMPT_DESKTOP)
	1394	+#elif defined(CONFIG_PREEMPT)
1387	1395	"preempt",
1388	1396	#else
1389	1397	"unknown",
1390	1398
...	...	@@ -1892,8 +1900,10 @@
1892	1900	m->private = iter;
1893	1901
1894	1902	/* stop the trace while dumping */
1895		- if (iter->tr->ctrl)
	1903	+ if (iter->tr->ctrl) {
1896	1904	tracer_enabled = 0;
	1905	+ ftrace_function_enabled = 0;
	1906	+ }
1897	1907
1898	1908	if (iter->trace && iter->trace->open)
1899	1909	iter->trace->open(iter);
1900	1910
...	...	@@ -1926,8 +1936,14 @@
1926	1936	iter->trace->close(iter);
1927	1937
1928	1938	/* reenable tracing if it was previously enabled */
1929		- if (iter->tr->ctrl)
	1939	+ if (iter->tr->ctrl) {
1930	1940	tracer_enabled = 1;
	1941	+ /*
	1942	+ * It is safe to enable function tracing even if it
	1943	+ * isn't used
	1944	+ */
	1945	+ ftrace_function_enabled = 1;
	1946	+ }
1931	1947	mutex_unlock(&trace_types_lock);
1932	1948
1933	1949	seq_release(inode, file);
...	...	@@ -223,8 +223,6 @@
223	223	unsigned long parent_ip,
224	224	unsigned long flags);
225	225
226		-void tracing_start_function_trace(void);
227		-void tracing_stop_function_trace(void);
228	226	void tracing_start_cmdline_record(void);
229	227	void tracing_stop_cmdline_record(void);
230	228	int register_tracer(struct tracer *type);
...	...	@@ -240,6 +238,14 @@
240	238	struct task_struct *tsk, int cpu);
241	239
242	240	extern cycle_t ftrace_now(int cpu);
	241	+
	242	+#ifdef CONFIG_FTRACE
	243	+void tracing_start_function_trace(void);
	244	+void tracing_stop_function_trace(void);
	245	+#else
	246	+# define tracing_start_function_trace() do { } while (0)
	247	+# define tracing_stop_function_trace() do { } while (0)
	248	+#endif
243	249
244	250	#ifdef CONFIG_CONTEXT_SWITCH_TRACER
245	251	typedef void
...	...	@@ -28,7 +28,10 @@
28	28
29	29	static void start_function_trace(struct trace_array *tr)
30	30	{
	31	+ tr->cpu = get_cpu();
31	32	function_reset(tr);
	33	+ put_cpu();
	34	+
32	35	tracing_start_cmdline_record();
33	36	tracing_start_function_trace();
34	37	}
...	...	@@ -227,14 +227,14 @@
227	227	static void start_sched_trace(struct trace_array *tr)
228	228	{
229	229	sched_switch_reset(tr);
230		- tracer_enabled = 1;
231	230	tracing_start_cmdline_record();
	231	+ tracer_enabled = 1;
232	232	}
233	233
234	234	static void stop_sched_trace(struct trace_array *tr)
235	235	{
236		- tracing_stop_cmdline_record();
237	236	tracer_enabled = 0;
	237	+ tracing_stop_cmdline_record();
238	238	}
239	239
240	240	static void sched_switch_trace_init(struct trace_array *tr)
...	...	@@ -352,8 +352,9 @@
352	352	*/
353	353	smp_wmb();
354	354
355		- tracer_enabled = 1;
356	355	register_ftrace_function(&trace_ops);
	356	+
	357	+ tracer_enabled = 1;
357	358
358	359	return;
359	360	fail_deprobe_wake_new: