Merge branches 'tracing/blktrace', 'tracing/ftrace' and 'tracing/urgent' into tracing/core

include/linux/ftrace.h

@@ -108,7 +108,7 @@ struct ftrace_func_command {
 
 struct seq_file;
 
-struct ftrace_hook_ops {
+struct ftrace_probe_ops {
 	void			(*func)(unsigned long ip,
 					unsigned long parent_ip,
 					void **data);
@@ -116,19 +116,19 @@ struct ftrace_hook_ops {
 	void			(*free)(void **data);
 	int			(*print)(struct seq_file *m,
 					 unsigned long ip,
-					 struct ftrace_hook_ops *ops,
+					 struct ftrace_probe_ops *ops,
 					 void *data);
 };
 
 extern int
-register_ftrace_function_hook(char *glob, struct ftrace_hook_ops *ops,
+register_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
 			      void *data);
 extern void
-unregister_ftrace_function_hook(char *glob, struct ftrace_hook_ops *ops,
+unregister_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
 				void *data);
 extern void
-unregister_ftrace_function_hook_func(char *glob, struct ftrace_hook_ops *ops);
-extern void unregister_ftrace_function_hook_all(char *glob);
+unregister_ftrace_function_probe_func(char *glob, struct ftrace_probe_ops *ops);
+extern void unregister_ftrace_function_probe_all(char *glob);
 
 enum {
 	FTRACE_FL_FREE		= (1 << 0),

kernel/trace/Kconfig

@@ -60,6 +60,7 @@ config FUNCTION_TRACER
 	depends on HAVE_FUNCTION_TRACER
 	depends on DEBUG_KERNEL
 	select FRAME_POINTER
+	select KALLSYMS
 	select TRACING
 	select CONTEXT_SWITCH_TRACER
 	help
@@ -246,6 +247,7 @@ config STACK_TRACER
 	depends on DEBUG_KERNEL
 	select FUNCTION_TRACER
 	select STACKTRACE
+	select KALLSYMS
 	help
 	  This special tracer records the maximum stack footprint of the
 	  kernel and displays it in debugfs/tracing/stack_trace.

kernel/trace/ftrace.c

@@ -255,9 +255,9 @@ static struct pid * const ftrace_swapper_pid = &init_struct_pid;
 
 static struct hlist_head ftrace_func_hash[FTRACE_FUNC_HASHSIZE] __read_mostly;
 
-struct ftrace_func_hook {
+struct ftrace_func_probe {
 	struct hlist_node	node;
-	struct ftrace_hook_ops	*ops;
+	struct ftrace_probe_ops	*ops;
 	unsigned long		flags;
 	unsigned long		ip;
 	void			*data;
@@ -460,8 +460,8 @@ static void ftrace_bug(int failed, unsigned long ip)
 static int
 __ftrace_replace_code(struct dyn_ftrace *rec, int enable)
 {
-	unsigned long ip, fl;
 	unsigned long ftrace_addr;
+	unsigned long ip, fl;
 
 	ftrace_addr = (unsigned long)FTRACE_ADDR;
 
@@ -530,9 +530,9 @@ __ftrace_replace_code(struct dyn_ftrace *rec, int enable)
 
 static void ftrace_replace_code(int enable)
 {
-	int failed;
 	struct dyn_ftrace *rec;
 	struct ftrace_page *pg;
+	int failed;
 
 	do_for_each_ftrace_rec(pg, rec) {
 		/*
@@ -830,11 +830,11 @@ static void *t_hash_start(struct seq_file *m, loff_t *pos)
 
 static int t_hash_show(struct seq_file *m, void *v)
 {
-	struct ftrace_func_hook *rec;
+	struct ftrace_func_probe *rec;
 	struct hlist_node *hnd = v;
 	char str[KSYM_SYMBOL_LEN];
 
-	rec = hlist_entry(hnd, struct ftrace_func_hook, node);
+	rec = hlist_entry(hnd, struct ftrace_func_probe, node);
 
 	if (rec->ops->print)
 		return rec->ops->print(m, rec->ip, rec->ops, rec->data);
@@ -1208,14 +1208,15 @@ ftrace_match_record(struct dyn_ftrace *rec, char *regex, int len, int type)
 
 static void ftrace_match_records(char *buff, int len, int enable)
 {
-	char *search;
+	unsigned int search_len;
 	struct ftrace_page *pg;
 	struct dyn_ftrace *rec;
+	unsigned long flag;
+	char *search;
 	int type;
-	unsigned long flag = enable ? FTRACE_FL_FILTER : FTRACE_FL_NOTRACE;
-	unsigned search_len;
 	int not;
 
+	flag = enable ? FTRACE_FL_FILTER : FTRACE_FL_NOTRACE;
 	type = ftrace_setup_glob(buff, len, &search, &not);
 
 	search_len = strlen(search);
@@ -1263,14 +1264,16 @@ ftrace_match_module_record(struct dyn_ftrace *rec, char *mod,
 
 static void ftrace_match_module_records(char *buff, char *mod, int enable)
 {
-	char *search = buff;
+	unsigned search_len = 0;
 	struct ftrace_page *pg;
 	struct dyn_ftrace *rec;
 	int type = MATCH_FULL;
-	unsigned long flag = enable ? FTRACE_FL_FILTER : FTRACE_FL_NOTRACE;
-	unsigned search_len = 0;
+	char *search = buff;
+	unsigned long flag;
 	int not = 0;
 
+	flag = enable ? FTRACE_FL_FILTER : FTRACE_FL_NOTRACE;
+
 	/* blank or '*' mean the same */
 	if (strcmp(buff, "*") == 0)
 		buff[0] = 0;
@@ -1348,9 +1351,9 @@ static int __init ftrace_mod_cmd_init(void)
 device_initcall(ftrace_mod_cmd_init);
 
 static void
-function_trace_hook_call(unsigned long ip, unsigned long parent_ip)
+function_trace_probe_call(unsigned long ip, unsigned long parent_ip)
 {
-	struct ftrace_func_hook *entry;
+	struct ftrace_func_probe *entry;
 	struct hlist_head *hhd;
 	struct hlist_node *n;
 	unsigned long key;
@@ -1376,18 +1379,18 @@ function_trace_hook_call(unsigned long ip, unsigned long parent_ip)
 	ftrace_preempt_enable(resched);
 }
 
-static struct ftrace_ops trace_hook_ops __read_mostly =
+static struct ftrace_ops trace_probe_ops __read_mostly =
 {
-	.func = function_trace_hook_call,
+	.func = function_trace_probe_call,
 };
 
-static int ftrace_hook_registered;
+static int ftrace_probe_registered;
 
-static void __enable_ftrace_function_hook(void)
+static void __enable_ftrace_function_probe(void)
 {
 	int i;
 
-	if (ftrace_hook_registered)
+	if (ftrace_probe_registered)
 		return;
 
 	for (i = 0; i < FTRACE_FUNC_HASHSIZE; i++) {
@@ -1399,16 +1402,16 @@ static void __enable_ftrace_function_hook(void)
 	if (i == FTRACE_FUNC_HASHSIZE)
 		return;
 
-	__register_ftrace_function(&trace_hook_ops);
+	__register_ftrace_function(&trace_probe_ops);
 	ftrace_startup(0);
-	ftrace_hook_registered = 1;
+	ftrace_probe_registered = 1;
 }
 
-static void __disable_ftrace_function_hook(void)
+static void __disable_ftrace_function_probe(void)
 {
 	int i;
 
-	if (!ftrace_hook_registered)
+	if (!ftrace_probe_registered)
 		return;
 
 	for (i = 0; i < FTRACE_FUNC_HASHSIZE; i++) {
@@ -1418,16 +1421,16 @@ static void __disable_ftrace_function_hook(void)
 	}
 
 	/* no more funcs left */
-	__unregister_ftrace_function(&trace_hook_ops);
+	__unregister_ftrace_function(&trace_probe_ops);
 	ftrace_shutdown(0);
-	ftrace_hook_registered = 0;
+	ftrace_probe_registered = 0;
 }
 
 
 static void ftrace_free_entry_rcu(struct rcu_head *rhp)
 {
-	struct ftrace_func_hook *entry =
-		container_of(rhp, struct ftrace_func_hook, rcu);
+	struct ftrace_func_probe *entry =
+		container_of(rhp, struct ftrace_func_probe, rcu);
 
 	if (entry->ops->free)
 		entry->ops->free(&entry->data);
@@ -1436,21 +1439,21 @@ static void ftrace_free_entry_rcu(struct rcu_head *rhp)
 
 
 int
-register_ftrace_function_hook(char *glob, struct ftrace_hook_ops *ops,
+register_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
 			      void *data)
 {
-	struct ftrace_func_hook *entry;
+	struct ftrace_func_probe *entry;
 	struct ftrace_page *pg;
 	struct dyn_ftrace *rec;
-	unsigned long key;
 	int type, len, not;
+	unsigned long key;
 	int count = 0;
 	char *search;
 
 	type = ftrace_setup_glob(glob, strlen(glob), &search, &not);
 	len = strlen(search);
 
-	/* we do not support '!' for function hooks */
+	/* we do not support '!' for function probes */
 	if (WARN_ON(not))
 		return -EINVAL;
 
@@ -1465,7 +1468,7 @@ register_ftrace_function_hook(char *glob, struct ftrace_hook_ops *ops,
 
 		entry = kmalloc(sizeof(*entry), GFP_KERNEL);
 		if (!entry) {
-			/* If we did not hook to any, then return error */
+			/* If we did not process any, then return error */
 			if (!count)
 				count = -ENOMEM;
 			goto out_unlock;
@@ -1495,7 +1498,7 @@ register_ftrace_function_hook(char *glob, struct ftrace_hook_ops *ops,
 		hlist_add_head_rcu(&entry->node, &ftrace_func_hash[key]);
 
 	} while_for_each_ftrace_rec();
-	__enable_ftrace_function_hook();
+	__enable_ftrace_function_probe();
 
  out_unlock:
 	mutex_unlock(&ftrace_lock);
@@ -1504,15 +1507,15 @@ register_ftrace_function_hook(char *glob, struct ftrace_hook_ops *ops,
 }
 
 enum {
-	HOOK_TEST_FUNC		= 1,
-	HOOK_TEST_DATA		= 2
+	PROBE_TEST_FUNC		= 1,
+	PROBE_TEST_DATA		= 2
 };
 
 static void
-__unregister_ftrace_function_hook(char *glob, struct ftrace_hook_ops *ops,
+__unregister_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
 				  void *data, int flags)
 {
-	struct ftrace_func_hook *entry;
+	struct ftrace_func_probe *entry;
 	struct hlist_node *n, *tmp;
 	char str[KSYM_SYMBOL_LEN];
 	int type = MATCH_FULL;
@@ -1527,7 +1530,7 @@ __unregister_ftrace_function_hook(char *glob, struct ftrace_hook_ops *ops,
 		type = ftrace_setup_glob(glob, strlen(glob), &search, &not);
 		len = strlen(search);
 
-		/* we do not support '!' for function hooks */
+		/* we do not support '!' for function probes */
 		if (WARN_ON(not))
 			return;
 	}
@@ -1539,10 +1542,10 @@ __unregister_ftrace_function_hook(char *glob, struct ftrace_hook_ops *ops,
 		hlist_for_each_entry_safe(entry, n, tmp, hhd, node) {
 
 			/* break up if statements for readability */
-			if ((flags & HOOK_TEST_FUNC) && entry->ops != ops)
+			if ((flags & PROBE_TEST_FUNC) && entry->ops != ops)
 				continue;
 
-			if ((flags & HOOK_TEST_DATA) && entry->data != data)
+			if ((flags & PROBE_TEST_DATA) && entry->data != data)
 				continue;
 
 			/* do this last, since it is the most expensive */
@@ -1557,27 +1560,27 @@ __unregister_ftrace_function_hook(char *glob, struct ftrace_hook_ops *ops,
 			call_rcu(&entry->rcu, ftrace_free_entry_rcu);
 		}
 	}
-	__disable_ftrace_function_hook();
+	__disable_ftrace_function_probe();
 	mutex_unlock(&ftrace_lock);
 }
 
 void
-unregister_ftrace_function_hook(char *glob, struct ftrace_hook_ops *ops,
+unregister_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
 				void *data)
 {
-	__unregister_ftrace_function_hook(glob, ops, data,
-					  HOOK_TEST_FUNC | HOOK_TEST_DATA);
+	__unregister_ftrace_function_probe(glob, ops, data,
+					  PROBE_TEST_FUNC | PROBE_TEST_DATA);
 }
 
 void
-unregister_ftrace_function_hook_func(char *glob, struct ftrace_hook_ops *ops)
+unregister_ftrace_function_probe_func(char *glob, struct ftrace_probe_ops *ops)
 {
-	__unregister_ftrace_function_hook(glob, ops, NULL, HOOK_TEST_FUNC);
+	__unregister_ftrace_function_probe(glob, ops, NULL, PROBE_TEST_FUNC);
 }
 
-void unregister_ftrace_function_hook_all(char *glob)
+void unregister_ftrace_function_probe_all(char *glob)
 {
-	__unregister_ftrace_function_hook(glob, NULL, NULL, 0);
+	__unregister_ftrace_function_probe(glob, NULL, NULL, 0);
 }
 
 static LIST_HEAD(ftrace_commands);
@@ -1623,8 +1626,8 @@ int unregister_ftrace_command(struct ftrace_func_command *cmd)
 
 static int ftrace_process_regex(char *buff, int len, int enable)
 {
-	struct ftrace_func_command *p;
 	char *func, *command, *next = buff;
+	struct ftrace_func_command *p;
 	int ret = -EINVAL;
 
 	func = strsep(&next, ":");
@@ -2392,7 +2395,6 @@ static __init int ftrace_init_debugfs(void)
 			   "'set_ftrace_pid' entry\n");
 	return 0;
 }
-
 fs_initcall(ftrace_init_debugfs);
 
 /**

kernel/trace/trace.c

@@ -336,7 +336,7 @@ __update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu)
 	data->rt_priority = tsk->rt_priority;
 
 	/* record this tasks comm */
-	tracing_record_cmdline(current);
+	tracing_record_cmdline(tsk);
 }
 
 static void
@@ -499,6 +499,9 @@ __acquires(kernel_lock)
 	else
 		if (!type->flags->opts)
 			type->flags->opts = dummy_tracer_opt;
+	if (!type->wait_pipe)
+		type->wait_pipe = default_wait_pipe;
+
 
 #ifdef CONFIG_FTRACE_STARTUP_TEST
 	if (type->selftest && !tracing_selftest_disabled) {
@@ -1064,7 +1067,10 @@ tracing_sched_wakeup_trace(struct trace_array *tr,
 	entry->next_prio		= wakee->prio;
 	entry->next_state		= wakee->state;
 	entry->next_cpu			= task_cpu(wakee);
-	trace_buffer_unlock_commit(tr, event, flags, pc);
+
+	ring_buffer_unlock_commit(tr->buffer, event);
+	ftrace_trace_stack(tr, flags, 6, pc);
+	ftrace_trace_userstack(tr, flags, pc);
 }
 
 void
@@ -2392,6 +2398,38 @@ tracing_poll_pipe(struct file *filp, poll_table *poll_table)
 	}
 }
 
+
+void default_wait_pipe(struct trace_iterator *iter)
+{
+	DEFINE_WAIT(wait);
+
+	prepare_to_wait(&trace_wait, &wait, TASK_INTERRUPTIBLE);
+
+	if (trace_empty(iter))
+		schedule();
+
+	finish_wait(&trace_wait, &wait);
+}
+
+/*
+ * This is a make-shift waitqueue.
+ * A tracer might use this callback on some rare cases:
+ *
+ *  1) the current tracer might hold the runqueue lock when it wakes up
+ *     a reader, hence a deadlock (sched, function, and function graph tracers)
+ *  2) the function tracers, trace all functions, we don't want
+ *     the overhead of calling wake_up and friends
+ *     (and tracing them too)
+ *
+ *     Anyway, this is really very primitive wakeup.
+ */
+void poll_wait_pipe(struct trace_iterator *iter)
+{
+	set_current_state(TASK_INTERRUPTIBLE);
+	/* sleep for 100 msecs, and try again. */
+	schedule_timeout(HZ / 10);
+}
+
 /* Must be called with trace_types_lock mutex held. */
 static int tracing_wait_pipe(struct file *filp)
 {
@@ -2403,30 +2441,14 @@ static int tracing_wait_pipe(struct file *filp)
 			return -EAGAIN;
 		}
 
-		/*
-		 * This is a make-shift waitqueue. The reason we don't use
-		 * an actual wait queue is because:
-		 *  1) we only ever have one waiter
-		 *  2) the tracing, traces all functions, we don't want
-		 *     the overhead of calling wake_up and friends
-		 *     (and tracing them too)
-		 *     Anyway, this is really very primitive wakeup.
-		 */
-		set_current_state(TASK_INTERRUPTIBLE);
-		iter->tr->waiter = current;
-
 		mutex_unlock(&trace_types_lock);
 
-		/* sleep for 100 msecs, and try again. */
-		schedule_timeout(HZ/10);
+		iter->trace->wait_pipe(iter);
 
 		mutex_lock(&trace_types_lock);
 
-		iter->tr->waiter = NULL;
-
-		if (signal_pending(current)) {
+		if (signal_pending(current))
 			return -EINTR;
-		}
 
 		if (iter->trace != current_trace)
 			return 0;
@@ -2442,8 +2464,6 @@ static int tracing_wait_pipe(struct file *filp)
 		 */
 		if (!tracer_enabled && iter->pos)
 			break;
-
-		continue;
 	}
 
 	return 1;
@@ -2551,8 +2571,7 @@ static struct pipe_buf_operations tracing_pipe_buf_ops = {
 };
 
 static size_t
-tracing_fill_pipe_page(struct page *pages, size_t rem,
-			struct trace_iterator *iter)
+tracing_fill_pipe_page(size_t rem, struct trace_iterator *iter)
 {
 	size_t count;
 	int ret;
@@ -2629,7 +2648,7 @@ static ssize_t tracing_splice_read_pipe(struct file *filp,
 		if (!pages[i])
 			break;
 
-		rem = tracing_fill_pipe_page(pages[i], rem, iter);
+		rem = tracing_fill_pipe_page(rem, iter);
 
 		/* Copy the data into the page, so we can start over. */
 		ret = trace_seq_to_buffer(&iter->seq,

kernel/trace/trace.h

@@ -337,18 +337,34 @@ struct tracer_flags {
 #define TRACER_OPT(s, b)	.name = #s, .bit = b
 
 
-/*
- * A specific tracer, represented by methods that operate on a trace array:
+/**
+ * struct tracer - a specific tracer and its callbacks to interact with debugfs
+ * @name: the name chosen to select it on the available_tracers file
+ * @init: called when one switches to this tracer (echo name > current_tracer)
+ * @reset: called when one switches to another tracer
+ * @start: called when tracing is unpaused (echo 1 > tracing_enabled)
+ * @stop: called when tracing is paused (echo 0 > tracing_enabled)
+ * @open: called when the trace file is opened
+ * @pipe_open: called when the trace_pipe file is opened
+ * @wait_pipe: override how the user waits for traces on trace_pipe
+ * @close: called when the trace file is released
+ * @read: override the default read callback on trace_pipe
+ * @splice_read: override the default splice_read callback on trace_pipe
+ * @selftest: selftest to run on boot (see trace_selftest.c)
+ * @print_headers: override the first lines that describe your columns
+ * @print_line: callback that prints a trace
+ * @set_flag: signals one of your private flags changed (trace_options file)
+ * @flags: your private flags
  */
 struct tracer {
 	const char		*name;
-	/* Your tracer should raise a warning if init fails */
 	int			(*init)(struct trace_array *tr);
 	void			(*reset)(struct trace_array *tr);
 	void			(*start)(struct trace_array *tr);
 	void			(*stop)(struct trace_array *tr);
 	void			(*open)(struct trace_iterator *iter);
 	void			(*pipe_open)(struct trace_iterator *iter);
+	void			(*wait_pipe)(struct trace_iterator *iter);
 	void			(*close)(struct trace_iterator *iter);
 	ssize_t			(*read)(struct trace_iterator *iter,
 					struct file *filp, char __user *ubuf,
@@ -432,6 +448,9 @@ void tracing_generic_entry_update(struct trace_entry *entry,
 				  unsigned long flags,
 				  int pc);
 
+void default_wait_pipe(struct trace_iterator *iter);
+void poll_wait_pipe(struct trace_iterator *iter);
+
 void ftrace(struct trace_array *tr,
 			    struct trace_array_cpu *data,
 			    unsigned long ip,

kernel/trace/trace_functions.c

@@ -225,6 +225,7 @@ static struct tracer function_trace __read_mostly =
 	.init		= function_trace_init,
 	.reset		= function_trace_reset,
 	.start		= function_trace_start,
+	.wait_pipe	= poll_wait_pipe,
 	.flags		= &func_flags,
 	.set_flag	= func_set_flag,
 #ifdef CONFIG_FTRACE_SELFTEST
@@ -269,21 +270,21 @@ ftrace_traceoff(unsigned long ip, unsigned long parent_ip, void **data)
 
 static int
 ftrace_trace_onoff_print(struct seq_file *m, unsigned long ip,
-			 struct ftrace_hook_ops *ops, void *data);
+			 struct ftrace_probe_ops *ops, void *data);
 
-static struct ftrace_hook_ops traceon_hook_ops = {
+static struct ftrace_probe_ops traceon_probe_ops = {
 	.func			= ftrace_traceon,
 	.print			= ftrace_trace_onoff_print,
 };
 
-static struct ftrace_hook_ops traceoff_hook_ops = {
+static struct ftrace_probe_ops traceoff_probe_ops = {
 	.func			= ftrace_traceoff,
 	.print			= ftrace_trace_onoff_print,
 };
 
 static int
 ftrace_trace_onoff_print(struct seq_file *m, unsigned long ip,
-			 struct ftrace_hook_ops *ops, void *data)
+			 struct ftrace_probe_ops *ops, void *data)
 {
 	char str[KSYM_SYMBOL_LEN];
 	long count = (long)data;
@@ -291,12 +292,14 @@ ftrace_trace_onoff_print(struct seq_file *m, unsigned long ip,
 	kallsyms_lookup(ip, NULL, NULL, NULL, str);
 	seq_printf(m, "%s:", str);
 
-	if (ops == &traceon_hook_ops)
+	if (ops == &traceon_probe_ops)
 		seq_printf(m, "traceon");
 	else
 		seq_printf(m, "traceoff");
 
-	if (count != -1)
+	if (count == -1)
+		seq_printf(m, ":unlimited\n");
+	else
 		seq_printf(m, ":count=%ld", count);
 	seq_putc(m, '\n');
 
@@ -306,15 +309,15 @@ ftrace_trace_onoff_print(struct seq_file *m, unsigned long ip,
 static int
 ftrace_trace_onoff_unreg(char *glob, char *cmd, char *param)
 {
-	struct ftrace_hook_ops *ops;
+	struct ftrace_probe_ops *ops;
 
 	/* we register both traceon and traceoff to this callback */
 	if (strcmp(cmd, "traceon") == 0)
-		ops = &traceon_hook_ops;
+		ops = &traceon_probe_ops;
 	else
-		ops = &traceoff_hook_ops;
+		ops = &traceoff_probe_ops;
 
-	unregister_ftrace_function_hook_func(glob, ops);
+	unregister_ftrace_function_probe_func(glob, ops);
 
 	return 0;
 }
@@ -322,7 +325,7 @@ ftrace_trace_onoff_unreg(char *glob, char *cmd, char *param)
 static int
 ftrace_trace_onoff_callback(char *glob, char *cmd, char *param, int enable)
 {
-	struct ftrace_hook_ops *ops;
+	struct ftrace_probe_ops *ops;
 	void *count = (void *)-1;
 	char *number;
 	int ret;
@@ -336,9 +339,9 @@ ftrace_trace_onoff_callback(char *glob, char *cmd, char *param, int enable)
 
 	/* we register both traceon and traceoff to this callback */
 	if (strcmp(cmd, "traceon") == 0)
-		ops = &traceon_hook_ops;
+		ops = &traceon_probe_ops;
 	else
-		ops = &traceoff_hook_ops;
+		ops = &traceoff_probe_ops;
 
 	if (!param)
 		goto out_reg;
@@ -357,7 +360,7 @@ ftrace_trace_onoff_callback(char *glob, char *cmd, char *param, int enable)
 		return ret;
 
  out_reg:
-	ret = register_ftrace_function_hook(glob, ops, count);
+	ret = register_ftrace_function_probe(glob, ops, count);
 
 	return ret;
 }
@@ -397,6 +400,5 @@ static __init int init_function_trace(void)
 	init_func_cmd_traceon();
 	return register_tracer(&function_trace);
 }
-
 device_initcall(init_function_trace);
 

kernel/trace/trace_functions_graph.c

@@ -757,6 +757,7 @@ static struct tracer graph_trace __read_mostly = {
 	.name	     	= "function_graph",
 	.open		= graph_trace_open,
 	.close		= graph_trace_close,
+	.wait_pipe	= poll_wait_pipe,
 	.init	     	= graph_trace_init,
 	.reset	     	= graph_trace_reset,
 	.print_line	= print_graph_function,

kernel/trace/trace_irqsoff.c

@@ -1,5 +1,5 @@
 /*
- * trace irqs off criticall timings
+ * trace irqs off critical timings
  *
  * Copyright (C) 2007-2008 Steven Rostedt <srostedt@redhat.com>
  * Copyright (C) 2008 Ingo Molnar <mingo@redhat.com>

kernel/trace/trace_sched_switch.c

@@ -93,7 +93,7 @@ static int tracing_sched_register(void)
 	ret = register_trace_sched_switch(probe_sched_switch);
 	if (ret) {
 		pr_info("sched trace: Couldn't activate tracepoint"
-			" probe to kernel_sched_schedule\n");
+			" probe to kernel_sched_switch\n");
 		goto fail_deprobe_wake_new;
 	}
 
@@ -221,6 +221,7 @@ static struct tracer sched_switch_trace __read_mostly =
 	.reset		= sched_switch_trace_reset,
 	.start		= sched_switch_trace_start,
 	.stop		= sched_switch_trace_stop,
+	.wait_pipe	= poll_wait_pipe,
 #ifdef CONFIG_FTRACE_SELFTEST
 	.selftest    = trace_selftest_startup_sched_switch,
 #endif

kernel/trace/trace_sched_wakeup.c

@@ -284,7 +284,7 @@ static void start_wakeup_tracer(struct trace_array *tr)
 	ret = register_trace_sched_switch(probe_wakeup_sched_switch);
 	if (ret) {
 		pr_info("sched trace: Couldn't activate tracepoint"
-			" probe to kernel_sched_schedule\n");
+			" probe to kernel_sched_switch\n");
 		goto fail_deprobe_wake_new;
 	}
 
@@ -380,6 +380,7 @@ static struct tracer wakeup_rt_tracer __read_mostly =
 	.reset		= wakeup_tracer_reset,
 	.start		= wakeup_tracer_start,
 	.stop		= wakeup_tracer_stop,
+	.wait_pipe	= poll_wait_pipe,
 	.print_max	= 1,
 #ifdef CONFIG_FTRACE_SELFTEST
 	.selftest    = trace_selftest_startup_wakeup,

kernel/trace/trace_selftest.c

@@ -24,10 +24,20 @@ static int trace_test_buffer_cpu(struct trace_array *tr, int cpu)
 {
 	struct ring_buffer_event *event;
 	struct trace_entry *entry;
+	unsigned int loops = 0;
 
 	while ((event = ring_buffer_consume(tr->buffer, cpu, NULL))) {
 		entry = ring_buffer_event_data(event);
 
+		/*
+		 * The ring buffer is a size of trace_buf_size, if
+		 * we loop more than the size, there's something wrong
+		 * with the ring buffer.
+		 */
+		if (loops++ > trace_buf_size) {
+			printk(KERN_CONT ".. bad ring buffer ");
+			goto failed;
+		}
 		if (!trace_valid_entry(entry)) {
 			printk(KERN_CONT ".. invalid entry %d ",
 				entry->type);
@@ -58,11 +68,20 @@ static int trace_test_buffer(struct trace_array *tr, unsigned long *count)
 
 	cnt = ring_buffer_entries(tr->buffer);
 
+	/*
+	 * The trace_test_buffer_cpu runs a while loop to consume all data.
+	 * If the calling tracer is broken, and is constantly filling
+	 * the buffer, this will run forever, and hard lock the box.
+	 * We disable the ring buffer while we do this test to prevent
+	 * a hard lock up.
+	 */
+	tracing_off();
 	for_each_possible_cpu(cpu) {
 		ret = trace_test_buffer_cpu(tr, cpu);
 		if (ret)
 			break;
 	}
+	tracing_on();
 	__raw_spin_unlock(&ftrace_max_lock);
 	local_irq_restore(flags);
 
@@ -107,9 +126,9 @@ int trace_selftest_startup_dynamic_tracing(struct tracer *trace,
 	func();
 
 	/*
-	 * Some archs *cough*PowerPC*cough* add charachters to the
+	 * Some archs *cough*PowerPC*cough* add characters to the
 	 * start of the function names. We simply put a '*' to
-	 * accomodate them.
+	 * accommodate them.
 	 */
 	func_name = "*" STR(DYN_FTRACE_TEST_NAME);
 
@@ -622,7 +641,7 @@ trace_selftest_startup_sysprof(struct tracer *trace, struct trace_array *tr)
 	ret = tracer_init(trace, tr);
 	if (ret) {
 		warn_failed_init_tracer(trace, ret);
-		return 0;
+		return ret;
 	}
 
 	/* Sleep for a 1/10 of a second */
@@ -634,6 +653,11 @@ trace_selftest_startup_sysprof(struct tracer *trace, struct trace_array *tr)
 	trace->reset(tr);
 	tracing_start();
 
+	if (!ret && !count) {
+		printk(KERN_CONT ".. no entries found ..");
+		ret = -1;
+	}
+
 	return ret;
 }
 #endif /* CONFIG_SYSPROF_TRACER */
@@ -661,6 +685,11 @@ trace_selftest_startup_branch(struct tracer *trace, struct trace_array *tr)
 	trace->reset(tr);
 	tracing_start();
 
+	if (!ret && !count) {
+		printk(KERN_CONT ".. no entries found ..");
+		ret = -1;
+	}
+
 	return ret;
 }
 #endif /* CONFIG_BRANCH_TRACER */

kernel/trace/trace_stat.c

@@ -30,7 +30,7 @@ struct tracer_stat_session {
 	struct dentry		*file;
 };
 
-/* All of the sessions currently in use. Each stat file embeed one session */
+/* All of the sessions currently in use. Each stat file embed one session */
 static LIST_HEAD(all_stat_sessions);
 static DEFINE_MUTEX(all_stat_sessions_mutex);
 

kernel/trace/trace_sysprof.c

@@ -327,5 +327,5 @@ void init_tracer_sysprof_debugfs(struct dentry *d_tracer)
 			d_tracer, NULL, &sysprof_sample_fops);
 	if (entry)
 		return;
-	pr_warning("Could not create debugfs 'dyn_ftrace_total_info' entry\n");
+	pr_warning("Could not create debugfs 'sysprof_sample_period' entry\n");
 }