1 files changed, 367 insertions, 154 deletions

diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 091e801145c9..752e5daf0896 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -87,7 +87,7 @@ dummy_set_flag(struct trace_array *tr, u32 old_flags, u32 bit, int set)
  * tracing is active, only save the comm when a trace event
  * occurred.
  */
-static DEFINE_PER_CPU(bool, trace_cmdline_save);
+static DEFINE_PER_CPU(bool, trace_taskinfo_save);
 
 /*
  * Kill all tracing for good (never come back).
@@ -120,41 +120,41 @@ enum ftrace_dump_mode ftrace_dump_on_oops;
 /* When set, tracing will stop when a WARN*() is hit */
 int __disable_trace_on_warning;
 
-#ifdef CONFIG_TRACE_ENUM_MAP_FILE
-/* Map of enums to their values, for "enum_map" file */
-struct trace_enum_map_head {
+#ifdef CONFIG_TRACE_EVAL_MAP_FILE
+/* Map of enums to their values, for "eval_map" file */
+struct trace_eval_map_head {
 	struct module			*mod;
 	unsigned long			length;
 };
 
-union trace_enum_map_item;
+union trace_eval_map_item;
 
-struct trace_enum_map_tail {
+struct trace_eval_map_tail {
 	/*
 	 * "end" is first and points to NULL as it must be different
-	 * than "mod" or "enum_string"
+	 * than "mod" or "eval_string"
 	 */
-	union trace_enum_map_item	*next;
+	union trace_eval_map_item	*next;
 	const char			*end;	/* points to NULL */
 };
 
-static DEFINE_MUTEX(trace_enum_mutex);
+static DEFINE_MUTEX(trace_eval_mutex);
 
 /*
- * The trace_enum_maps are saved in an array with two extra elements,
+ * The trace_eval_maps are saved in an array with two extra elements,
  * one at the beginning, and one at the end. The beginning item contains
  * the count of the saved maps (head.length), and the module they
  * belong to if not built in (head.mod). The ending item contains a
- * pointer to the next array of saved enum_map items.
+ * pointer to the next array of saved eval_map items.
  */
-union trace_enum_map_item {
-	struct trace_enum_map		map;
-	struct trace_enum_map_head	head;
-	struct trace_enum_map_tail	tail;
+union trace_eval_map_item {
+	struct trace_eval_map		map;
+	struct trace_eval_map_head	head;
+	struct trace_eval_map_tail	tail;
 };
 
-static union trace_enum_map_item *trace_enum_maps;
-#endif /* CONFIG_TRACE_ENUM_MAP_FILE */
+static union trace_eval_map_item *trace_eval_maps;
+#endif /* CONFIG_TRACE_EVAL_MAP_FILE */
 
 static int tracing_set_tracer(struct trace_array *tr, const char *buf);
 
@@ -790,7 +790,7 @@ EXPORT_SYMBOL_GPL(tracing_on);
 static __always_inline void
 __buffer_unlock_commit(struct ring_buffer *buffer, struct ring_buffer_event *event)
 {
-	__this_cpu_write(trace_cmdline_save, true);
+	__this_cpu_write(trace_taskinfo_save, true);
 
 	/* If this is the temp buffer, we need to commit fully */
 	if (this_cpu_read(trace_buffered_event) == event) {
@@ -1141,9 +1141,9 @@ unsigned long nsecs_to_usecs(unsigned long nsecs)
 
 /*
  * TRACE_FLAGS is defined as a tuple matching bit masks with strings.
- * It uses C(a, b) where 'a' is the enum name and 'b' is the string that
+ * It uses C(a, b) where 'a' is the eval (enum) name and 'b' is the string that
  * matches it. By defining "C(a, b) b", TRACE_FLAGS becomes a list
- * of strings in the order that the enums were defined.
+ * of strings in the order that the evals (enum) were defined.
  */
 #undef C
 #define C(a, b) b
@@ -1702,6 +1702,9 @@ void tracing_reset_all_online_cpus(void)
 	struct trace_array *tr;
 
 	list_for_each_entry(tr, &ftrace_trace_arrays, list) {
+		if (!tr->clear_trace)
+			continue;
+		tr->clear_trace = false;
 		tracing_reset_online_cpus(&tr->trace_buffer);
 #ifdef CONFIG_TRACER_MAX_TRACE
 		tracing_reset_online_cpus(&tr->max_buffer);
@@ -1709,6 +1712,8 @@ void tracing_reset_all_online_cpus(void)
 	}
 }
 
+static int *tgid_map;
+
 #define SAVED_CMDLINES_DEFAULT 128
 #define NO_CMDLINE_MAP UINT_MAX
 static arch_spinlock_t trace_cmdline_lock = __ARCH_SPIN_LOCK_UNLOCKED;
@@ -1722,7 +1727,7 @@ struct saved_cmdlines_buffer {
 static struct saved_cmdlines_buffer *savedcmd;
 
 /* temporary disable recording */
-static atomic_t trace_record_cmdline_disabled __read_mostly;
+static atomic_t trace_record_taskinfo_disabled __read_mostly;
 
 static inline char *get_saved_cmdlines(int idx)
 {
@@ -1910,13 +1915,15 @@ static void tracing_stop_tr(struct trace_array *tr)
 	raw_spin_unlock_irqrestore(&tr->start_lock, flags);
 }
 
-void trace_stop_cmdline_recording(void);
-
 static int trace_save_cmdline(struct task_struct *tsk)
 {
 	unsigned pid, idx;
 
-	if (!tsk->pid || unlikely(tsk->pid > PID_MAX_DEFAULT))
+	/* treat recording of idle task as a success */
+	if (!tsk->pid)
+		return 1;
+
+	if (unlikely(tsk->pid > PID_MAX_DEFAULT))
 		return 0;
 
 	/*
@@ -1992,16 +1999,107 @@ void trace_find_cmdline(int pid, char comm[])
 	preempt_enable();
 }
 
-void tracing_record_cmdline(struct task_struct *tsk)
+int trace_find_tgid(int pid)
+{
+	if (unlikely(!tgid_map || !pid || pid > PID_MAX_DEFAULT))
+		return 0;
+
+	return tgid_map[pid];
+}
+
+static int trace_save_tgid(struct task_struct *tsk)
+{
+	/* treat recording of idle task as a success */
+	if (!tsk->pid)
+		return 1;
+
+	if (unlikely(!tgid_map || tsk->pid > PID_MAX_DEFAULT))
+		return 0;
+
+	tgid_map[tsk->pid] = tsk->tgid;
+	return 1;
+}
+
+static bool tracing_record_taskinfo_skip(int flags)
+{
+	if (unlikely(!(flags & (TRACE_RECORD_CMDLINE | TRACE_RECORD_TGID))))
+		return true;
+	if (atomic_read(&trace_record_taskinfo_disabled) || !tracing_is_on())
+		return true;
+	if (!__this_cpu_read(trace_taskinfo_save))
+		return true;
+	return false;
+}
+
+/**
+ * tracing_record_taskinfo - record the task info of a task
+ *
+ * @task  - task to record
+ * @flags - TRACE_RECORD_CMDLINE for recording comm
+ *        - TRACE_RECORD_TGID for recording tgid
+ */
+void tracing_record_taskinfo(struct task_struct *task, int flags)
+{
+	bool done;
+
+	if (tracing_record_taskinfo_skip(flags))
+		return;
+
+	/*
+	 * Record as much task information as possible. If some fail, continue
+	 * to try to record the others.
+	 */
+	done = !(flags & TRACE_RECORD_CMDLINE) || trace_save_cmdline(task);
+	done &= !(flags & TRACE_RECORD_TGID) || trace_save_tgid(task);
+
+	/* If recording any information failed, retry again soon. */
+	if (!done)
+		return;
+
+	__this_cpu_write(trace_taskinfo_save, false);
+}
+
+/**
+ * tracing_record_taskinfo_sched_switch - record task info for sched_switch
+ *
+ * @prev - previous task during sched_switch
+ * @next - next task during sched_switch
+ * @flags - TRACE_RECORD_CMDLINE for recording comm
+ *          TRACE_RECORD_TGID for recording tgid
+ */
+void tracing_record_taskinfo_sched_switch(struct task_struct *prev,
+					  struct task_struct *next, int flags)
 {
-	if (atomic_read(&trace_record_cmdline_disabled) || !tracing_is_on())
+	bool done;
+
+	if (tracing_record_taskinfo_skip(flags))
 		return;
 
-	if (!__this_cpu_read(trace_cmdline_save))
+	/*
+	 * Record as much task information as possible. If some fail, continue
+	 * to try to record the others.
+	 */
+	done  = !(flags & TRACE_RECORD_CMDLINE) || trace_save_cmdline(prev);
+	done &= !(flags & TRACE_RECORD_CMDLINE) || trace_save_cmdline(next);
+	done &= !(flags & TRACE_RECORD_TGID) || trace_save_tgid(prev);
+	done &= !(flags & TRACE_RECORD_TGID) || trace_save_tgid(next);
+
+	/* If recording any information failed, retry again soon. */
+	if (!done)
 		return;
 
-	if (trace_save_cmdline(tsk))
-		__this_cpu_write(trace_cmdline_save, false);
+	__this_cpu_write(trace_taskinfo_save, false);
+}
+
+/* Helpers to record a specific task information */
+void tracing_record_cmdline(struct task_struct *task)
+{
+	tracing_record_taskinfo(task, TRACE_RECORD_CMDLINE);
+}
+
+void tracing_record_tgid(struct task_struct *task)
+{
+	tracing_record_taskinfo(task, TRACE_RECORD_TGID);
 }
 
 /*
@@ -2704,11 +2802,17 @@ static char *get_trace_buf(void)
 	if (!buffer || buffer->nesting >= 4)
 		return NULL;
 
-	return &buffer->buffer[buffer->nesting++][0];
+	buffer->nesting++;
+
+	/* Interrupts must see nesting incremented before we use the buffer */
+	barrier();
+	return &buffer->buffer[buffer->nesting][0];
 }
 
 static void put_trace_buf(void)
 {
+	/* Don't let the decrement of nesting leak before this */
+	barrier();
 	this_cpu_dec(trace_percpu_buffer->nesting);
 }
 
@@ -3146,7 +3250,7 @@ static void *s_start(struct seq_file *m, loff_t *pos)
 #endif
 
 	if (!iter->snapshot)
-		atomic_inc(&trace_record_cmdline_disabled);
+		atomic_inc(&trace_record_taskinfo_disabled);
 
 	if (*pos != iter->pos) {
 		iter->ent = NULL;
@@ -3191,7 +3295,7 @@ static void s_stop(struct seq_file *m, void *p)
 #endif
 
 	if (!iter->snapshot)
-		atomic_dec(&trace_record_cmdline_disabled);
+		atomic_dec(&trace_record_taskinfo_disabled);
 
 	trace_access_unlock(iter->cpu_file);
 	trace_event_read_unlock();
@@ -3248,23 +3352,38 @@ static void print_event_info(struct trace_buffer *buf, struct seq_file *m)
 	seq_puts(m, "#\n");
 }
 
-static void print_func_help_header(struct trace_buffer *buf, struct seq_file *m)
+static void print_func_help_header(struct trace_buffer *buf, struct seq_file *m,
+				   unsigned int flags)
 {
+	bool tgid = flags & TRACE_ITER_RECORD_TGID;
+
 	print_event_info(buf, m);
-	seq_puts(m, "#           TASK-PID   CPU#      TIMESTAMP  FUNCTION\n"
-		    "#              | |       |          |         |\n");
+
+	seq_printf(m, "#           TASK-PID   CPU#   %s  TIMESTAMP  FUNCTION\n", tgid ? "TGID     " : "");
+	seq_printf(m, "#              | |       |    %s     |         |\n",	 tgid ? "  |      " : "");
 }
 
-static void print_func_help_header_irq(struct trace_buffer *buf, struct seq_file *m)
+static void print_func_help_header_irq(struct trace_buffer *buf, struct seq_file *m,
+				       unsigned int flags)
 {
-	print_event_info(buf, m);
-	seq_puts(m, "#                              _-----=> irqs-off\n"
-		    "#                             / _----=> need-resched\n"
-		    "#                            | / _---=> hardirq/softirq\n"
-		    "#                            || / _--=> preempt-depth\n"
-		    "#                            ||| /     delay\n"
-		    "#           TASK-PID   CPU#  ||||    TIMESTAMP  FUNCTION\n"
-		    "#              | |       |   ||||       |         |\n");
+	bool tgid = flags & TRACE_ITER_RECORD_TGID;
+	const char tgid_space[] = "          ";
+	const char space[] = "  ";
+
+	seq_printf(m, "#                          %s  _-----=> irqs-off\n",
+		   tgid ? tgid_space : space);
+	seq_printf(m, "#                          %s / _----=> need-resched\n",
+		   tgid ? tgid_space : space);
+	seq_printf(m, "#                          %s| / _---=> hardirq/softirq\n",
+		   tgid ? tgid_space : space);
+	seq_printf(m, "#                          %s|| / _--=> preempt-depth\n",
+		   tgid ? tgid_space : space);
+	seq_printf(m, "#                          %s||| /     delay\n",
+		   tgid ? tgid_space : space);
+	seq_printf(m, "#           TASK-PID   CPU#%s||||    TIMESTAMP  FUNCTION\n",
+		   tgid ? "   TGID   " : space);
+	seq_printf(m, "#              | |       | %s||||       |         |\n",
+		   tgid ? "     |    " : space);
 }
 
 void
@@ -3580,9 +3699,11 @@ void trace_default_header(struct seq_file *m)
 	} else {
 		if (!(trace_flags & TRACE_ITER_VERBOSE)) {
 			if (trace_flags & TRACE_ITER_IRQ_INFO)
-				print_func_help_header_irq(iter->trace_buffer, m);
+				print_func_help_header_irq(iter->trace_buffer,
+							   m, trace_flags);
 			else
-				print_func_help_header(iter->trace_buffer, m);
+				print_func_help_header(iter->trace_buffer, m,
+						       trace_flags);
 		}
 	}
 }
@@ -3899,11 +4020,17 @@ static int tracing_open(struct inode *inode, struct file *file)
 	/* If this file was open for write, then erase contents */
 	if ((file->f_mode & FMODE_WRITE) && (file->f_flags & O_TRUNC)) {
 		int cpu = tracing_get_cpu(inode);
+		struct trace_buffer *trace_buf = &tr->trace_buffer;
+
+#ifdef CONFIG_TRACER_MAX_TRACE
+		if (tr->current_trace->print_max)
+			trace_buf = &tr->max_buffer;
+#endif
 
 		if (cpu == RING_BUFFER_ALL_CPUS)
-			tracing_reset_online_cpus(&tr->trace_buffer);
+			tracing_reset_online_cpus(trace_buf);
 		else
-			tracing_reset(&tr->trace_buffer, cpu);
+			tracing_reset(trace_buf, cpu);
 	}
 
 	if (file->f_mode & FMODE_READ) {
@@ -4238,6 +4365,18 @@ int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled)
 	if (mask == TRACE_ITER_RECORD_CMD)
 		trace_event_enable_cmd_record(enabled);
 
+	if (mask == TRACE_ITER_RECORD_TGID) {
+		if (!tgid_map)
+			tgid_map = kzalloc((PID_MAX_DEFAULT + 1) * sizeof(*tgid_map),
+					   GFP_KERNEL);
+		if (!tgid_map) {
+			tr->trace_flags &= ~TRACE_ITER_RECORD_TGID;
+			return -ENOMEM;
+		}
+
+		trace_event_enable_tgid_record(enabled);
+	}
+
 	if (mask == TRACE_ITER_EVENT_FORK)
 		trace_event_follow_fork(tr, enabled);
 
@@ -4473,7 +4612,8 @@ static const char readme_msg[] =
 #endif
 #if defined(CONFIG_KPROBE_EVENTS) || defined(CONFIG_UPROBE_EVENTS)
 	"\t  accepts: event-definitions (one definition per line)\n"
-	"\t   Format: p|r[:[<group>/]<event>] <place> [<args>]\n"
+	"\t   Format: p[:[<group>/]<event>] <place> [<args>]\n"
+	"\t           r[maxactive][:[<group>/]<event>] <place> [<args>]\n"
 	"\t           -:[<group>/]<event>\n"
 #ifdef CONFIG_KPROBE_EVENTS
 	"\t    place: [<module>:]<symbol>[+<offset>]|<memaddr>\n"
@@ -4597,6 +4737,76 @@ static const struct file_operations tracing_readme_fops = {
 	.llseek		= generic_file_llseek,
 };
 
+static void *saved_tgids_next(struct seq_file *m, void *v, loff_t *pos)
+{
+	int *ptr = v;
+
+	if (*pos || m->count)
+		ptr++;
+
+	(*pos)++;
+
+	for (; ptr <= &tgid_map[PID_MAX_DEFAULT]; ptr++) {
+		if (trace_find_tgid(*ptr))
+			return ptr;
+	}
+
+	return NULL;
+}
+
+static void *saved_tgids_start(struct seq_file *m, loff_t *pos)
+{
+	void *v;
+	loff_t l = 0;
+
+	if (!tgid_map)
+		return NULL;
+
+	v = &tgid_map[0];
+	while (l <= *pos) {
+		v = saved_tgids_next(m, v, &l);
+		if (!v)
+			return NULL;
+	}
+
+	return v;
+}
+
+static void saved_tgids_stop(struct seq_file *m, void *v)
+{
+}
+
+static int saved_tgids_show(struct seq_file *m, void *v)
+{
+	int pid = (int *)v - tgid_map;
+
+	seq_printf(m, "%d %d\n", pid, trace_find_tgid(pid));
+	return 0;
+}
+
+static const struct seq_operations tracing_saved_tgids_seq_ops = {
+	.start		= saved_tgids_start,
+	.stop		= saved_tgids_stop,
+	.next		= saved_tgids_next,
+	.show		= saved_tgids_show,
+};
+
+static int tracing_saved_tgids_open(struct inode *inode, struct file *filp)
+{
+	if (tracing_disabled)
+		return -ENODEV;
+
+	return seq_open(filp, &tracing_saved_tgids_seq_ops);
+}
+
+
+static const struct file_operations tracing_saved_tgids_fops = {
+	.open		= tracing_saved_tgids_open,
+	.read		= seq_read,
+	.llseek		= seq_lseek,
+	.release	= seq_release,
+};
+
 static void *saved_cmdlines_next(struct seq_file *m, void *v, loff_t *pos)
 {
 	unsigned int *ptr = v;
@@ -4746,11 +4956,11 @@ static const struct file_operations tracing_saved_cmdlines_size_fops = {
 	.write		= tracing_saved_cmdlines_size_write,
 };
 
-#ifdef CONFIG_TRACE_ENUM_MAP_FILE
-static union trace_enum_map_item *
-update_enum_map(union trace_enum_map_item *ptr)
+#ifdef CONFIG_TRACE_EVAL_MAP_FILE
+static union trace_eval_map_item *
+update_eval_map(union trace_eval_map_item *ptr)
 {
-	if (!ptr->map.enum_string) {
+	if (!ptr->map.eval_string) {
 		if (ptr->tail.next) {
 			ptr = ptr->tail.next;
 			/* Set ptr to the next real item (skip head) */
@@ -4761,15 +4971,15 @@ update_enum_map(union trace_enum_map_item *ptr)
 	return ptr;
 }
 
-static void *enum_map_next(struct seq_file *m, void *v, loff_t *pos)
+static void *eval_map_next(struct seq_file *m, void *v, loff_t *pos)
 {
-	union trace_enum_map_item *ptr = v;
+	union trace_eval_map_item *ptr = v;
 
 	/*
 	 * Paranoid! If ptr points to end, we don't want to increment past it.
 	 * This really should never happen.
 	 */
-	ptr = update_enum_map(ptr);
+	ptr = update_eval_map(ptr);
 	if (WARN_ON_ONCE(!ptr))
 		return NULL;
 
@@ -4777,104 +4987,104 @@ static void *enum_map_next(struct seq_file *m, void *v, loff_t *pos)
 
 	(*pos)++;
 
-	ptr = update_enum_map(ptr);
+	ptr = update_eval_map(ptr);
 
 	return ptr;
 }
 
-static void *enum_map_start(struct seq_file *m, loff_t *pos)
+static void *eval_map_start(struct seq_file *m, loff_t *pos)
 {
-	union trace_enum_map_item *v;
+	union trace_eval_map_item *v;
 	loff_t l = 0;
 
-	mutex_lock(&trace_enum_mutex);
+	mutex_lock(&trace_eval_mutex);
 
-	v = trace_enum_maps;
+	v = trace_eval_maps;
 	if (v)
 		v++;
 
 	while (v && l < *pos) {
-		v = enum_map_next(m, v, &l);
+		v = eval_map_next(m, v, &l);
 	}
 
 	return v;
 }
 
-static void enum_map_stop(struct seq_file *m, void *v)
+static void eval_map_stop(struct seq_file *m, void *v)
 {
-	mutex_unlock(&trace_enum_mutex);
+	mutex_unlock(&trace_eval_mutex);
 }
 
-static int enum_map_show(struct seq_file *m, void *v)
+static int eval_map_show(struct seq_file *m, void *v)
 {
-	union trace_enum_map_item *ptr = v;
+	union trace_eval_map_item *ptr = v;
 
 	seq_printf(m, "%s %ld (%s)\n",
-		   ptr->map.enum_string, ptr->map.enum_value,
+		   ptr->map.eval_string, ptr->map.eval_value,
 		   ptr->map.system);
 
 	return 0;
 }
 
-static const struct seq_operations tracing_enum_map_seq_ops = {
-	.start		= enum_map_start,
-	.next		= enum_map_next,
-	.stop		= enum_map_stop,
-	.show		= enum_map_show,
+static const struct seq_operations tracing_eval_map_seq_ops = {
+	.start		= eval_map_start,
+	.next		= eval_map_next,
+	.stop		= eval_map_stop,
+	.show		= eval_map_show,
 };
 
-static int tracing_enum_map_open(struct inode *inode, struct file *filp)
+static int tracing_eval_map_open(struct inode *inode, struct file *filp)
 {
 	if (tracing_disabled)
 		return -ENODEV;
 
-	return seq_open(filp, &tracing_enum_map_seq_ops);
+	return seq_open(filp, &tracing_eval_map_seq_ops);
 }
 
-static const struct file_operations tracing_enum_map_fops = {
-	.open		= tracing_enum_map_open,
+static const struct file_operations tracing_eval_map_fops = {
+	.open		= tracing_eval_map_open,
 	.read		= seq_read,
 	.llseek		= seq_lseek,
 	.release	= seq_release,
 };
 
-static inline union trace_enum_map_item *
-trace_enum_jmp_to_tail(union trace_enum_map_item *ptr)
+static inline union trace_eval_map_item *
+trace_eval_jmp_to_tail(union trace_eval_map_item *ptr)
 {
 	/* Return tail of array given the head */
 	return ptr + ptr->head.length + 1;
 }
 
 static void
-trace_insert_enum_map_file(struct module *mod, struct trace_enum_map **start,
+trace_insert_eval_map_file(struct module *mod, struct trace_eval_map **start,
 			   int len)
 {
-	struct trace_enum_map **stop;
-	struct trace_enum_map **map;
-	union trace_enum_map_item *map_array;
-	union trace_enum_map_item *ptr;
+	struct trace_eval_map **stop;
+	struct trace_eval_map **map;
+	union trace_eval_map_item *map_array;
+	union trace_eval_map_item *ptr;
 
 	stop = start + len;
 
 	/*
-	 * The trace_enum_maps contains the map plus a head and tail item,
+	 * The trace_eval_maps contains the map plus a head and tail item,
 	 * where the head holds the module and length of array, and the
 	 * tail holds a pointer to the next list.
 	 */
 	map_array = kmalloc(sizeof(*map_array) * (len + 2), GFP_KERNEL);
 	if (!map_array) {
-		pr_warn("Unable to allocate trace enum mapping\n");
+		pr_warn("Unable to allocate trace eval mapping\n");
 		return;
 	}
 
-	mutex_lock(&trace_enum_mutex);
+	mutex_lock(&trace_eval_mutex);
 
-	if (!trace_enum_maps)
-		trace_enum_maps = map_array;
+	if (!trace_eval_maps)
+		trace_eval_maps = map_array;
 	else {
-		ptr = trace_enum_maps;
+		ptr = trace_eval_maps;
 		for (;;) {
-			ptr = trace_enum_jmp_to_tail(ptr);
+			ptr = trace_eval_jmp_to_tail(ptr);
 			if (!ptr->tail.next)
 				break;
 			ptr = ptr->tail.next;
@@ -4892,34 +5102,34 @@ trace_insert_enum_map_file(struct module *mod, struct trace_enum_map **start,
 	}
 	memset(map_array, 0, sizeof(*map_array));
 
-	mutex_unlock(&trace_enum_mutex);
+	mutex_unlock(&trace_eval_mutex);
 }
 
-static void trace_create_enum_file(struct dentry *d_tracer)
+static void trace_create_eval_file(struct dentry *d_tracer)
 {
-	trace_create_file("enum_map", 0444, d_tracer,
-			  NULL, &tracing_enum_map_fops);
+	trace_create_file("eval_map", 0444, d_tracer,
+			  NULL, &tracing_eval_map_fops);
 }
 
-#else /* CONFIG_TRACE_ENUM_MAP_FILE */
-static inline void trace_create_enum_file(struct dentry *d_tracer) { }
-static inline void trace_insert_enum_map_file(struct module *mod,
-			      struct trace_enum_map **start, int len) { }
-#endif /* !CONFIG_TRACE_ENUM_MAP_FILE */
+#else /* CONFIG_TRACE_EVAL_MAP_FILE */
+static inline void trace_create_eval_file(struct dentry *d_tracer) { }
+static inline void trace_insert_eval_map_file(struct module *mod,
+			      struct trace_eval_map **start, int len) { }
+#endif /* !CONFIG_TRACE_EVAL_MAP_FILE */
 
-static void trace_insert_enum_map(struct module *mod,
-				  struct trace_enum_map **start, int len)
+static void trace_insert_eval_map(struct module *mod,
+				  struct trace_eval_map **start, int len)
 {
-	struct trace_enum_map **map;
+	struct trace_eval_map **map;
 
 	if (len <= 0)
 		return;
 
 	map = start;
 
-	trace_event_enum_update(map, len);
+	trace_event_eval_update(map, len);
 
-	trace_insert_enum_map_file(mod, start, len);
+	trace_insert_eval_map_file(mod, start, len);
 }
 
 static ssize_t
@@ -5154,6 +5364,13 @@ static int tracing_set_tracer(struct trace_array *tr, const char *buf)
 	if (t == tr->current_trace)
 		goto out;
 
+	/* Some tracers won't work on kernel command line */
+	if (system_state < SYSTEM_RUNNING && t->noboot) {
+		pr_warn("Tracer '%s' is not allowed on command line, ignored\n",
+			t->name);
+		goto out;
+	}
+
 	/* Some tracers are only allowed for the top level buffer */
 	if (!trace_ok_for_array(t, tr)) {
 		ret = -EINVAL;
@@ -5463,7 +5680,7 @@ static int tracing_wait_pipe(struct file *filp)
 		 *
 		 * iter->pos will be 0 if we haven't read anything.
 		 */
-		if (!tracing_is_on() && iter->pos)
+		if (!tracer_tracing_is_on(iter->tr) && iter->pos)
 			break;
 
 		mutex_unlock(&iter->mutex);
@@ -6025,7 +6242,7 @@ static int tracing_set_clock(struct trace_array *tr, const char *clockstr)
 	tracing_reset_online_cpus(&tr->trace_buffer);
 
 #ifdef CONFIG_TRACER_MAX_TRACE
-	if (tr->flags & TRACE_ARRAY_FL_GLOBAL && tr->max_buffer.buffer)
+	if (tr->max_buffer.buffer)
 		ring_buffer_set_clock(tr->max_buffer.buffer, trace_clocks[i].func);
 	tracing_reset_online_cpus(&tr->max_buffer);
 #endif
@@ -6403,7 +6620,7 @@ tracing_buffers_read(struct file *filp, char __user *ubuf,
 {
 	struct ftrace_buffer_info *info = filp->private_data;
 	struct trace_iterator *iter = &info->iter;
-	ssize_t ret;
+	ssize_t ret = 0;
 	ssize_t size;
 
 	if (!count)
@@ -6417,10 +6634,15 @@ tracing_buffers_read(struct file *filp, char __user *ubuf,
 	if (!info->spare) {
 		info->spare = ring_buffer_alloc_read_page(iter->trace_buffer->buffer,
 							  iter->cpu_file);
-		info->spare_cpu = iter->cpu_file;
+		if (IS_ERR(info->spare)) {
+			ret = PTR_ERR(info->spare);
+			info->spare = NULL;
+		} else {
+			info->spare_cpu = iter->cpu_file;
+		}
 	}
 	if (!info->spare)
-		return -ENOMEM;
+		return ret;
 
 	/* Do we have previous read data to read? */
 	if (info->read < PAGE_SIZE)
@@ -6595,8 +6817,9 @@ tracing_buffers_splice_read(struct file *file, loff_t *ppos,
 		ref->ref = 1;
 		ref->buffer = iter->trace_buffer->buffer;
 		ref->page = ring_buffer_alloc_read_page(ref->buffer, iter->cpu_file);
-		if (!ref->page) {
-			ret = -ENOMEM;
+		if (IS_ERR(ref->page)) {
+			ret = PTR_ERR(ref->page);
+			ref->page = NULL;
 			kfree(ref);
 			break;
 		}
@@ -6739,33 +6962,18 @@ static const struct file_operations tracing_stats_fops = {
 
 #ifdef CONFIG_DYNAMIC_FTRACE
 
-int __weak ftrace_arch_read_dyn_info(char *buf, int size)
-{
-	return 0;
-}
-
 static ssize_t
 tracing_read_dyn_info(struct file *filp, char __user *ubuf,
 		  size_t cnt, loff_t *ppos)
 {
-	static char ftrace_dyn_info_buffer[1024];
-	static DEFINE_MUTEX(dyn_info_mutex);
 	unsigned long *p = filp->private_data;
-	char *buf = ftrace_dyn_info_buffer;
-	int size = ARRAY_SIZE(ftrace_dyn_info_buffer);
+	char buf[64]; /* Not too big for a shallow stack */
 	int r;
 
-	mutex_lock(&dyn_info_mutex);
-	r = sprintf(buf, "%ld ", *p);
-
-	r += ftrace_arch_read_dyn_info(buf+r, (size-1)-r);
+	r = scnprintf(buf, 63, "%ld", *p);
 	buf[r++] = '\n';
 
-	r = simple_read_from_buffer(ubuf, cnt, ppos, buf, r);
-
-	mutex_unlock(&dyn_info_mutex);
-
-	return r;
+	return simple_read_from_buffer(ubuf, cnt, ppos, buf, r);
 }
 
 static const struct file_operations tracing_dyn_info_fops = {
@@ -7594,6 +7802,7 @@ static int instance_rmdir(const char *name)
 	}
 	kfree(tr->topts);
 
+	free_cpumask_var(tr->tracing_cpumask);
 	kfree(tr->name);
 	kfree(tr);
 
@@ -7737,21 +7946,21 @@ struct dentry *tracing_init_dentry(void)
 	return NULL;
 }
 
-extern struct trace_enum_map *__start_ftrace_enum_maps[];
-extern struct trace_enum_map *__stop_ftrace_enum_maps[];
+extern struct trace_eval_map *__start_ftrace_eval_maps[];
+extern struct trace_eval_map *__stop_ftrace_eval_maps[];
 
-static void __init trace_enum_init(void)
+static void __init trace_eval_init(void)
 {
 	int len;
 
-	len = __stop_ftrace_enum_maps - __start_ftrace_enum_maps;
-	trace_insert_enum_map(NULL, __start_ftrace_enum_maps, len);
+	len = __stop_ftrace_eval_maps - __start_ftrace_eval_maps;
+	trace_insert_eval_map(NULL, __start_ftrace_eval_maps, len);
 }
 
 #ifdef CONFIG_MODULES
-static void trace_module_add_enums(struct module *mod)
+static void trace_module_add_evals(struct module *mod)
 {
-	if (!mod->num_trace_enums)
+	if (!mod->num_trace_evals)
 		return;
 
 	/*
@@ -7761,40 +7970,40 @@ static void trace_module_add_enums(struct module *mod)
 	if (trace_module_has_bad_taint(mod))
 		return;
 
-	trace_insert_enum_map(mod, mod->trace_enums, mod->num_trace_enums);
+	trace_insert_eval_map(mod, mod->trace_evals, mod->num_trace_evals);
 }
 
-#ifdef CONFIG_TRACE_ENUM_MAP_FILE
-static void trace_module_remove_enums(struct module *mod)
+#ifdef CONFIG_TRACE_EVAL_MAP_FILE
+static void trace_module_remove_evals(struct module *mod)
 {
-	union trace_enum_map_item *map;
-	union trace_enum_map_item **last = &trace_enum_maps;
+	union trace_eval_map_item *map;
+	union trace_eval_map_item **last = &trace_eval_maps;
 
-	if (!mod->num_trace_enums)
+	if (!mod->num_trace_evals)
 		return;
 
-	mutex_lock(&trace_enum_mutex);
+	mutex_lock(&trace_eval_mutex);
 
-	map = trace_enum_maps;
+	map = trace_eval_maps;
 
 	while (map) {
 		if (map->head.mod == mod)
 			break;
-		map = trace_enum_jmp_to_tail(map);
+		map = trace_eval_jmp_to_tail(map);
 		last = &map->tail.next;
 		map = map->tail.next;
 	}
 	if (!map)
 		goto out;
 
-	*last = trace_enum_jmp_to_tail(map)->tail.next;
+	*last = trace_eval_jmp_to_tail(map)->tail.next;
 	kfree(map);
  out:
-	mutex_unlock(&trace_enum_mutex);
+	mutex_unlock(&trace_eval_mutex);
 }
 #else
-static inline void trace_module_remove_enums(struct module *mod) { }
-#endif /* CONFIG_TRACE_ENUM_MAP_FILE */
+static inline void trace_module_remove_evals(struct module *mod) { }
+#endif /* CONFIG_TRACE_EVAL_MAP_FILE */
 
 static int trace_module_notify(struct notifier_block *self,
 			       unsigned long val, void *data)
@@ -7803,10 +8012,10 @@ static int trace_module_notify(struct notifier_block *self,
 
 	switch (val) {
 	case MODULE_STATE_COMING:
-		trace_module_add_enums(mod);
+		trace_module_add_evals(mod);
 		break;
 	case MODULE_STATE_GOING:
-		trace_module_remove_enums(mod);
+		trace_module_remove_evals(mod);
 		break;
 	}
 
@@ -7844,9 +8053,12 @@ static __init int tracer_init_tracefs(void)
 	trace_create_file("saved_cmdlines_size", 0644, d_tracer,
 			  NULL, &tracing_saved_cmdlines_size_fops);
 
-	trace_enum_init();
+	trace_create_file("saved_tgids", 0444, d_tracer,
+			NULL, &tracing_saved_tgids_fops);
 
-	trace_create_enum_file(d_tracer);
+	trace_eval_init();
+
+	trace_create_eval_file(d_tracer);
 
 #ifdef CONFIG_MODULES
 	register_module_notifier(&trace_module_nb);
@@ -8109,6 +8321,7 @@ __init static int tracer_alloc_buffers(void)
 	if (ret < 0)
 		goto out_free_cpumask;
 	/* Used for event triggers */
+	ret = -ENOMEM;
 	temp_buffer = ring_buffer_alloc(PAGE_SIZE, RB_FL_OVERWRITE);
 	if (!temp_buffer)
 		goto out_rm_hp_state;
@@ -8223,4 +8436,4 @@ __init static int clear_boot_tracer(void)
 }
 
 fs_initcall(tracer_init_tracefs);
-late_initcall(clear_boot_tracer);
+late_initcall_sync(clear_boot_tracer);