16 files changed, 185 insertions, 147 deletions

diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig
index 1551f47e7669..019f380fd764 100644
--- a/kernel/trace/Kconfig
+++ b/kernel/trace/Kconfig
@@ -226,13 +226,13 @@ config BOOT_TRACER
           the timings of the initcalls and traces key events and the identity
           of tasks that can cause boot delays, such as context-switches.
 
-          Its aim is to be parsed by the /scripts/bootgraph.pl tool to
+          Its aim is to be parsed by the scripts/bootgraph.pl tool to
           produce pretty graphics about boot inefficiencies, giving a visual
           representation of the delays during initcalls - but the raw
           /debug/tracing/trace text output is readable too.
 
-          You must pass in ftrace=initcall to the kernel command line
-          to enable this on bootup.
+          You must pass in initcall_debug and ftrace=initcall to the kernel
+          command line to enable this on bootup.
 
 config TRACE_BRANCH_PROFILING
         bool
diff --git a/kernel/trace/blktrace.c b/kernel/trace/blktrace.c
index 39af8af6fc30..7a34cb563fec 100644
--- a/kernel/trace/blktrace.c
+++ b/kernel/trace/blktrace.c
@@ -22,6 +22,7 @@
 #include <linux/init.h>
 #include <linux/mutex.h>
 #include <linux/debugfs.h>
+#include <linux/smp_lock.h>
 #include <linux/time.h>
 #include <linux/uaccess.h>
 
@@ -266,8 +267,8 @@ static void blk_trace_free(struct blk_trace *bt)
 {
         debugfs_remove(bt->msg_file);
         debugfs_remove(bt->dropped_file);
-        debugfs_remove(bt->dir);
         relay_close(bt->rchan);
+        debugfs_remove(bt->dir);
         free_percpu(bt->sequence);
         free_percpu(bt->msg_data);
         kfree(bt);
@@ -377,18 +378,8 @@ static int blk_subbuf_start_callback(struct rchan_buf *buf, void *subbuf,
 
 static int blk_remove_buf_file_callback(struct dentry *dentry)
 {
-        struct dentry *parent = dentry->d_parent;
         debugfs_remove(dentry);
 
-        /*
-        * this will fail for all but the last file, but that is ok. what we
-        * care about is the top level buts->name directory going away, when
-        * the last trace file is gone. Then we don't have to rmdir() that
-        * manually on trace stop, so it nicely solves the issue with
-        * force killing of running traces.
-        */
-
-        debugfs_remove(parent);
         return 0;
 }
 
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 3718d55fb4c3..1e1d23c26308 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -291,7 +291,9 @@ function_stat_next(void *v, int idx)
         pg = (struct ftrace_profile_page *)((unsigned long)rec & PAGE_MASK);
 
  again:
-        rec++;
+        if (idx != 0)
+                rec++;
+
         if ((void *)rec >= (void *)&pg->records[pg->index]) {
                 pg = pg->next;
                 if (!pg)
@@ -766,7 +768,7 @@ static struct tracer_stat function_stats __initdata = {
         .stat_show      = function_stat_show
 };
 
-static void ftrace_profile_debugfs(struct dentry *d_tracer)
+static __init void ftrace_profile_debugfs(struct dentry *d_tracer)
 {
         struct ftrace_profile_stat *stat;
         struct dentry *entry;
@@ -784,7 +786,6 @@ static void ftrace_profile_debugfs(struct dentry *d_tracer)
                          * The files created are permanent, if something happens
                          * we still do not free memory.
                          */
-                        kfree(stat);
                         WARN(1,
                              "Could not allocate stat file for cpu %d\n",
                              cpu);
@@ -811,7 +812,7 @@ static void ftrace_profile_debugfs(struct dentry *d_tracer)
 }
 
 #else /* CONFIG_FUNCTION_PROFILER */
-static void ftrace_profile_debugfs(struct dentry *d_tracer)
+static __init void ftrace_profile_debugfs(struct dentry *d_tracer)
 {
 }
 #endif /* CONFIG_FUNCTION_PROFILER */
@@ -1417,10 +1418,20 @@ static void *t_hash_start(struct seq_file *m, loff_t *pos)
 {
         struct ftrace_iterator *iter = m->private;
         void *p = NULL;
+        loff_t l;
+
+        if (!(iter->flags & FTRACE_ITER_HASH))
+                *pos = 0;
 
         iter->flags |= FTRACE_ITER_HASH;
 
-        return t_hash_next(m, p, pos);
+        iter->hidx = 0;
+        for (l = 0; l <= *pos; ) {
+                p = t_hash_next(m, p, &l);
+                if (!p)
+                        break;
+        }
+        return p;
 }
 
 static int t_hash_show(struct seq_file *m, void *v)
@@ -1467,8 +1478,6 @@ t_next(struct seq_file *m, void *v, loff_t *pos)
                         iter->pg = iter->pg->next;
                         iter->idx = 0;
                         goto retry;
-                } else {
-                        iter->idx = -1;
                 }
         } else {
                 rec = &iter->pg->records[iter->idx++];
@@ -1497,6 +1506,7 @@ static void *t_start(struct seq_file *m, loff_t *pos)
 {
         struct ftrace_iterator *iter = m->private;
         void *p = NULL;
+        loff_t l;
 
         mutex_lock(&ftrace_lock);
         /*
@@ -1508,23 +1518,21 @@ static void *t_start(struct seq_file *m, loff_t *pos)
                 if (*pos > 0)
                         return t_hash_start(m, pos);
                 iter->flags |= FTRACE_ITER_PRINTALL;
-                (*pos)++;
                 return iter;
         }
 
         if (iter->flags & FTRACE_ITER_HASH)
                 return t_hash_start(m, pos);
 
-        if (*pos > 0) {
-                if (iter->idx < 0)
-                        return p;
-                (*pos)--;
-                iter->idx--;
+        iter->pg = ftrace_pages_start;
+        iter->idx = 0;
+        for (l = 0; l <= *pos; ) {
+                p = t_next(m, p, &l);
+                if (!p)
+                        break;
         }
 
-        p = t_next(m, p, pos);
-
-        if (!p)
+        if (!p && iter->flags & FTRACE_ITER_FILTER)
                 return t_hash_start(m, pos);
 
         return p;
@@ -1654,7 +1662,7 @@ ftrace_regex_open(struct inode *inode, struct file *file, int enable)
 
         mutex_lock(&ftrace_regex_lock);
         if ((file->f_mode & FMODE_WRITE) &&
-            !(file->f_flags & O_APPEND))
+            (file->f_flags & O_TRUNC))
                 ftrace_filter_reset(enable);
 
         if (file->f_mode & FMODE_READ) {
@@ -2500,32 +2508,31 @@ int ftrace_graph_count;
 unsigned long ftrace_graph_funcs[FTRACE_GRAPH_MAX_FUNCS] __read_mostly;
 
 static void *
-g_next(struct seq_file *m, void *v, loff_t *pos)
+__g_next(struct seq_file *m, loff_t *pos)
 {
         unsigned long *array = m->private;
-        int index = *pos;
-
-        (*pos)++;
 
-        if (index >= ftrace_graph_count)
+        if (*pos >= ftrace_graph_count)
                 return NULL;
+        return &array[*pos];
+}
 
-        return &array[index];
+static void *
+g_next(struct seq_file *m, void *v, loff_t *pos)
+{
+        (*pos)++;
+        return __g_next(m, pos);
 }
 
 static void *g_start(struct seq_file *m, loff_t *pos)
 {
-        void *p = NULL;
-
         mutex_lock(&graph_lock);
 
         /* Nothing, tell g_show to print all functions are enabled */
         if (!ftrace_graph_count && !*pos)
                 return (void *)1;
 
-        p = g_next(m, p, pos);
-
-        return p;
+        return __g_next(m, pos);
 }
 
 static void g_stop(struct seq_file *m, void *p)
@@ -2570,7 +2577,7 @@ ftrace_graph_open(struct inode *inode, struct file *file)
 
         mutex_lock(&graph_lock);
         if ((file->f_mode & FMODE_WRITE) &&
-            !(file->f_flags & O_APPEND)) {
+            (file->f_flags & O_TRUNC)) {
                 ftrace_graph_count = 0;
                 memset(ftrace_graph_funcs, 0, sizeof(ftrace_graph_funcs));
         }
@@ -2589,6 +2596,14 @@ ftrace_graph_open(struct inode *inode, struct file *file)
 }
 
 static int
+ftrace_graph_release(struct inode *inode, struct file *file)
+{
+        if (file->f_mode & FMODE_READ)
+                seq_release(inode, file);
+        return 0;
+}
+
+static int
 ftrace_set_func(unsigned long *array, int *idx, char *buffer)
 {
         struct dyn_ftrace *rec;
@@ -2717,9 +2732,10 @@ ftrace_graph_write(struct file *file, const char __user *ubuf,
 }
 
 static const struct file_operations ftrace_graph_fops = {
-        .open = ftrace_graph_open,
-        .read = seq_read,
-        .write = ftrace_graph_write,
+        .open           = ftrace_graph_open,
+        .read           = seq_read,
+        .write          = ftrace_graph_write,
+        .release        = ftrace_graph_release,
 };
 #endif /* CONFIG_FUNCTION_GRAPH_TRACER */
 
@@ -3152,10 +3168,10 @@ ftrace_enable_sysctl(struct ctl_table *table, int write,
 
         ret  = proc_dointvec(table, write, file, buffer, lenp, ppos);
 
-        if (ret || !write || (last_ftrace_enabled == ftrace_enabled))
+        if (ret || !write || (last_ftrace_enabled == !!ftrace_enabled))
                 goto out;
 
-        last_ftrace_enabled = ftrace_enabled;
+        last_ftrace_enabled = !!ftrace_enabled;
 
         if (ftrace_enabled) {
 
diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c
index 04dac2638258..a330513d96ce 100644
--- a/kernel/trace/ring_buffer.c
+++ b/kernel/trace/ring_buffer.c
@@ -735,6 +735,7 @@ ring_buffer_free(struct ring_buffer *buffer)
 
         put_online_cpus();
 
+        kfree(buffer->buffers);
         free_cpumask_var(buffer->cpumask);
 
         kfree(buffer);
@@ -1563,6 +1564,8 @@ rb_reserve_next_event(struct ring_buffer_per_cpu *cpu_buffer,
         return NULL;
 }
 
+#ifdef CONFIG_TRACING
+
 #define TRACE_RECURSIVE_DEPTH 16
 
 static int trace_recursive_lock(void)
@@ -1593,6 +1596,13 @@ static void trace_recursive_unlock(void)
         current->trace_recursion--;
 }
 
+#else
+
+#define trace_recursive_lock()          (0)
+#define trace_recursive_unlock()        do { } while (0)
+
+#endif
+
 static DEFINE_PER_CPU(int, rb_need_resched);
 
 /**
@@ -1776,7 +1786,7 @@ void ring_buffer_discard_commit(struct ring_buffer *buffer,
          */
         RB_WARN_ON(buffer, !local_read(&cpu_buffer->committing));
 
-        if (!rb_try_to_discard(cpu_buffer, event))
+        if (rb_try_to_discard(cpu_buffer, event))
                 goto out;
 
         /*
@@ -2374,7 +2384,6 @@ rb_buffer_peek(struct ring_buffer *buffer, int cpu, u64 *ts)
                  * the box. Return the padding, and we will release
                  * the current locks, and try again.
                  */
-                rb_advance_reader(cpu_buffer);
                 return event;
 
         case RINGBUF_TYPE_TIME_EXTEND:
@@ -2477,7 +2486,7 @@ static inline int rb_ok_to_lock(void)
          * buffer too. A one time deal is all you get from reading
          * the ring buffer from an NMI.
          */
-        if (likely(!in_nmi() && !oops_in_progress))
+        if (likely(!in_nmi()))
                 return 1;
 
         tracing_off_permanent();
@@ -2510,6 +2519,8 @@ ring_buffer_peek(struct ring_buffer *buffer, int cpu, u64 *ts)
         if (dolock)
                 spin_lock(&cpu_buffer->reader_lock);
         event = rb_buffer_peek(buffer, cpu, ts);
+        if (event && event->type_len == RINGBUF_TYPE_PADDING)
+                rb_advance_reader(cpu_buffer);
         if (dolock)
                 spin_unlock(&cpu_buffer->reader_lock);
         local_irq_restore(flags);
@@ -2581,12 +2592,9 @@ ring_buffer_consume(struct ring_buffer *buffer, int cpu, u64 *ts)
                 spin_lock(&cpu_buffer->reader_lock);
 
         event = rb_buffer_peek(buffer, cpu, ts);
-        if (!event)
-                goto out_unlock;
-
-        rb_advance_reader(cpu_buffer);
+        if (event)
+                rb_advance_reader(cpu_buffer);
 
- out_unlock:
         if (dolock)
                 spin_unlock(&cpu_buffer->reader_lock);
         local_irq_restore(flags);
@@ -3104,6 +3112,7 @@ int ring_buffer_read_page(struct ring_buffer *buffer,
 }
 EXPORT_SYMBOL_GPL(ring_buffer_read_page);
 
+#ifdef CONFIG_TRACING
 static ssize_t
 rb_simple_read(struct file *filp, char __user *ubuf,
                size_t cnt, loff_t *ppos)
@@ -3171,6 +3180,7 @@ static __init int rb_init_debugfs(void)
 }
 
 fs_initcall(rb_init_debugfs);
+#endif
 
 #ifdef CONFIG_HOTPLUG_CPU
 static int rb_cpu_notify(struct notifier_block *self,
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 076fa6f0ee48..c22b40f8f576 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -17,6 +17,7 @@
 #include <linux/writeback.h>
 #include <linux/kallsyms.h>
 #include <linux/seq_file.h>
+#include <linux/smp_lock.h>
 #include <linux/notifier.h>
 #include <linux/irqflags.h>
 #include <linux/debugfs.h>
@@ -284,13 +285,12 @@ void trace_wake_up(void)
 static int __init set_buf_size(char *str)
 {
         unsigned long buf_size;
-        int ret;
 
         if (!str)
                 return 0;
-        ret = strict_strtoul(str, 0, &buf_size);
+        buf_size = memparse(str, &str);
         /* nr_entries can not be zero */
-        if (ret < 0 || buf_size == 0)
+        if (buf_size == 0)
                 return 0;
         trace_buf_size = buf_size;
         return 1;
@@ -848,6 +848,7 @@ tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags,
                 ((pc & SOFTIRQ_MASK) ? TRACE_FLAG_SOFTIRQ : 0) |
                 (need_resched() ? TRACE_FLAG_NEED_RESCHED : 0);
 }
+EXPORT_SYMBOL_GPL(tracing_generic_entry_update);
 
 struct ring_buffer_event *trace_buffer_lock_reserve(struct trace_array *tr,
                                                     int type,
@@ -2031,7 +2032,7 @@ 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_APPEND)) {
+            (file->f_flags & O_TRUNC)) {
                 long cpu = (long) inode->i_private;
 
                 if (cpu == TRACE_PIPE_ALL_CPU)
@@ -2053,25 +2054,23 @@ static int tracing_open(struct inode *inode, struct file *file)
 static void *
 t_next(struct seq_file *m, void *v, loff_t *pos)
 {
-        struct tracer *t = m->private;
+        struct tracer *t = v;
 
         (*pos)++;
 
         if (t)
                 t = t->next;
 
-        m->private = t;
-
         return t;
 }
 
 static void *t_start(struct seq_file *m, loff_t *pos)
 {
-        struct tracer *t = m->private;
+        struct tracer *t;
         loff_t l = 0;
 
         mutex_lock(&trace_types_lock);
-        for (; t && l < *pos; t = t_next(m, t, &l))
+        for (t = trace_types; t && l < *pos; t = t_next(m, t, &l))
                 ;
 
         return t;
@@ -2107,18 +2106,10 @@ static struct seq_operations show_traces_seq_ops = {
 
 static int show_traces_open(struct inode *inode, struct file *file)
 {
-        int ret;
-
         if (tracing_disabled)
                 return -ENODEV;
 
-        ret = seq_open(file, &show_traces_seq_ops);
-        if (!ret) {
-                struct seq_file *m = file->private_data;
-                m->private = trace_types;
-        }
-
-        return ret;
+        return seq_open(file, &show_traces_seq_ops);
 }
 
 static ssize_t
@@ -3095,7 +3086,8 @@ tracing_fill_pipe_page(size_t rem, struct trace_iterator *iter)
                         break;
                 }
 
-                trace_consume(iter);
+                if (ret != TRACE_TYPE_NO_CONSUME)
+                        trace_consume(iter);
                 rem -= count;
                 if (!find_next_entry_inc(iter)) {
                         rem = 0;
@@ -4243,8 +4235,11 @@ static void __ftrace_dump(bool disable_tracing)
                 iter.pos = -1;
 
                 if (find_next_entry_inc(&iter) != NULL) {
-                        print_trace_line(&iter);
-                        trace_consume(&iter);
+                        int ret;
+
+                        ret = print_trace_line(&iter);
+                        if (ret != TRACE_TYPE_NO_CONSUME)
+                                trace_consume(&iter);
                 }
 
                 trace_printk_seq(&iter.seq);
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index 6e735d4771f8..8b9f4f6e9559 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -438,10 +438,6 @@ struct trace_entry *tracing_get_trace_entry(struct trace_array *tr,
 struct trace_entry *trace_find_next_entry(struct trace_iterator *iter,
                                           int *ent_cpu, u64 *ent_ts);
 
-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);
 
@@ -597,6 +593,7 @@ print_graph_function(struct trace_iterator *iter)
 
 extern struct pid *ftrace_pid_trace;
 
+#ifdef CONFIG_FUNCTION_TRACER
 static inline int ftrace_trace_task(struct task_struct *task)
 {
         if (!ftrace_pid_trace)
@@ -604,6 +601,12 @@ static inline int ftrace_trace_task(struct task_struct *task)
 
         return test_tsk_trace_trace(task);
 }
+#else
+static inline int ftrace_trace_task(struct task_struct *task)
+{
+        return 1;
+}
+#endif
 
 /*
  * trace_iterator_flags is an enumeration that defines bit
diff --git a/kernel/trace/trace_event_profile.c b/kernel/trace/trace_event_profile.c
index 5b5895afecfe..11ba5bb4ed0a 100644
--- a/kernel/trace/trace_event_profile.c
+++ b/kernel/trace/trace_event_profile.c
@@ -14,7 +14,7 @@ int ftrace_profile_enable(int event_id)
 
         mutex_lock(&event_mutex);
         list_for_each_entry(event, &ftrace_events, list) {
-                if (event->id == event_id) {
+                if (event->id == event_id && event->profile_enable) {
                         ret = event->profile_enable(event);
                         break;
                 }
diff --git a/kernel/trace/trace_event_types.h b/kernel/trace/trace_event_types.h
index 5e32e375134d..6db005e12487 100644
--- a/kernel/trace/trace_event_types.h
+++ b/kernel/trace/trace_event_types.h
@@ -26,6 +26,9 @@ TRACE_EVENT_FORMAT(funcgraph_exit, TRACE_GRAPH_RET,
                    ftrace_graph_ret_entry, ignore,
         TRACE_STRUCT(
                 TRACE_FIELD(unsigned long, ret.func, func)
+                TRACE_FIELD(unsigned long long, ret.calltime, calltime)
+                TRACE_FIELD(unsigned long long, ret.rettime, rettime)
+                TRACE_FIELD(unsigned long, ret.overrun, overrun)
                 TRACE_FIELD(int, ret.depth, depth)
         ),
         TP_RAW_FMT("<-- %lx (%d)")
diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
index aa08be69a1b6..e75276a49cf5 100644
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -300,10 +300,18 @@ t_next(struct seq_file *m, void *v, loff_t *pos)
 
 static void *t_start(struct seq_file *m, loff_t *pos)
 {
+        struct ftrace_event_call *call = NULL;
+        loff_t l;
+
         mutex_lock(&event_mutex);
-        if (*pos == 0)
-                m->private = ftrace_events.next;
-        return t_next(m, NULL, pos);
+
+        m->private = ftrace_events.next;
+        for (l = 0; l <= *pos; ) {
+                call = t_next(m, NULL, &l);
+                if (!call)
+                        break;
+        }
+        return call;
 }
 
 static void *
@@ -332,10 +340,18 @@ s_next(struct seq_file *m, void *v, loff_t *pos)
 
 static void *s_start(struct seq_file *m, loff_t *pos)
 {
+        struct ftrace_event_call *call = NULL;
+        loff_t l;
+
         mutex_lock(&event_mutex);
-        if (*pos == 0)
-                m->private = ftrace_events.next;
-        return s_next(m, NULL, pos);
+
+        m->private = ftrace_events.next;
+        for (l = 0; l <= *pos; ) {
+                call = s_next(m, NULL, &l);
+                if (!call)
+                        break;
+        }
+        return call;
 }
 
 static int t_show(struct seq_file *m, void *v)
@@ -360,7 +376,7 @@ ftrace_event_seq_open(struct inode *inode, struct file *file)
         const struct seq_operations *seq_ops;
 
         if ((file->f_mode & FMODE_WRITE) &&
-            !(file->f_flags & O_APPEND))
+            (file->f_flags & O_TRUNC))
                 ftrace_clear_events();
 
         seq_ops = inode->i_private;
@@ -924,7 +940,7 @@ event_create_dir(struct ftrace_event_call *call, struct dentry *d_events,
                 entry = trace_create_file("enable", 0644, call->dir, call,
                                           enable);
 
-        if (call->id)
+        if (call->id && call->profile_enable)
                 entry = trace_create_file("id", 0444, call->dir, call,
                                           id);
 
diff --git a/kernel/trace/trace_events_filter.c b/kernel/trace/trace_events_filter.c
index 936c621bbf46..f32dc9d1ea7b 100644
--- a/kernel/trace/trace_events_filter.c
+++ b/kernel/trace/trace_events_filter.c
@@ -624,9 +624,6 @@ static int filter_add_subsystem_pred(struct filter_parse_state *ps,
                 return -ENOSPC;
         }
 
-        filter->preds[filter->n_preds] = pred;
-        filter->n_preds++;
-
         list_for_each_entry(call, &ftrace_events, list) {
 
                 if (!call->define_fields)
@@ -643,6 +640,9 @@ static int filter_add_subsystem_pred(struct filter_parse_state *ps,
                 }
                 replace_filter_string(call->filter, filter_string);
         }
+
+        filter->preds[filter->n_preds] = pred;
+        filter->n_preds++;
 out:
         return err;
 }
@@ -1029,12 +1029,17 @@ static int replace_preds(struct event_subsystem *system,
 
                 if (elt->op == OP_AND || elt->op == OP_OR) {
                         pred = create_logical_pred(elt->op);
+                        if (!pred)
+                                return -ENOMEM;
                         if (call) {
                                 err = filter_add_pred(ps, call, pred);
                                 filter_free_pred(pred);
-                        } else
+                        } else {
                                 err = filter_add_subsystem_pred(ps, system,
                                                         pred, filter_string);
+                                if (err)
+                                        filter_free_pred(pred);
+                        }
                         if (err)
                                 return err;
 
@@ -1048,12 +1053,17 @@ static int replace_preds(struct event_subsystem *system,
                 }
 
                 pred = create_pred(elt->op, operand1, operand2);
+                if (!pred)
+                        return -ENOMEM;
                 if (call) {
                         err = filter_add_pred(ps, call, pred);
                         filter_free_pred(pred);
-                } else
+                } else {
                         err = filter_add_subsystem_pred(ps, system, pred,
                                                         filter_string);
+                        if (err)
+                                filter_free_pred(pred);
+                }
                 if (err)
                         return err;
 
diff --git a/kernel/trace/trace_functions.c b/kernel/trace/trace_functions.c
index 90f134764837..75ef000613c3 100644
--- a/kernel/trace/trace_functions.c
+++ b/kernel/trace/trace_functions.c
@@ -302,8 +302,7 @@ ftrace_trace_onoff_print(struct seq_file *m, unsigned long ip,
         if (count == -1)
                 seq_printf(m, ":unlimited\n");
         else
-                seq_printf(m, ":count=%ld", count);
-        seq_putc(m, '\n');
+                seq_printf(m, ":count=%ld\n", count);
 
         return 0;
 }
@@ -364,7 +363,7 @@ ftrace_trace_onoff_callback(char *glob, char *cmd, char *param, int enable)
  out_reg:
         ret = register_ftrace_function_probe(glob, ops, count);
 
-        return ret;
+        return ret < 0 ? ret : 0;
 }
 
 static struct ftrace_func_command ftrace_traceon_cmd = {
diff --git a/kernel/trace/trace_functions_graph.c b/kernel/trace/trace_functions_graph.c
index d2249abafb53..420ec3487579 100644
--- a/kernel/trace/trace_functions_graph.c
+++ b/kernel/trace/trace_functions_graph.c
@@ -843,9 +843,16 @@ print_graph_function(struct trace_iterator *iter)
 
         switch (entry->type) {
         case TRACE_GRAPH_ENT: {
-                struct ftrace_graph_ent_entry *field;
+                /*
+                 * print_graph_entry() may consume the current event,
+                 * thus @field may become invalid, so we need to save it.
+                 * sizeof(struct ftrace_graph_ent_entry) is very small,
+                 * it can be safely saved at the stack.
+                 */
+                struct ftrace_graph_ent_entry *field, saved;
                 trace_assign_type(field, entry);
-                return print_graph_entry(field, s, iter);
+                saved = *field;
+                return print_graph_entry(&saved, s, iter);
         }
         case TRACE_GRAPH_RET: {
                 struct ftrace_graph_ret_entry *field;
diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c
index 7938f3ae93e3..e0c2545622e8 100644
--- a/kernel/trace/trace_output.c
+++ b/kernel/trace/trace_output.c
@@ -27,8 +27,7 @@ void trace_print_seq(struct seq_file *m, struct trace_seq *s)
 {
         int len = s->len >= PAGE_SIZE ? PAGE_SIZE - 1 : s->len;
 
-        s->buffer[len] = 0;
-        seq_puts(m, s->buffer);
+        seq_write(m, s->buffer, len);
 
         trace_seq_init(s);
 }
diff --git a/kernel/trace/trace_printk.c b/kernel/trace/trace_printk.c
index 9bece9687b62..687699d365ae 100644
--- a/kernel/trace/trace_printk.c
+++ b/kernel/trace/trace_printk.c
@@ -155,25 +155,19 @@ int __ftrace_vprintk(unsigned long ip, const char *fmt, va_list ap)
 EXPORT_SYMBOL_GPL(__ftrace_vprintk);
 
 static void *
-t_next(struct seq_file *m, void *v, loff_t *pos)
+t_start(struct seq_file *m, loff_t *pos)
 {
-        const char **fmt = m->private;
-        const char **next = fmt;
-
-        (*pos)++;
+        const char **fmt = __start___trace_bprintk_fmt + *pos;
 
         if ((unsigned long)fmt >= (unsigned long)__stop___trace_bprintk_fmt)
                 return NULL;
-
-        next = fmt;
-        m->private = ++next;
-
         return fmt;
 }
 
-static void *t_start(struct seq_file *m, loff_t *pos)
+static void *t_next(struct seq_file *m, void * v, loff_t *pos)
 {
-        return t_next(m, NULL, pos);
+        (*pos)++;
+        return t_start(m, pos);
 }
 
 static int t_show(struct seq_file *m, void *v)
@@ -182,7 +176,7 @@ static int t_show(struct seq_file *m, void *v)
         const char *str = *fmt;
         int i;
 
-        seq_printf(m, "0x%lx : \"", (unsigned long)fmt);
+        seq_printf(m, "0x%lx : \"", *(unsigned long *)fmt);
 
         /*
          * Tabs and new lines need to be converted.
@@ -224,15 +218,7 @@ static const struct seq_operations show_format_seq_ops = {
 static int
 ftrace_formats_open(struct inode *inode, struct file *file)
 {
-        int ret;
-
-        ret = seq_open(file, &show_format_seq_ops);
-        if (!ret) {
-                struct seq_file *m = file->private_data;
-
-                m->private = __start___trace_bprintk_fmt;
-        }
-        return ret;
+        return seq_open(file, &show_format_seq_ops);
 }
 
 static const struct file_operations ftrace_formats_fops = {
diff --git a/kernel/trace/trace_stack.c b/kernel/trace/trace_stack.c
index 2d7aebd71dbd..6a2a9d484cd6 100644
--- a/kernel/trace/trace_stack.c
+++ b/kernel/trace/trace_stack.c
@@ -301,17 +301,14 @@ static const struct seq_operations stack_trace_seq_ops = {
 
 static int stack_trace_open(struct inode *inode, struct file *file)
 {
-        int ret;
-
-        ret = seq_open(file, &stack_trace_seq_ops);
-
-        return ret;
+        return seq_open(file, &stack_trace_seq_ops);
 }
 
 static const struct file_operations stack_trace_fops = {
         .open           = stack_trace_open,
         .read           = seq_read,
         .llseek         = seq_lseek,
+        .release        = seq_release,
 };
 
 int
@@ -326,10 +323,10 @@ stack_trace_sysctl(struct ctl_table *table, int write,
         ret = proc_dointvec(table, write, file, buffer, lenp, ppos);
 
         if (ret || !write ||
-            (last_stack_tracer_enabled == stack_tracer_enabled))
+            (last_stack_tracer_enabled == !!stack_tracer_enabled))
                 goto out;
 
-        last_stack_tracer_enabled = stack_tracer_enabled;
+        last_stack_tracer_enabled = !!stack_tracer_enabled;
 
         if (stack_tracer_enabled)
                 register_ftrace_function(&trace_ops);
diff --git a/kernel/trace/trace_stat.c b/kernel/trace/trace_stat.c
index c00643733f4c..aea321c82fa0 100644
--- a/kernel/trace/trace_stat.c
+++ b/kernel/trace/trace_stat.c
@@ -73,7 +73,7 @@ static struct rb_node *release_next(struct rb_node *node)
         }
 }
 
-static void reset_stat_session(struct stat_session *session)
+static void __reset_stat_session(struct stat_session *session)
 {
         struct rb_node *node = session->stat_root.rb_node;
 
@@ -83,10 +83,17 @@ static void reset_stat_session(struct stat_session *session)
         session->stat_root = RB_ROOT;
 }
 
+static void reset_stat_session(struct stat_session *session)
+{
+        mutex_lock(&session->stat_mutex);
+        __reset_stat_session(session);
+        mutex_unlock(&session->stat_mutex);
+}
+
 static void destroy_session(struct stat_session *session)
 {
         debugfs_remove(session->file);
-        reset_stat_session(session);
+        __reset_stat_session(session);
         mutex_destroy(&session->stat_mutex);
         kfree(session);
 }
@@ -150,7 +157,7 @@ static int stat_seq_init(struct stat_session *session)
         int i;
 
         mutex_lock(&session->stat_mutex);
-        reset_stat_session(session);
+        __reset_stat_session(session);
 
         if (!ts->stat_cmp)
                 ts->stat_cmp = dummy_cmp;
@@ -183,7 +190,7 @@ exit:
         return ret;
 
 exit_free_rbtree:
-        reset_stat_session(session);
+        __reset_stat_session(session);
         mutex_unlock(&session->stat_mutex);
         return ret;
 }
@@ -199,17 +206,13 @@ static void *stat_seq_start(struct seq_file *s, loff_t *pos)
         mutex_lock(&session->stat_mutex);
 
         /* If we are in the beginning of the file, print the headers */
-        if (!*pos && session->ts->stat_headers) {
-                (*pos)++;
+        if (!*pos && session->ts->stat_headers)
                 return SEQ_START_TOKEN;
-        }
 
         node = rb_first(&session->stat_root);
         for (i = 0; node && i < *pos; i++)
                 node = rb_next(node);
 
-        (*pos)++;
-
         return node;
 }
 
@@ -254,16 +257,21 @@ static const struct seq_operations trace_stat_seq_ops = {
 static int tracing_stat_open(struct inode *inode, struct file *file)
 {
         int ret;
-
+        struct seq_file *m;
         struct stat_session *session = inode->i_private;
 
+        ret = stat_seq_init(session);
+        if (ret)
+                return ret;
+
         ret = seq_open(file, &trace_stat_seq_ops);
-        if (!ret) {
-                struct seq_file *m = file->private_data;
-                m->private = session;
-                ret = stat_seq_init(session);
+        if (ret) {
+                reset_stat_session(session);
+                return ret;
         }
 
+        m = file->private_data;
+        m->private = session;
         return ret;
 }
 
@@ -274,11 +282,9 @@ static int tracing_stat_release(struct inode *i, struct file *f)
 {
         struct stat_session *session = i->i_private;
 
-        mutex_lock(&session->stat_mutex);
         reset_stat_session(session);
-        mutex_unlock(&session->stat_mutex);
 
-        return 0;
+        return seq_release(i, f);
 }
 
 static const struct file_operations tracing_stat_fops = {