14 files changed, 166 insertions, 155 deletions

diff --git a/include/trace/ftrace.h b/include/trace/ftrace.h
index d615f78cc6b6..41a6643e2136 100644
--- a/include/trace/ftrace.h
+++ b/include/trace/ftrace.h
@@ -670,10 +670,6 @@ perf_trace_##call(void *__data, proto)					\
                              sizeof(u64));                              \
         __entry_size -= sizeof(u32);                                    \
                                                                         \
-        if (WARN_ONCE(__entry_size > PERF_MAX_TRACE_SIZE,               \
-                      "profile buffer not large enough"))               \
-                return;                                                 \
-                                                                        \
         entry = (struct ftrace_raw_##call *)perf_trace_buf_prepare(     \
                 __entry_size, event_call->event.type, &__regs, &rctx);  \
         if (!entry)                                                     \
diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c
index e444ff88f0a4..cc2f66f68dc5 100644
--- a/kernel/trace/ring_buffer.c
+++ b/kernel/trace/ring_buffer.c
@@ -36,11 +36,11 @@ int ring_buffer_print_entry_header(struct trace_seq *s)
 {
         int ret;
 
-        ret = trace_seq_printf(s, "# compressed entry header\n");
-        ret = trace_seq_printf(s, "\ttype_len    :    5 bits\n");
-        ret = trace_seq_printf(s, "\ttime_delta  :   27 bits\n");
-        ret = trace_seq_printf(s, "\tarray       :   32 bits\n");
-        ret = trace_seq_printf(s, "\n");
+        ret = trace_seq_puts(s, "# compressed entry header\n");
+        ret = trace_seq_puts(s, "\ttype_len    :    5 bits\n");
+        ret = trace_seq_puts(s, "\ttime_delta  :   27 bits\n");
+        ret = trace_seq_puts(s, "\tarray       :   32 bits\n");
+        ret = trace_seq_putc(s, '\n');
         ret = trace_seq_printf(s, "\tpadding     : type == %d\n",
                                RINGBUF_TYPE_PADDING);
         ret = trace_seq_printf(s, "\ttime_extend : type == %d\n",
@@ -1066,7 +1066,7 @@ static int rb_check_list(struct ring_buffer_per_cpu *cpu_buffer,
 }
 
 /**
- * check_pages - integrity check of buffer pages
+ * rb_check_pages - integrity check of buffer pages
  * @cpu_buffer: CPU buffer with pages to test
  *
  * As a safety measure we check to make sure the data pages have not
@@ -1258,7 +1258,7 @@ static int rb_cpu_notify(struct notifier_block *self,
 #endif
 
 /**
- * ring_buffer_alloc - allocate a new ring_buffer
+ * __ring_buffer_alloc - allocate a new ring_buffer
  * @size: the size in bytes per cpu that is needed.
  * @flags: attributes to set for the ring buffer.
  *
@@ -1607,6 +1607,7 @@ static void update_pages_handler(struct work_struct *work)
  * ring_buffer_resize - resize the ring buffer
  * @buffer: the buffer to resize.
  * @size: the new size.
+ * @cpu_id: the cpu buffer to resize
  *
  * Minimum size is 2 * BUF_PAGE_SIZE.
  *
@@ -3956,11 +3957,11 @@ EXPORT_SYMBOL_GPL(ring_buffer_consume);
  * expected.
  *
  * After a sequence of ring_buffer_read_prepare calls, the user is
- * expected to make at least one call to ring_buffer_prepare_sync.
+ * expected to make at least one call to ring_buffer_read_prepare_sync.
  * Afterwards, ring_buffer_read_start is invoked to get things going
  * for real.
  *
- * This overall must be paired with ring_buffer_finish.
+ * This overall must be paired with ring_buffer_read_finish.
  */
 struct ring_buffer_iter *
 ring_buffer_read_prepare(struct ring_buffer *buffer, int cpu)
@@ -4009,7 +4010,7 @@ EXPORT_SYMBOL_GPL(ring_buffer_read_prepare_sync);
  * an intervening ring_buffer_read_prepare_sync must have been
  * performed.
  *
- * Must be paired with ring_buffer_finish.
+ * Must be paired with ring_buffer_read_finish.
  */
 void
 ring_buffer_read_start(struct ring_buffer_iter *iter)
@@ -4031,7 +4032,7 @@ ring_buffer_read_start(struct ring_buffer_iter *iter)
 EXPORT_SYMBOL_GPL(ring_buffer_read_start);
 
 /**
- * ring_buffer_finish - finish reading the iterator of the buffer
+ * ring_buffer_read_finish - finish reading the iterator of the buffer
  * @iter: The iterator retrieved by ring_buffer_start
  *
  * This re-enables the recording to the buffer, and frees the
@@ -4346,6 +4347,7 @@ EXPORT_SYMBOL_GPL(ring_buffer_swap_cpu);
 /**
  * ring_buffer_alloc_read_page - allocate a page to read from buffer
  * @buffer: the buffer to allocate for.
+ * @cpu: the cpu buffer to allocate.
  *
  * This function is used in conjunction with ring_buffer_read_page.
  * When reading a full page from the ring buffer, these functions
@@ -4403,7 +4405,7 @@ EXPORT_SYMBOL_GPL(ring_buffer_free_read_page);
  * to swap with a page in the ring buffer.
  *
  * for example:
- *      rpage = ring_buffer_alloc_read_page(buffer);
+ *      rpage = ring_buffer_alloc_read_page(buffer, cpu);
  *      if (!rpage)
  *              return error;
  *      ret = ring_buffer_read_page(buffer, &rpage, len, cpu, 0);
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 0cd500bffd9b..3f2477713aca 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -3008,7 +3008,6 @@ static int tracing_release(struct inode *inode, struct file *file)
 
         iter = m->private;
         tr = iter->tr;
-        trace_array_put(tr);
 
         mutex_lock(&trace_types_lock);
 
@@ -3023,6 +3022,9 @@ static int tracing_release(struct inode *inode, struct file *file)
         if (!iter->snapshot)
                 /* reenable tracing if it was previously enabled */
                 tracing_start_tr(tr);
+
+        __trace_array_put(tr);
+
         mutex_unlock(&trace_types_lock);
 
         mutex_destroy(&iter->mutex);
@@ -3447,6 +3449,7 @@ tracing_trace_options_write(struct file *filp, const char __user *ubuf,
 static int tracing_trace_options_open(struct inode *inode, struct file *file)
 {
         struct trace_array *tr = inode->i_private;
+        int ret;
 
         if (tracing_disabled)
                 return -ENODEV;
@@ -3454,7 +3457,11 @@ static int tracing_trace_options_open(struct inode *inode, struct file *file)
         if (trace_array_get(tr) < 0)
                 return -ENODEV;
 
-        return single_open(file, tracing_trace_options_show, inode->i_private);
+        ret = single_open(file, tracing_trace_options_show, inode->i_private);
+        if (ret < 0)
+                trace_array_put(tr);
+
+        return ret;
 }
 
 static const struct file_operations tracing_iter_fops = {
@@ -3537,14 +3544,14 @@ static const char readme_msg[] =
         "\n  snapshot\t\t- Like 'trace' but shows the content of the static snapshot buffer\n"
         "\t\t\t  Read the contents for more information\n"
 #endif
-#ifdef CONFIG_STACKTRACE
+#ifdef CONFIG_STACK_TRACER
         "  stack_trace\t\t- Shows the max stack trace when active\n"
         "  stack_max_size\t- Shows current max stack size that was traced\n"
         "\t\t\t  Write into this file to reset the max size (trigger a new trace)\n"
 #ifdef CONFIG_DYNAMIC_FTRACE
         "  stack_trace_filter\t- Like set_ftrace_filter but limits what stack_trace traces\n"
 #endif
-#endif /* CONFIG_STACKTRACE */
+#endif /* CONFIG_STACK_TRACER */
 ;
 
 static ssize_t
@@ -3958,6 +3965,7 @@ static int tracing_open_pipe(struct inode *inode, struct file *filp)
         iter = kzalloc(sizeof(*iter), GFP_KERNEL);
         if (!iter) {
                 ret = -ENOMEM;
+                __trace_array_put(tr);
                 goto out;
         }
 
@@ -4704,21 +4712,24 @@ static int tracing_snapshot_open(struct inode *inode, struct file *file)
                         ret = PTR_ERR(iter);
         } else {
                 /* Writes still need the seq_file to hold the private data */
+                ret = -ENOMEM;
                 m = kzalloc(sizeof(*m), GFP_KERNEL);
                 if (!m)
-                        return -ENOMEM;
+                        goto out;
                 iter = kzalloc(sizeof(*iter), GFP_KERNEL);
                 if (!iter) {
                         kfree(m);
-                        return -ENOMEM;
+                        goto out;
                 }
+                ret = 0;
+
                 iter->tr = tr;
                 iter->trace_buffer = &tc->tr->max_buffer;
                 iter->cpu_file = tc->cpu;
                 m->private = iter;
                 file->private_data = m;
         }
-
+out:
         if (ret < 0)
                 trace_array_put(tr);
 
@@ -4948,8 +4959,6 @@ static int tracing_buffers_open(struct inode *inode, struct file *filp)
 
         mutex_lock(&trace_types_lock);
 
-        tr->ref++;
-
         info->iter.tr           = tr;
         info->iter.cpu_file     = tc->cpu;
         info->iter.trace        = tr->current_trace;
@@ -5328,9 +5337,10 @@ tracing_stats_read(struct file *filp, char __user *ubuf,
 }
 
 static const struct file_operations tracing_stats_fops = {
-        .open           = tracing_open_generic,
+        .open           = tracing_open_generic_tc,
         .read           = tracing_stats_read,
         .llseek         = generic_file_llseek,
+        .release        = tracing_release_generic_tc,
 };
 
 #ifdef CONFIG_DYNAMIC_FTRACE
@@ -5973,8 +5983,10 @@ static int new_instance_create(const char *name)
                 goto out_free_tr;
 
         ret = event_trace_add_tracer(tr->dir, tr);
-        if (ret)
+        if (ret) {
+                debugfs_remove_recursive(tr->dir);
                 goto out_free_tr;
+        }
 
         init_tracer_debugfs(tr, tr->dir);
 
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index 4a4f6e1828b6..e7d643b8a907 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -214,7 +214,6 @@ struct trace_array {
         struct dentry           *event_dir;
         struct list_head        systems;
         struct list_head        events;
-        struct task_struct      *waiter;
         int                     ref;
 };
 
@@ -680,6 +679,15 @@ extern int trace_selftest_startup_sched_switch(struct tracer *trace,
                                                struct trace_array *tr);
 extern int trace_selftest_startup_branch(struct tracer *trace,
                                          struct trace_array *tr);
+/*
+ * Tracer data references selftest functions that only occur
+ * on boot up. These can be __init functions. Thus, when selftests
+ * are enabled, then the tracers need to reference __init functions.
+ */
+#define __tracer_data           __refdata
+#else
+/* Tracers are seldom changed. Optimize when selftests are disabled. */
+#define __tracer_data           __read_mostly
 #endif /* CONFIG_FTRACE_STARTUP_TEST */
 
 extern void *head_page(struct trace_array_cpu *data);
diff --git a/kernel/trace/trace_event_perf.c b/kernel/trace/trace_event_perf.c
index 84b1e045faba..80c36bcf66e8 100644
--- a/kernel/trace/trace_event_perf.c
+++ b/kernel/trace/trace_event_perf.c
@@ -236,6 +236,10 @@ __kprobes void *perf_trace_buf_prepare(int size, unsigned short type,
 
         BUILD_BUG_ON(PERF_MAX_TRACE_SIZE % sizeof(unsigned long));
 
+        if (WARN_ONCE(size > PERF_MAX_TRACE_SIZE,
+                        "perf buffer not large enough"))
+                return NULL;
+
         pc = preempt_count();
 
         *rctxp = perf_swevent_get_recursion_context();
@@ -266,6 +270,10 @@ perf_ftrace_function_call(unsigned long ip, unsigned long parent_ip,
         struct pt_regs regs;
         int rctx;
 
+        head = this_cpu_ptr(event_function.perf_events);
+        if (hlist_empty(head))
+                return;
+
 #define ENTRY_SIZE (ALIGN(sizeof(struct ftrace_entry) + sizeof(u32), \
                     sizeof(u64)) - sizeof(u32))
 
@@ -279,8 +287,6 @@ perf_ftrace_function_call(unsigned long ip, unsigned long parent_ip,
 
         entry->ip = ip;
         entry->parent_ip = parent_ip;
-
-        head = this_cpu_ptr(event_function.perf_events);
         perf_trace_buf_submit(entry, ENTRY_SIZE, rctx, 0,
                               1, &regs, head, NULL);
 
diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
index 7d854290bf81..898f868833f2 100644
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -826,59 +826,33 @@ enum {
 static void *f_next(struct seq_file *m, void *v, loff_t *pos)
 {
         struct ftrace_event_call *call = m->private;
-        struct ftrace_event_field *field;
         struct list_head *common_head = &ftrace_common_fields;
         struct list_head *head = trace_get_fields(call);
+        struct list_head *node = v;
 
         (*pos)++;
 
         switch ((unsigned long)v) {
         case FORMAT_HEADER:
-                if (unlikely(list_empty(common_head)))
-                        return NULL;
-
-                field = list_entry(common_head->prev,
-                                   struct ftrace_event_field, link);
-                return field;
+                node = common_head;
+                break;
 
         case FORMAT_FIELD_SEPERATOR:
-                if (unlikely(list_empty(head)))
-                        return NULL;
-
-                field = list_entry(head->prev, struct ftrace_event_field, link);
-                return field;
+                node = head;
+                break;
 
         case FORMAT_PRINTFMT:
                 /* all done */
                 return NULL;
         }
 
-        field = v;
-        if (field->link.prev == common_head)
+        node = node->prev;
+        if (node == common_head)
                 return (void *)FORMAT_FIELD_SEPERATOR;
-        else if (field->link.prev == head)
+        else if (node == head)
                 return (void *)FORMAT_PRINTFMT;
-
-        field = list_entry(field->link.prev, struct ftrace_event_field, link);
-
-        return field;
-}
-
-static void *f_start(struct seq_file *m, loff_t *pos)
-{
-        loff_t l = 0;
-        void *p;
-
-        /* Start by showing the header */
-        if (!*pos)
-                return (void *)FORMAT_HEADER;
-
-        p = (void *)FORMAT_HEADER;
-        do {
-                p = f_next(m, p, &l);
-        } while (p && l < *pos);
-
-        return p;
+        else
+                return node;
 }
 
 static int f_show(struct seq_file *m, void *v)
@@ -904,8 +878,7 @@ static int f_show(struct seq_file *m, void *v)
                 return 0;
         }
 
-        field = v;
-
+        field = list_entry(v, struct ftrace_event_field, link);
         /*
          * Smartly shows the array type(except dynamic array).
          * Normal:
@@ -932,6 +905,17 @@ static int f_show(struct seq_file *m, void *v)
         return 0;
 }
 
+static void *f_start(struct seq_file *m, loff_t *pos)
+{
+        void *p = (void *)FORMAT_HEADER;
+        loff_t l = 0;
+
+        while (l < *pos && p)
+                p = f_next(m, p, &l);
+
+        return p;
+}
+
 static void f_stop(struct seq_file *m, void *p)
 {
 }
@@ -963,23 +947,14 @@ static ssize_t
 event_id_read(struct file *filp, char __user *ubuf, size_t cnt, loff_t *ppos)
 {
         struct ftrace_event_call *call = filp->private_data;
-        struct trace_seq *s;
-        int r;
+        char buf[32];
+        int len;
 
         if (*ppos)
                 return 0;
 
-        s = kmalloc(sizeof(*s), GFP_KERNEL);
-        if (!s)
-                return -ENOMEM;
-
-        trace_seq_init(s);
-        trace_seq_printf(s, "%d\n", call->event.type);
-
-        r = simple_read_from_buffer(ubuf, cnt, ppos,
-                                    s->buffer, s->len);
-        kfree(s);
-        return r;
+        len = sprintf(buf, "%d\n", call->event.type);
+        return simple_read_from_buffer(ubuf, cnt, ppos, buf, len);
 }
 
 static ssize_t
@@ -1218,6 +1193,7 @@ show_header(struct file *filp, char __user *ubuf, size_t cnt, loff_t *ppos)
 
 static int ftrace_event_avail_open(struct inode *inode, struct file *file);
 static int ftrace_event_set_open(struct inode *inode, struct file *file);
+static int ftrace_event_release(struct inode *inode, struct file *file);
 
 static const struct seq_operations show_event_seq_ops = {
         .start = t_start,
@@ -1245,7 +1221,7 @@ static const struct file_operations ftrace_set_event_fops = {
         .read = seq_read,
         .write = ftrace_event_write,
         .llseek = seq_lseek,
-        .release = seq_release,
+        .release = ftrace_event_release,
 };
 
 static const struct file_operations ftrace_enable_fops = {
@@ -1323,6 +1299,15 @@ ftrace_event_open(struct inode *inode, struct file *file,
         return ret;
 }
 
+static int ftrace_event_release(struct inode *inode, struct file *file)
+{
+        struct trace_array *tr = inode->i_private;
+
+        trace_array_put(tr);
+
+        return seq_release(inode, file);
+}
+
 static int
 ftrace_event_avail_open(struct inode *inode, struct file *file)
 {
@@ -1336,12 +1321,19 @@ ftrace_event_set_open(struct inode *inode, struct file *file)
 {
         const struct seq_operations *seq_ops = &show_set_event_seq_ops;
         struct trace_array *tr = inode->i_private;
+        int ret;
+
+        if (trace_array_get(tr) < 0)
+                return -ENODEV;
 
         if ((file->f_mode & FMODE_WRITE) &&
             (file->f_flags & O_TRUNC))
                 ftrace_clear_events(tr);
 
-        return ftrace_event_open(inode, file, seq_ops);
+        ret = ftrace_event_open(inode, file, seq_ops);
+        if (ret < 0)
+                trace_array_put(tr);
+        return ret;
 }
 
 static struct event_subsystem *
diff --git a/kernel/trace/trace_events_filter.c b/kernel/trace/trace_events_filter.c
index 0d883dc057d6..0c7b75a8acc8 100644
--- a/kernel/trace/trace_events_filter.c
+++ b/kernel/trace/trace_events_filter.c
@@ -646,7 +646,7 @@ void print_event_filter(struct ftrace_event_call *call, struct trace_seq *s)
         if (filter && filter->filter_string)
                 trace_seq_printf(s, "%s\n", filter->filter_string);
         else
-                trace_seq_printf(s, "none\n");
+                trace_seq_puts(s, "none\n");
         mutex_unlock(&event_mutex);
 }
 
@@ -660,7 +660,7 @@ void print_subsystem_event_filter(struct event_subsystem *system,
         if (filter && filter->filter_string)
                 trace_seq_printf(s, "%s\n", filter->filter_string);
         else
-                trace_seq_printf(s, DEFAULT_SYS_FILTER_MESSAGE "\n");
+                trace_seq_puts(s, DEFAULT_SYS_FILTER_MESSAGE "\n");
         mutex_unlock(&event_mutex);
 }
 
diff --git a/kernel/trace/trace_functions.c b/kernel/trace/trace_functions.c
index b863f93b30f3..38fe1483c508 100644
--- a/kernel/trace/trace_functions.c
+++ b/kernel/trace/trace_functions.c
@@ -199,7 +199,7 @@ static int func_set_flag(u32 old_flags, u32 bit, int set)
         return 0;
 }
 
-static struct tracer function_trace __read_mostly =
+static struct tracer function_trace __tracer_data =
 {
         .name           = "function",
         .init           = function_trace_init,
diff --git a/kernel/trace/trace_functions_graph.c b/kernel/trace/trace_functions_graph.c
index 8388bc99f2ee..b5c09242683d 100644
--- a/kernel/trace/trace_functions_graph.c
+++ b/kernel/trace/trace_functions_graph.c
@@ -446,7 +446,7 @@ print_graph_proc(struct trace_seq *s, pid_t pid)
 
         /* First spaces to align center */
         for (i = 0; i < spaces / 2; i++) {
-                ret = trace_seq_printf(s, " ");
+                ret = trace_seq_putc(s, ' ');
                 if (!ret)
                         return TRACE_TYPE_PARTIAL_LINE;
         }
@@ -457,7 +457,7 @@ print_graph_proc(struct trace_seq *s, pid_t pid)
 
         /* Last spaces to align center */
         for (i = 0; i < spaces - (spaces / 2); i++) {
-                ret = trace_seq_printf(s, " ");
+                ret = trace_seq_putc(s, ' ');
                 if (!ret)
                         return TRACE_TYPE_PARTIAL_LINE;
         }
@@ -503,7 +503,7 @@ verif_pid(struct trace_seq *s, pid_t pid, int cpu, struct fgraph_data *data)
  ------------------------------------------
 
  */
-        ret = trace_seq_printf(s,
+        ret = trace_seq_puts(s,
                 " ------------------------------------------\n");
         if (!ret)
                 return TRACE_TYPE_PARTIAL_LINE;
@@ -516,7 +516,7 @@ verif_pid(struct trace_seq *s, pid_t pid, int cpu, struct fgraph_data *data)
         if (ret == TRACE_TYPE_PARTIAL_LINE)
                 return TRACE_TYPE_PARTIAL_LINE;
 
-        ret = trace_seq_printf(s, " => ");
+        ret = trace_seq_puts(s, " => ");
         if (!ret)
                 return TRACE_TYPE_PARTIAL_LINE;
 
@@ -524,7 +524,7 @@ verif_pid(struct trace_seq *s, pid_t pid, int cpu, struct fgraph_data *data)
         if (ret == TRACE_TYPE_PARTIAL_LINE)
                 return TRACE_TYPE_PARTIAL_LINE;
 
-        ret = trace_seq_printf(s,
+        ret = trace_seq_puts(s,
                 "\n ------------------------------------------\n\n");
         if (!ret)
                 return TRACE_TYPE_PARTIAL_LINE;
@@ -645,7 +645,7 @@ print_graph_irq(struct trace_iterator *iter, unsigned long addr,
                         ret = print_graph_proc(s, pid);
                         if (ret == TRACE_TYPE_PARTIAL_LINE)
                                 return TRACE_TYPE_PARTIAL_LINE;
-                        ret = trace_seq_printf(s, " | ");
+                        ret = trace_seq_puts(s, " | ");
                         if (!ret)
                                 return TRACE_TYPE_PARTIAL_LINE;
                 }
@@ -657,9 +657,9 @@ print_graph_irq(struct trace_iterator *iter, unsigned long addr,
                 return ret;
 
         if (type == TRACE_GRAPH_ENT)
-                ret = trace_seq_printf(s, "==========>");
+                ret = trace_seq_puts(s, "==========>");
         else
-                ret = trace_seq_printf(s, "<==========");
+                ret = trace_seq_puts(s, "<==========");
 
         if (!ret)
                 return TRACE_TYPE_PARTIAL_LINE;
@@ -668,7 +668,7 @@ print_graph_irq(struct trace_iterator *iter, unsigned long addr,
         if (ret != TRACE_TYPE_HANDLED)
                 return ret;
 
-        ret = trace_seq_printf(s, "\n");
+        ret = trace_seq_putc(s, '\n');
 
         if (!ret)
                 return TRACE_TYPE_PARTIAL_LINE;
@@ -705,13 +705,13 @@ trace_print_graph_duration(unsigned long long duration, struct trace_seq *s)
                 len += strlen(nsecs_str);
         }
 
-        ret = trace_seq_printf(s, " us ");
+        ret = trace_seq_puts(s, " us ");
         if (!ret)
                 return TRACE_TYPE_PARTIAL_LINE;
 
         /* Print remaining spaces to fit the row's width */
         for (i = len; i < 7; i++) {
-                ret = trace_seq_printf(s, " ");
+                ret = trace_seq_putc(s, ' ');
                 if (!ret)
                         return TRACE_TYPE_PARTIAL_LINE;
         }
@@ -731,13 +731,13 @@ print_graph_duration(unsigned long long duration, struct trace_seq *s,
         /* No real adata, just filling the column with spaces */
         switch (duration) {
         case DURATION_FILL_FULL:
-                ret = trace_seq_printf(s, "              |  ");
+                ret = trace_seq_puts(s, "              |  ");
                 return ret ? TRACE_TYPE_HANDLED : TRACE_TYPE_PARTIAL_LINE;
         case DURATION_FILL_START:
-                ret = trace_seq_printf(s, "  ");
+                ret = trace_seq_puts(s, "  ");
                 return ret ? TRACE_TYPE_HANDLED : TRACE_TYPE_PARTIAL_LINE;
         case DURATION_FILL_END:
-                ret = trace_seq_printf(s, " |");
+                ret = trace_seq_puts(s, " |");
                 return ret ? TRACE_TYPE_HANDLED : TRACE_TYPE_PARTIAL_LINE;
         }
 
@@ -745,10 +745,10 @@ print_graph_duration(unsigned long long duration, struct trace_seq *s,
         if (flags & TRACE_GRAPH_PRINT_OVERHEAD) {
                 /* Duration exceeded 100 msecs */
                 if (duration > 100000ULL)
-                        ret = trace_seq_printf(s, "! ");
+                        ret = trace_seq_puts(s, "! ");
                 /* Duration exceeded 10 msecs */
                 else if (duration > 10000ULL)
-                        ret = trace_seq_printf(s, "+ ");
+                        ret = trace_seq_puts(s, "+ ");
         }
 
         /*
@@ -757,7 +757,7 @@ print_graph_duration(unsigned long long duration, struct trace_seq *s,
          * to fill out the space.
          */
         if (ret == -1)
-                ret = trace_seq_printf(s, "  ");
+                ret = trace_seq_puts(s, "  ");
 
         /* Catching here any failure happenned above */
         if (!ret)
@@ -767,7 +767,7 @@ print_graph_duration(unsigned long long duration, struct trace_seq *s,
         if (ret != TRACE_TYPE_HANDLED)
                 return ret;
 
-        ret = trace_seq_printf(s, "|  ");
+        ret = trace_seq_puts(s, "|  ");
         if (!ret)
                 return TRACE_TYPE_PARTIAL_LINE;
 
@@ -817,7 +817,7 @@ print_graph_entry_leaf(struct trace_iterator *iter,
 
         /* Function */
         for (i = 0; i < call->depth * TRACE_GRAPH_INDENT; i++) {
-                ret = trace_seq_printf(s, " ");
+                ret = trace_seq_putc(s, ' ');
                 if (!ret)
                         return TRACE_TYPE_PARTIAL_LINE;
         }
@@ -858,7 +858,7 @@ print_graph_entry_nested(struct trace_iterator *iter,
 
         /* Function */
         for (i = 0; i < call->depth * TRACE_GRAPH_INDENT; i++) {
-                ret = trace_seq_printf(s, " ");
+                ret = trace_seq_putc(s, ' ');
                 if (!ret)
                         return TRACE_TYPE_PARTIAL_LINE;
         }
@@ -917,7 +917,7 @@ print_graph_prologue(struct trace_iterator *iter, struct trace_seq *s,
                 if (ret == TRACE_TYPE_PARTIAL_LINE)
                         return TRACE_TYPE_PARTIAL_LINE;
 
-                ret = trace_seq_printf(s, " | ");
+                ret = trace_seq_puts(s, " | ");
                 if (!ret)
                         return TRACE_TYPE_PARTIAL_LINE;
         }
@@ -1117,7 +1117,7 @@ print_graph_return(struct ftrace_graph_ret *trace, struct trace_seq *s,
 
         /* Closing brace */
         for (i = 0; i < trace->depth * TRACE_GRAPH_INDENT; i++) {
-                ret = trace_seq_printf(s, " ");
+                ret = trace_seq_putc(s, ' ');
                 if (!ret)
                         return TRACE_TYPE_PARTIAL_LINE;
         }
@@ -1129,7 +1129,7 @@ print_graph_return(struct ftrace_graph_ret *trace, struct trace_seq *s,
          * belongs to, write out the function name.
          */
         if (func_match) {
-                ret = trace_seq_printf(s, "}\n");
+                ret = trace_seq_puts(s, "}\n");
                 if (!ret)
                         return TRACE_TYPE_PARTIAL_LINE;
         } else {
@@ -1179,13 +1179,13 @@ print_graph_comment(struct trace_seq *s, struct trace_entry *ent,
         /* Indentation */
         if (depth > 0)
                 for (i = 0; i < (depth + 1) * TRACE_GRAPH_INDENT; i++) {
-                        ret = trace_seq_printf(s, " ");
+                        ret = trace_seq_putc(s, ' ');
                         if (!ret)
                                 return TRACE_TYPE_PARTIAL_LINE;
                 }
 
         /* The comment */
-        ret = trace_seq_printf(s, "/* ");
+        ret = trace_seq_puts(s, "/* ");
         if (!ret)
                 return TRACE_TYPE_PARTIAL_LINE;
 
@@ -1216,7 +1216,7 @@ print_graph_comment(struct trace_seq *s, struct trace_entry *ent,
                 s->len--;
         }
 
-        ret = trace_seq_printf(s, " */\n");
+        ret = trace_seq_puts(s, " */\n");
         if (!ret)
                 return TRACE_TYPE_PARTIAL_LINE;
 
@@ -1448,7 +1448,7 @@ static struct trace_event graph_trace_ret_event = {
         .funcs          = &graph_functions
 };
 
-static struct tracer graph_trace __read_mostly = {
+static struct tracer graph_trace __tracer_data = {
         .name           = "function_graph",
         .open           = graph_trace_open,
         .pipe_open      = graph_trace_open,
diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c
index 7ed6976493c8..3811487e7a7a 100644
--- a/kernel/trace/trace_kprobe.c
+++ b/kernel/trace/trace_kprobe.c
@@ -243,11 +243,11 @@ find_event_file_link(struct trace_probe *tp, struct ftrace_event_file *file)
 static int
 disable_trace_probe(struct trace_probe *tp, struct ftrace_event_file *file)
 {
+        struct event_file_link *link = NULL;
+        int wait = 0;
         int ret = 0;
 
         if (file) {
-                struct event_file_link *link;
-
                 link = find_event_file_link(tp, file);
                 if (!link) {
                         ret = -EINVAL;
@@ -255,10 +255,7 @@ disable_trace_probe(struct trace_probe *tp, struct ftrace_event_file *file)
                 }
 
                 list_del_rcu(&link->list);
-                /* synchronize with kprobe_trace_func/kretprobe_trace_func */
-                synchronize_sched();
-                kfree(link);
-
+                wait = 1;
                 if (!list_empty(&tp->files))
                         goto out;
 
@@ -271,8 +268,22 @@ disable_trace_probe(struct trace_probe *tp, struct ftrace_event_file *file)
                         disable_kretprobe(&tp->rp);
                 else
                         disable_kprobe(&tp->rp.kp);
+                wait = 1;
         }
  out:
+        if (wait) {
+                /*
+                 * Synchronize with kprobe_trace_func/kretprobe_trace_func
+                 * to ensure disabled (all running handlers are finished).
+                 * This is not only for kfree(), but also the caller,
+                 * trace_remove_event_call() supposes it for releasing
+                 * event_call related objects, which will be accessed in
+                 * the kprobe_trace_func/kretprobe_trace_func.
+                 */
+                synchronize_sched();
+                kfree(link);    /* Ignored if link == NULL */
+        }
+
         return ret;
 }
 
@@ -1087,9 +1098,6 @@ kprobe_perf_func(struct trace_probe *tp, struct pt_regs *regs)
         __size = sizeof(*entry) + tp->size + dsize;
         size = ALIGN(__size + sizeof(u32), sizeof(u64));
         size -= sizeof(u32);
-        if (WARN_ONCE(size > PERF_MAX_TRACE_SIZE,
-                     "profile buffer not large enough"))
-                return;
 
         entry = perf_trace_buf_prepare(size, call->event.type, regs, &rctx);
         if (!entry)
@@ -1120,9 +1128,6 @@ kretprobe_perf_func(struct trace_probe *tp, struct kretprobe_instance *ri,
         __size = sizeof(*entry) + tp->size + dsize;
         size = ALIGN(__size + sizeof(u32), sizeof(u64));
         size -= sizeof(u32);
-        if (WARN_ONCE(size > PERF_MAX_TRACE_SIZE,
-                     "profile buffer not large enough"))
-                return;
 
         entry = perf_trace_buf_prepare(size, call->event.type, regs, &rctx);
         if (!entry)
diff --git a/kernel/trace/trace_mmiotrace.c b/kernel/trace/trace_mmiotrace.c
index a5e8f4878bfa..b3dcfb2f0fef 100644
--- a/kernel/trace/trace_mmiotrace.c
+++ b/kernel/trace/trace_mmiotrace.c
@@ -90,7 +90,7 @@ static int mmio_print_pcidev(struct trace_seq *s, const struct pci_dev *dev)
         if (drv)
                 ret += trace_seq_printf(s, " %s\n", drv->name);
         else
-                ret += trace_seq_printf(s, " \n");
+                ret += trace_seq_puts(s, " \n");
         return ret;
 }
 
@@ -107,7 +107,7 @@ static void mmio_pipe_open(struct trace_iterator *iter)
         struct header_iter *hiter;
         struct trace_seq *s = &iter->seq;
 
-        trace_seq_printf(s, "VERSION 20070824\n");
+        trace_seq_puts(s, "VERSION 20070824\n");
 
         hiter = kzalloc(sizeof(*hiter), GFP_KERNEL);
         if (!hiter)
@@ -209,7 +209,7 @@ static enum print_line_t mmio_print_rw(struct trace_iterator *iter)
                         (rw->value >> 0) & 0xff, rw->pc, 0);
                 break;
         default:
-                ret = trace_seq_printf(s, "rw what?\n");
+                ret = trace_seq_puts(s, "rw what?\n");
                 break;
         }
         if (ret)
@@ -245,7 +245,7 @@ static enum print_line_t mmio_print_map(struct trace_iterator *iter)
                         secs, usec_rem, m->map_id, 0UL, 0);
                 break;
         default:
-                ret = trace_seq_printf(s, "map what?\n");
+                ret = trace_seq_puts(s, "map what?\n");
                 break;
         }
         if (ret)
diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c
index bb922d9ee51b..34e7cbac0c9c 100644
--- a/kernel/trace/trace_output.c
+++ b/kernel/trace/trace_output.c
@@ -78,7 +78,7 @@ enum print_line_t trace_print_printk_msg_only(struct trace_iterator *iter)
 
         trace_assign_type(field, entry);
 
-        ret = trace_seq_printf(s, "%s", field->buf);
+        ret = trace_seq_puts(s, field->buf);
         if (!ret)
                 return TRACE_TYPE_PARTIAL_LINE;
 
@@ -558,14 +558,14 @@ seq_print_userip_objs(const struct userstack_entry *entry, struct trace_seq *s,
                         if (ret)
                                 ret = trace_seq_puts(s, "??");
                         if (ret)
-                                ret = trace_seq_puts(s, "\n");
+                                ret = trace_seq_putc(s, '\n');
                         continue;
                 }
                 if (!ret)
                         break;
                 if (ret)
                         ret = seq_print_user_ip(s, mm, ip, sym_flags);
-                ret = trace_seq_puts(s, "\n");
+                ret = trace_seq_putc(s, '\n');
         }
 
         if (mm)
@@ -579,7 +579,7 @@ seq_print_ip_sym(struct trace_seq *s, unsigned long ip, unsigned long sym_flags)
         int ret;
 
         if (!ip)
-                return trace_seq_printf(s, "0");
+                return trace_seq_putc(s, '0');
 
         if (sym_flags & TRACE_ITER_SYM_OFFSET)
                 ret = seq_print_sym_offset(s, "%s", ip);
@@ -964,14 +964,14 @@ static enum print_line_t trace_fn_trace(struct trace_iterator *iter, int flags,
                 goto partial;
 
         if ((flags & TRACE_ITER_PRINT_PARENT) && field->parent_ip) {
-                if (!trace_seq_printf(s, " <-"))
+                if (!trace_seq_puts(s, " <-"))
                         goto partial;
                 if (!seq_print_ip_sym(s,
                                       field->parent_ip,
                                       flags))
                         goto partial;
         }
-        if (!trace_seq_printf(s, "\n"))
+        if (!trace_seq_putc(s, '\n'))
                 goto partial;
 
         return TRACE_TYPE_HANDLED;
@@ -1210,7 +1210,7 @@ static enum print_line_t trace_stack_print(struct trace_iterator *iter,
 
                 if (!seq_print_ip_sym(s, *p, flags))
                         goto partial;
-                if (!trace_seq_puts(s, "\n"))
+                if (!trace_seq_putc(s, '\n'))
                         goto partial;
         }
 
diff --git a/kernel/trace/trace_syscalls.c b/kernel/trace/trace_syscalls.c
index 322e16461072..8fd03657bc7d 100644
--- a/kernel/trace/trace_syscalls.c
+++ b/kernel/trace/trace_syscalls.c
@@ -175,7 +175,7 @@ print_syscall_exit(struct trace_iterator *iter, int flags,
         entry = syscall_nr_to_meta(syscall);
 
         if (!entry) {
-                trace_seq_printf(s, "\n");
+                trace_seq_putc(s, '\n');
                 return TRACE_TYPE_HANDLED;
         }
 
@@ -566,15 +566,15 @@ static void perf_syscall_enter(void *ignore, struct pt_regs *regs, long id)
         if (!sys_data)
                 return;
 
+        head = this_cpu_ptr(sys_data->enter_event->perf_events);
+        if (hlist_empty(head))
+                return;
+
         /* get the size after alignment with the u32 buffer size field */
         size = sizeof(unsigned long) * sys_data->nb_args + sizeof(*rec);
         size = ALIGN(size + sizeof(u32), sizeof(u64));
         size -= sizeof(u32);
 
-        if (WARN_ONCE(size > PERF_MAX_TRACE_SIZE,
-                      "perf buffer not large enough"))
-                return;
-
         rec = (struct syscall_trace_enter *)perf_trace_buf_prepare(size,
                                 sys_data->enter_event->event.type, regs, &rctx);
         if (!rec)
@@ -583,8 +583,6 @@ static void perf_syscall_enter(void *ignore, struct pt_regs *regs, long id)
         rec->nr = syscall_nr;
         syscall_get_arguments(current, regs, 0, sys_data->nb_args,
                                (unsigned long *)&rec->args);
-
-        head = this_cpu_ptr(sys_data->enter_event->perf_events);
         perf_trace_buf_submit(rec, size, rctx, 0, 1, regs, head, NULL);
 }
 
@@ -642,18 +640,14 @@ static void perf_syscall_exit(void *ignore, struct pt_regs *regs, long ret)
         if (!sys_data)
                 return;
 
+        head = this_cpu_ptr(sys_data->exit_event->perf_events);
+        if (hlist_empty(head))
+                return;
+
         /* We can probably do that at build time */
         size = ALIGN(sizeof(*rec) + sizeof(u32), sizeof(u64));
         size -= sizeof(u32);
 
-        /*
-         * Impossible, but be paranoid with the future
-         * How to put this check outside runtime?
-         */
-        if (WARN_ONCE(size > PERF_MAX_TRACE_SIZE,
-                "exit event has grown above perf buffer size"))
-                return;
-
         rec = (struct syscall_trace_exit *)perf_trace_buf_prepare(size,
                                 sys_data->exit_event->event.type, regs, &rctx);
         if (!rec)
@@ -661,8 +655,6 @@ static void perf_syscall_exit(void *ignore, struct pt_regs *regs, long ret)
 
         rec->nr = syscall_nr;
         rec->ret = syscall_get_return_value(current, regs);
-
-        head = this_cpu_ptr(sys_data->exit_event->perf_events);
         perf_trace_buf_submit(rec, size, rctx, 0, 1, regs, head, NULL);
 }
 
diff --git a/kernel/trace/trace_uprobe.c b/kernel/trace/trace_uprobe.c
index d5d0cd368a56..a23d2d71188e 100644
--- a/kernel/trace/trace_uprobe.c
+++ b/kernel/trace/trace_uprobe.c
@@ -818,8 +818,6 @@ static void uprobe_perf_print(struct trace_uprobe *tu,
 
         size = SIZEOF_TRACE_ENTRY(is_ret_probe(tu));
         size = ALIGN(size + tu->size + sizeof(u32), sizeof(u64)) - sizeof(u32);
-        if (WARN_ONCE(size > PERF_MAX_TRACE_SIZE, "profile buffer not large enough"))
-                return;
 
         preempt_disable();
         head = this_cpu_ptr(call->perf_events);