Merge branch 'perf/core' into perf/uprobes

Merge in latest upstream (and the latest perf development tree),
to prepare for tooling changes, and also to pick up v3.4 MM
changes that the uprobes code needs to take care of.

Signed-off-by: Ingo Molnar <mingo@kernel.org>

14 files changed, 796 insertions, 249 deletions

diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig
index cd3134510f3d..a1d2849f2473 100644
--- a/kernel/trace/Kconfig
+++ b/kernel/trace/Kconfig
@@ -141,7 +141,7 @@ if FTRACE
 config FUNCTION_TRACER
         bool "Kernel Function Tracer"
         depends on HAVE_FUNCTION_TRACER
-        select FRAME_POINTER if !ARM_UNWIND && !S390 && !MICROBLAZE
+        select FRAME_POINTER if !ARM_UNWIND && !PPC && !S390 && !MICROBLAZE
         select KALLSYMS
         select GENERIC_TRACER
         select CONTEXT_SWITCH_TRACER
diff --git a/kernel/trace/blktrace.c b/kernel/trace/blktrace.c
index cdea7b56b0c9..c0bd0308741c 100644
--- a/kernel/trace/blktrace.c
+++ b/kernel/trace/blktrace.c
@@ -311,13 +311,6 @@ int blk_trace_remove(struct request_queue *q)
 }
 EXPORT_SYMBOL_GPL(blk_trace_remove);
 
-static int blk_dropped_open(struct inode *inode, struct file *filp)
-{
-        filp->private_data = inode->i_private;
-
-        return 0;
-}
-
 static ssize_t blk_dropped_read(struct file *filp, char __user *buffer,
                                 size_t count, loff_t *ppos)
 {
@@ -331,18 +324,11 @@ static ssize_t blk_dropped_read(struct file *filp, char __user *buffer,
 
 static const struct file_operations blk_dropped_fops = {
         .owner =        THIS_MODULE,
-        .open =         blk_dropped_open,
+        .open =         simple_open,
         .read =         blk_dropped_read,
         .llseek =       default_llseek,
 };
 
-static int blk_msg_open(struct inode *inode, struct file *filp)
-{
-        filp->private_data = inode->i_private;
-
-        return 0;
-}
-
 static ssize_t blk_msg_write(struct file *filp, const char __user *buffer,
                                 size_t count, loff_t *ppos)
 {
@@ -371,7 +357,7 @@ static ssize_t blk_msg_write(struct file *filp, const char __user *buffer,
 
 static const struct file_operations blk_msg_fops = {
         .owner =        THIS_MODULE,
-        .open =         blk_msg_open,
+        .open =         simple_open,
         .write =        blk_msg_write,
         .llseek =       noop_llseek,
 };
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 683d559a0eef..0fa92f677c92 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -62,6 +62,8 @@
 #define FTRACE_HASH_DEFAULT_BITS 10
 #define FTRACE_HASH_MAX_BITS 12
 
+#define FL_GLOBAL_CONTROL_MASK (FTRACE_OPS_FL_GLOBAL | FTRACE_OPS_FL_CONTROL)
+
 /* ftrace_enabled is a method to turn ftrace on or off */
 int ftrace_enabled __read_mostly;
 static int last_ftrace_enabled;
@@ -89,12 +91,14 @@ static struct ftrace_ops ftrace_list_end __read_mostly = {
 };
 
 static struct ftrace_ops *ftrace_global_list __read_mostly = &ftrace_list_end;
+static struct ftrace_ops *ftrace_control_list __read_mostly = &ftrace_list_end;
 static struct ftrace_ops *ftrace_ops_list __read_mostly = &ftrace_list_end;
 ftrace_func_t ftrace_trace_function __read_mostly = ftrace_stub;
 static ftrace_func_t __ftrace_trace_function_delay __read_mostly = ftrace_stub;
 ftrace_func_t __ftrace_trace_function __read_mostly = ftrace_stub;
 ftrace_func_t ftrace_pid_function __read_mostly = ftrace_stub;
 static struct ftrace_ops global_ops;
+static struct ftrace_ops control_ops;
 
 static void
 ftrace_ops_list_func(unsigned long ip, unsigned long parent_ip);
@@ -168,6 +172,32 @@ static void ftrace_test_stop_func(unsigned long ip, unsigned long parent_ip)
 }
 #endif
 
+static void control_ops_disable_all(struct ftrace_ops *ops)
+{
+        int cpu;
+
+        for_each_possible_cpu(cpu)
+                *per_cpu_ptr(ops->disabled, cpu) = 1;
+}
+
+static int control_ops_alloc(struct ftrace_ops *ops)
+{
+        int __percpu *disabled;
+
+        disabled = alloc_percpu(int);
+        if (!disabled)
+                return -ENOMEM;
+
+        ops->disabled = disabled;
+        control_ops_disable_all(ops);
+        return 0;
+}
+
+static void control_ops_free(struct ftrace_ops *ops)
+{
+        free_percpu(ops->disabled);
+}
+
 static void update_global_ops(void)
 {
         ftrace_func_t func;
@@ -219,7 +249,8 @@ static void update_ftrace_function(void)
 #else
         __ftrace_trace_function = func;
 #endif
-        ftrace_trace_function = ftrace_test_stop_func;
+        ftrace_trace_function =
+                (func == ftrace_stub) ? func : ftrace_test_stop_func;
 #endif
 }
 
@@ -259,6 +290,26 @@ static int remove_ftrace_ops(struct ftrace_ops **list, struct ftrace_ops *ops)
         return 0;
 }
 
+static void add_ftrace_list_ops(struct ftrace_ops **list,
+                                struct ftrace_ops *main_ops,
+                                struct ftrace_ops *ops)
+{
+        int first = *list == &ftrace_list_end;
+        add_ftrace_ops(list, ops);
+        if (first)
+                add_ftrace_ops(&ftrace_ops_list, main_ops);
+}
+
+static int remove_ftrace_list_ops(struct ftrace_ops **list,
+                                  struct ftrace_ops *main_ops,
+                                  struct ftrace_ops *ops)
+{
+        int ret = remove_ftrace_ops(list, ops);
+        if (!ret && *list == &ftrace_list_end)
+                ret = remove_ftrace_ops(&ftrace_ops_list, main_ops);
+        return ret;
+}
+
 static int __register_ftrace_function(struct ftrace_ops *ops)
 {
         if (ftrace_disabled)
@@ -270,15 +321,20 @@ static int __register_ftrace_function(struct ftrace_ops *ops)
         if (WARN_ON(ops->flags & FTRACE_OPS_FL_ENABLED))
                 return -EBUSY;
 
+        /* We don't support both control and global flags set. */
+        if ((ops->flags & FL_GLOBAL_CONTROL_MASK) == FL_GLOBAL_CONTROL_MASK)
+                return -EINVAL;
+
         if (!core_kernel_data((unsigned long)ops))
                 ops->flags |= FTRACE_OPS_FL_DYNAMIC;
 
         if (ops->flags & FTRACE_OPS_FL_GLOBAL) {
-                int first = ftrace_global_list == &ftrace_list_end;
-                add_ftrace_ops(&ftrace_global_list, ops);
+                add_ftrace_list_ops(&ftrace_global_list, &global_ops, ops);
                 ops->flags |= FTRACE_OPS_FL_ENABLED;
-                if (first)
-                        add_ftrace_ops(&ftrace_ops_list, &global_ops);
+        } else if (ops->flags & FTRACE_OPS_FL_CONTROL) {
+                if (control_ops_alloc(ops))
+                        return -ENOMEM;
+                add_ftrace_list_ops(&ftrace_control_list, &control_ops, ops);
         } else
                 add_ftrace_ops(&ftrace_ops_list, ops);
 
@@ -302,11 +358,23 @@ static int __unregister_ftrace_function(struct ftrace_ops *ops)
                 return -EINVAL;
 
         if (ops->flags & FTRACE_OPS_FL_GLOBAL) {
-                ret = remove_ftrace_ops(&ftrace_global_list, ops);
-                if (!ret && ftrace_global_list == &ftrace_list_end)
-                        ret = remove_ftrace_ops(&ftrace_ops_list, &global_ops);
+                ret = remove_ftrace_list_ops(&ftrace_global_list,
+                                             &global_ops, ops);
                 if (!ret)
                         ops->flags &= ~FTRACE_OPS_FL_ENABLED;
+        } else if (ops->flags & FTRACE_OPS_FL_CONTROL) {
+                ret = remove_ftrace_list_ops(&ftrace_control_list,
+                                             &control_ops, ops);
+                if (!ret) {
+                        /*
+                         * The ftrace_ops is now removed from the list,
+                         * so there'll be no new users. We must ensure
+                         * all current users are done before we free
+                         * the control data.
+                         */
+                        synchronize_sched();
+                        control_ops_free(ops);
+                }
         } else
                 ret = remove_ftrace_ops(&ftrace_ops_list, ops);
 
@@ -1119,6 +1187,12 @@ static void free_ftrace_hash_rcu(struct ftrace_hash *hash)
         call_rcu_sched(&hash->rcu, __free_ftrace_hash_rcu);
 }
 
+void ftrace_free_filter(struct ftrace_ops *ops)
+{
+        free_ftrace_hash(ops->filter_hash);
+        free_ftrace_hash(ops->notrace_hash);
+}
+
 static struct ftrace_hash *alloc_ftrace_hash(int size_bits)
 {
         struct ftrace_hash *hash;
@@ -1129,7 +1203,7 @@ static struct ftrace_hash *alloc_ftrace_hash(int size_bits)
                 return NULL;
 
         size = 1 << size_bits;
-        hash->buckets = kzalloc(sizeof(*hash->buckets) * size, GFP_KERNEL);
+        hash->buckets = kcalloc(size, sizeof(*hash->buckets), GFP_KERNEL);
 
         if (!hash->buckets) {
                 kfree(hash);
@@ -3146,8 +3220,10 @@ ftrace_set_regex(struct ftrace_ops *ops, unsigned char *buf, int len,
         mutex_lock(&ftrace_regex_lock);
         if (reset)
                 ftrace_filter_reset(hash);
-        if (buf)
-                ftrace_match_records(hash, buf, len);
+        if (buf && !ftrace_match_records(hash, buf, len)) {
+                ret = -EINVAL;
+                goto out_regex_unlock;
+        }
 
         mutex_lock(&ftrace_lock);
         ret = ftrace_hash_move(ops, enable, orig_hash, hash);
@@ -3157,6 +3233,7 @@ ftrace_set_regex(struct ftrace_ops *ops, unsigned char *buf, int len,
 
         mutex_unlock(&ftrace_lock);
 
+ out_regex_unlock:
         mutex_unlock(&ftrace_regex_lock);
 
         free_ftrace_hash(hash);
@@ -3173,10 +3250,10 @@ ftrace_set_regex(struct ftrace_ops *ops, unsigned char *buf, int len,
  * Filters denote which functions should be enabled when tracing is enabled.
  * If @buf is NULL and reset is set, all functions will be enabled for tracing.
  */
-void ftrace_set_filter(struct ftrace_ops *ops, unsigned char *buf,
+int ftrace_set_filter(struct ftrace_ops *ops, unsigned char *buf,
                        int len, int reset)
 {
-        ftrace_set_regex(ops, buf, len, reset, 1);
+        return ftrace_set_regex(ops, buf, len, reset, 1);
 }
 EXPORT_SYMBOL_GPL(ftrace_set_filter);
 
@@ -3191,10 +3268,10 @@ EXPORT_SYMBOL_GPL(ftrace_set_filter);
  * is enabled. If @buf is NULL and reset is set, all functions will be enabled
  * for tracing.
  */
-void ftrace_set_notrace(struct ftrace_ops *ops, unsigned char *buf,
+int ftrace_set_notrace(struct ftrace_ops *ops, unsigned char *buf,
                         int len, int reset)
 {
-        ftrace_set_regex(ops, buf, len, reset, 0);
+        return ftrace_set_regex(ops, buf, len, reset, 0);
 }
 EXPORT_SYMBOL_GPL(ftrace_set_notrace);
 /**
@@ -3871,6 +3948,36 @@ ftrace_ops_test(struct ftrace_ops *ops, unsigned long ip)
 #endif /* CONFIG_DYNAMIC_FTRACE */
 
 static void
+ftrace_ops_control_func(unsigned long ip, unsigned long parent_ip)
+{
+        struct ftrace_ops *op;
+
+        if (unlikely(trace_recursion_test(TRACE_CONTROL_BIT)))
+                return;
+
+        /*
+         * Some of the ops may be dynamically allocated,
+         * they must be freed after a synchronize_sched().
+         */
+        preempt_disable_notrace();
+        trace_recursion_set(TRACE_CONTROL_BIT);
+        op = rcu_dereference_raw(ftrace_control_list);
+        while (op != &ftrace_list_end) {
+                if (!ftrace_function_local_disabled(op) &&
+                    ftrace_ops_test(op, ip))
+                        op->func(ip, parent_ip);
+
+                op = rcu_dereference_raw(op->next);
+        };
+        trace_recursion_clear(TRACE_CONTROL_BIT);
+        preempt_enable_notrace();
+}
+
+static struct ftrace_ops control_ops = {
+        .func = ftrace_ops_control_func,
+};
+
+static void
 ftrace_ops_list_func(unsigned long ip, unsigned long parent_ip)
 {
         struct ftrace_ops *op;
diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c
index f5b7b5c1195b..cf8d11e91efd 100644
--- a/kernel/trace/ring_buffer.c
+++ b/kernel/trace/ring_buffer.c
@@ -154,33 +154,10 @@ enum {
 
 static unsigned long ring_buffer_flags __read_mostly = RB_BUFFERS_ON;
 
-#define BUF_PAGE_HDR_SIZE offsetof(struct buffer_data_page, data)
-
-/**
- * tracing_on - enable all tracing buffers
- *
- * This function enables all tracing buffers that may have been
- * disabled with tracing_off.
- */
-void tracing_on(void)
-{
-        set_bit(RB_BUFFERS_ON_BIT, &ring_buffer_flags);
-}
-EXPORT_SYMBOL_GPL(tracing_on);
+/* Used for individual buffers (after the counter) */
+#define RB_BUFFER_OFF           (1 << 20)
 
-/**
- * tracing_off - turn off all tracing buffers
- *
- * This function stops all tracing buffers from recording data.
- * It does not disable any overhead the tracers themselves may
- * be causing. This function simply causes all recording to
- * the ring buffers to fail.
- */
-void tracing_off(void)
-{
-        clear_bit(RB_BUFFERS_ON_BIT, &ring_buffer_flags);
-}
-EXPORT_SYMBOL_GPL(tracing_off);
+#define BUF_PAGE_HDR_SIZE offsetof(struct buffer_data_page, data)
 
 /**
  * tracing_off_permanent - permanently disable ring buffers
@@ -193,15 +170,6 @@ void tracing_off_permanent(void)
         set_bit(RB_BUFFERS_DISABLED_BIT, &ring_buffer_flags);
 }
 
-/**
- * tracing_is_on - show state of ring buffers enabled
- */
-int tracing_is_on(void)
-{
-        return ring_buffer_flags == RB_BUFFERS_ON;
-}
-EXPORT_SYMBOL_GPL(tracing_is_on);
-
 #define RB_EVNT_HDR_SIZE (offsetof(struct ring_buffer_event, array))
 #define RB_ALIGNMENT            4U
 #define RB_MAX_SMALL_DATA       (RB_ALIGNMENT * RINGBUF_TYPE_DATA_TYPE_LEN_MAX)
@@ -2619,6 +2587,63 @@ void ring_buffer_record_enable(struct ring_buffer *buffer)
 EXPORT_SYMBOL_GPL(ring_buffer_record_enable);
 
 /**
+ * ring_buffer_record_off - stop all writes into the buffer
+ * @buffer: The ring buffer to stop writes to.
+ *
+ * This prevents all writes to the buffer. Any attempt to write
+ * to the buffer after this will fail and return NULL.
+ *
+ * This is different than ring_buffer_record_disable() as
+ * it works like an on/off switch, where as the disable() verison
+ * must be paired with a enable().
+ */
+void ring_buffer_record_off(struct ring_buffer *buffer)
+{
+        unsigned int rd;
+        unsigned int new_rd;
+
+        do {
+                rd = atomic_read(&buffer->record_disabled);
+                new_rd = rd | RB_BUFFER_OFF;
+        } while (atomic_cmpxchg(&buffer->record_disabled, rd, new_rd) != rd);
+}
+EXPORT_SYMBOL_GPL(ring_buffer_record_off);
+
+/**
+ * ring_buffer_record_on - restart writes into the buffer
+ * @buffer: The ring buffer to start writes to.
+ *
+ * This enables all writes to the buffer that was disabled by
+ * ring_buffer_record_off().
+ *
+ * This is different than ring_buffer_record_enable() as
+ * it works like an on/off switch, where as the enable() verison
+ * must be paired with a disable().
+ */
+void ring_buffer_record_on(struct ring_buffer *buffer)
+{
+        unsigned int rd;
+        unsigned int new_rd;
+
+        do {
+                rd = atomic_read(&buffer->record_disabled);
+                new_rd = rd & ~RB_BUFFER_OFF;
+        } while (atomic_cmpxchg(&buffer->record_disabled, rd, new_rd) != rd);
+}
+EXPORT_SYMBOL_GPL(ring_buffer_record_on);
+
+/**
+ * ring_buffer_record_is_on - return true if the ring buffer can write
+ * @buffer: The ring buffer to see if write is enabled
+ *
+ * Returns true if the ring buffer is in a state that it accepts writes.
+ */
+int ring_buffer_record_is_on(struct ring_buffer *buffer)
+{
+        return !atomic_read(&buffer->record_disabled);
+}
+
+/**
  * ring_buffer_record_disable_cpu - stop all writes into the cpu_buffer
  * @buffer: The ring buffer to stop writes to.
  * @cpu: The CPU buffer to stop
@@ -4039,68 +4064,6 @@ 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)
-{
-        unsigned long *p = filp->private_data;
-        char buf[64];
-        int r;
-
-        if (test_bit(RB_BUFFERS_DISABLED_BIT, p))
-                r = sprintf(buf, "permanently disabled\n");
-        else
-                r = sprintf(buf, "%d\n", test_bit(RB_BUFFERS_ON_BIT, p));
-
-        return simple_read_from_buffer(ubuf, cnt, ppos, buf, r);
-}
-
-static ssize_t
-rb_simple_write(struct file *filp, const char __user *ubuf,
-                size_t cnt, loff_t *ppos)
-{
-        unsigned long *p = filp->private_data;
-        unsigned long val;
-        int ret;
-
-        ret = kstrtoul_from_user(ubuf, cnt, 10, &val);
-        if (ret)
-                return ret;
-
-        if (val)
-                set_bit(RB_BUFFERS_ON_BIT, p);
-        else
-                clear_bit(RB_BUFFERS_ON_BIT, p);
-
-        (*ppos)++;
-
-        return cnt;
-}
-
-static const struct file_operations rb_simple_fops = {
-        .open           = tracing_open_generic,
-        .read           = rb_simple_read,
-        .write          = rb_simple_write,
-        .llseek         = default_llseek,
-};
-
-
-static __init int rb_init_debugfs(void)
-{
-        struct dentry *d_tracer;
-
-        d_tracer = tracing_init_dentry();
-
-        trace_create_file("tracing_on", 0644, d_tracer,
-                            &ring_buffer_flags, &rb_simple_fops);
-
-        return 0;
-}
-
-fs_initcall(rb_init_debugfs);
-#endif
-
 #ifdef CONFIG_HOTPLUG_CPU
 static int rb_cpu_notify(struct notifier_block *self,
                          unsigned long action, void *hcpu)
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index a3f1bc5d2a00..ed7b5d1e12f4 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -36,6 +36,7 @@
 #include <linux/ctype.h>
 #include <linux/init.h>
 #include <linux/poll.h>
+#include <linux/nmi.h>
 #include <linux/fs.h>
 
 #include "trace.h"
@@ -352,6 +353,59 @@ static void wakeup_work_handler(struct work_struct *work)
 static DECLARE_DELAYED_WORK(wakeup_work, wakeup_work_handler);
 
 /**
+ * tracing_on - enable tracing buffers
+ *
+ * This function enables tracing buffers that may have been
+ * disabled with tracing_off.
+ */
+void tracing_on(void)
+{
+        if (global_trace.buffer)
+                ring_buffer_record_on(global_trace.buffer);
+        /*
+         * This flag is only looked at when buffers haven't been
+         * allocated yet. We don't really care about the race
+         * between setting this flag and actually turning
+         * on the buffer.
+         */
+        global_trace.buffer_disabled = 0;
+}
+EXPORT_SYMBOL_GPL(tracing_on);
+
+/**
+ * tracing_off - turn off tracing buffers
+ *
+ * This function stops the tracing buffers from recording data.
+ * It does not disable any overhead the tracers themselves may
+ * be causing. This function simply causes all recording to
+ * the ring buffers to fail.
+ */
+void tracing_off(void)
+{
+        if (global_trace.buffer)
+                ring_buffer_record_on(global_trace.buffer);
+        /*
+         * This flag is only looked at when buffers haven't been
+         * allocated yet. We don't really care about the race
+         * between setting this flag and actually turning
+         * on the buffer.
+         */
+        global_trace.buffer_disabled = 1;
+}
+EXPORT_SYMBOL_GPL(tracing_off);
+
+/**
+ * tracing_is_on - show state of ring buffers enabled
+ */
+int tracing_is_on(void)
+{
+        if (global_trace.buffer)
+                return ring_buffer_record_is_on(global_trace.buffer);
+        return !global_trace.buffer_disabled;
+}
+EXPORT_SYMBOL_GPL(tracing_is_on);
+
+/**
  * trace_wake_up - wake up tasks waiting for trace input
  *
  * Schedules a delayed work to wake up any task that is blocked on the
@@ -1644,6 +1698,7 @@ __find_next_entry(struct trace_iterator *iter, int *ent_cpu,
         int cpu_file = iter->cpu_file;
         u64 next_ts = 0, ts;
         int next_cpu = -1;
+        int next_size = 0;
         int cpu;
 
         /*
@@ -1675,9 +1730,12 @@ __find_next_entry(struct trace_iterator *iter, int *ent_cpu,
                         next_cpu = cpu;
                         next_ts = ts;
                         next_lost = lost_events;
+                        next_size = iter->ent_size;
                 }
         }
 
+        iter->ent_size = next_size;
+
         if (ent_cpu)
                 *ent_cpu = next_cpu;
 
@@ -2764,12 +2822,12 @@ static const char readme_msg[] =
         "tracing mini-HOWTO:\n\n"
         "# mount -t debugfs nodev /sys/kernel/debug\n\n"
         "# cat /sys/kernel/debug/tracing/available_tracers\n"
-        "wakeup preemptirqsoff preemptoff irqsoff function sched_switch nop\n\n"
+        "wakeup wakeup_rt preemptirqsoff preemptoff irqsoff function nop\n\n"
         "# cat /sys/kernel/debug/tracing/current_tracer\n"
         "nop\n"
-        "# echo sched_switch > /sys/kernel/debug/tracing/current_tracer\n"
+        "# echo wakeup > /sys/kernel/debug/tracing/current_tracer\n"
         "# cat /sys/kernel/debug/tracing/current_tracer\n"
-        "sched_switch\n"
+        "wakeup\n"
         "# cat /sys/kernel/debug/tracing/trace_options\n"
         "noprint-parent nosym-offset nosym-addr noverbose\n"
         "# echo print-parent > /sys/kernel/debug/tracing/trace_options\n"
@@ -4567,6 +4625,55 @@ static __init void create_trace_options_dir(void)
                 create_trace_option_core_file(trace_options[i], i);
 }
 
+static ssize_t
+rb_simple_read(struct file *filp, char __user *ubuf,
+               size_t cnt, loff_t *ppos)
+{
+        struct ring_buffer *buffer = filp->private_data;
+        char buf[64];
+        int r;
+
+        if (buffer)
+                r = ring_buffer_record_is_on(buffer);
+        else
+                r = 0;
+
+        r = sprintf(buf, "%d\n", r);
+
+        return simple_read_from_buffer(ubuf, cnt, ppos, buf, r);
+}
+
+static ssize_t
+rb_simple_write(struct file *filp, const char __user *ubuf,
+                size_t cnt, loff_t *ppos)
+{
+        struct ring_buffer *buffer = filp->private_data;
+        unsigned long val;
+        int ret;
+
+        ret = kstrtoul_from_user(ubuf, cnt, 10, &val);
+        if (ret)
+                return ret;
+
+        if (buffer) {
+                if (val)
+                        ring_buffer_record_on(buffer);
+                else
+                        ring_buffer_record_off(buffer);
+        }
+
+        (*ppos)++;
+
+        return cnt;
+}
+
+static const struct file_operations rb_simple_fops = {
+        .open           = tracing_open_generic,
+        .read           = rb_simple_read,
+        .write          = rb_simple_write,
+        .llseek         = default_llseek,
+};
+
 static __init int tracer_init_debugfs(void)
 {
         struct dentry *d_tracer;
@@ -4626,6 +4733,9 @@ static __init int tracer_init_debugfs(void)
         trace_create_file("trace_clock", 0644, d_tracer, NULL,
                           &trace_clock_fops);
 
+        trace_create_file("tracing_on", 0644, d_tracer,
+                            global_trace.buffer, &rb_simple_fops);
+
 #ifdef CONFIG_DYNAMIC_FTRACE
         trace_create_file("dyn_ftrace_total_info", 0444, d_tracer,
                         &ftrace_update_tot_cnt, &tracing_dyn_info_fops);
@@ -4798,6 +4908,7 @@ __ftrace_dump(bool disable_tracing, enum ftrace_dump_mode oops_dump_mode)
                         if (ret != TRACE_TYPE_NO_CONSUME)
                                 trace_consume(&iter);
                 }
+                touch_nmi_watchdog();
 
                 trace_printk_seq(&iter.seq);
         }
@@ -4863,6 +4974,8 @@ __init static int tracer_alloc_buffers(void)
                 goto out_free_cpumask;
         }
         global_trace.entries = ring_buffer_size(global_trace.buffer);
+        if (global_trace.buffer_disabled)
+                tracing_off();
 
 
 #ifdef CONFIG_TRACER_MAX_TRACE
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index b93ecbadad6d..95059f091a24 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -56,17 +56,23 @@ enum trace_type {
 #define F_STRUCT(args...)               args
 
 #undef FTRACE_ENTRY
-#define FTRACE_ENTRY(name, struct_name, id, tstruct, print)     \
-        struct struct_name {                                    \
-                struct trace_entry      ent;                    \
-                tstruct                                         \
+#define FTRACE_ENTRY(name, struct_name, id, tstruct, print, filter)     \
+        struct struct_name {                                            \
+                struct trace_entry      ent;                            \
+                tstruct                                                 \
         }
 
 #undef TP_ARGS
 #define TP_ARGS(args...)        args
 
 #undef FTRACE_ENTRY_DUP
-#define FTRACE_ENTRY_DUP(name, name_struct, id, tstruct, printk)
+#define FTRACE_ENTRY_DUP(name, name_struct, id, tstruct, printk, filter)
+
+#undef FTRACE_ENTRY_REG
+#define FTRACE_ENTRY_REG(name, struct_name, id, tstruct, print, \
+                         filter, regfn) \
+        FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print), \
+                     filter)
 
 #include "trace_entries.h"
 
@@ -148,6 +154,7 @@ struct trace_array {
         struct ring_buffer      *buffer;
         unsigned long           entries;
         int                     cpu;
+        int                     buffer_disabled;
         cycle_t                 time_start;
         struct task_struct      *waiter;
         struct trace_array_cpu  *data[NR_CPUS];
@@ -288,6 +295,8 @@ struct tracer {
 /* for function tracing recursion */
 #define TRACE_INTERNAL_BIT              (1<<11)
 #define TRACE_GLOBAL_BIT                (1<<12)
+#define TRACE_CONTROL_BIT               (1<<13)
+
 /*
  * Abuse of the trace_recursion.
  * As we need a way to maintain state if we are tracing the function
@@ -589,6 +598,8 @@ static inline int ftrace_trace_task(struct task_struct *task)
 static inline int ftrace_is_dead(void) { return 0; }
 #endif
 
+int ftrace_event_is_function(struct ftrace_event_call *call);
+
 /*
  * struct trace_parser - servers for reading the user input separated by spaces
  * @cont: set if the input is not complete - no final space char was found
@@ -766,9 +777,7 @@ struct filter_pred {
         u64                     val;
         struct regex            regex;
         unsigned short          *ops;
-#ifdef CONFIG_FTRACE_STARTUP_TEST
         struct ftrace_event_field *field;
-#endif
         int                     offset;
         int                     not;
         int                     op;
@@ -818,12 +827,20 @@ extern const char *__start___trace_bprintk_fmt[];
 extern const char *__stop___trace_bprintk_fmt[];
 
 #undef FTRACE_ENTRY
-#define FTRACE_ENTRY(call, struct_name, id, tstruct, print)             \
+#define FTRACE_ENTRY(call, struct_name, id, tstruct, print, filter)     \
         extern struct ftrace_event_call                                 \
         __attribute__((__aligned__(4))) event_##call;
 #undef FTRACE_ENTRY_DUP
-#define FTRACE_ENTRY_DUP(call, struct_name, id, tstruct, print)         \
-        FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print))
+#define FTRACE_ENTRY_DUP(call, struct_name, id, tstruct, print, filter) \
+        FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print), \
+                     filter)
 #include "trace_entries.h"
 
+#ifdef CONFIG_FUNCTION_TRACER
+int perf_ftrace_event_register(struct ftrace_event_call *call,
+                               enum trace_reg type, void *data);
+#else
+#define perf_ftrace_event_register NULL
+#endif /* CONFIG_FUNCTION_TRACER */
+
 #endif /* _LINUX_KERNEL_TRACE_H */
diff --git a/kernel/trace/trace_entries.h b/kernel/trace/trace_entries.h
index 93365907f219..4108e1250ca2 100644
--- a/kernel/trace/trace_entries.h
+++ b/kernel/trace/trace_entries.h
@@ -55,7 +55,7 @@
 /*
  * Function trace entry - function address and parent function address:
  */
-FTRACE_ENTRY(function, ftrace_entry,
+FTRACE_ENTRY_REG(function, ftrace_entry,
 
         TRACE_FN,
 
@@ -64,7 +64,11 @@ FTRACE_ENTRY(function, ftrace_entry,
                 __field(        unsigned long,  parent_ip       )
         ),
 
-        F_printk(" %lx <-- %lx", __entry->ip, __entry->parent_ip)
+        F_printk(" %lx <-- %lx", __entry->ip, __entry->parent_ip),
+
+        FILTER_TRACE_FN,
+
+        perf_ftrace_event_register
 );
 
 /* Function call entry */
@@ -78,7 +82,9 @@ FTRACE_ENTRY(funcgraph_entry, ftrace_graph_ent_entry,
                 __field_desc(   int,            graph_ent,      depth           )
         ),
 
-        F_printk("--> %lx (%d)", __entry->func, __entry->depth)
+        F_printk("--> %lx (%d)", __entry->func, __entry->depth),
+
+        FILTER_OTHER
 );
 
 /* Function return entry */
@@ -98,7 +104,9 @@ FTRACE_ENTRY(funcgraph_exit, ftrace_graph_ret_entry,
         F_printk("<-- %lx (%d) (start: %llx  end: %llx) over: %d",
                  __entry->func, __entry->depth,
                  __entry->calltime, __entry->rettime,
-                 __entry->depth)
+                 __entry->depth),
+
+        FILTER_OTHER
 );
 
 /*
@@ -127,8 +135,9 @@ FTRACE_ENTRY(context_switch, ctx_switch_entry,
         F_printk("%u:%u:%u  ==> %u:%u:%u [%03u]",
                  __entry->prev_pid, __entry->prev_prio, __entry->prev_state,
                  __entry->next_pid, __entry->next_prio, __entry->next_state,
-                 __entry->next_cpu
-                )
+                 __entry->next_cpu),
+
+        FILTER_OTHER
 );
 
 /*
@@ -146,8 +155,9 @@ FTRACE_ENTRY_DUP(wakeup, ctx_switch_entry,
         F_printk("%u:%u:%u  ==+ %u:%u:%u [%03u]",
                  __entry->prev_pid, __entry->prev_prio, __entry->prev_state,
                  __entry->next_pid, __entry->next_prio, __entry->next_state,
-                 __entry->next_cpu
-                )
+                 __entry->next_cpu),
+
+        FILTER_OTHER
 );
 
 /*
@@ -156,6 +166,12 @@ FTRACE_ENTRY_DUP(wakeup, ctx_switch_entry,
 
 #define FTRACE_STACK_ENTRIES    8
 
+#ifndef CONFIG_64BIT
+# define IP_FMT "%08lx"
+#else
+# define IP_FMT "%016lx"
+#endif
+
 FTRACE_ENTRY(kernel_stack, stack_entry,
 
         TRACE_STACK,
@@ -165,11 +181,14 @@ FTRACE_ENTRY(kernel_stack, stack_entry,
                 __dynamic_array(unsigned long,  caller  )
         ),
 
-        F_printk("\t=> (%08lx)\n\t=> (%08lx)\n\t=> (%08lx)\n\t=> (%08lx)\n"
-                 "\t=> (%08lx)\n\t=> (%08lx)\n\t=> (%08lx)\n\t=> (%08lx)\n",
+        F_printk("\t=> (" IP_FMT ")\n\t=> (" IP_FMT ")\n\t=> (" IP_FMT ")\n"
+                 "\t=> (" IP_FMT ")\n\t=> (" IP_FMT ")\n\t=> (" IP_FMT ")\n"
+                 "\t=> (" IP_FMT ")\n\t=> (" IP_FMT ")\n",
                  __entry->caller[0], __entry->caller[1], __entry->caller[2],
                  __entry->caller[3], __entry->caller[4], __entry->caller[5],
-                 __entry->caller[6], __entry->caller[7])
+                 __entry->caller[6], __entry->caller[7]),
+
+        FILTER_OTHER
 );
 
 FTRACE_ENTRY(user_stack, userstack_entry,
@@ -181,11 +200,14 @@ FTRACE_ENTRY(user_stack, userstack_entry,
                 __array(        unsigned long,  caller, FTRACE_STACK_ENTRIES    )
         ),
 
-        F_printk("\t=> (%08lx)\n\t=> (%08lx)\n\t=> (%08lx)\n\t=> (%08lx)\n"
-                 "\t=> (%08lx)\n\t=> (%08lx)\n\t=> (%08lx)\n\t=> (%08lx)\n",
+        F_printk("\t=> (" IP_FMT ")\n\t=> (" IP_FMT ")\n\t=> (" IP_FMT ")\n"
+                 "\t=> (" IP_FMT ")\n\t=> (" IP_FMT ")\n\t=> (" IP_FMT ")\n"
+                 "\t=> (" IP_FMT ")\n\t=> (" IP_FMT ")\n",
                  __entry->caller[0], __entry->caller[1], __entry->caller[2],
                  __entry->caller[3], __entry->caller[4], __entry->caller[5],
-                 __entry->caller[6], __entry->caller[7])
+                 __entry->caller[6], __entry->caller[7]),
+
+        FILTER_OTHER
 );
 
 /*
@@ -202,7 +224,9 @@ FTRACE_ENTRY(bprint, bprint_entry,
         ),
 
         F_printk("%08lx fmt:%p",
-                 __entry->ip, __entry->fmt)
+                 __entry->ip, __entry->fmt),
+
+        FILTER_OTHER
 );
 
 FTRACE_ENTRY(print, print_entry,
@@ -215,7 +239,9 @@ FTRACE_ENTRY(print, print_entry,
         ),
 
         F_printk("%08lx %s",
-                 __entry->ip, __entry->buf)
+                 __entry->ip, __entry->buf),
+
+        FILTER_OTHER
 );
 
 FTRACE_ENTRY(mmiotrace_rw, trace_mmiotrace_rw,
@@ -234,7 +260,9 @@ FTRACE_ENTRY(mmiotrace_rw, trace_mmiotrace_rw,
 
         F_printk("%lx %lx %lx %d %x %x",
                  (unsigned long)__entry->phys, __entry->value, __entry->pc,
-                 __entry->map_id, __entry->opcode, __entry->width)
+                 __entry->map_id, __entry->opcode, __entry->width),
+
+        FILTER_OTHER
 );
 
 FTRACE_ENTRY(mmiotrace_map, trace_mmiotrace_map,
@@ -252,7 +280,9 @@ FTRACE_ENTRY(mmiotrace_map, trace_mmiotrace_map,
 
         F_printk("%lx %lx %lx %d %x",
                  (unsigned long)__entry->phys, __entry->virt, __entry->len,
-                 __entry->map_id, __entry->opcode)
+                 __entry->map_id, __entry->opcode),
+
+        FILTER_OTHER
 );
 
 
@@ -272,6 +302,8 @@ FTRACE_ENTRY(branch, trace_branch,
 
         F_printk("%u:%s:%s (%u)",
                  __entry->line,
-                 __entry->func, __entry->file, __entry->correct)
+                 __entry->func, __entry->file, __entry->correct),
+
+        FILTER_OTHER
 );
 
diff --git a/kernel/trace/trace_event_perf.c b/kernel/trace/trace_event_perf.c
index 19a359d5e6d5..fee3752ae8f6 100644
--- a/kernel/trace/trace_event_perf.c
+++ b/kernel/trace/trace_event_perf.c
@@ -24,6 +24,11 @@ static int	total_ref_count;
 static int perf_trace_event_perm(struct ftrace_event_call *tp_event,
                                  struct perf_event *p_event)
 {
+        /* The ftrace function trace is allowed only for root. */
+        if (ftrace_event_is_function(tp_event) &&
+            perf_paranoid_kernel() && !capable(CAP_SYS_ADMIN))
+                return -EPERM;
+
         /* No tracing, just counting, so no obvious leak */
         if (!(p_event->attr.sample_type & PERF_SAMPLE_RAW))
                 return 0;
@@ -44,23 +49,17 @@ static int perf_trace_event_perm(struct ftrace_event_call *tp_event,
         return 0;
 }
 
-static int perf_trace_event_init(struct ftrace_event_call *tp_event,
-                                 struct perf_event *p_event)
+static int perf_trace_event_reg(struct ftrace_event_call *tp_event,
+                                struct perf_event *p_event)
 {
         struct hlist_head __percpu *list;
-        int ret;
+        int ret = -ENOMEM;
         int cpu;
 
-        ret = perf_trace_event_perm(tp_event, p_event);
-        if (ret)
-                return ret;
-
         p_event->tp_event = tp_event;
         if (tp_event->perf_refcount++ > 0)
                 return 0;
 
-        ret = -ENOMEM;
-
         list = alloc_percpu(struct hlist_head);
         if (!list)
                 goto fail;
@@ -83,7 +82,7 @@ static int perf_trace_event_init(struct ftrace_event_call *tp_event,
                 }
         }
 
-        ret = tp_event->class->reg(tp_event, TRACE_REG_PERF_REGISTER);
+        ret = tp_event->class->reg(tp_event, TRACE_REG_PERF_REGISTER, NULL);
         if (ret)
                 goto fail;
 
@@ -108,6 +107,69 @@ fail:
         return ret;
 }
 
+static void perf_trace_event_unreg(struct perf_event *p_event)
+{
+        struct ftrace_event_call *tp_event = p_event->tp_event;
+        int i;
+
+        if (--tp_event->perf_refcount > 0)
+                goto out;
+
+        tp_event->class->reg(tp_event, TRACE_REG_PERF_UNREGISTER, NULL);
+
+        /*
+         * Ensure our callback won't be called anymore. The buffers
+         * will be freed after that.
+         */
+        tracepoint_synchronize_unregister();
+
+        free_percpu(tp_event->perf_events);
+        tp_event->perf_events = NULL;
+
+        if (!--total_ref_count) {
+                for (i = 0; i < PERF_NR_CONTEXTS; i++) {
+                        free_percpu(perf_trace_buf[i]);
+                        perf_trace_buf[i] = NULL;
+                }
+        }
+out:
+        module_put(tp_event->mod);
+}
+
+static int perf_trace_event_open(struct perf_event *p_event)
+{
+        struct ftrace_event_call *tp_event = p_event->tp_event;
+        return tp_event->class->reg(tp_event, TRACE_REG_PERF_OPEN, p_event);
+}
+
+static void perf_trace_event_close(struct perf_event *p_event)
+{
+        struct ftrace_event_call *tp_event = p_event->tp_event;
+        tp_event->class->reg(tp_event, TRACE_REG_PERF_CLOSE, p_event);
+}
+
+static int perf_trace_event_init(struct ftrace_event_call *tp_event,
+                                 struct perf_event *p_event)
+{
+        int ret;
+
+        ret = perf_trace_event_perm(tp_event, p_event);
+        if (ret)
+                return ret;
+
+        ret = perf_trace_event_reg(tp_event, p_event);
+        if (ret)
+                return ret;
+
+        ret = perf_trace_event_open(p_event);
+        if (ret) {
+                perf_trace_event_unreg(p_event);
+                return ret;
+        }
+
+        return 0;
+}
+
 int perf_trace_init(struct perf_event *p_event)
 {
         struct ftrace_event_call *tp_event;
@@ -130,6 +192,14 @@ int perf_trace_init(struct perf_event *p_event)
         return ret;
 }
 
+void perf_trace_destroy(struct perf_event *p_event)
+{
+        mutex_lock(&event_mutex);
+        perf_trace_event_close(p_event);
+        perf_trace_event_unreg(p_event);
+        mutex_unlock(&event_mutex);
+}
+
 int perf_trace_add(struct perf_event *p_event, int flags)
 {
         struct ftrace_event_call *tp_event = p_event->tp_event;
@@ -146,43 +216,14 @@ int perf_trace_add(struct perf_event *p_event, int flags)
         list = this_cpu_ptr(pcpu_list);
         hlist_add_head_rcu(&p_event->hlist_entry, list);
 
-        return 0;
+        return tp_event->class->reg(tp_event, TRACE_REG_PERF_ADD, p_event);
 }
 
 void perf_trace_del(struct perf_event *p_event, int flags)
 {
-        hlist_del_rcu(&p_event->hlist_entry);
-}
-
-void perf_trace_destroy(struct perf_event *p_event)
-{
         struct ftrace_event_call *tp_event = p_event->tp_event;
-        int i;
-
-        mutex_lock(&event_mutex);
-        if (--tp_event->perf_refcount > 0)
-                goto out;
-
-        tp_event->class->reg(tp_event, TRACE_REG_PERF_UNREGISTER);
-
-        /*
-         * Ensure our callback won't be called anymore. The buffers
-         * will be freed after that.
-         */
-        tracepoint_synchronize_unregister();
-
-        free_percpu(tp_event->perf_events);
-        tp_event->perf_events = NULL;
-
-        if (!--total_ref_count) {
-                for (i = 0; i < PERF_NR_CONTEXTS; i++) {
-                        free_percpu(perf_trace_buf[i]);
-                        perf_trace_buf[i] = NULL;
-                }
-        }
-out:
-        module_put(tp_event->mod);
-        mutex_unlock(&event_mutex);
+        hlist_del_rcu(&p_event->hlist_entry);
+        tp_event->class->reg(tp_event, TRACE_REG_PERF_DEL, p_event);
 }
 
 __kprobes void *perf_trace_buf_prepare(int size, unsigned short type,
@@ -214,3 +255,86 @@ __kprobes void *perf_trace_buf_prepare(int size, unsigned short type,
         return raw_data;
 }
 EXPORT_SYMBOL_GPL(perf_trace_buf_prepare);
+
+#ifdef CONFIG_FUNCTION_TRACER
+static void
+perf_ftrace_function_call(unsigned long ip, unsigned long parent_ip)
+{
+        struct ftrace_entry *entry;
+        struct hlist_head *head;
+        struct pt_regs regs;
+        int rctx;
+
+#define ENTRY_SIZE (ALIGN(sizeof(struct ftrace_entry) + sizeof(u32), \
+                    sizeof(u64)) - sizeof(u32))
+
+        BUILD_BUG_ON(ENTRY_SIZE > PERF_MAX_TRACE_SIZE);
+
+        perf_fetch_caller_regs(&regs);
+
+        entry = perf_trace_buf_prepare(ENTRY_SIZE, TRACE_FN, NULL, &rctx);
+        if (!entry)
+                return;
+
+        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);
+
+#undef ENTRY_SIZE
+}
+
+static int perf_ftrace_function_register(struct perf_event *event)
+{
+        struct ftrace_ops *ops = &event->ftrace_ops;
+
+        ops->flags |= FTRACE_OPS_FL_CONTROL;
+        ops->func = perf_ftrace_function_call;
+        return register_ftrace_function(ops);
+}
+
+static int perf_ftrace_function_unregister(struct perf_event *event)
+{
+        struct ftrace_ops *ops = &event->ftrace_ops;
+        int ret = unregister_ftrace_function(ops);
+        ftrace_free_filter(ops);
+        return ret;
+}
+
+static void perf_ftrace_function_enable(struct perf_event *event)
+{
+        ftrace_function_local_enable(&event->ftrace_ops);
+}
+
+static void perf_ftrace_function_disable(struct perf_event *event)
+{
+        ftrace_function_local_disable(&event->ftrace_ops);
+}
+
+int perf_ftrace_event_register(struct ftrace_event_call *call,
+                               enum trace_reg type, void *data)
+{
+        switch (type) {
+        case TRACE_REG_REGISTER:
+        case TRACE_REG_UNREGISTER:
+                break;
+        case TRACE_REG_PERF_REGISTER:
+        case TRACE_REG_PERF_UNREGISTER:
+                return 0;
+        case TRACE_REG_PERF_OPEN:
+                return perf_ftrace_function_register(data);
+        case TRACE_REG_PERF_CLOSE:
+                return perf_ftrace_function_unregister(data);
+        case TRACE_REG_PERF_ADD:
+                perf_ftrace_function_enable(data);
+                return 0;
+        case TRACE_REG_PERF_DEL:
+                perf_ftrace_function_disable(data);
+                return 0;
+        }
+
+        return -EINVAL;
+}
+#endif /* CONFIG_FUNCTION_TRACER */
diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
index c212a7f934ec..079a93ae8a9d 100644
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -147,7 +147,8 @@ int trace_event_raw_init(struct ftrace_event_call *call)
 }
 EXPORT_SYMBOL_GPL(trace_event_raw_init);
 
-int ftrace_event_reg(struct ftrace_event_call *call, enum trace_reg type)
+int ftrace_event_reg(struct ftrace_event_call *call,
+                     enum trace_reg type, void *data)
 {
         switch (type) {
         case TRACE_REG_REGISTER:
@@ -170,6 +171,11 @@ int ftrace_event_reg(struct ftrace_event_call *call, enum trace_reg type)
                                             call->class->perf_probe,
                                             call);
                 return 0;
+        case TRACE_REG_PERF_OPEN:
+        case TRACE_REG_PERF_CLOSE:
+        case TRACE_REG_PERF_ADD:
+        case TRACE_REG_PERF_DEL:
+                return 0;
 #endif
         }
         return 0;
@@ -209,7 +215,7 @@ static int ftrace_event_enable_disable(struct ftrace_event_call *call,
                                 tracing_stop_cmdline_record();
                                 call->flags &= ~TRACE_EVENT_FL_RECORDED_CMD;
                         }
-                        call->class->reg(call, TRACE_REG_UNREGISTER);
+                        call->class->reg(call, TRACE_REG_UNREGISTER, NULL);
                 }
                 break;
         case 1:
@@ -218,7 +224,7 @@ static int ftrace_event_enable_disable(struct ftrace_event_call *call,
                                 tracing_start_cmdline_record();
                                 call->flags |= TRACE_EVENT_FL_RECORDED_CMD;
                         }
-                        ret = call->class->reg(call, TRACE_REG_REGISTER);
+                        ret = call->class->reg(call, TRACE_REG_REGISTER, NULL);
                         if (ret) {
                                 tracing_stop_cmdline_record();
                                 pr_info("event trace: Could not enable event "
diff --git a/kernel/trace/trace_events_filter.c b/kernel/trace/trace_events_filter.c
index 24aee7127451..431dba8b7542 100644
--- a/kernel/trace/trace_events_filter.c
+++ b/kernel/trace/trace_events_filter.c
@@ -81,6 +81,7 @@ enum {
         FILT_ERR_TOO_MANY_PREDS,
         FILT_ERR_MISSING_FIELD,
         FILT_ERR_INVALID_FILTER,
+        FILT_ERR_IP_FIELD_ONLY,
 };
 
 static char *err_text[] = {
@@ -96,6 +97,7 @@ static char *err_text[] = {
         "Too many terms in predicate expression",
         "Missing field name and/or value",
         "Meaningless filter expression",
+        "Only 'ip' field is supported for function trace",
 };
 
 struct opstack_op {
@@ -685,7 +687,7 @@ find_event_field(struct ftrace_event_call *call, char *name)
 
 static int __alloc_pred_stack(struct pred_stack *stack, int n_preds)
 {
-        stack->preds = kzalloc(sizeof(*stack->preds)*(n_preds + 1), GFP_KERNEL);
+        stack->preds = kcalloc(n_preds + 1, sizeof(*stack->preds), GFP_KERNEL);
         if (!stack->preds)
                 return -ENOMEM;
         stack->index = n_preds;
@@ -826,8 +828,7 @@ static int __alloc_preds(struct event_filter *filter, int n_preds)
         if (filter->preds)
                 __free_preds(filter);
 
-        filter->preds =
-                kzalloc(sizeof(*filter->preds) * n_preds, GFP_KERNEL);
+        filter->preds = kcalloc(n_preds, sizeof(*filter->preds), GFP_KERNEL);
 
         if (!filter->preds)
                 return -ENOMEM;
@@ -900,6 +901,11 @@ int filter_assign_type(const char *type)
         return FILTER_OTHER;
 }
 
+static bool is_function_field(struct ftrace_event_field *field)
+{
+        return field->filter_type == FILTER_TRACE_FN;
+}
+
 static bool is_string_field(struct ftrace_event_field *field)
 {
         return field->filter_type == FILTER_DYN_STRING ||
@@ -987,6 +993,11 @@ static int init_pred(struct filter_parse_state *ps,
                         fn = filter_pred_strloc;
                 else
                         fn = filter_pred_pchar;
+        } else if (is_function_field(field)) {
+                if (strcmp(field->name, "ip")) {
+                        parse_error(ps, FILT_ERR_IP_FIELD_ONLY, 0);
+                        return -EINVAL;
+                }
         } else {
                 if (field->is_signed)
                         ret = strict_strtoll(pred->regex.pattern, 0, &val);
@@ -1334,10 +1345,7 @@ static struct filter_pred *create_pred(struct filter_parse_state *ps,
 
         strcpy(pred.regex.pattern, operand2);
         pred.regex.len = strlen(pred.regex.pattern);
-
-#ifdef CONFIG_FTRACE_STARTUP_TEST
         pred.field = field;
-#endif
         return init_pred(ps, field, &pred) ? NULL : &pred;
 }
 
@@ -1486,7 +1494,7 @@ static int fold_pred(struct filter_pred *preds, struct filter_pred *root)
         children = count_leafs(preds, &preds[root->left]);
         children += count_leafs(preds, &preds[root->right]);
 
-        root->ops = kzalloc(sizeof(*root->ops) * children, GFP_KERNEL);
+        root->ops = kcalloc(children, sizeof(*root->ops), GFP_KERNEL);
         if (!root->ops)
                 return -ENOMEM;
 
@@ -1950,6 +1958,148 @@ void ftrace_profile_free_filter(struct perf_event *event)
         __free_filter(filter);
 }
 
+struct function_filter_data {
+        struct ftrace_ops *ops;
+        int first_filter;
+        int first_notrace;
+};
+
+#ifdef CONFIG_FUNCTION_TRACER
+static char **
+ftrace_function_filter_re(char *buf, int len, int *count)
+{
+        char *str, *sep, **re;
+
+        str = kstrndup(buf, len, GFP_KERNEL);
+        if (!str)
+                return NULL;
+
+        /*
+         * The argv_split function takes white space
+         * as a separator, so convert ',' into spaces.
+         */
+        while ((sep = strchr(str, ',')))
+                *sep = ' ';
+
+        re = argv_split(GFP_KERNEL, str, count);
+        kfree(str);
+        return re;
+}
+
+static int ftrace_function_set_regexp(struct ftrace_ops *ops, int filter,
+                                      int reset, char *re, int len)
+{
+        int ret;
+
+        if (filter)
+                ret = ftrace_set_filter(ops, re, len, reset);
+        else
+                ret = ftrace_set_notrace(ops, re, len, reset);
+
+        return ret;
+}
+
+static int __ftrace_function_set_filter(int filter, char *buf, int len,
+                                        struct function_filter_data *data)
+{
+        int i, re_cnt, ret;
+        int *reset;
+        char **re;
+
+        reset = filter ? &data->first_filter : &data->first_notrace;
+
+        /*
+         * The 'ip' field could have multiple filters set, separated
+         * either by space or comma. We first cut the filter and apply
+         * all pieces separatelly.
+         */
+        re = ftrace_function_filter_re(buf, len, &re_cnt);
+        if (!re)
+                return -EINVAL;
+
+        for (i = 0; i < re_cnt; i++) {
+                ret = ftrace_function_set_regexp(data->ops, filter, *reset,
+                                                 re[i], strlen(re[i]));
+                if (ret)
+                        break;
+
+                if (*reset)
+                        *reset = 0;
+        }
+
+        argv_free(re);
+        return ret;
+}
+
+static int ftrace_function_check_pred(struct filter_pred *pred, int leaf)
+{
+        struct ftrace_event_field *field = pred->field;
+
+        if (leaf) {
+                /*
+                 * Check the leaf predicate for function trace, verify:
+                 *  - only '==' and '!=' is used
+                 *  - the 'ip' field is used
+                 */
+                if ((pred->op != OP_EQ) && (pred->op != OP_NE))
+                        return -EINVAL;
+
+                if (strcmp(field->name, "ip"))
+                        return -EINVAL;
+        } else {
+                /*
+                 * Check the non leaf predicate for function trace, verify:
+                 *  - only '||' is used
+                */
+                if (pred->op != OP_OR)
+                        return -EINVAL;
+        }
+
+        return 0;
+}
+
+static int ftrace_function_set_filter_cb(enum move_type move,
+                                         struct filter_pred *pred,
+                                         int *err, void *data)
+{
+        /* Checking the node is valid for function trace. */
+        if ((move != MOVE_DOWN) ||
+            (pred->left != FILTER_PRED_INVALID)) {
+                *err = ftrace_function_check_pred(pred, 0);
+        } else {
+                *err = ftrace_function_check_pred(pred, 1);
+                if (*err)
+                        return WALK_PRED_ABORT;
+
+                *err = __ftrace_function_set_filter(pred->op == OP_EQ,
+                                                    pred->regex.pattern,
+                                                    pred->regex.len,
+                                                    data);
+        }
+
+        return (*err) ? WALK_PRED_ABORT : WALK_PRED_DEFAULT;
+}
+
+static int ftrace_function_set_filter(struct perf_event *event,
+                                      struct event_filter *filter)
+{
+        struct function_filter_data data = {
+                .first_filter  = 1,
+                .first_notrace = 1,
+                .ops           = &event->ftrace_ops,
+        };
+
+        return walk_pred_tree(filter->preds, filter->root,
+                              ftrace_function_set_filter_cb, &data);
+}
+#else
+static int ftrace_function_set_filter(struct perf_event *event,
+                                      struct event_filter *filter)
+{
+        return -ENODEV;
+}
+#endif /* CONFIG_FUNCTION_TRACER */
+
 int ftrace_profile_set_filter(struct perf_event *event, int event_id,
                               char *filter_str)
 {
@@ -1970,9 +2120,16 @@ int ftrace_profile_set_filter(struct perf_event *event, int event_id,
                 goto out_unlock;
 
         err = create_filter(call, filter_str, false, &filter);
-        if (!err)
-                event->filter = filter;
+        if (err)
+                goto free_filter;
+
+        if (ftrace_event_is_function(call))
+                err = ftrace_function_set_filter(event, filter);
         else
+                event->filter = filter;
+
+free_filter:
+        if (err || ftrace_event_is_function(call))
                 __free_filter(filter);
 
 out_unlock:
diff --git a/kernel/trace/trace_export.c b/kernel/trace/trace_export.c
index bbeec31e0ae3..3dd15e8bc856 100644
--- a/kernel/trace/trace_export.c
+++ b/kernel/trace/trace_export.c
@@ -18,6 +18,16 @@
 #undef TRACE_SYSTEM
 #define TRACE_SYSTEM    ftrace
 
+/*
+ * The FTRACE_ENTRY_REG macro allows ftrace entry to define register
+ * function and thus become accesible via perf.
+ */
+#undef FTRACE_ENTRY_REG
+#define FTRACE_ENTRY_REG(name, struct_name, id, tstruct, print, \
+                         filter, regfn) \
+        FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print), \
+                     filter)
+
 /* not needed for this file */
 #undef __field_struct
 #define __field_struct(type, item)
@@ -44,21 +54,22 @@
 #define F_printk(fmt, args...) fmt, args
 
 #undef FTRACE_ENTRY
-#define FTRACE_ENTRY(name, struct_name, id, tstruct, print)     \
-struct ____ftrace_##name {                                      \
-        tstruct                                                 \
-};                                                              \
-static void __always_unused ____ftrace_check_##name(void)       \
-{                                                               \
-        struct ____ftrace_##name *__entry = NULL;               \
-                                                                \
-        /* force compile-time check on F_printk() */            \
-        printk(print);                                          \
+#define FTRACE_ENTRY(name, struct_name, id, tstruct, print, filter)     \
+struct ____ftrace_##name {                                              \
+        tstruct                                                         \
+};                                                                      \
+static void __always_unused ____ftrace_check_##name(void)               \
+{                                                                       \
+        struct ____ftrace_##name *__entry = NULL;                       \
+                                                                        \
+        /* force compile-time check on F_printk() */                    \
+        printk(print);                                                  \
 }
 
 #undef FTRACE_ENTRY_DUP
-#define FTRACE_ENTRY_DUP(name, struct_name, id, tstruct, print) \
-        FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print))
+#define FTRACE_ENTRY_DUP(name, struct_name, id, tstruct, print, filter) \
+        FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print), \
+                     filter)
 
 #include "trace_entries.h"
 
@@ -67,7 +78,7 @@ static void __always_unused ____ftrace_check_##name(void)	\
         ret = trace_define_field(event_call, #type, #item,              \
                                  offsetof(typeof(field), item),         \
                                  sizeof(field.item),                    \
-                                 is_signed_type(type), FILTER_OTHER);   \
+                                 is_signed_type(type), filter_type);    \
         if (ret)                                                        \
                 return ret;
 
@@ -77,7 +88,7 @@ static void __always_unused ____ftrace_check_##name(void)	\
                                  offsetof(typeof(field),                \
                                           container.item),              \
                                  sizeof(field.container.item),          \
-                                 is_signed_type(type), FILTER_OTHER);   \
+                                 is_signed_type(type), filter_type);    \
         if (ret)                                                        \
                 return ret;
 
@@ -91,7 +102,7 @@ static void __always_unused ____ftrace_check_##name(void)	\
                 ret = trace_define_field(event_call, event_storage, #item, \
                                  offsetof(typeof(field), item),         \
                                  sizeof(field.item),                    \
-                                 is_signed_type(type), FILTER_OTHER);   \
+                                 is_signed_type(type), filter_type);    \
                 mutex_unlock(&event_storage_mutex);                     \
                 if (ret)                                                \
                         return ret;                                     \
@@ -104,7 +115,7 @@ static void __always_unused ____ftrace_check_##name(void)	\
                                  offsetof(typeof(field),                \
                                           container.item),              \
                                  sizeof(field.container.item),          \
-                                 is_signed_type(type), FILTER_OTHER);   \
+                                 is_signed_type(type), filter_type);    \
         if (ret)                                                        \
                 return ret;
 
@@ -112,17 +123,18 @@ static void __always_unused ____ftrace_check_##name(void)	\
 #define __dynamic_array(type, item)                                     \
         ret = trace_define_field(event_call, #type, #item,              \
                                  offsetof(typeof(field), item),         \
-                                 0, is_signed_type(type), FILTER_OTHER);\
+                                 0, is_signed_type(type), filter_type);\
         if (ret)                                                        \
                 return ret;
 
 #undef FTRACE_ENTRY
-#define FTRACE_ENTRY(name, struct_name, id, tstruct, print)             \
+#define FTRACE_ENTRY(name, struct_name, id, tstruct, print, filter)     \
 int                                                                     \
 ftrace_define_fields_##name(struct ftrace_event_call *event_call)       \
 {                                                                       \
         struct struct_name field;                                       \
         int ret;                                                        \
+        int filter_type = filter;                                       \
                                                                         \
         tstruct;                                                        \
                                                                         \
@@ -150,15 +162,17 @@ ftrace_define_fields_##name(struct ftrace_event_call *event_call)	\
 #define __dynamic_array(type, item)
 
 #undef F_printk
-#define F_printk(fmt, args...) #fmt ", "  __stringify(args)
+#define F_printk(fmt, args...) __stringify(fmt) ", "  __stringify(args)
 
-#undef FTRACE_ENTRY
-#define FTRACE_ENTRY(call, struct_name, etype, tstruct, print)          \
+#undef FTRACE_ENTRY_REG
+#define FTRACE_ENTRY_REG(call, struct_name, etype, tstruct, print, filter,\
+                         regfn)                                         \
                                                                         \
 struct ftrace_event_class event_class_ftrace_##call = {                 \
         .system                 = __stringify(TRACE_SYSTEM),            \
         .define_fields          = ftrace_define_fields_##call,          \
         .fields                 = LIST_HEAD_INIT(event_class_ftrace_##call.fields),\
+        .reg                    = regfn,                                \
 };                                                                      \
                                                                         \
 struct ftrace_event_call __used event_##call = {                        \
@@ -170,4 +184,14 @@ struct ftrace_event_call __used event_##call = {			\
 struct ftrace_event_call __used                                         \
 __attribute__((section("_ftrace_events"))) *__event_##call = &event_##call;
 
+#undef FTRACE_ENTRY
+#define FTRACE_ENTRY(call, struct_name, etype, tstruct, print, filter)  \
+        FTRACE_ENTRY_REG(call, struct_name, etype,                      \
+                         PARAMS(tstruct), PARAMS(print), filter, NULL)
+
+int ftrace_event_is_function(struct ftrace_event_call *call)
+{
+        return call == &event_function;
+}
+
 #include "trace_entries.h"
diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c
index 00d527c945a4..580a05ec926b 100644
--- a/kernel/trace/trace_kprobe.c
+++ b/kernel/trace/trace_kprobe.c
@@ -1892,7 +1892,8 @@ static __kprobes void kretprobe_perf_func(struct kretprobe_instance *ri,
 #endif  /* CONFIG_PERF_EVENTS */
 
 static __kprobes
-int kprobe_register(struct ftrace_event_call *event, enum trace_reg type)
+int kprobe_register(struct ftrace_event_call *event,
+                    enum trace_reg type, void *data)
 {
         struct trace_probe *tp = (struct trace_probe *)event->data;
 
@@ -1909,6 +1910,11 @@ int kprobe_register(struct ftrace_event_call *event, enum trace_reg type)
         case TRACE_REG_PERF_UNREGISTER:
                 disable_trace_probe(tp, TP_FLAG_PROFILE);
                 return 0;
+        case TRACE_REG_PERF_OPEN:
+        case TRACE_REG_PERF_CLOSE:
+        case TRACE_REG_PERF_ADD:
+        case TRACE_REG_PERF_DEL:
+                return 0;
 #endif
         }
         return 0;
diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c
index 0d6ff3555942..859fae6b1825 100644
--- a/kernel/trace/trace_output.c
+++ b/kernel/trace/trace_output.c
@@ -264,7 +264,7 @@ void *trace_seq_reserve(struct trace_seq *s, size_t len)
         return ret;
 }
 
-int trace_seq_path(struct trace_seq *s, struct path *path)
+int trace_seq_path(struct trace_seq *s, const struct path *path)
 {
         unsigned char *p;
 
@@ -300,7 +300,7 @@ ftrace_print_flags_seq(struct trace_seq *p, const char *delim,
         unsigned long mask;
         const char *str;
         const char *ret = p->buffer + p->len;
-        int i;
+        int i, first = 1;
 
         for (i = 0;  flag_array[i].name && flags; i++) {
 
@@ -310,14 +310,16 @@ ftrace_print_flags_seq(struct trace_seq *p, const char *delim,
 
                 str = flag_array[i].name;
                 flags &= ~mask;
-                if (p->len && delim)
+                if (!first && delim)
                         trace_seq_puts(p, delim);
+                else
+                        first = 0;
                 trace_seq_puts(p, str);
         }
 
         /* check for left over flags */
         if (flags) {
-                if (p->len && delim)
+                if (!first && delim)
                         trace_seq_puts(p, delim);
                 trace_seq_printf(p, "0x%lx", flags);
         }
@@ -344,7 +346,7 @@ ftrace_print_symbols_seq(struct trace_seq *p, unsigned long val,
                 break;
         }
 
-        if (!p->len)
+        if (ret == (const char *)(p->buffer + p->len))
                 trace_seq_printf(p, "0x%lx", val);
                 
         trace_seq_putc(p, 0);
@@ -370,7 +372,7 @@ ftrace_print_symbols_seq_u64(struct trace_seq *p, unsigned long long val,
                 break;
         }
 
-        if (!p->len)
+        if (ret == (const char *)(p->buffer + p->len))
                 trace_seq_printf(p, "0x%llx", val);
 
         trace_seq_putc(p, 0);
diff --git a/kernel/trace/trace_syscalls.c b/kernel/trace/trace_syscalls.c
index cb654542c1a1..96fc73369099 100644
--- a/kernel/trace/trace_syscalls.c
+++ b/kernel/trace/trace_syscalls.c
@@ -17,9 +17,9 @@ static DECLARE_BITMAP(enabled_enter_syscalls, NR_syscalls);
 static DECLARE_BITMAP(enabled_exit_syscalls, NR_syscalls);
 
 static int syscall_enter_register(struct ftrace_event_call *event,
-                                 enum trace_reg type);
+                                 enum trace_reg type, void *data);
 static int syscall_exit_register(struct ftrace_event_call *event,
-                                 enum trace_reg type);
+                                 enum trace_reg type, void *data);
 
 static int syscall_enter_define_fields(struct ftrace_event_call *call);
 static int syscall_exit_define_fields(struct ftrace_event_call *call);
@@ -468,8 +468,8 @@ int __init init_ftrace_syscalls(void)
         unsigned long addr;
         int i;
 
-        syscalls_metadata = kzalloc(sizeof(*syscalls_metadata) *
-                                        NR_syscalls, GFP_KERNEL);
+        syscalls_metadata = kcalloc(NR_syscalls, sizeof(*syscalls_metadata),
+                                    GFP_KERNEL);
         if (!syscalls_metadata) {
                 WARN_ON(1);
                 return -ENOMEM;
@@ -649,7 +649,7 @@ void perf_sysexit_disable(struct ftrace_event_call *call)
 #endif /* CONFIG_PERF_EVENTS */
 
 static int syscall_enter_register(struct ftrace_event_call *event,
-                                 enum trace_reg type)
+                                 enum trace_reg type, void *data)
 {
         switch (type) {
         case TRACE_REG_REGISTER:
@@ -664,13 +664,18 @@ static int syscall_enter_register(struct ftrace_event_call *event,
         case TRACE_REG_PERF_UNREGISTER:
                 perf_sysenter_disable(event);
                 return 0;
+        case TRACE_REG_PERF_OPEN:
+        case TRACE_REG_PERF_CLOSE:
+        case TRACE_REG_PERF_ADD:
+        case TRACE_REG_PERF_DEL:
+                return 0;
 #endif
         }
         return 0;
 }
 
 static int syscall_exit_register(struct ftrace_event_call *event,
-                                 enum trace_reg type)
+                                 enum trace_reg type, void *data)
 {
         switch (type) {
         case TRACE_REG_REGISTER:
@@ -685,6 +690,11 @@ static int syscall_exit_register(struct ftrace_event_call *event,
         case TRACE_REG_PERF_UNREGISTER:
                 perf_sysexit_disable(event);
                 return 0;
+        case TRACE_REG_PERF_OPEN:
+        case TRACE_REG_PERF_CLOSE:
+        case TRACE_REG_PERF_ADD:
+        case TRACE_REG_PERF_DEL:
+                return 0;
 #endif
         }
         return 0;