Merge branch 'tip/perf/core-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace into perf/core

Pull tracing updates from Steven Rostedt.

Signed-off-by: Ingo Molnar <[e-mail]>

Documentation/kernel-parameters.txt

···
 			to facilitate early boot debugging.
 			See also Documentation/trace/events.txt
 
+	trace_options=[option-list]
+			[FTRACE] Enable or disable tracer options at boot.
+			The option-list is a comma delimited list of options
+			that can be enabled or disabled just as if you were
+			to echo the option name into
+
+			    /sys/kernel/debug/tracing/trace_options
+
+			For example, to enable stacktrace option (to dump the
+			stack trace of each event), add to the command line:
+
+			      trace_options=stacktrace
+
+			See also Documentation/trace/ftrace.txt "trace options"
+			section.
+
 	transparent_hugepage=
 			[KNL]
 			Format: [always|madvise|never]

include/linux/ftrace_event.h

···
 void trace_current_buffer_unlock_commit(struct ring_buffer *buffer,
 					struct ring_buffer_event *event,
 					unsigned long flags, int pc);
-void trace_nowake_buffer_unlock_commit(struct ring_buffer *buffer,
-				       struct ring_buffer_event *event,
-					unsigned long flags, int pc);
-void trace_nowake_buffer_unlock_commit_regs(struct ring_buffer *buffer,
-					    struct ring_buffer_event *event,
-					    unsigned long flags, int pc,
-					    struct pt_regs *regs);
+void trace_buffer_unlock_commit(struct ring_buffer *buffer,
+				struct ring_buffer_event *event,
+				unsigned long flags, int pc);
+void trace_buffer_unlock_commit_regs(struct ring_buffer *buffer,
+				     struct ring_buffer_event *event,
+				     unsigned long flags, int pc,
+				     struct pt_regs *regs);
 void trace_current_buffer_discard_commit(struct ring_buffer *buffer,
 					 struct ring_buffer_event *event);
 

include/linux/kernel.h

···
 
 extern void ftrace_dump(enum ftrace_dump_mode oops_dump_mode);
 #else
-static inline __printf(1, 2)
-int trace_printk(const char *fmt, ...);
-
 static inline void tracing_start(void) { }
 static inline void tracing_stop(void) { }
 static inline void ftrace_off_permanent(void) { }
···
 static inline void tracing_off(void) { }
 static inline int tracing_is_on(void) { return 0; }
 
-static inline int
-trace_printk(const char *fmt, ...)
+static inline __printf(1, 2)
+int trace_printk(const char *fmt, ...)
 {
 	return 0;
 }

include/linux/ring_buffer.h

···
 void ring_buffer_record_disable_cpu(struct ring_buffer *buffer, int cpu);
 void ring_buffer_record_enable_cpu(struct ring_buffer *buffer, int cpu);
 
-unsigned long ring_buffer_oldest_event_ts(struct ring_buffer *buffer, int cpu);
+u64 ring_buffer_oldest_event_ts(struct ring_buffer *buffer, int cpu);
 unsigned long ring_buffer_bytes_cpu(struct ring_buffer *buffer, int cpu);
 unsigned long ring_buffer_entries(struct ring_buffer *buffer);
 unsigned long ring_buffer_overruns(struct ring_buffer *buffer);
 unsigned long ring_buffer_entries_cpu(struct ring_buffer *buffer, int cpu);
 unsigned long ring_buffer_overrun_cpu(struct ring_buffer *buffer, int cpu);
 unsigned long ring_buffer_commit_overrun_cpu(struct ring_buffer *buffer, int cpu);
+unsigned long ring_buffer_dropped_events_cpu(struct ring_buffer *buffer, int cpu);
 
 u64 ring_buffer_time_stamp(struct ring_buffer *buffer, int cpu);
 void ring_buffer_normalize_time_stamp(struct ring_buffer *buffer,

include/trace/ftrace.h

···
 	{ assign; }							\
 									\
 	if (!filter_current_check_discard(buffer, event_call, entry, event)) \
-		trace_nowake_buffer_unlock_commit(buffer,		\
-						  event, irq_flags, pc); \
+		trace_buffer_unlock_commit(buffer, event, irq_flags, pc); \
 }
 /*
  * The ftrace_test_probe is compiled out, it is only here as a build time check

include/trace/syscall.h

···
 	struct ftrace_event_call *exit_event;
 };
 
-#ifdef CONFIG_FTRACE_SYSCALLS
-extern unsigned long arch_syscall_addr(int nr);
-extern int init_syscall_trace(struct ftrace_event_call *call);
-
-extern int reg_event_syscall_enter(struct ftrace_event_call *call);
-extern void unreg_event_syscall_enter(struct ftrace_event_call *call);
-extern int reg_event_syscall_exit(struct ftrace_event_call *call);
-extern void unreg_event_syscall_exit(struct ftrace_event_call *call);
-extern int
-ftrace_format_syscall(struct ftrace_event_call *call, struct trace_seq *s);
-enum print_line_t print_syscall_enter(struct trace_iterator *iter, int flags,
-				      struct trace_event *event);
-enum print_line_t print_syscall_exit(struct trace_iterator *iter, int flags,
-				     struct trace_event *event);
-#endif
-
-#ifdef CONFIG_PERF_EVENTS
-int perf_sysenter_enable(struct ftrace_event_call *call);
-void perf_sysenter_disable(struct ftrace_event_call *call);
-int perf_sysexit_enable(struct ftrace_event_call *call);
-void perf_sysexit_disable(struct ftrace_event_call *call);
-#endif
-
 #endif /* _TRACE_SYSCALL_H */

kernel/trace/Kconfig

···
 	select BINARY_PRINTF
 	select EVENT_TRACING
 	select TRACE_CLOCK
+	select IRQ_WORK
 
 config GENERIC_TRACER
 	bool

kernel/trace/ftrace.c

···
 {
 	return register_ftrace_command(&ftrace_mod_cmd);
 }
-device_initcall(ftrace_mod_cmd_init);
+core_initcall(ftrace_mod_cmd_init);
 
 static void function_trace_probe_call(unsigned long ip, unsigned long parent_ip,
 				      struct ftrace_ops *op, struct pt_regs *pt_regs)
···
 	ftrace_enabled = 1;
 	return 0;
 }
-device_initcall(ftrace_nodyn_init);
+core_initcall(ftrace_nodyn_init);
 
 static inline int ftrace_init_dyn_debugfs(struct dentry *d_tracer) { return 0; }
 static inline void ftrace_startup_enable(int command) { }
···
 	if (strlen(tmp) == 0)
 		return 1;
 
-	ret = strict_strtol(tmp, 10, &val);
+	ret = kstrtol(tmp, 10, &val);
 	if (ret < 0)
 		return ret;
 

kernel/trace/ring_buffer.c

···
 	unsigned long			lost_events;
 	unsigned long			last_overrun;
 	local_t				entries_bytes;
-	local_t				commit_overrun;
-	local_t				overrun;
 	local_t				entries;
+	local_t				overrun;
+	local_t				commit_overrun;
+	local_t				dropped_events;
 	local_t				committing;
 	local_t				commits;
 	unsigned long			read;
···
 }
 
 /**
- * ring_buffer_update_event - update event type and data
+ * rb_update_event - update event type and data
  * @event: the even to update
  * @type: the type of event
  * @length: the size of the event field in the ring buffer
···
 			 * If we are not in overwrite mode,
 			 * this is easy, just stop here.
 			 */
-			if (!(buffer->flags & RB_FL_OVERWRITE))
+			if (!(buffer->flags & RB_FL_OVERWRITE)) {
+				local_inc(&cpu_buffer->dropped_events);
 				goto out_reset;
+			}
 
 			ret = rb_handle_head_page(cpu_buffer,
 						  tail_page,
···
  * and not the length of the event which would hold the header.
  */
 int ring_buffer_write(struct ring_buffer *buffer,
-			unsigned long length,
-			void *data)
+		      unsigned long length,
+		      void *data)
 {
 	struct ring_buffer_per_cpu *cpu_buffer;
 	struct ring_buffer_event *event;
···
  * @buffer: The ring buffer
  * @cpu: The per CPU buffer to read from.
  */
-unsigned long ring_buffer_oldest_event_ts(struct ring_buffer *buffer, int cpu)
+u64 ring_buffer_oldest_event_ts(struct ring_buffer *buffer, int cpu)
 {
 	unsigned long flags;
 	struct ring_buffer_per_cpu *cpu_buffer;
 	struct buffer_page *bpage;
-	unsigned long ret;
+	u64 ret;
 
 	if (!cpumask_test_cpu(cpu, buffer->cpumask))
 		return 0;
···
 EXPORT_SYMBOL_GPL(ring_buffer_entries_cpu);
 
 /**
- * ring_buffer_overrun_cpu - get the number of overruns in a cpu_buffer
+ * ring_buffer_overrun_cpu - get the number of overruns caused by the ring
+ * buffer wrapping around (only if RB_FL_OVERWRITE is on).
  * @buffer: The ring buffer
  * @cpu: The per CPU buffer to get the number of overruns from
  */
···
 EXPORT_SYMBOL_GPL(ring_buffer_overrun_cpu);
 
 /**
- * ring_buffer_commit_overrun_cpu - get the number of overruns caused by commits
+ * ring_buffer_commit_overrun_cpu - get the number of overruns caused by
+ * commits failing due to the buffer wrapping around while there are uncommitted
+ * events, such as during an interrupt storm.
  * @buffer: The ring buffer
  * @cpu: The per CPU buffer to get the number of overruns from
  */
···
 	return ret;
 }
 EXPORT_SYMBOL_GPL(ring_buffer_commit_overrun_cpu);
+
+/**
+ * ring_buffer_dropped_events_cpu - get the number of dropped events caused by
+ * the ring buffer filling up (only if RB_FL_OVERWRITE is off).
+ * @buffer: The ring buffer
+ * @cpu: The per CPU buffer to get the number of overruns from
+ */
+unsigned long
+ring_buffer_dropped_events_cpu(struct ring_buffer *buffer, int cpu)
+{
+	struct ring_buffer_per_cpu *cpu_buffer;
+	unsigned long ret;
+
+	if (!cpumask_test_cpu(cpu, buffer->cpumask))
+		return 0;
+
+	cpu_buffer = buffer->buffers[cpu];
+	ret = local_read(&cpu_buffer->dropped_events);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(ring_buffer_dropped_events_cpu);
 
 /**
  * ring_buffer_entries - get the number of entries in a buffer
···
 	local_set(&cpu_buffer->reader_page->page->commit, 0);
 	cpu_buffer->reader_page->read = 0;
 
-	local_set(&cpu_buffer->commit_overrun, 0);
 	local_set(&cpu_buffer->entries_bytes, 0);
 	local_set(&cpu_buffer->overrun, 0);
+	local_set(&cpu_buffer->commit_overrun, 0);
+	local_set(&cpu_buffer->dropped_events, 0);
 	local_set(&cpu_buffer->entries, 0);
 	local_set(&cpu_buffer->committing, 0);
 	local_set(&cpu_buffer->commits, 0);

kernel/trace/trace.c

···
 #include <linux/seq_file.h>
 #include <linux/notifier.h>
 #include <linux/irqflags.h>
+#include <linux/irq_work.h>
 #include <linux/debugfs.h>
 #include <linux/pagemap.h>
 #include <linux/hardirq.h>
···
 {
 	return 0;
 }
+
+/*
+ * To prevent the comm cache from being overwritten when no
+ * tracing is active, only save the comm when a trace event
+ * occurred.
+ */
+static DEFINE_PER_CPU(bool, trace_cmdline_save);
+
+/*
+ * When a reader is waiting for data, then this variable is
+ * set to true.
+ */
+static bool trace_wakeup_needed;
+
+static struct irq_work trace_work_wakeup;
 
 /*
  * Kill all tracing for good (never come back).
···
 }
 __setup("ftrace_dump_on_oops", set_ftrace_dump_on_oops);
 
+
+static char trace_boot_options_buf[MAX_TRACER_SIZE] __initdata;
+static char *trace_boot_options __initdata;
+
+static int __init set_trace_boot_options(char *str)
+{
+	strncpy(trace_boot_options_buf, str, MAX_TRACER_SIZE);
+	trace_boot_options = trace_boot_options_buf;
+	return 0;
+}
+__setup("trace_options=", set_trace_boot_options);
+
 unsigned long long ns2usecs(cycle_t nsec)
 {
 	nsec += 500;
···
 
 static DEFINE_PER_CPU(struct trace_array_cpu, max_tr_data);
 
-/* tracer_enabled is used to toggle activation of a tracer */
-static int			tracer_enabled = 1;
-
-/**
- * tracing_is_enabled - return tracer_enabled status
- *
- * This function is used by other tracers to know the status
- * of the tracer_enabled flag.  Tracers may use this function
- * to know if it should enable their features when starting
- * up. See irqsoff tracer for an example (start_irqsoff_tracer).
- */
 int tracing_is_enabled(void)
 {
-	return tracer_enabled;
+	return tracing_is_on();
 }
 
 /*
···
 static int trace_stop_count;
 static DEFINE_RAW_SPINLOCK(tracing_start_lock);
 
-static void wakeup_work_handler(struct work_struct *work)
+/**
+ * trace_wake_up - wake up tasks waiting for trace input
+ *
+ * Schedules a delayed work to wake up any task that is blocked on the
+ * trace_wait queue. These is used with trace_poll for tasks polling the
+ * trace.
+ */
+static void trace_wake_up(struct irq_work *work)
 {
-	wake_up(&trace_wait);
-}
+	wake_up_all(&trace_wait);
 
-static DECLARE_DELAYED_WORK(wakeup_work, wakeup_work_handler);
+}
 
 /**
  * tracing_on - enable tracing buffers
···
 }
 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
- * trace_wait queue. These is used with trace_poll for tasks polling the
- * trace.
- */
-void trace_wake_up(void)
-{
-	const unsigned long delay = msecs_to_jiffies(2);
-
-	if (trace_flags & TRACE_ITER_BLOCK)
-		return;
-	schedule_delayed_work(&wakeup_work, delay);
-}
-
 static int __init set_buf_size(char *str)
 {
 	unsigned long buf_size;
···
 
 	if (!str)
 		return 0;
-	ret = strict_strtoul(str, 0, &threshold);
+	ret = kstrtoul(str, 0, &threshold);
 	if (ret < 0)
 		return 0;
 	tracing_thresh = threshold * 1000;
···
 }
 #endif /* CONFIG_TRACER_MAX_TRACE */
 
+static void default_wait_pipe(struct trace_iterator *iter)
+{
+	DEFINE_WAIT(wait);
+
+	prepare_to_wait(&trace_wait, &wait, TASK_INTERRUPTIBLE);
+
+	/*
+	 * The events can happen in critical sections where
+	 * checking a work queue can cause deadlocks.
+	 * After adding a task to the queue, this flag is set
+	 * only to notify events to try to wake up the queue
+	 * using irq_work.
+	 *
+	 * We don't clear it even if the buffer is no longer
+	 * empty. The flag only causes the next event to run
+	 * irq_work to do the work queue wake up. The worse
+	 * that can happen if we race with !trace_empty() is that
+	 * an event will cause an irq_work to try to wake up
+	 * an empty queue.
+	 *
+	 * There's no reason to protect this flag either, as
+	 * the work queue and irq_work logic will do the necessary
+	 * synchronization for the wake ups. The only thing
+	 * that is necessary is that the wake up happens after
+	 * a task has been queued. It's OK for spurious wake ups.
+	 */
+	trace_wakeup_needed = true;
+
+	if (trace_empty(iter))
+		schedule();
+
+	finish_wait(&trace_wait, &wait);
+}
+
 /**
  * register_tracer - register a tracer with the ftrace system.
  * @type - the plugin for the tracer
···
 
  out_unlock:
 	return ret;
-}
-
-void unregister_tracer(struct tracer *type)
-{
-	struct tracer **t;
-
-	mutex_lock(&trace_types_lock);
-	for (t = &trace_types; *t; t = &(*t)->next) {
-		if (*t == type)
-			goto found;
-	}
-	pr_info("Tracer %s not registered\n", type->name);
-	goto out;
-
- found:
-	*t = (*t)->next;
-
-	if (type == current_trace && tracer_enabled) {
-		tracer_enabled = 0;
-		tracing_stop();
-		if (current_trace->stop)
-			current_trace->stop(&global_trace);
-		current_trace = &nop_trace;
-	}
-out:
-	mutex_unlock(&trace_types_lock);
 }
 
 void tracing_reset(struct trace_array *tr, int cpu)
···
 
 void tracing_record_cmdline(struct task_struct *tsk)
 {
-	if (atomic_read(&trace_record_cmdline_disabled) || !tracer_enabled ||
-	    !tracing_is_on())
+	if (atomic_read(&trace_record_cmdline_disabled) || !tracing_is_on())
 		return;
+
+	if (!__this_cpu_read(trace_cmdline_save))
+		return;
+
+	__this_cpu_write(trace_cmdline_save, false);
 
 	trace_save_cmdline(tsk);
 }
···
 	return event;
 }
 
+void
+__buffer_unlock_commit(struct ring_buffer *buffer, struct ring_buffer_event *event)
+{
+	__this_cpu_write(trace_cmdline_save, true);
+	if (trace_wakeup_needed) {
+		trace_wakeup_needed = false;
+		/* irq_work_queue() supplies it's own memory barriers */
+		irq_work_queue(&trace_work_wakeup);
+	}
+	ring_buffer_unlock_commit(buffer, event);
+}
+
 static inline void
 __trace_buffer_unlock_commit(struct ring_buffer *buffer,
 			     struct ring_buffer_event *event,
-			     unsigned long flags, int pc,
-			     int wake)
+			     unsigned long flags, int pc)
 {
-	ring_buffer_unlock_commit(buffer, event);
+	__buffer_unlock_commit(buffer, event);
 
 	ftrace_trace_stack(buffer, flags, 6, pc);
 	ftrace_trace_userstack(buffer, flags, pc);
-
-	if (wake)
-		trace_wake_up();
 }
 
 void trace_buffer_unlock_commit(struct ring_buffer *buffer,
 				struct ring_buffer_event *event,
 				unsigned long flags, int pc)
 {
-	__trace_buffer_unlock_commit(buffer, event, flags, pc, 1);
+	__trace_buffer_unlock_commit(buffer, event, flags, pc);
 }
+EXPORT_SYMBOL_GPL(trace_buffer_unlock_commit);
 
 struct ring_buffer_event *
 trace_current_buffer_lock_reserve(struct ring_buffer **current_rb,
···
 					struct ring_buffer_event *event,
 					unsigned long flags, int pc)
 {
-	__trace_buffer_unlock_commit(buffer, event, flags, pc, 1);
+	__trace_buffer_unlock_commit(buffer, event, flags, pc);
 }
 EXPORT_SYMBOL_GPL(trace_current_buffer_unlock_commit);
 
-void trace_nowake_buffer_unlock_commit(struct ring_buffer *buffer,
-				       struct ring_buffer_event *event,
-				       unsigned long flags, int pc)
+void trace_buffer_unlock_commit_regs(struct ring_buffer *buffer,
+				     struct ring_buffer_event *event,
+				     unsigned long flags, int pc,
+				     struct pt_regs *regs)
 {
-	__trace_buffer_unlock_commit(buffer, event, flags, pc, 0);
-}
-EXPORT_SYMBOL_GPL(trace_nowake_buffer_unlock_commit);
-
-void trace_nowake_buffer_unlock_commit_regs(struct ring_buffer *buffer,
-					    struct ring_buffer_event *event,
-					    unsigned long flags, int pc,
-					    struct pt_regs *regs)
-{
-	ring_buffer_unlock_commit(buffer, event);
+	__buffer_unlock_commit(buffer, event);
 
 	ftrace_trace_stack_regs(buffer, flags, 0, pc, regs);
 	ftrace_trace_userstack(buffer, flags, pc);
 }
-EXPORT_SYMBOL_GPL(trace_nowake_buffer_unlock_commit_regs);
+EXPORT_SYMBOL_GPL(trace_buffer_unlock_commit_regs);
 
 void trace_current_buffer_discard_commit(struct ring_buffer *buffer,
 					 struct ring_buffer_event *event)
···
 	entry->parent_ip		= parent_ip;
 
 	if (!filter_check_discard(call, entry, buffer, event))
-		ring_buffer_unlock_commit(buffer, event);
+		__buffer_unlock_commit(buffer, event);
 }
 
 void
···
 	entry->size = trace.nr_entries;
 
 	if (!filter_check_discard(call, entry, buffer, event))
-		ring_buffer_unlock_commit(buffer, event);
+		__buffer_unlock_commit(buffer, event);
 
  out:
 	/* Again, don't let gcc optimize things here */
···
 
 	save_stack_trace_user(&trace);
 	if (!filter_check_discard(call, entry, buffer, event))
-		ring_buffer_unlock_commit(buffer, event);
+		__buffer_unlock_commit(buffer, event);
 
  out_drop_count:
 	__this_cpu_dec(user_stack_count);
···
 	return -ENOMEM;
 }
 
+static int buffers_allocated;
+
 void trace_printk_init_buffers(void)
 {
-	static int buffers_allocated;
-
 	if (buffers_allocated)
 		return;
 
···
 
 	pr_info("ftrace: Allocated trace_printk buffers\n");
 
+	/* Expand the buffers to set size */
+	tracing_update_buffers();
+
 	buffers_allocated = 1;
+
+	/*
+	 * trace_printk_init_buffers() can be called by modules.
+	 * If that happens, then we need to start cmdline recording
+	 * directly here. If the global_trace.buffer is already
+	 * allocated here, then this was called by module code.
+	 */
+	if (global_trace.buffer)
+		tracing_start_cmdline_record();
+}
+
+void trace_printk_start_comm(void)
+{
+	/* Start tracing comms if trace printk is set */
+	if (!buffers_allocated)
+		return;
+	tracing_start_cmdline_record();
+}
+
+static void trace_printk_start_stop_comm(int enabled)
+{
+	if (!buffers_allocated)
+		return;
+
+	if (enabled)
+		tracing_start_cmdline_record();
+	else
+		tracing_stop_cmdline_record();
 }
 
 /**
···
 
 	memcpy(entry->buf, tbuffer, sizeof(u32) * len);
 	if (!filter_check_discard(call, entry, buffer, event)) {
-		ring_buffer_unlock_commit(buffer, event);
+		__buffer_unlock_commit(buffer, event);
 		ftrace_trace_stack(buffer, flags, 6, pc);
 	}
 
···
 	memcpy(&entry->buf, tbuffer, len);
 	entry->buf[len] = '\0';
 	if (!filter_check_discard(call, entry, buffer, event)) {
-		ring_buffer_unlock_commit(buffer, event);
+		__buffer_unlock_commit(buffer, event);
 		ftrace_trace_stack(buffer, flags, 6, pc);
 	}
  out:
···
 
 	if (mask == TRACE_ITER_OVERWRITE)
 		ring_buffer_change_overwrite(global_trace.buffer, enabled);
+
+	if (mask == TRACE_ITER_PRINTK)
+		trace_printk_start_stop_comm(enabled);
 }
 
-static ssize_t
-tracing_trace_options_write(struct file *filp, const char __user *ubuf,
-			size_t cnt, loff_t *ppos)
+static int trace_set_options(char *option)
 {
-	char buf[64];
 	char *cmp;
 	int neg = 0;
-	int ret;
+	int ret = 0;
 	int i;
 
-	if (cnt >= sizeof(buf))
-		return -EINVAL;
-
-	if (copy_from_user(&buf, ubuf, cnt))
-		return -EFAULT;
-
-	buf[cnt] = 0;
-	cmp = strstrip(buf);
+	cmp = strstrip(option);
 
 	if (strncmp(cmp, "no", 2) == 0) {
 		neg = 1;
···
 		mutex_lock(&trace_types_lock);
 		ret = set_tracer_option(current_trace, cmp, neg);
 		mutex_unlock(&trace_types_lock);
-		if (ret)
-			return ret;
 	}
+
+	return ret;
+}
+
+static ssize_t
+tracing_trace_options_write(struct file *filp, const char __user *ubuf,
+			size_t cnt, loff_t *ppos)
+{
+	char buf[64];
+
+	if (cnt >= sizeof(buf))
+		return -EINVAL;
+
+	if (copy_from_user(&buf, ubuf, cnt))
+		return -EFAULT;
+
+	trace_set_options(buf);
 
 	*ppos += cnt;
 
···
 };
 
 static ssize_t
-tracing_ctrl_read(struct file *filp, char __user *ubuf,
-		  size_t cnt, loff_t *ppos)
-{
-	char buf[64];
-	int r;
-
-	r = sprintf(buf, "%u\n", tracer_enabled);
-	return simple_read_from_buffer(ubuf, cnt, ppos, buf, r);
-}
-
-static ssize_t
-tracing_ctrl_write(struct file *filp, const char __user *ubuf,
-		   size_t cnt, loff_t *ppos)
-{
-	struct trace_array *tr = filp->private_data;
-	unsigned long val;
-	int ret;
-
-	ret = kstrtoul_from_user(ubuf, cnt, 10, &val);
-	if (ret)
-		return ret;
-
-	val = !!val;
-
-	mutex_lock(&trace_types_lock);
-	if (tracer_enabled ^ val) {
-
-		/* Only need to warn if this is used to change the state */
-		WARN_ONCE(1, "tracing_enabled is deprecated. Use tracing_on");
-
-		if (val) {
-			tracer_enabled = 1;
-			if (current_trace->start)
-				current_trace->start(tr);
-			tracing_start();
-		} else {
-			tracer_enabled = 0;
-			tracing_stop();
-			if (current_trace->stop)
-				current_trace->stop(tr);
-		}
-	}
-	mutex_unlock(&trace_types_lock);
-
-	*ppos += cnt;
-
-	return cnt;
-}
-
-static ssize_t
 tracing_set_trace_read(struct file *filp, char __user *ubuf,
 		       size_t cnt, loff_t *ppos)
 {
···
 	 * expanding it later.
 	 */
 	ring_buffer_expanded = 1;
+
+	/* May be called before buffers are initialized */
+	if (!global_trace.buffer)
+		return 0;
 
 	ret = ring_buffer_resize(global_trace.buffer, size, cpu);
 	if (ret < 0)
···
 	}
 }
 
-
-void default_wait_pipe(struct trace_iterator *iter)
-{
-	DEFINE_WAIT(wait);
-
-	prepare_to_wait(&trace_wait, &wait, TASK_INTERRUPTIBLE);
-
-	if (trace_empty(iter))
-		schedule();
-
-	finish_wait(&trace_wait, &wait);
-}
-
 /*
  * This is a make-shift waitqueue.
  * A tracer might use this callback on some rare cases:
···
 			return -EINTR;
 
 		/*
-		 * We block until we read something and tracing is disabled.
+		 * We block until we read something and tracing is enabled.
 		 * We still block if tracing is disabled, but we have never
 		 * read anything. This allows a user to cat this file, and
 		 * then enable tracing. But after we have read something,
···
 		 *
 		 * iter->pos will be 0 if we haven't read anything.
 		 */
-		if (!tracer_enabled && iter->pos)
+		if (tracing_is_enabled() && iter->pos)
 			break;
 	}
 
···
 	} else
 		entry->buf[cnt] = '\0';
 
-	ring_buffer_unlock_commit(buffer, event);
+	__buffer_unlock_commit(buffer, event);
 
 	written = cnt;
 
···
 	if (max_tr.buffer)
 		ring_buffer_set_clock(max_tr.buffer, trace_clocks[i].func);
 
+	/*
+	 * New clock may not be consistent with the previous clock.
+	 * Reset the buffer so that it doesn't have incomparable timestamps.
+	 */
+	tracing_reset_online_cpus(&global_trace);
+	if (max_tr.buffer)
+		tracing_reset_online_cpus(&max_tr);
+
 	mutex_unlock(&trace_types_lock);
 
 	*fpos += cnt;
···
 	.open		= tracing_open_generic,
 	.read		= tracing_max_lat_read,
 	.write		= tracing_max_lat_write,
-	.llseek		= generic_file_llseek,
-};
-
-static const struct file_operations tracing_ctrl_fops = {
-	.open		= tracing_open_generic,
-	.read		= tracing_ctrl_read,
-	.write		= tracing_ctrl_write,
 	.llseek		= generic_file_llseek,
 };
 
···
 	t = ns2usecs(ring_buffer_time_stamp(tr->buffer, cpu));
 	usec_rem = do_div(t, USEC_PER_SEC);
 	trace_seq_printf(s, "now ts: %5llu.%06lu\n", t, usec_rem);
+
+	cnt = ring_buffer_dropped_events_cpu(tr->buffer, cpu);
+	trace_seq_printf(s, "dropped events: %ld\n", cnt);
 
 	count = simple_read_from_buffer(ubuf, count, ppos, s->buffer, s->len);
 
···
 
 	d_tracer = tracing_init_dentry();
 
-	trace_create_file("tracing_enabled", 0644, d_tracer,
-			&global_trace, &tracing_ctrl_fops);
-
 	trace_create_file("trace_options", 0644, d_tracer,
 			NULL, &tracing_iter_fops);
 
···
 
 	/* Only allocate trace_printk buffers if a trace_printk exists */
 	if (__stop___trace_bprintk_fmt != __start___trace_bprintk_fmt)
+		/* Must be called before global_trace.buffer is allocated */
 		trace_printk_init_buffers();
 
 	/* To save memory, keep the ring buffer size to its minimum */
···
 #endif
 
 	trace_init_cmdlines();
+	init_irq_work(&trace_work_wakeup, trace_wake_up);
 
 	register_tracer(&nop_trace);
 	current_trace = &nop_trace;
···
 				       &trace_panic_notifier);
 
 	register_die_notifier(&trace_die_notifier);
+
+	while (trace_boot_options) {
+		char *option;
+
+		option = strsep(&trace_boot_options, ",");
+		trace_set_options(option);
+	}
 
 	return 0;
 

kernel/trace/trace.h

···
 	int			(*set_flag)(u32 old_flags, u32 bit, int set);
 	struct tracer		*next;
 	struct tracer_flags	*flags;
-	int			print_max;
-	int			use_max_tr;
+	bool			print_max;
+	bool			use_max_tr;
 };
 
 
···
 
 int tracer_init(struct tracer *t, struct trace_array *tr);
 int tracing_is_enabled(void);
-void trace_wake_up(void);
 void tracing_reset(struct trace_array *tr, int cpu);
 void tracing_reset_online_cpus(struct trace_array *tr);
 void tracing_reset_current(int cpu);
···
 			  unsigned long len,
 			  unsigned long flags,
 			  int pc);
-void trace_buffer_unlock_commit(struct ring_buffer *buffer,
-				struct ring_buffer_event *event,
-				unsigned long flags, int pc);
 
 struct trace_entry *tracing_get_trace_entry(struct trace_array *tr,
 						struct trace_array_cpu *data);
 
 struct trace_entry *trace_find_next_entry(struct trace_iterator *iter,
 					  int *ent_cpu, u64 *ent_ts);
+
+void __buffer_unlock_commit(struct ring_buffer *buffer,
+			    struct ring_buffer_event *event);
 
 int trace_empty(struct trace_iterator *iter);
 
···
 
 void tracing_iter_reset(struct trace_iterator *iter, int cpu);
 
-void default_wait_pipe(struct trace_iterator *iter);
 void poll_wait_pipe(struct trace_iterator *iter);
 
 void ftrace(struct trace_array *tr,
···
 void tracing_stop_sched_switch_record(void);
 void tracing_start_sched_switch_record(void);
 int register_tracer(struct tracer *type);
-void unregister_tracer(struct tracer *type);
 int is_tracing_stopped(void);
 enum trace_file_type {
 	TRACE_FILE_LAT_FMT	= 1,
···
 extern const char *__stop___trace_bprintk_fmt[];
 
 void trace_printk_init_buffers(void);
+void trace_printk_start_comm(void);
 
 #undef FTRACE_ENTRY
 #define FTRACE_ENTRY(call, struct_name, id, tstruct, print, filter)	\

kernel/trace/trace_branch.c

···
 	entry->correct = val == expect;
 
 	if (!filter_check_discard(call, entry, buffer, event))
-		ring_buffer_unlock_commit(buffer, event);
+		__buffer_unlock_commit(buffer, event);
 
  out:
 	atomic_dec(&tr->data[cpu]->disabled);
···
 	}
 	return register_tracer(&branch_trace);
 }
-device_initcall(init_branch_tracer);
+core_initcall(init_branch_tracer);
 
 #else
 static inline

kernel/trace/trace_events.c

···
 	mutex_unlock(&event_mutex);
 }
 
-static int
-ftrace_event_seq_open(struct inode *inode, struct file *file)
-{
-	const struct seq_operations *seq_ops;
-
-	if ((file->f_mode & FMODE_WRITE) &&
-	    (file->f_flags & O_TRUNC))
-		ftrace_clear_events();
-
-	seq_ops = inode->i_private;
-	return seq_open(file, seq_ops);
-}
-
 static ssize_t
 event_enable_read(struct file *filp, char __user *ubuf, size_t cnt,
 		  loff_t *ppos)
···
 	return r;
 }
 
+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 const struct seq_operations show_event_seq_ops = {
 	.start = t_start,
 	.next = t_next,
···
 };
 
 static const struct file_operations ftrace_avail_fops = {
-	.open = ftrace_event_seq_open,
+	.open = ftrace_event_avail_open,
 	.read = seq_read,
 	.llseek = seq_lseek,
 	.release = seq_release,
 };
 
 static const struct file_operations ftrace_set_event_fops = {
-	.open = ftrace_event_seq_open,
+	.open = ftrace_event_set_open,
 	.read = seq_read,
 	.write = ftrace_event_write,
 	.llseek = seq_lseek,
···
 			   "'events' directory\n");
 
 	return d_events;
+}
+
+static int
+ftrace_event_avail_open(struct inode *inode, struct file *file)
+{
+	const struct seq_operations *seq_ops = &show_event_seq_ops;
+
+	return seq_open(file, seq_ops);
+}
+
+static int
+ftrace_event_set_open(struct inode *inode, struct file *file)
+{
+	const struct seq_operations *seq_ops = &show_set_event_seq_ops;
+
+	if ((file->f_mode & FMODE_WRITE) &&
+	    (file->f_flags & O_TRUNC))
+		ftrace_clear_events();
+
+	return seq_open(file, seq_ops);
 }
 
 static struct dentry *
···
 		if (ret)
 			pr_warn("Failed to enable trace event: %s\n", token);
 	}
+
+	trace_printk_start_comm();
+
 	return 0;
 }
 
···
 		return 0;
 
 	entry = debugfs_create_file("available_events", 0444, d_tracer,
-				    (void *)&show_event_seq_ops,
-				    &ftrace_avail_fops);
+				    NULL, &ftrace_avail_fops);
 	if (!entry)
 		pr_warning("Could not create debugfs "
 			   "'available_events' entry\n");
 
 	entry = debugfs_create_file("set_event", 0644, d_tracer,
-				    (void *)&show_set_event_seq_ops,
-				    &ftrace_set_event_fops);
+				    NULL, &ftrace_set_event_fops);
 	if (!entry)
 		pr_warning("Could not create debugfs "
 			   "'set_event' entry\n");
···
 	entry->ip			= ip;
 	entry->parent_ip		= parent_ip;
 
-	trace_nowake_buffer_unlock_commit(buffer, event, flags, pc);
+	trace_buffer_unlock_commit(buffer, event, flags, pc);
 
  out:
 	atomic_dec(&per_cpu(ftrace_test_event_disable, cpu));

kernel/trace/trace_events_filter.c

···
 		}
 	} else {
 		if (field->is_signed)
-			ret = strict_strtoll(pred->regex.pattern, 0, &val);
+			ret = kstrtoll(pred->regex.pattern, 0, &val);
 		else
-			ret = strict_strtoull(pred->regex.pattern, 0, &val);
+			ret = kstrtoull(pred->regex.pattern, 0, &val);
 		if (ret) {
 			parse_error(ps, FILT_ERR_ILLEGAL_INTVAL, 0);
 			return -EINVAL;

kernel/trace/trace_functions.c

···
 	 * We use the callback data field (which is a pointer)
 	 * as our counter.
 	 */
-	ret = strict_strtoul(number, 0, (unsigned long *)&count);
+	ret = kstrtoul(number, 0, (unsigned long *)&count);
 	if (ret)
 		return ret;
 
···
 	init_func_cmd_traceon();
 	return register_tracer(&function_trace);
 }
-device_initcall(init_function_trace);
-
+core_initcall(init_function_trace);

kernel/trace/trace_functions_graph.c

···
 	entry	= ring_buffer_event_data(event);
 	entry->graph_ent			= *trace;
 	if (!filter_current_check_discard(buffer, call, entry, event))
-		ring_buffer_unlock_commit(buffer, event);
+		__buffer_unlock_commit(buffer, event);
 
 	return 1;
 }
···
 	entry	= ring_buffer_event_data(event);
 	entry->ret				= *trace;
 	if (!filter_current_check_discard(buffer, call, entry, event))
-		ring_buffer_unlock_commit(buffer, event);
+		__buffer_unlock_commit(buffer, event);
 }
 
 void trace_graph_return(struct ftrace_graph_ret *trace)
···
 	return register_tracer(&graph_trace);
 }
 
-device_initcall(init_graph_trace);
+core_initcall(init_graph_trace);

kernel/trace/trace_irqsoff.c

···
 	.reset		= irqsoff_tracer_reset,
 	.start		= irqsoff_tracer_start,
 	.stop		= irqsoff_tracer_stop,
-	.print_max	= 1,
+	.print_max	= true,
 	.print_header   = irqsoff_print_header,
 	.print_line     = irqsoff_print_line,
 	.flags		= &tracer_flags,
···
 #endif
 	.open           = irqsoff_trace_open,
 	.close          = irqsoff_trace_close,
-	.use_max_tr	= 1,
+	.use_max_tr	= true,
 };
 # define register_irqsoff(trace) register_tracer(&trace)
 #else
···
 	.reset		= irqsoff_tracer_reset,
 	.start		= irqsoff_tracer_start,
 	.stop		= irqsoff_tracer_stop,
-	.print_max	= 1,
+	.print_max	= true,
 	.print_header   = irqsoff_print_header,
 	.print_line     = irqsoff_print_line,
 	.flags		= &tracer_flags,
···
 #endif
 	.open		= irqsoff_trace_open,
 	.close		= irqsoff_trace_close,
-	.use_max_tr	= 1,
+	.use_max_tr	= true,
 };
 # define register_preemptoff(trace) register_tracer(&trace)
 #else
···
 	.reset		= irqsoff_tracer_reset,
 	.start		= irqsoff_tracer_start,
 	.stop		= irqsoff_tracer_stop,
-	.print_max	= 1,
+	.print_max	= true,
 	.print_header   = irqsoff_print_header,
 	.print_line     = irqsoff_print_line,
 	.flags		= &tracer_flags,
···
 #endif
 	.open		= irqsoff_trace_open,
 	.close		= irqsoff_trace_close,
-	.use_max_tr	= 1,
+	.use_max_tr	= true,
 };
 
 # define register_preemptirqsoff(trace) register_tracer(&trace)
···
 
 	return 0;
 }
-device_initcall(init_irqsoff_tracer);
+core_initcall(init_irqsoff_tracer);

kernel/trace/trace_kprobe.c

···
 			return -EINVAL;
 		}
 		/* an address specified */
-		ret = strict_strtoul(&argv[1][0], 0, (unsigned long *)&addr);
+		ret = kstrtoul(&argv[1][0], 0, (unsigned long *)&addr);
 		if (ret) {
 			pr_info("Failed to parse address.\n");
 			return ret;
···
 	store_trace_args(sizeof(*entry), tp, regs, (u8 *)&entry[1], dsize);
 
 	if (!filter_current_check_discard(buffer, call, entry, event))
-		trace_nowake_buffer_unlock_commit_regs(buffer, event,
-						       irq_flags, pc, regs);
+		trace_buffer_unlock_commit_regs(buffer, event,
+						irq_flags, pc, regs);
 }
 
 /* Kretprobe handler */
···
 	store_trace_args(sizeof(*entry), tp, regs, (u8 *)&entry[1], dsize);
 
 	if (!filter_current_check_discard(buffer, call, entry, event))
-		trace_nowake_buffer_unlock_commit_regs(buffer, event,
-						       irq_flags, pc, regs);
+		trace_buffer_unlock_commit_regs(buffer, event,
+						irq_flags, pc, regs);
 }
 
 /* Event entry printers */

kernel/trace/trace_probe.c

···
 			goto fail;
 
 		type++;
-		if (strict_strtoul(type, 0, &bs))
+		if (kstrtoul(type, 0, &bs))
 			goto fail;
 
 		switch (bs) {
···
 
 	tmp = strchr(symbol, '+');
 	if (tmp) {
-		/* skip sign because strict_strtol doesn't accept '+' */
-		ret = strict_strtoul(tmp + 1, 0, offset);
+		/* skip sign because kstrtoul doesn't accept '+' */
+		ret = kstrtoul(tmp + 1, 0, offset);
 		if (ret)
 			return ret;
 
···
 			else
 				ret = -EINVAL;
 		} else if (isdigit(arg[5])) {
-			ret = strict_strtoul(arg + 5, 10, &param);
+			ret = kstrtoul(arg + 5, 10, &param);
 			if (ret || param > PARAM_MAX_STACK)
 				ret = -EINVAL;
 			else {
···
 
 	case '@':	/* memory or symbol */
 		if (isdigit(arg[1])) {
-			ret = strict_strtoul(arg + 1, 0, &param);
+			ret = kstrtoul(arg + 1, 0, &param);
 			if (ret)
 				break;
 
···
 		break;
 
 	case '+':	/* deref memory */
-		arg++;	/* Skip '+', because strict_strtol() rejects it. */
+		arg++;	/* Skip '+', because kstrtol() rejects it. */
 	case '-':
 		tmp = strchr(arg, '(');
 		if (!tmp)
 			break;
 
 		*tmp = '\0';
-		ret = strict_strtol(arg, 0, &offset);
+		ret = kstrtol(arg, 0, &offset);
 
 		if (ret)
 			break;

kernel/trace/trace_sched_switch.c

···
 	entry->next_cpu			= task_cpu(wakee);
 
 	if (!filter_check_discard(call, entry, buffer, event))
-		ring_buffer_unlock_commit(buffer, event);
-	ftrace_trace_stack(tr->buffer, flags, 6, pc);
-	ftrace_trace_userstack(tr->buffer, flags, pc);
+		trace_buffer_unlock_commit(buffer, event, flags, pc);
 }
 
 static void

kernel/trace/trace_sched_wakeup.c

···
 	.reset		= wakeup_tracer_reset,
 	.start		= wakeup_tracer_start,
 	.stop		= wakeup_tracer_stop,
-	.print_max	= 1,
+	.print_max	= true,
 	.print_header	= wakeup_print_header,
 	.print_line	= wakeup_print_line,
 	.flags		= &tracer_flags,
···
 #endif
 	.open		= wakeup_trace_open,
 	.close		= wakeup_trace_close,
-	.use_max_tr	= 1,
+	.use_max_tr	= true,
 };
 
 static struct tracer wakeup_rt_tracer __read_mostly =
···
 	.start		= wakeup_tracer_start,
 	.stop		= wakeup_tracer_stop,
 	.wait_pipe	= poll_wait_pipe,
-	.print_max	= 1,
+	.print_max	= true,
 	.print_header	= wakeup_print_header,
 	.print_line	= wakeup_print_line,
 	.flags		= &tracer_flags,
···
 #endif
 	.open		= wakeup_trace_open,
 	.close		= wakeup_trace_close,
-	.use_max_tr	= 1,
+	.use_max_tr	= true,
 };
 
 __init static int init_wakeup_tracer(void)
···
 
 	return 0;
 }
-device_initcall(init_wakeup_tracer);
+core_initcall(init_wakeup_tracer);

kernel/trace/trace_selftest.c

···
 					   int (*func)(void))
 {
 	int save_ftrace_enabled = ftrace_enabled;
-	int save_tracer_enabled = tracer_enabled;
 	unsigned long count;
 	char *func_name;
 	int ret;
···
 
 	/* enable tracing, and record the filter function */
 	ftrace_enabled = 1;
-	tracer_enabled = 1;
 
 	/* passed in by parameter to fool gcc from optimizing */
 	func();
···
 
  out:
 	ftrace_enabled = save_ftrace_enabled;
-	tracer_enabled = save_tracer_enabled;
 
 	/* Enable tracing on all functions again */
 	ftrace_set_global_filter(NULL, 0, 1);
···
 trace_selftest_function_recursion(void)
 {
 	int save_ftrace_enabled = ftrace_enabled;
-	int save_tracer_enabled = tracer_enabled;
 	char *func_name;
 	int len;
 	int ret;
···
 
 	/* enable tracing, and record the filter function */
 	ftrace_enabled = 1;
-	tracer_enabled = 1;
 
 	/* Handle PPC64 '.' name */
 	func_name = "*" __stringify(DYN_FTRACE_TEST_NAME);
···
 	ret = 0;
 out:
 	ftrace_enabled = save_ftrace_enabled;
-	tracer_enabled = save_tracer_enabled;
 
 	return ret;
 }
···
 trace_selftest_function_regs(void)
 {
 	int save_ftrace_enabled = ftrace_enabled;
-	int save_tracer_enabled = tracer_enabled;
 	char *func_name;
 	int len;
 	int ret;
···
 
 	/* enable tracing, and record the filter function */
 	ftrace_enabled = 1;
-	tracer_enabled = 1;
 
 	/* Handle PPC64 '.' name */
 	func_name = "*" __stringify(DYN_FTRACE_TEST_NAME);
···
 	ret = 0;
 out:
 	ftrace_enabled = save_ftrace_enabled;
-	tracer_enabled = save_tracer_enabled;
 
 	return ret;
 }
···
 trace_selftest_startup_function(struct tracer *trace, struct trace_array *tr)
 {
 	int save_ftrace_enabled = ftrace_enabled;
-	int save_tracer_enabled = tracer_enabled;
 	unsigned long count;
 	int ret;
 
···
 
 	/* start the tracing */
 	ftrace_enabled = 1;
-	tracer_enabled = 1;
 
 	ret = tracer_init(trace, tr);
 	if (ret) {
···
 	ret = trace_selftest_function_regs();
  out:
 	ftrace_enabled = save_ftrace_enabled;
-	tracer_enabled = save_tracer_enabled;
 
 	/* kill ftrace totally if we failed */
 	if (ret)
···
 	tracing_stop();
 	/* check both trace buffers */
 	ret = trace_test_buffer(tr, NULL);
+	printk("ret = %d\n", ret);
 	if (!ret)
 		ret = trace_test_buffer(&max_tr, &count);
 

kernel/trace/trace_syscalls.c

···
 static int syscall_exit_register(struct ftrace_event_call *event,
 				 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);
-
 static struct list_head *
 syscall_get_enter_fields(struct ftrace_event_call *call)
 {
···
 
 	return &entry->enter_fields;
 }
-
-struct trace_event_functions enter_syscall_print_funcs = {
-	.trace		= print_syscall_enter,
-};
-
-struct trace_event_functions exit_syscall_print_funcs = {
-	.trace		= print_syscall_exit,
-};
-
-struct ftrace_event_class event_class_syscall_enter = {
-	.system		= "syscalls",
-	.reg		= syscall_enter_register,
-	.define_fields	= syscall_enter_define_fields,
-	.get_fields	= syscall_get_enter_fields,
-	.raw_init	= init_syscall_trace,
-};
-
-struct ftrace_event_class event_class_syscall_exit = {
-	.system		= "syscalls",
-	.reg		= syscall_exit_register,
-	.define_fields	= syscall_exit_define_fields,
-	.fields		= LIST_HEAD_INIT(event_class_syscall_exit.fields),
-	.raw_init	= init_syscall_trace,
-};
 
 extern struct syscall_metadata *__start_syscalls_metadata[];
 extern struct syscall_metadata *__stop_syscalls_metadata[];
···
 	mutex_unlock(&syscall_trace_lock);
 }
 
-int init_syscall_trace(struct ftrace_event_call *call)
+static int init_syscall_trace(struct ftrace_event_call *call)
 {
 	int id;
 	int num;
···
 
 	return id;
 }
+
+struct trace_event_functions enter_syscall_print_funcs = {
+	.trace		= print_syscall_enter,
+};
+
+struct trace_event_functions exit_syscall_print_funcs = {
+	.trace		= print_syscall_exit,
+};
+
+struct ftrace_event_class event_class_syscall_enter = {
+	.system		= "syscalls",
+	.reg		= syscall_enter_register,
+	.define_fields	= syscall_enter_define_fields,
+	.get_fields	= syscall_get_enter_fields,
+	.raw_init	= init_syscall_trace,
+};
+
+struct ftrace_event_class event_class_syscall_exit = {
+	.system		= "syscalls",
+	.reg		= syscall_exit_register,
+	.define_fields	= syscall_exit_define_fields,
+	.fields		= LIST_HEAD_INIT(event_class_syscall_exit.fields),
+	.raw_init	= init_syscall_trace,
+};
 
 unsigned long __init __weak arch_syscall_addr(int nr)
 {
···
 	perf_trace_buf_submit(rec, size, rctx, 0, 1, regs, head, NULL);
 }
 
-int perf_sysenter_enable(struct ftrace_event_call *call)
+static int perf_sysenter_enable(struct ftrace_event_call *call)
 {
 	int ret = 0;
 	int num;
···
 	return ret;
 }
 
-void perf_sysenter_disable(struct ftrace_event_call *call)
+static void perf_sysenter_disable(struct ftrace_event_call *call)
 {
 	int num;
 
···
 	perf_trace_buf_submit(rec, size, rctx, 0, 1, regs, head, NULL);
 }
 
-int perf_sysexit_enable(struct ftrace_event_call *call)
+static int perf_sysexit_enable(struct ftrace_event_call *call)
 {
 	int ret = 0;
 	int num;
···
 	return ret;
 }
 
-void perf_sysexit_disable(struct ftrace_event_call *call)
+static void perf_sysexit_disable(struct ftrace_event_call *call)
 {
 	int num;
 

kernel/trace/trace_uprobe.c

···
 	if (ret)
 		goto fail_address_parse;
 
-	ret = strict_strtoul(arg, 0, &offset);
+	ret = kstrtoul(arg, 0, &offset);
 	if (ret)
 		goto fail_address_parse;