Merge tag 'trace-v4.4' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracking updates from Steven Rostedt:
 "Most of the changes are clean ups and small fixes.  Some of them have
  stable tags to them.  I searched through my INBOX just as the merge
  window opened and found lots of patches to pull.  I ran them through
  all my tests and they were in linux-next for a few days.

  Features added this release:
  ----------------------------

   - Module globbing.  You can now filter function tracing to several
     modules.  # echo '*:mod:*snd*' > set_ftrace_filter (Dmitry Safonov)

   - Tracer specific options are now visible even when the tracer is not
     active.  It was rather annoying that you can only see and modify
     tracer options after enabling the tracer.  Now they are in the
     options/ directory even when the tracer is not active.  Although
     they are still only visible when the tracer is active in the
     trace_options file.

   - Trace options are now per instance (although some of the tracer
     specific options are global)

   - New tracefs file: set_event_pid.  If any pid is added to this file,
     then all events in the instance will filter out events that are not
     part of this pid.  sched_switch and sched_wakeup events handle next
     and the wakee pids"

* tag 'trace-v4.4' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (68 commits)
  tracefs: Fix refcount imbalance in start_creating()
  tracing: Put back comma for empty fields in boot string parsing
  tracing: Apply tracer specific options from kernel command line.
  tracing: Add some documentation about set_event_pid
  ring_buffer: Remove unneeded smp_wmb() before wakeup of reader benchmark
  tracing: Allow dumping traces without tracking trace started cpus
  ring_buffer: Fix more races when terminating the producer in the benchmark
  ring_buffer: Do no not complete benchmark reader too early
  tracing: Remove redundant TP_ARGS redefining
  tracing: Rename max_stack_lock to stack_trace_max_lock
  tracing: Allow arch-specific stack tracer
  recordmcount: arm64: Replace the ignored mcount call into nop
  recordmcount: Fix endianness handling bug for nop_mcount
  tracepoints: Fix documentation of RCU lockdep checks
  tracing: ftrace_event_is_function() can return boolean
  tracing: is_legal_op() can return boolean
  ring-buffer: rb_event_is_commit() can return boolean
  ring-buffer: rb_per_cpu_empty() can return boolean
  ring_buffer: ring_buffer_empty{cpu}() can return boolean
  ring-buffer: rb_is_reader_page() can return boolean
  ...

1 files changed, 59 insertions, 61 deletions

diff --git a/kernel/trace/trace_sched_wakeup.c b/kernel/trace/trace_sched_wakeup.c
index 4bcfbac..9d4399b 100644
--- a/kernel/trace/trace_sched_wakeup.c
+++ b/kernel/trace/trace_sched_wakeup.c
@@ -34,31 +34,28 @@ static arch_spinlock_t wakeup_lock =
 
 static void wakeup_reset(struct trace_array *tr);
 static void __wakeup_reset(struct trace_array *tr);
-static int wakeup_graph_entry(struct ftrace_graph_ent *trace);
-static void wakeup_graph_return(struct ftrace_graph_ret *trace);
 
 static int save_flags;
-static bool function_enabled;
-
-#define TRACE_DISPLAY_GRAPH     1
 
-static struct tracer_opt trace_opts[] = {
 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
-	/* display latency trace as call graph */
-	{ TRACER_OPT(display-graph, TRACE_DISPLAY_GRAPH) },
+static int wakeup_display_graph(struct trace_array *tr, int set);
+# define is_graph(tr) ((tr)->trace_flags & TRACE_ITER_DISPLAY_GRAPH)
+#else
+static inline int wakeup_display_graph(struct trace_array *tr, int set)
+{
+	return 0;
+}
+# define is_graph(tr) false
 #endif
-	{ } /* Empty entry */
-};
-
-static struct tracer_flags tracer_flags = {
-	.val  = 0,
-	.opts = trace_opts,
-};
 
-#define is_graph() (tracer_flags.val & TRACE_DISPLAY_GRAPH)
 
 #ifdef CONFIG_FUNCTION_TRACER
 
+static int wakeup_graph_entry(struct ftrace_graph_ent *trace);
+static void wakeup_graph_return(struct ftrace_graph_ret *trace);
+
+static bool function_enabled;
+
 /*
  * Prologue for the wakeup function tracers.
  *
@@ -128,14 +125,13 @@ wakeup_tracer_call(unsigned long ip, unsigned long parent_ip,
 	atomic_dec(&data->disabled);
 	preempt_enable_notrace();
 }
-#endif /* CONFIG_FUNCTION_TRACER */
 
 static int register_wakeup_function(struct trace_array *tr, int graph, int set)
 {
 	int ret;
 
 	/* 'set' is set if TRACE_ITER_FUNCTION is about to be set */
-	if (function_enabled || (!set && !(trace_flags & TRACE_ITER_FUNCTION)))
+	if (function_enabled || (!set && !(tr->trace_flags & TRACE_ITER_FUNCTION)))
 		return 0;
 
 	if (graph)
@@ -163,20 +159,40 @@ static void unregister_wakeup_function(struct trace_array *tr, int graph)
 	function_enabled = false;
 }
 
-static void wakeup_function_set(struct trace_array *tr, int set)
+static int wakeup_function_set(struct trace_array *tr, u32 mask, int set)
 {
+	if (!(mask & TRACE_ITER_FUNCTION))
+		return 0;
+
 	if (set)
-		register_wakeup_function(tr, is_graph(), 1);
+		register_wakeup_function(tr, is_graph(tr), 1);
 	else
-		unregister_wakeup_function(tr, is_graph());
+		unregister_wakeup_function(tr, is_graph(tr));
+	return 1;
+}
+#else
+static int register_wakeup_function(struct trace_array *tr, int graph, int set)
+{
+	return 0;
+}
+static void unregister_wakeup_function(struct trace_array *tr, int graph) { }
+static int wakeup_function_set(struct trace_array *tr, u32 mask, int set)
+{
+	return 0;
 }
+#endif /* CONFIG_FUNCTION_TRACER */
 
 static int wakeup_flag_changed(struct trace_array *tr, u32 mask, int set)
 {
 	struct tracer *tracer = tr->current_trace;
 
-	if (mask & TRACE_ITER_FUNCTION)
-		wakeup_function_set(tr, set);
+	if (wakeup_function_set(tr, mask, set))
+		return 0;
+
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+	if (mask & TRACE_ITER_DISPLAY_GRAPH)
+		return wakeup_display_graph(tr, set);
+#endif
 
 	return trace_keep_overwrite(tracer, mask, set);
 }
@@ -203,14 +219,9 @@ static void stop_func_tracer(struct trace_array *tr, int graph)
 }
 
 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
-static int
-wakeup_set_flag(struct trace_array *tr, u32 old_flags, u32 bit, int set)
+static int wakeup_display_graph(struct trace_array *tr, int set)
 {
-
-	if (!(bit & TRACE_DISPLAY_GRAPH))
-		return -EINVAL;
-
-	if (!(is_graph() ^ set))
+	if (!(is_graph(tr) ^ set))
 		return 0;
 
 	stop_func_tracer(tr, !set);
@@ -259,7 +270,7 @@ static void wakeup_graph_return(struct ftrace_graph_ret *trace)
 
 static void wakeup_trace_open(struct trace_iterator *iter)
 {
-	if (is_graph())
+	if (is_graph(iter->tr))
 		graph_trace_open(iter);
 }
 
@@ -279,7 +290,7 @@ static enum print_line_t wakeup_print_line(struct trace_iterator *iter)
 	 * In graph mode call the graph tracer output function,
 	 * otherwise go with the TRACE_FN event handler
 	 */
-	if (is_graph())
+	if (is_graph(iter->tr))
 		return print_graph_function_flags(iter, GRAPH_TRACER_FLAGS);
 
 	return TRACE_TYPE_UNHANDLED;
@@ -287,7 +298,7 @@ static enum print_line_t wakeup_print_line(struct trace_iterator *iter)
 
 static void wakeup_print_header(struct seq_file *s)
 {
-	if (is_graph())
+	if (is_graph(wakeup_trace))
 		print_graph_headers_flags(s, GRAPH_TRACER_FLAGS);
 	else
 		trace_default_header(s);
@@ -298,7 +309,7 @@ __trace_function(struct trace_array *tr,
 		 unsigned long ip, unsigned long parent_ip,
 		 unsigned long flags, int pc)
 {
-	if (is_graph())
+	if (is_graph(tr))
 		trace_graph_function(tr, ip, parent_ip, flags, pc);
 	else
 		trace_function(tr, ip, parent_ip, flags, pc);
@@ -306,27 +317,20 @@ __trace_function(struct trace_array *tr,
 #else
 #define __trace_function trace_function
 
-static int
-wakeup_set_flag(struct trace_array *tr, u32 old_flags, u32 bit, int set)
-{
-	return -EINVAL;
-}
-
-static int wakeup_graph_entry(struct ftrace_graph_ent *trace)
-{
-	return -1;
-}
-
 static enum print_line_t wakeup_print_line(struct trace_iterator *iter)
 {
 	return TRACE_TYPE_UNHANDLED;
 }
 
-static void wakeup_graph_return(struct ftrace_graph_ret *trace) { }
 static void wakeup_trace_open(struct trace_iterator *iter) { }
 static void wakeup_trace_close(struct trace_iterator *iter) { }
 
 #ifdef CONFIG_FUNCTION_TRACER
+static int wakeup_graph_entry(struct ftrace_graph_ent *trace)
+{
+	return -1;
+}
+static void wakeup_graph_return(struct ftrace_graph_ret *trace) { }
 static void wakeup_print_header(struct seq_file *s)
 {
 	trace_default_header(s);
@@ -342,16 +346,16 @@ static void wakeup_print_header(struct seq_file *s)
 /*
  * Should this new latency be reported/recorded?
  */
-static int report_latency(struct trace_array *tr, cycle_t delta)
+static bool report_latency(struct trace_array *tr, cycle_t delta)
 {
 	if (tracing_thresh) {
 		if (delta < tracing_thresh)
-			return 0;
+			return false;
 	} else {
 		if (delta <= tr->max_latency)
-			return 0;
+			return false;
 	}
-	return 1;
+	return true;
 }
 
 static void
@@ -388,7 +392,7 @@ tracing_sched_switch_trace(struct trace_array *tr,
 	entry->next_cpu	= task_cpu(next);
 
 	if (!call_filter_check_discard(call, entry, buffer, event))
-		trace_buffer_unlock_commit(buffer, event, flags, pc);
+		trace_buffer_unlock_commit(tr, buffer, event, flags, pc);
 }
 
 static void
@@ -416,7 +420,7 @@ tracing_sched_wakeup_trace(struct trace_array *tr,
 	entry->next_cpu			= task_cpu(wakee);
 
 	if (!call_filter_check_discard(call, entry, buffer, event))
-		trace_buffer_unlock_commit(buffer, event, flags, pc);
+		trace_buffer_unlock_commit(tr, buffer, event, flags, pc);
 }
 
 static void notrace
@@ -635,7 +639,7 @@ static void start_wakeup_tracer(struct trace_array *tr)
 	 */
 	smp_wmb();
 
-	if (start_func_tracer(tr, is_graph()))
+	if (start_func_tracer(tr, is_graph(tr)))
 		printk(KERN_ERR "failed to start wakeup tracer\n");
 
 	return;
@@ -648,7 +652,7 @@ fail_deprobe:
 static void stop_wakeup_tracer(struct trace_array *tr)
 {
 	tracer_enabled = 0;
-	stop_func_tracer(tr, is_graph());
+	stop_func_tracer(tr, is_graph(tr));
 	unregister_trace_sched_switch(probe_wakeup_sched_switch, NULL);
 	unregister_trace_sched_wakeup_new(probe_wakeup, NULL);
 	unregister_trace_sched_wakeup(probe_wakeup, NULL);
@@ -659,7 +663,7 @@ static bool wakeup_busy;
 
 static int __wakeup_tracer_init(struct trace_array *tr)
 {
-	save_flags = trace_flags;
+	save_flags = tr->trace_flags;
 
 	/* non overwrite screws up the latency tracers */
 	set_tracer_flag(tr, TRACE_ITER_OVERWRITE, 1);
@@ -740,8 +744,6 @@ static struct tracer wakeup_tracer __read_mostly =
 	.print_max	= true,
 	.print_header	= wakeup_print_header,
 	.print_line	= wakeup_print_line,
-	.flags		= &tracer_flags,
-	.set_flag	= wakeup_set_flag,
 	.flag_changed	= wakeup_flag_changed,
 #ifdef CONFIG_FTRACE_SELFTEST
 	.selftest    = trace_selftest_startup_wakeup,
@@ -762,8 +764,6 @@ static struct tracer wakeup_rt_tracer __read_mostly =
 	.print_max	= true,
 	.print_header	= wakeup_print_header,
 	.print_line	= wakeup_print_line,
-	.flags		= &tracer_flags,
-	.set_flag	= wakeup_set_flag,
 	.flag_changed	= wakeup_flag_changed,
 #ifdef CONFIG_FTRACE_SELFTEST
 	.selftest    = trace_selftest_startup_wakeup,
@@ -784,8 +784,6 @@ static struct tracer wakeup_dl_tracer __read_mostly =
 	.print_max	= true,
 	.print_header	= wakeup_print_header,
 	.print_line	= wakeup_print_line,
-	.flags		= &tracer_flags,
-	.set_flag	= wakeup_set_flag,
 	.flag_changed	= wakeup_flag_changed,
 #ifdef CONFIG_FTRACE_SELFTEST
 	.selftest    = trace_selftest_startup_wakeup,