[PATCH v10 21/36] function_graph: Pass ftrace_regs to entryfunc

@@ -497,7 +497,7 @@ void ftrace_graph_func(unsigned long ip, unsigned long parent_ip,
 		return;
 
 	if (!function_graph_enter_ops(*parent, ip, frame_pointer,
-				      (void *)frame_pointer, gops))
+				      (void *)frame_pointer, fregs, gops))
 		*parent = (unsigned long)&return_to_handler;
 
 	ftrace_test_recursion_unlock(bit);

@@ -254,7 +254,7 @@ void ftrace_graph_func(unsigned long ip, unsigned long parent_ip,
 
 	old = *parent;
 
-	if (!function_graph_enter_ops(old, ip, 0, parent, gops))
+	if (!function_graph_enter_ops(old, ip, 0, parent, fregs, gops))
 		*parent = return_hooker;
 }
 #else

@@ -435,7 +435,7 @@ void ftrace_graph_func(unsigned long ip, unsigned long parent_ip,
 	if (bit < 0)
 		goto out;
 
-	if (!function_graph_enter_ops(parent_ip, ip, 0, (unsigned long *)sp, gops))
+	if (!function_graph_enter_ops(parent_ip, ip, 0, (unsigned long *)sp, fregs, gops))
 		parent_ip = ppc_function_entry(return_to_handler);
 
 	ftrace_test_recursion_unlock(bit);

@@ -800,7 +800,8 @@ int ftrace_disable_ftrace_graph_caller(void)
  * in current thread info. Return the address we want to divert to.
  */
 static unsigned long
-__prepare_ftrace_return(unsigned long parent, unsigned long ip, unsigned long sp)
+__prepare_ftrace_return(unsigned long parent, unsigned long ip, unsigned long sp,
+			struct ftrace_regs *fregs)
 {
 	unsigned long return_hooker;
 	int bit;

@@ -817,7 +818,7 @@ __prepare_ftrace_return(unsigned long parent, unsigned long ip, unsigned long sp
 
 	return_hooker = ppc_function_entry(return_to_handler);
 
-	if (!function_graph_enter(parent, ip, 0, (unsigned long *)sp))
+	if (!function_graph_enter_regs(parent, ip, 0, (unsigned long *)sp, fregs))
 		parent = return_hooker;
 
 	ftrace_test_recursion_unlock(bit);

@@ -829,13 +830,14 @@ __prepare_ftrace_return(unsigned long parent, unsigned long ip, unsigned long sp
 void ftrace_graph_func(unsigned long ip, unsigned long parent_ip,
 		       struct ftrace_ops *op, struct ftrace_regs *fregs)
 {
-	fregs->regs.link = __prepare_ftrace_return(parent_ip, ip, fregs->regs.gpr[1]);
+	fregs->regs.link = __prepare_ftrace_return(parent_ip, ip,
+						   fregs->regs.gpr[1], fregs);
 }
 #else
 unsigned long prepare_ftrace_return(unsigned long parent, unsigned long ip,
 				    unsigned long sp)
 {
-	return __prepare_ftrace_return(parent, ip, sp);
+	return __prepare_ftrace_return(parent, ip, sp, NULL);
 }
 #endif
 #endif /* CONFIG_FUNCTION_GRAPH_TRACER */

@@ -197,7 +197,7 @@ void ftrace_graph_func(unsigned long ip, unsigned long parent_ip,
 	 */
 	old = *parent;
 
-	if (!function_graph_enter_ops(old, ip, frame_pointer(regs), parent, gops))
+	if (!function_graph_enter_ops(old, ip, frame_pointer(regs), parent, fregs, gops))
 		*parent = return_hooker;
 }
 #else /* CONFIG_DYNAMIC_FTRACE_WITH_REGS */

@@ -615,16 +615,8 @@ int ftrace_disable_ftrace_graph_caller(void)
 }
 #endif /* CONFIG_DYNAMIC_FTRACE && !CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS */
 
-/*
- * Hook the return address and push it in the stack of return addrs
- * in current thread info.
- */
-void prepare_ftrace_return(unsigned long ip, unsigned long *parent,
-			   unsigned long frame_pointer)
+static inline bool skip_ftrace_return(void)
 {
-	unsigned long return_hooker = (unsigned long)&return_to_handler;
-	int bit;
-
 	/*
 	 * When resuming from suspend-to-ram, this function can be indirectly
 	 * called from early CPU startup code while the CPU is in real mode,

@@ -634,13 +626,28 @@ void prepare_ftrace_return(unsigned long ip, unsigned long *parent,
 	 * This check isn't as accurate as virt_addr_valid(), but it should be
 	 * good enough for this purpose, and it's fast.
 	 */
-	if (unlikely((long)__builtin_frame_address(0) >= 0))
-		return;
+	if ((long)__builtin_frame_address(0) >= 0)
+		return true;
 
-	if (unlikely(ftrace_graph_is_dead()))
-		return;
+	if (ftrace_graph_is_dead())
+		return true;
+
+	if (atomic_read(&current->tracing_graph_pause))
+		return true;
+	return false;
+}
 
-	if (unlikely(atomic_read(&current->tracing_graph_pause)))
+/*
+ * Hook the return address and push it in the stack of return addrs
+ * in current thread info.
+ */
+void prepare_ftrace_return(unsigned long ip, unsigned long *parent,
+			   unsigned long frame_pointer)
+{
+	unsigned long return_hooker = (unsigned long)&return_to_handler;
+	int bit;
+
+	if (unlikely(skip_ftrace_return()))
 		return;
 
 	bit = ftrace_test_recursion_trylock(ip, *parent);

@@ -662,17 +669,14 @@ void ftrace_graph_func(unsigned long ip, unsigned long parent_ip,
 	struct fgraph_ops *gops = container_of(op, struct fgraph_ops, ops);
 	int bit;
 
-	if (unlikely(ftrace_graph_is_dead()))
-		return;
-
-	if (unlikely(atomic_read(&current->tracing_graph_pause)))
+	if (unlikely(skip_ftrace_return()))
 		return;
 
 	bit = ftrace_test_recursion_trylock(ip, *parent);
 	if (bit < 0)
 		return;
 
-	if (!function_graph_enter_ops(*parent, ip, 0, parent, gops))
+	if (!function_graph_enter_ops(*parent, ip, 0, parent, fregs, gops))
 		*parent = (unsigned long)&return_to_handler;
 
 	ftrace_test_recursion_unlock(bit);

@@ -1061,9 +1061,12 @@ struct fgraph_ops;
 typedef void (*trace_func_graph_ret_t)(struct ftrace_graph_ret *,
 				       struct fgraph_ops *); /* return */
 typedef int (*trace_func_graph_ent_t)(struct ftrace_graph_ent *,
-				      struct fgraph_ops *); /* entry */
+				      struct fgraph_ops *,
+				      struct ftrace_regs *); /* entry */
 
-extern int ftrace_graph_entry_stub(struct ftrace_graph_ent *trace, struct fgraph_ops *gops);
+extern int ftrace_graph_entry_stub(struct ftrace_graph_ent *trace,
+				   struct fgraph_ops *gops,
+				   struct ftrace_regs *fregs);
 
 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
 

@@ -1106,13 +1109,20 @@ struct ftrace_ret_stack {
 extern void return_to_handler(void);
 
 extern int
-function_graph_enter(unsigned long ret, unsigned long func,
-		     unsigned long frame_pointer, unsigned long *retp);
+function_graph_enter_regs(unsigned long ret, unsigned long func,
+			  unsigned long frame_pointer, unsigned long *retp,
+			  struct ftrace_regs *fregs);
+
+static inline int function_graph_enter(unsigned long ret, unsigned long func,
+				       unsigned long fp, unsigned long *retp)
+{
+	return function_graph_enter_regs(ret, func, fp, retp, NULL);
+}
 
 extern int
 function_graph_enter_ops(unsigned long ret, unsigned long func,
 			 unsigned long frame_pointer, unsigned long *retp,
-			 struct fgraph_ops *gops);
+			 struct ftrace_regs *fregs, struct fgraph_ops *gops);
 
 struct ftrace_ret_stack *
 ftrace_graph_get_ret_stack(struct task_struct *task, int skip);

@@ -257,7 +257,8 @@ static inline unsigned long make_fgraph_data(int idx, int size, int offset)
 }
 
 /* ftrace_graph_entry set to this to tell some archs to run function graph */
-static int entry_run(struct ftrace_graph_ent *trace, struct fgraph_ops *ops)
+static int entry_run(struct ftrace_graph_ent *trace, struct fgraph_ops *ops,
+		     struct ftrace_regs *fregs)
 {
 	return 0;
 }

@@ -448,7 +449,7 @@ int __weak ftrace_disable_ftrace_graph_caller(void)
 #endif
 
 int ftrace_graph_entry_stub(struct ftrace_graph_ent *trace,
-			    struct fgraph_ops *gops)
+			    struct fgraph_ops *gops, struct ftrace_regs *fregs)
 {
 	return 0;
 }

@@ -582,8 +583,9 @@ ftrace_push_return_trace(unsigned long ret, unsigned long func,
 #endif
 
 /* If the caller does not use ftrace, call this function. */
-int function_graph_enter(unsigned long ret, unsigned long func,
-			 unsigned long frame_pointer, unsigned long *retp)
+int function_graph_enter_regs(unsigned long ret, unsigned long func,
+			      unsigned long frame_pointer, unsigned long *retp,
+			      struct ftrace_regs *fregs)
 {
 	struct ftrace_graph_ent trace;
 	unsigned long bitmap = 0;

@@ -618,7 +620,7 @@ int function_graph_enter(unsigned long ret, unsigned long func,
 
 		save_curr_ret_stack = current->curr_ret_stack;
 		if (ftrace_ops_test(&gops->ops, func, NULL) &&
-		    gops->entryfunc(&trace, gops))
+		    gops->entryfunc(&trace, gops, fregs))
 			bitmap |= BIT(i);
 		else
 			/* Clear out any saved storage */

@@ -645,6 +647,7 @@ int function_graph_enter(unsigned long ret, unsigned long func,
 /* This is called from ftrace_graph_func() via ftrace */
 int function_graph_enter_ops(unsigned long ret, unsigned long func,
 			     unsigned long frame_pointer, unsigned long *retp,
+			     struct ftrace_regs *fregs,
 			     struct fgraph_ops *gops)
 {
 	struct ftrace_graph_ent trace;

@@ -669,7 +672,7 @@ int function_graph_enter_ops(unsigned long ret, unsigned long func,
 	trace.func = func;
 	trace.depth = current->curr_ret_depth;
 	save_curr_ret_stack = current->curr_ret_stack;
-	if (gops->entryfunc(&trace, gops)) {
+	if (gops->entryfunc(&trace, gops, fregs)) {
 		if (type == FGRAPH_TYPE_RESERVED)
 			set_fgraph_index_bitmap(current, offset, BIT(gops->idx));
 		else

@@ -950,7 +953,8 @@ void fgraph_init_ops(struct ftrace_ops *dst_ops,
 		     struct ftrace_ops *src_ops)
 {
 	dst_ops->func = ftrace_graph_func;
-	dst_ops->flags = FTRACE_OPS_FL_PID | FTRACE_OPS_GRAPH_STUB;
+	dst_ops->flags = FTRACE_OPS_FL_PID | FTRACE_OPS_GRAPH_STUB |
+			 FTRACE_OPS_FL_SAVE_ARGS;
 
 #ifdef FTRACE_GRAPH_TRAMP_ADDR
 	dst_ops->trampoline = FTRACE_GRAPH_TRAMP_ADDR;

@@ -1195,7 +1199,8 @@ int register_ftrace_graph(struct fgraph_ops *gops)
 	mutex_lock(&ftrace_lock);
 
 	if (!gops->ops.func) {
-		gops->ops.flags |= FTRACE_OPS_GRAPH_STUB;
+		gops->ops.flags |= FTRACE_OPS_GRAPH_STUB |
+				   FTRACE_OPS_FL_SAVE_ARGS;
 		gops->ops.func = ftrace_graph_func;
 #ifdef FTRACE_GRAPH_TRAMP_ADDR
 		gops->ops.trampoline = FTRACE_GRAPH_TRAMP_ADDR;

@@ -816,7 +816,8 @@ void ftrace_graph_graph_time_control(bool enable)
 }
 
 static int profile_graph_entry(struct ftrace_graph_ent *trace,
-			       struct fgraph_ops *gops)
+			       struct fgraph_ops *gops,
+			       struct ftrace_regs *fregs)
 {
 	struct ftrace_ret_stack *ret_stack;
 

@@ -682,7 +682,8 @@ void trace_default_header(struct seq_file *m);
 void print_trace_header(struct seq_file *m, struct trace_iterator *iter);
 
 void trace_graph_return(struct ftrace_graph_ret *trace, struct fgraph_ops *gops);
-int trace_graph_entry(struct ftrace_graph_ent *trace, struct fgraph_ops *gops);
+int trace_graph_entry(struct ftrace_graph_ent *trace, struct fgraph_ops *gops,
+		      struct ftrace_regs *fregs);
 
 void tracing_start_cmdline_record(void);
 void tracing_stop_cmdline_record(void);

@@ -128,7 +128,8 @@ static inline int ftrace_graph_ignore_irqs(void)
 }
 
 int trace_graph_entry(struct ftrace_graph_ent *trace,
-		      struct fgraph_ops *gops)
+		      struct fgraph_ops *gops,
+		      struct ftrace_regs *fregs)
 {
 	unsigned long *task_var = fgraph_get_task_var(gops);
 	struct trace_array *tr = gops->private;

@@ -176,7 +176,8 @@ static int irqsoff_display_graph(struct trace_array *tr, int set)
 }
 
 static int irqsoff_graph_entry(struct ftrace_graph_ent *trace,
-			       struct fgraph_ops *gops)
+			       struct fgraph_ops *gops,
+			       struct ftrace_regs *fregs)
 {
 	struct trace_array *tr = irqsoff_trace;
 	struct trace_array_cpu *data;

@@ -113,7 +113,8 @@ static int wakeup_display_graph(struct trace_array *tr, int set)
 }
 
 static int wakeup_graph_entry(struct ftrace_graph_ent *trace,
-			      struct fgraph_ops *gops)
+			      struct fgraph_ops *gops,
+			      struct ftrace_regs *fregs)
 {
 	struct trace_array *tr = wakeup_trace;
 	struct trace_array_cpu *data;

@@ -773,7 +773,8 @@ struct fgraph_fixture {
 };
 
 static __init int store_entry(struct ftrace_graph_ent *trace,
-			      struct fgraph_ops *gops)
+			      struct fgraph_ops *gops,
+			      struct ftrace_regs *fregs)
 {
 	struct fgraph_fixture *fixture = container_of(gops, struct fgraph_fixture, gops);
 	const char *type = fixture->store_type_name;

@@ -1011,7 +1012,8 @@ static unsigned int graph_hang_thresh;
 
 /* Wrap the real function entry probe to avoid possible hanging */
 static int trace_graph_entry_watchdog(struct ftrace_graph_ent *trace,
-				      struct fgraph_ops *gops)
+				      struct fgraph_ops *gops,
+				      struct ftrace_regs *fregs)
 {
 	/* This is harmlessly racy, we want to approximately detect a hang */
 	if (unlikely(++graph_hang_thresh > GRAPH_MAX_FUNC_TEST)) {

@@ -1025,7 +1027,7 @@ static int trace_graph_entry_watchdog(struct ftrace_graph_ent *trace,
 		return 0;
 	}
 
-	return trace_graph_entry(trace, gops);
+	return trace_graph_entry(trace, gops, fregs);
 }
 
 static struct fgraph_ops fgraph_ops __initdata  = {