1 files changed, 93 insertions, 15 deletions

diff --git a/kernel/trace/trace_functions_graph.c b/kernel/trace/trace_functions_graph.c
index 7363ccf79512..d56123cdcc89 100644
--- a/kernel/trace/trace_functions_graph.c
+++ b/kernel/trace/trace_functions_graph.c
@@ -65,7 +65,7 @@ struct fgraph_data {
 
 #define TRACE_GRAPH_INDENT	2
 
-static unsigned int max_depth;
+unsigned int fgraph_max_depth;
 
 static struct tracer_opt trace_opts[] = {
 	/* Display overruns? (for self-debug purpose) */
@@ -119,7 +119,7 @@ print_graph_duration(struct trace_array *tr, unsigned long long duration,
 /* Add a function return address to the trace stack on thread info.*/
 int
 ftrace_push_return_trace(unsigned long ret, unsigned long func, int *depth,
-			 unsigned long frame_pointer)
+			 unsigned long frame_pointer, unsigned long *retp)
 {
 	unsigned long long calltime;
 	int index;
@@ -170,8 +170,12 @@ ftrace_push_return_trace(unsigned long ret, unsigned long func, int *depth,
 	current->ret_stack[index].ret = ret;
 	current->ret_stack[index].func = func;
 	current->ret_stack[index].calltime = calltime;
-	current->ret_stack[index].subtime = 0;
+#ifdef HAVE_FUNCTION_GRAPH_FP_TEST
 	current->ret_stack[index].fp = frame_pointer;
+#endif
+#ifdef HAVE_FUNCTION_GRAPH_RET_ADDR_PTR
+	current->ret_stack[index].retp = retp;
+#endif
 	*depth = current->curr_ret_stack;
 
 	return 0;
@@ -204,7 +208,7 @@ ftrace_pop_return_trace(struct ftrace_graph_ret *trace, unsigned long *ret,
 		return;
 	}
 
-#if defined(CONFIG_HAVE_FUNCTION_GRAPH_FP_TEST) && !defined(CC_USING_FENTRY)
+#ifdef HAVE_FUNCTION_GRAPH_FP_TEST
 	/*
 	 * The arch may choose to record the frame pointer used
 	 * and check it here to make sure that it is what we expect it
@@ -279,6 +283,64 @@ unsigned long ftrace_return_to_handler(unsigned long frame_pointer)
 	return ret;
 }
 
+/**
+ * ftrace_graph_ret_addr - convert a potentially modified stack return address
+ *			   to its original value
+ *
+ * This function can be called by stack unwinding code to convert a found stack
+ * return address ('ret') to its original value, in case the function graph
+ * tracer has modified it to be 'return_to_handler'.  If the address hasn't
+ * been modified, the unchanged value of 'ret' is returned.
+ *
+ * 'idx' is a state variable which should be initialized by the caller to zero
+ * before the first call.
+ *
+ * 'retp' is a pointer to the return address on the stack.  It's ignored if
+ * the arch doesn't have HAVE_FUNCTION_GRAPH_RET_ADDR_PTR defined.
+ */
+#ifdef HAVE_FUNCTION_GRAPH_RET_ADDR_PTR
+unsigned long ftrace_graph_ret_addr(struct task_struct *task, int *idx,
+				    unsigned long ret, unsigned long *retp)
+{
+	int index = task->curr_ret_stack;
+	int i;
+
+	if (ret != (unsigned long)return_to_handler)
+		return ret;
+
+	if (index < -1)
+		index += FTRACE_NOTRACE_DEPTH;
+
+	if (index < 0)
+		return ret;
+
+	for (i = 0; i <= index; i++)
+		if (task->ret_stack[i].retp == retp)
+			return task->ret_stack[i].ret;
+
+	return ret;
+}
+#else /* !HAVE_FUNCTION_GRAPH_RET_ADDR_PTR */
+unsigned long ftrace_graph_ret_addr(struct task_struct *task, int *idx,
+				    unsigned long ret, unsigned long *retp)
+{
+	int task_idx;
+
+	if (ret != (unsigned long)return_to_handler)
+		return ret;
+
+	task_idx = task->curr_ret_stack;
+
+	if (!task->ret_stack || task_idx < *idx)
+		return ret;
+
+	task_idx -= *idx;
+	(*idx)++;
+
+	return task->ret_stack[task_idx].ret;
+}
+#endif /* HAVE_FUNCTION_GRAPH_RET_ADDR_PTR */
+
 int __trace_graph_entry(struct trace_array *tr,
 				struct ftrace_graph_ent *trace,
 				unsigned long flags,
@@ -296,7 +358,7 @@ int __trace_graph_entry(struct trace_array *tr,
 	entry	= ring_buffer_event_data(event);
 	entry->graph_ent			= *trace;
 	if (!call_filter_check_discard(call, entry, buffer, event))
-		__buffer_unlock_commit(buffer, event);
+		trace_buffer_unlock_commit_nostack(buffer, event);
 
 	return 1;
 }
@@ -322,10 +384,10 @@ int trace_graph_entry(struct ftrace_graph_ent *trace)
 	if (!ftrace_trace_task(tr))
 		return 0;
 
-	/* trace it when it is-nested-in or is a function enabled. */
-	if ((!(trace->depth || ftrace_graph_addr(trace->func)) ||
-	     ftrace_graph_ignore_irqs()) || (trace->depth < 0) ||
-	    (max_depth && trace->depth >= max_depth))
+	if (ftrace_graph_ignore_func(trace))
+		return 0;
+
+	if (ftrace_graph_ignore_irqs())
 		return 0;
 
 	/*
@@ -407,7 +469,7 @@ void __trace_graph_return(struct trace_array *tr,
 	entry	= ring_buffer_event_data(event);
 	entry->ret				= *trace;
 	if (!call_filter_check_discard(call, entry, buffer, event))
-		__buffer_unlock_commit(buffer, event);
+		trace_buffer_unlock_commit_nostack(buffer, event);
 }
 
 void trace_graph_return(struct ftrace_graph_ret *trace)
@@ -780,6 +842,10 @@ print_graph_entry_leaf(struct trace_iterator *iter,
 
 		cpu_data = per_cpu_ptr(data->cpu_data, cpu);
 
+		/* If a graph tracer ignored set_graph_notrace */
+		if (call->depth < -1)
+			call->depth += FTRACE_NOTRACE_DEPTH;
+
 		/*
 		 * Comments display at + 1 to depth. Since
 		 * this is a leaf function, keep the comments
@@ -788,7 +854,8 @@ print_graph_entry_leaf(struct trace_iterator *iter,
 		cpu_data->depth = call->depth - 1;
 
 		/* No need to keep this function around for this depth */
-		if (call->depth < FTRACE_RETFUNC_DEPTH)
+		if (call->depth < FTRACE_RETFUNC_DEPTH &&
+		    !WARN_ON_ONCE(call->depth < 0))
 			cpu_data->enter_funcs[call->depth] = 0;
 	}
 
@@ -818,11 +885,16 @@ print_graph_entry_nested(struct trace_iterator *iter,
 		struct fgraph_cpu_data *cpu_data;
 		int cpu = iter->cpu;
 
+		/* If a graph tracer ignored set_graph_notrace */
+		if (call->depth < -1)
+			call->depth += FTRACE_NOTRACE_DEPTH;
+
 		cpu_data = per_cpu_ptr(data->cpu_data, cpu);
 		cpu_data->depth = call->depth;
 
 		/* Save this function pointer to see if the exit matches */
-		if (call->depth < FTRACE_RETFUNC_DEPTH)
+		if (call->depth < FTRACE_RETFUNC_DEPTH &&
+		    !WARN_ON_ONCE(call->depth < 0))
 			cpu_data->enter_funcs[call->depth] = call->func;
 	}
 
@@ -1052,7 +1124,8 @@ print_graph_return(struct ftrace_graph_ret *trace, struct trace_seq *s,
 		 */
 		cpu_data->depth = trace->depth - 1;
 
-		if (trace->depth < FTRACE_RETFUNC_DEPTH) {
+		if (trace->depth < FTRACE_RETFUNC_DEPTH &&
+		    !WARN_ON_ONCE(trace->depth < 0)) {
 			if (cpu_data->enter_funcs[trace->depth] != trace->func)
 				func_match = 0;
 			cpu_data->enter_funcs[trace->depth] = 0;
@@ -1120,6 +1193,11 @@ print_graph_comment(struct trace_seq *s, struct trace_entry *ent,
 	trace_seq_puts(s, "/* ");
 
 	switch (iter->ent->type) {
+	case TRACE_BPUTS:
+		ret = trace_print_bputs_msg_only(iter);
+		if (ret != TRACE_TYPE_HANDLED)
+			return ret;
+		break;
 	case TRACE_BPRINT:
 		ret = trace_print_bprintk_msg_only(iter);
 		if (ret != TRACE_TYPE_HANDLED)
@@ -1422,7 +1500,7 @@ graph_depth_write(struct file *filp, const char __user *ubuf, size_t cnt,
 	if (ret)
 		return ret;
 
-	max_depth = val;
+	fgraph_max_depth = val;
 
 	*ppos += cnt;
 
@@ -1436,7 +1514,7 @@ graph_depth_read(struct file *filp, char __user *ubuf, size_t cnt,
 	char buf[15]; /* More than enough to hold UINT_MAX + "\n"*/
 	int n;
 
-	n = sprintf(buf, "%d\n", max_depth);
+	n = sprintf(buf, "%d\n", fgraph_max_depth);
 
 	return simple_read_from_buffer(ubuf, cnt, ppos, buf, n);
 }