tracing/function-return-tracer: change the name into function-graph-tracer
Impact: cleanup
This patch changes the name of the "return function tracer" into
function-graph-tracer which is a more suitable name for a tracing
which makes one able to retrieve the ordered call stack during
the code flow.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/kernel/trace/trace_functions_graph.c b/kernel/trace/trace_functions_graph.c
new file mode 100644
index 0000000..f5bad46
--- /dev/null
+++ b/kernel/trace/trace_functions_graph.c
@@ -0,0 +1,98 @@
+/*
+ *
+ * Function graph tracer.
+ * Copyright (c) 2008 Frederic Weisbecker <fweisbec@gmail.com>
+ * Mostly borrowed from function tracer which
+ * is Copyright (c) Steven Rostedt <srostedt@redhat.com>
+ *
+ */
+#include <linux/debugfs.h>
+#include <linux/uaccess.h>
+#include <linux/ftrace.h>
+#include <linux/fs.h>
+
+#include "trace.h"
+
+
+#define TRACE_GRAPH_PRINT_OVERRUN 0x1
+static struct tracer_opt trace_opts[] = {
+ /* Display overruns or not */
+ { TRACER_OPT(overrun, TRACE_GRAPH_PRINT_OVERRUN) },
+ { } /* Empty entry */
+};
+
+static struct tracer_flags tracer_flags = {
+ .val = 0, /* Don't display overruns by default */
+ .opts = trace_opts
+};
+
+
+static int graph_trace_init(struct trace_array *tr)
+{
+ int cpu;
+ for_each_online_cpu(cpu)
+ tracing_reset(tr, cpu);
+
+ return register_ftrace_graph(&trace_function_graph);
+}
+
+static void graph_trace_reset(struct trace_array *tr)
+{
+ unregister_ftrace_graph();
+}
+
+
+enum print_line_t
+print_graph_function(struct trace_iterator *iter)
+{
+ struct trace_seq *s = &iter->seq;
+ struct trace_entry *entry = iter->ent;
+ struct ftrace_graph_entry *field;
+ int ret;
+
+ if (entry->type == TRACE_FN_RET) {
+ trace_assign_type(field, entry);
+ ret = trace_seq_printf(s, "%pF -> ", (void *)field->parent_ip);
+ if (!ret)
+ return TRACE_TYPE_PARTIAL_LINE;
+
+ ret = seq_print_ip_sym(s, field->ip,
+ trace_flags & TRACE_ITER_SYM_MASK);
+ if (!ret)
+ return TRACE_TYPE_PARTIAL_LINE;
+
+ ret = trace_seq_printf(s, " (%llu ns)",
+ field->rettime - field->calltime);
+ if (!ret)
+ return TRACE_TYPE_PARTIAL_LINE;
+
+ if (tracer_flags.val & TRACE_GRAPH_PRINT_OVERRUN) {
+ ret = trace_seq_printf(s, " (Overruns: %lu)",
+ field->overrun);
+ if (!ret)
+ return TRACE_TYPE_PARTIAL_LINE;
+ }
+
+ ret = trace_seq_printf(s, "\n");
+ if (!ret)
+ return TRACE_TYPE_PARTIAL_LINE;
+
+ return TRACE_TYPE_HANDLED;
+ }
+ return TRACE_TYPE_UNHANDLED;
+}
+
+static struct tracer graph_trace __read_mostly = {
+ .name = "function-graph",
+ .init = graph_trace_init,
+ .reset = graph_trace_reset,
+ .print_line = print_graph_function,
+ .flags = &tracer_flags,
+};
+
+static __init int init_graph_trace(void)
+{
+ return register_tracer(&graph_trace);
+}
+
+device_initcall(init_graph_trace);