tracing/function-graph-tracer: handle ftrace_printk entries
Handle the TRACE_PRINT entries from the function grapg tracer
and output them as a C comment just below the function that called
it, as if it was a comment inside this function.
Example with an ftrace_printk inside might_sleep() function:
void __might_sleep(char *file, int line)
{
static unsigned long prev_jiffy; /* ratelimiting */
ftrace_printk("Hi I'm a comment in might_sleep() :-)");
A chunk of a resulting trace:
0) | _reiserfs_free_block() {
0) | reiserfs_read_bitmap_block() {
0) | __bread() {
0) | __getblk() {
0) | __find_get_block() {
0) 0.698 us | mark_page_accessed();
0) 2.267 us | }
0) | __might_sleep() {
0) | /* Hi I'm a comment in might_sleep() :-) */
0) 1.321 us | }
0) 5.872 us | }
0) 7.313 us | }
0) 8.718 us | }
And this patch brings two minor fixes:
- The newline after a switch-out task has disappeared
- The "|" sign just before the cpu number on task-switch has been deleted.
0) 0.616 us | pick_next_task_rt();
0) 1.457 us | _spin_trylock();
0) 0.653 us | _spin_unlock();
0) 0.728 us | _spin_trylock();
0) 0.631 us | _spin_unlock();
0) 0.729 us | native_load_sp0();
0) 0.593 us | native_load_tls();
------------------------------------------
0) cat-2834 => migrati-3
------------------------------------------
0) | finish_task_switch() {
0) 0.841 us | _spin_unlock_irq();
0) 0.616 us | post_schedule_rt();
0) 3.882 us | }
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
index c66578f..32b7fb9 100644
--- a/kernel/trace/trace_functions_graph.c
+++ b/kernel/trace/trace_functions_graph.c
@@ -173,7 +173,7 @@
*/
ret = trace_seq_printf(s,
- "\n ------------------------------------------\n |");
+ " ------------------------------------------\n");
if (!ret)
TRACE_TYPE_PARTIAL_LINE;
@@ -477,6 +477,71 @@
return TRACE_TYPE_HANDLED;
}
+static enum print_line_t
+print_graph_comment(struct print_entry *trace, struct trace_seq *s,
+ struct trace_entry *ent, struct trace_iterator *iter)
+{
+ int i;
+ int ret;
+
+ /* Pid */
+ if (verif_pid(s, ent->pid, iter->cpu) == TRACE_TYPE_PARTIAL_LINE)
+ return TRACE_TYPE_PARTIAL_LINE;
+
+ /* Cpu */
+ if (tracer_flags.val & TRACE_GRAPH_PRINT_CPU) {
+ ret = print_graph_cpu(s, iter->cpu);
+ if (ret == TRACE_TYPE_PARTIAL_LINE)
+ return TRACE_TYPE_PARTIAL_LINE;
+ }
+
+ /* Proc */
+ if (tracer_flags.val & TRACE_GRAPH_PRINT_PROC) {
+ ret = print_graph_proc(s, ent->pid);
+ if (ret == TRACE_TYPE_PARTIAL_LINE)
+ return TRACE_TYPE_PARTIAL_LINE;
+
+ ret = trace_seq_printf(s, " | ");
+ if (!ret)
+ return TRACE_TYPE_PARTIAL_LINE;
+ }
+
+ /* No overhead */
+ if (tracer_flags.val & TRACE_GRAPH_PRINT_OVERHEAD) {
+ ret = trace_seq_printf(s, " ");
+ if (!ret)
+ return TRACE_TYPE_PARTIAL_LINE;
+ }
+
+ /* No time */
+ ret = trace_seq_printf(s, " | ");
+ if (!ret)
+ return TRACE_TYPE_PARTIAL_LINE;
+
+ /* Indentation */
+ if (trace->depth > 0)
+ for (i = 0; i < (trace->depth + 1) * TRACE_GRAPH_INDENT; i++) {
+ ret = trace_seq_printf(s, " ");
+ if (!ret)
+ return TRACE_TYPE_PARTIAL_LINE;
+ }
+
+ /* The comment */
+ ret = trace_seq_printf(s, "/* %s", trace->buf);
+ if (!ret)
+ return TRACE_TYPE_PARTIAL_LINE;
+
+ if (ent->flags & TRACE_FLAG_CONT)
+ trace_seq_print_cont(s, iter);
+
+ ret = trace_seq_printf(s, " */\n");
+ if (!ret)
+ return TRACE_TYPE_PARTIAL_LINE;
+
+ return TRACE_TYPE_HANDLED;
+}
+
+
enum print_line_t
print_graph_function(struct trace_iterator *iter)
{
@@ -495,6 +560,11 @@
trace_assign_type(field, entry);
return print_graph_return(&field->ret, s, entry, iter->cpu);
}
+ case TRACE_PRINT: {
+ struct print_entry *field;
+ trace_assign_type(field, entry);
+ return print_graph_comment(field, s, entry, iter);
+ }
default:
return TRACE_TYPE_UNHANDLED;
}
