Commit 1a414428 authored by Steven Rostedt (Red Hat)'s avatar Steven Rostedt (Red Hat) Committed by Steven Rostedt

tracing/fgraph: Have wakeup and irqsoff tracers ignore graph functions too

Currently both the wakeup and irqsoff traces do not handle set_graph_notrace
well. The ftrace infrastructure will ignore the return paths of all
functions leaving them hanging without an end:

  # echo '*spin*' > set_graph_notrace
  # cat trace
  [...]
          _raw_spin_lock() {
            preempt_count_add() {
            do_raw_spin_lock() {
          update_rq_clock();

Where the '*spin*' functions should have looked like this:

          _raw_spin_lock() {
            preempt_count_add();
            do_raw_spin_lock();
          }
          update_rq_clock();

Instead, have the wakeup and irqsoff tracers ignore the functions that are
set by the set_graph_notrace like the function_graph tracer does. Move
the logic in the function_graph tracer into a header to allow wakeup and
irqsoff tracers to use it as well.

Cc: Namhyung Kim <namhyung.kim@lge.com>
Signed-off-by: default avatarSteven Rostedt <rostedt@goodmis.org>
parent 794de08a
......@@ -846,6 +846,17 @@ static inline int ftrace_graph_notrace_addr(unsigned long addr)
return 0;
}
#endif /* CONFIG_DYNAMIC_FTRACE */
extern unsigned int fgraph_max_depth;
static inline bool ftrace_graph_ignore_func(struct ftrace_graph_ent *trace)
{
/* trace it when it is-nested-in or is a function enabled. */
return !(trace->depth || ftrace_graph_addr(trace->func)) ||
(trace->depth < 0) ||
(fgraph_max_depth && trace->depth >= fgraph_max_depth);
}
#else /* CONFIG_FUNCTION_GRAPH_TRACER */
static inline enum print_line_t
print_graph_function_flags(struct trace_iterator *iter, u32 flags)
......
......@@ -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) */
......@@ -384,10 +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;
/*
......@@ -1500,7 +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;
......@@ -1514,7 +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);
}
......
......@@ -175,6 +175,18 @@ static int irqsoff_graph_entry(struct ftrace_graph_ent *trace)
int ret;
int pc;
if (ftrace_graph_ignore_func(trace))
return 0;
/*
* Do not trace a function if it's filtered by set_graph_notrace.
* Make the index of ret stack negative to indicate that it should
* ignore further functions. But it needs its own ret stack entry
* to recover the original index in order to continue tracing after
* returning from the function.
*/
if (ftrace_graph_notrace_addr(trace->func))
return 1;
if (!func_prolog_dec(tr, &data, &flags))
return 0;
......
......@@ -239,6 +239,18 @@ static int wakeup_graph_entry(struct ftrace_graph_ent *trace)
unsigned long flags;
int pc, ret = 0;
if (ftrace_graph_ignore_func(trace))
return 0;
/*
* Do not trace a function if it's filtered by set_graph_notrace.
* Make the index of ret stack negative to indicate that it should
* ignore further functions. But it needs its own ret stack entry
* to recover the original index in order to continue tracing after
* returning from the function.
*/
if (ftrace_graph_notrace_addr(trace->func))
return 1;
if (!func_prolog_preempt_disable(tr, &data, &pc))
return 0;
......
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