function_graph: Remove the use of FTRACE_NOTRACE_DEPTH

The curr_ret_stack is no longer set to a negative value when a function is
not to be traced by the function graph tracer. Remove the usage of
FTRACE_NOTRACE_DEPTH, as it is no longer needed.

Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
This commit is contained in:
Steven Rostedt (VMware) 2018-11-18 18:44:04 -05:00
parent 421d1069cd
commit 761efe8a94
3 changed files with 0 additions and 31 deletions

View File

@ -790,7 +790,6 @@ unsigned long ftrace_graph_ret_addr(struct task_struct *task, int *idx,
*/
#define __notrace_funcgraph notrace
#define FTRACE_NOTRACE_DEPTH 65536
#define FTRACE_RETFUNC_DEPTH 50
#define FTRACE_RETSTACK_ALLOC_SIZE 32
extern int register_ftrace_graph(trace_func_graph_ret_t retfunc,

View File

@ -112,16 +112,6 @@ ftrace_pop_return_trace(struct ftrace_graph_ret *trace, unsigned long *ret,
index = current->curr_ret_stack;
/*
* A negative index here means that it's just returned from a
* notrace'd function. Recover index to get an original
* return address. See ftrace_push_return_trace().
*
* TODO: Need to check whether the stack gets corrupted.
*/
if (index < 0)
index += FTRACE_NOTRACE_DEPTH;
if (unlikely(index < 0 || index >= FTRACE_RETFUNC_DEPTH)) {
ftrace_graph_stop();
WARN_ON(1);
@ -190,15 +180,6 @@ unsigned long ftrace_return_to_handler(unsigned long frame_pointer)
*/
barrier();
current->curr_ret_stack--;
/*
* The curr_ret_stack can be less than -1 only if it was
* filtered out and it's about to return from the function.
* Recover the index and continue to trace normal functions.
*/
if (current->curr_ret_stack < -1) {
current->curr_ret_stack += FTRACE_NOTRACE_DEPTH;
return ret;
}
if (unlikely(!ret)) {
ftrace_graph_stop();

View File

@ -115,9 +115,6 @@ unsigned long ftrace_graph_ret_addr(struct task_struct *task, int *idx,
if (ret != (unsigned long)return_to_handler)
return ret;
if (index < -1)
index += FTRACE_NOTRACE_DEPTH;
if (index < 0)
return ret;
@ -675,10 +672,6 @@ 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
@ -721,10 +714,6 @@ 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;