Re: [PATCH] ftrace: Remove use of control list and ops

From: Jiri Olsa
Date: Wed Dec 02 2015 - 03:58:33 EST


On Tue, Dec 01, 2015 at 11:56:55AM -0500, Steven Rostedt wrote:

SNIP

> -static void ftrace_ops_recurs_func(unsigned long ip, unsigned long parent_ip,
> +static void ftrace_ops_assist_func(unsigned long ip, unsigned long parent_ip,
> struct ftrace_ops *op, struct pt_regs *regs)
> {
> int bit;
>
> + if ((op->flags & FTRACE_OPS_FL_RCU) && !rcu_is_watching())
> + return;
> +
> bit = trace_test_and_set_recursion(TRACE_LIST_START, TRACE_LIST_MAX);
> if (bit < 0)
> return;
>
> - op->func(ip, parent_ip, op, regs);
> + preempt_disable_notrace();
>
> + if (!(op->flags & FTRACE_OPS_FL_PER_CPU) ||
> + ftrace_function_local_disabled(op)) {

should be !ftrace_function_local_disabled(op) in here,
I passed my test with attached patch

thanks,
jirka

> + op->func(ip, parent_ip, op, regs);
> + }
> +
> + preempt_enable_notrace();
> trace_clear_recursion(bit);
> }

SNIP

---
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 710430fcfd9c..ad0e0e7eaea2 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -115,7 +115,7 @@ static struct ftrace_ops *ftrace_ops_list __read_mostly = &ftrace_list_end;
ftrace_func_t ftrace_trace_function __read_mostly = ftrace_stub;
static struct ftrace_ops global_ops;

-static void ftrace_ops_recurs_func(unsigned long ip, unsigned long parent_ip,
+static void ftrace_ops_assist_func(unsigned long ip, unsigned long parent_ip,
struct ftrace_ops *op, struct pt_regs *regs);

#if ARCH_SUPPORTS_FTRACE_OPS
@@ -5180,7 +5180,7 @@ static void ftrace_ops_assist_func(unsigned long ip, unsigned long parent_ip,
preempt_disable_notrace();

if (!(op->flags & FTRACE_OPS_FL_PER_CPU) ||
- ftrace_function_local_disabled(op)) {
+ !ftrace_function_local_disabled(op)) {
op->func(ip, parent_ip, op, regs);
}

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/