Re: [PATCH v7 13/36] function_graph: Have the instances use their own ftrace_ops for filtering

[Masami Hiramatsu (Google) <mhiramat@kernel.org>]

On Wed,  7 Feb 2024 00:09:54 +0900
"Masami Hiramatsu (Google)" <mhiramat@kernel.org> wrote:

> diff --git a/arch/loongarch/kernel/ftrace_dyn.c b/arch/loongarch/kernel/ftrace_dyn.c
> index 73858c9029cc..81d18b911cc1 100644
> --- a/arch/loongarch/kernel/ftrace_dyn.c
> +++ b/arch/loongarch/kernel/ftrace_dyn.c
> @@ -241,10 +241,17 @@ void prepare_ftrace_return(unsigned long self_addr, unsigned long *parent)
>  void ftrace_graph_func(unsigned long ip, unsigned long parent_ip,
>  		       struct ftrace_ops *op, struct ftrace_regs *fregs)
>  {
> +	struct fgraph_ops *gops = container_of(op, struct fgraph_ops, ops);
>  	struct pt_regs *regs = &fregs->regs;
>  	unsigned long *parent = (unsigned long *)&regs->regs[1];
>  
> -	prepare_ftrace_return(ip, (unsigned long *)parent);
> +	if (unlikely(atomic_read(&current->tracing_graph_pause)))
> +		return;
> +
> +	old = *parent;

Oops, this caused an error. 

> +
> +	if (!function_graph_enter_ops(old, ip, 0, parent, gops))

So this should be

if (!function_graph_enter_ops(*parent, ip, 0, parent, gops))

Thanks, 

-- 
Masami Hiramatsu (Google) <mhiramat@kernel.org>