Re: [RFC PATCH 18/32] function_graph: Fix to initalize ftrace_ops for fgraph with ftrace_graph_func

[Google]

On Mon,  6 Nov 2023 01:10:10 +0900
"Masami Hiramatsu (Google)" <mhiramat@xxxxxxxxxx> wrote:

> From: Masami Hiramatsu (Google) <mhiramat@xxxxxxxxxx>
> 
> Fix to initialize the ftrace_ops of fgraph_ops with ftrace_graph_func
> instead of ftrace_stub.

I've changed this, because fprobe entry handler is not called via
fgraph without this. But maybe I have to set correct gops->ops.func
after init?

Thank you,

> 
> Signed-off-by: Masami Hiramatsu (Google) <mhiramat@xxxxxxxxxx>
> ---
>  kernel/trace/fgraph.c |    4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/kernel/trace/fgraph.c b/kernel/trace/fgraph.c
> index 597250bd30dc..858fb73440ec 100644
> --- a/kernel/trace/fgraph.c
> +++ b/kernel/trace/fgraph.c
> @@ -872,7 +872,7 @@ unsigned long ftrace_graph_ret_addr(struct task_struct *task, int *idx,
>  void fgraph_init_ops(struct ftrace_ops *dst_ops,
>  		     struct ftrace_ops *src_ops)
>  {
> -	dst_ops->func = ftrace_stub;
> +	dst_ops->func = ftrace_graph_func;
>  	dst_ops->flags = FTRACE_OPS_FL_PID | FTRACE_OPS_FL_STUB;
>  
>  #ifdef FTRACE_GRAPH_TRAMP_ADDR
> @@ -1120,7 +1120,7 @@ int register_ftrace_graph(struct fgraph_ops *gops)
>  
>  	if (!gops->ops.func) {
>  		gops->ops.flags |= FTRACE_OPS_FL_STUB;
> -		gops->ops.func = ftrace_stub;
> +		gops->ops.func = ftrace_graph_func;
>  #ifdef FTRACE_GRAPH_TRAMP_ADDR
>  		gops->ops.trampoline = FTRACE_GRAPH_TRAMP_ADDR;
>  #endif
> 


-- 
Masami Hiramatsu (Google) <mhiramat@xxxxxxxxxx>