Re: [PATCH v18 01/17] fgraph: Pass ftrace_regs to entryfunc

Steven Rostedt
2024-11-01T10:49:30Z

On Fri, 1 Nov 2024 10:51:02 +0900
Masami Hiramatsu (Google) <mhiramat@kernel.org> wrote:

> Ah, good catch! It should put the flag only when HAVE_DYNAMIC_FTRACE_WITH_ARGS
> is enabled.
>
> static struct ftrace_ops graph_ops = {
> .func = ftrace_graph_func,
> #ifdef CONFIG_DYNAMIC_FTRACE_WITH_ARGS
> .flags = FTRACE_OPS_GRAPH_STUB | FTRACE_OPS_FL_SAVE_ARGS,
> #elif defined(CONFIG_DYNAMIC_FTRACE_WITH_ARGS)
> .flags = FTRACE_OPS_GRAPH_STUB | FTRACE_OPS_FL_SAVE_REGS,
> #else
> .flags = FTRACE_OPS_GRAPH_STUB,
> #endif
>
> This will save fregs or regs or NULL according to the configuration.
>

Please do not add that to the C code. It's really ugly. Just correct the
comment. Note, FTRACE_OPS_FL_SAVE_ARGS is already dynamic by configuration:

#ifndef CONFIG_DYNAMIC_FTRACE_WITH_ARGS
#define FTRACE_OPS_FL_SAVE_ARGS FTRACE_OPS_FL_SAVE_REGS
#else
#define FTRACE_OPS_FL_SAVE_ARGS 0
#endif

I'm a bit confused at what you are trying to achieve here.

-- Steve