On Sat, 30 Mar 2024 11:18:29 +0800 梦龙董 <dongmenglong.8@xxxxxxxxxxxxx> wrote: > > If you really want to have thousands of functions, why not just register it > > with ftrace itself. It will give you the arguments via the ftrace_regs > > structure. Can't you just register a program as the callback? > > > > Ennn...I don't understand. The main purpose for > me to use TRACING is: > > 1. we can directly access the memory, which is more > efficient. I'm not sure what you mean by the above. Access what memory? > 2. we can obtain the function args in FEXIT, which > kretprobe can't do it. And this is the main reason. I didn't mention kretprobe. If you need access to the exit of the function, you can use Masami's fgraph update. fentry -> ftrace_trampoline -> your_code For fgraph: fentry -> ftrace_trampoline -> fgraph [sets up return call] -> your_entry_code function ret -> fgraph_ret_handler -> your_exit_code And you will be able to pass data from the entry to the exit code, including parameters. -- Steve
