(Note that I also agree with Linus's opinion that this is like a debugger, since I already did it in perf-probe :)) On Sun, 4 Feb 2018 11:39:39 -0800 Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> wrote: > (Obviously it's not entirely black-and-white, but I do think there is > a pretty big difference between the two groups. And the first group > will obviously use the explicit trace points _too_, generally to > narrow down where they want to go with the function-based one). > > We'll see. Maybe I'm entirely wrong. But I'm hoping that the > function-based one will end up being helpful. BTW, if the function-based tracing is helpful for both of them, they can start using it back in 2010 because kprobe-based tracer already supported it. It was less announced, I must admit that I was lazy at that point. Also, since I moved usability effort on perf-probe, kprobe-based event syntax is not so funcy. "SyS_openat(int dfd, string path, x32 flags, x16 mode)" is equal to "p SyS_openat dfd=%di:x64 path=%si:string flags=%dx:x32 mode=%cx:x16" in kprobe probe definition syntax, but with perf-probe and CONFIG_DEBUG_INFO, perf probe -a 'sys_openat $params' will setup the event correctly. So, we need to clarify what will attract more "2nd group" people to function based events. E.g. the events for EXPORT_SYMBOL_GPL() symbols already defined and easily on/off. Thank you, -- Masami Hiramatsu <mhiramat@xxxxxxxxxx> -- To unsubscribe from this list: send the line "unsubscribe linux-trace-users" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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