On Wed, 4 Oct 2017 12:41:01 +0200 Ingo Molnar <[email protected]> wrote:
> > * Masami Hiramatsu <[email protected]> wrote: > > > Hmm, actually we can not disable jprobe, that has no separate Kconfig. > > So we need to introduce new kconfig for that. > > > > And, there are several network protocols using jprobe to trace events. > > (e.g. NET_DCCPPROBE and NET_TCPPROBE) > > I think they need to migrate to trace-event at first. > > > > So, how about below idea? > > > > 1. Introduce CONFIG_JPROBE_API which only separate jprobe general parts > > (no arch dependent code involves) and make it default n. > > 2. Mark break_handler and jprobe APIs deprecated so that no new user comes > > up. > > 3. migrate in-kernel jprobe user to trace-event or ftrace. > > (may take some time) > > So my suggestion would be to just return from register_jprobe() and don't > register > anything. with CONFIG_JPROBE_API=n, is that right? > Yes, there are usecases of jprobes in the kernel, but they all look > pretty ancient and unused. Hmm, in that case, should we also remove those users? If we disable such way those features are just useless. > > So let's try this for -next and see whether anyone has a real usecase. And no > Kconfig and deprecation messages - those don't really work in practice - just > disable the functionality and force people to (trivially) modify the source > if > they want to re-enable it. So you mean I don't have to change those usecases, just let them do. > > If this is fine for a single release then we can just remove it all: > > > 4. after that, we can completely remove jprobe which will be a series for > > all archs. (or just one big patch?) > > we want a series of patches - but that's for later. OK :) Thank you, > > Thanks, > > Ingo -- Masami Hiramatsu <[email protected]>
