On Mon, 07 Sep 2020 13:44:19 -0400 fche@xxxxxxxxxx (Frank Ch. Eigler) wrote: > Masami Hiramatsu <mhiramat@xxxxxxxxxx> writes: > > > Sorry, for noticing this point, I Cc'd to systemtap. Is systemtap taking > > care of spinlock too? > > On PRREMPT_RT configurations, systemtap uses the raw_spinlock_t > types/functions, to keep its probe handlers as atomic as we can make them. OK, if the lock is only used in the probe handlers, there should be no problem. Even if a probe hits in the NMI which happens in another kprobe handler, the probe does not call its handler (because we don't support nested kprobes* yet). But maybe you'll get warnings if you enable the lockdep. * https://lkml.kernel.org/r/158894789510.14896.13461271606820304664.stgit@devnote2 It seems that we need more work for the nested kprobes. Thank you, -- Masami Hiramatsu <mhiramat@xxxxxxxxxx>
