On Fri, Apr 27, 2018 at 9:37 AM, Steven Rostedt <rost...@goodmis.org> wrote: > On Fri, 27 Apr 2018 09:30:05 -0700 > Joel Fernandes <joe...@google.com> wrote: > >> On Fri, Apr 27, 2018 at 7:47 AM, Steven Rostedt <rost...@goodmis.org> wrote: >> > On Fri, 27 Apr 2018 10:26:29 -0400 (EDT) >> > Mathieu Desnoyers <mathieu.desnoy...@efficios.com> wrote: >> > >> >> The general approach and the implementation look fine, except for >> >> one small detail: I would be tempted to explicitly disable preemption >> >> around the call to the tracepoint callback for the rcuidle variant, >> >> unless we plan to audit every tracer right away to remove any assumption >> >> that preemption is disabled in the callback implementation. >> > >> > I'm thinking that we do that audit. There shouldn't be many instances >> > of it. I like the idea that a tracepoint callback gets called with >> > preemption enabled. >> >> Here is the list of all callers of the _rcuidle : > > I was thinking of auditing who registers callbacks to any tracepoints.
Ok. If you feel strongly about this, I think for now I could also just wrap the callback execution with preempt_disable_notrace. And, when/if we get to doing the blocking callbacks work, we can considering keeping preempts on. thanks, - Joel