> On Jul 18, 2023, at 9:16 PM, NeilBrown <neilb@xxxxxxx> wrote: > > On Tue, 18 Jul 2023, Chuck Lever wrote: >> On Tue, Jul 18, 2023 at 04:38:08PM +1000, NeilBrown wrote: >>> No callers of svc_pool_wake_idle_thread() care which thread was woken - >>> except one that wants to trace the wakeup. For now we drop that >>> tracepoint. >> >> That's an important tracepoint, IMO. >> >> It might be better to have svc_pool_wake_idle_thread() return void >> right from it's introduction, and move the tracepoint into that >> function. I can do that and respin if you agree. > > Mostly I agree. > > It isn't clear to me how you would handle trace_svc_xprt_enqueue(), > as there would be no code that can see both the trigger xprt, and the > woken rqst. > > I also wonder if having the trace point when the wake-up is requested > makes any sense, as there is no guarantee that thread with handle that > xprt. > > Maybe the trace point should report when the xprt is dequeued. i.e. > maybe trace_svc_pool_awoken() should report the pid, and we could have > trace_svc_xprt_enqueue() only report the xprt, not the rqst. I'll come up with something that rearranges the tracepoints so that svc_pool_wake_idle_thread() can return void. svc_pool_wake_idle_thread() can save the waker's PID in svc_rqst somewhere, for example. The dequeue tracepoint can then report that (if it's still interesting when we're all done with this work). -- Chuck Lever
