On Thu, Sep 21, 2017 at 03:11:43PM +0000, Mathieu Desnoyers wrote: > ----- On Sep 21, 2017, at 8:13 AM, Peter Zijlstra peterz@xxxxxxxxxxxxx wrote: > > > On Mon, Sep 18, 2017 at 06:36:47PM -0400, Mathieu Desnoyers wrote: > >> @@ -3373,6 +3362,7 @@ static void __sched notrace __schedule(bool preempt) > >> > >> /* Also unlocks the rq: */ > >> rq = context_switch(rq, prev, next, &rf); > >> + membarrier_arch_sched_in(prev, next); > > > > That's wrong iirc; we just switched stacks, you cannot use @prev and > > @next. > > Yes, it did indeed explode spectacularly at boot in testing. RFC v3 fixes that. Good to hear that there is a useful test. ;-) Thanx, Paul > Thanks, > > Mathieu > > > > > >> } else { > >> rq->clock_update_flags &= ~(RQCF_ACT_SKIP|RQCF_REQ_SKIP); > > > rq_unlock_irq(rq, &rf); > > -- > Mathieu Desnoyers > EfficiOS Inc. > http://www.efficios.com >