On Mon, 30 Jul 2018, Peter Zijlstra wrote: > On Mon, Jul 30, 2018 at 12:20:57PM +0200, Thomas Gleixner wrote: > > On Tue, 24 Jul 2018, Sebastian Andrzej Siewior wrote: > > > On 2018-07-23 18:13:48 [-0700], isaacm@xxxxxxxxxxxxxx wrote: > > > > Hi all, > > > Hi, > > > > > > > Are there any comments about this patch? > > > > > > I haven't look in detail at this but your new preempt_disable() makes > > > things unbalanced for the err != 0 case. > > > > It doesn't but that code is really an unreadable pile of ... > > --- > Subject: stop_machine: Reflow cpu_stop_queue_two_works() > > The code flow in cpu_stop_queue_two_works() is a little arcane; fix > this by lifting the preempt_disable() to the top to create more natural > nesting wrt the spinlocks and make the wake_up_q() and preempt_enable() > unconditional at the end. > > Furthermore, enable preemption in the -EDEADLK case, such that we > spin-wait with preemption enabled. > > Suggested-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx> > Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx> Thanks for cleaning that up! Reviewed-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
