On 2019-08-23 23:10:14 [-0400], Joel Fernandes wrote: > On Fri, Aug 23, 2019 at 02:28:46PM -0500, Scott Wood wrote: > > On Fri, 2019-08-23 at 18:20 +0200, Sebastian Andrzej Siewior wrote: > > > > > > this looks like an ugly hack. This sleeping_lock_inc() is used where we > > > actually hold a sleeping lock and schedule() which is okay. But this > > > would mean we hold a RCU lock and schedule() anyway. Is that okay? > > > > Perhaps the name should be changed, but the concept is the same -- RT- > > specific sleeping which should be considered involuntary for the purpose of > > debug checks. Voluntary sleeping is not allowed in an RCU critical section > > because it will break the critical section on certain flavors of RCU, but > > that doesn't apply to the flavor used on RT. Sleeping for a long time in an > > RCU critical section would also be a bad thing, but that also doesn't apply > > here. > > I think the name should definitely be changed. At best, it is super confusing to > call it "sleeping_lock" for this scenario. In fact here, you are not even > blocking on a lock. > > Maybe "sleeping_allowed" or some such. The mechanism that is used here may change in future. I just wanted to make sure that from RCU's side it is okay to schedule here. > thanks, > > - Joel Sebastian
