On Fri, Sep 01, 2017 at 11:05:12AM +0900, Byungchul Park wrote: > On Thu, Aug 31, 2017 at 10:34:53AM +0200, Peter Zijlstra wrote: > > On Thu, Aug 31, 2017 at 05:15:01PM +0900, Byungchul Park wrote: > > > It's not important. Ok, check the following, instead: > > > > > > context X context Y > > > --------- --------- > > > wait_for_completion(C) > > > acquire(A) > > > release(A) > > > process_one_work() > > > acquire(B) > > > release(B) > > > work->fn() > > > complete(C) > > > > > > We don't need to lose C->A and C->B dependencies unnecessarily. > > > > I really can't be arsed about them. Its really only the first few works > > that will retain that dependency anyway, even if you were to retain > > them. > > Wrong. > > Every 'work' doing complete() for different classes of completion > variable suffers from losing valuable dependencies, every time, not > first few ones.
The moment you overrun the history array its gone. So yes, only the first few works will ever see them
