On Thu, Jul 13, 2017 at 08:23:33PM +0900, Byungchul Park wrote: > On Thu, Jul 13, 2017 at 8:12 PM, Peter Zijlstra <pet...@infradead.org> wrote: > > On Thu, Jul 13, 2017 at 12:29:05PM +0200, Peter Zijlstra wrote: > >> On Thu, Jul 13, 2017 at 07:09:53PM +0900, Byungchul Park wrote: > >> > On Thu, Jul 13, 2017 at 11:50:52AM +0200, Peter Zijlstra wrote: > >> > > wait_for_completion(&C); > >> > > atomic_inc_return(); > >> > > > >> > > mutex_lock(A1); > >> > > mutex_unlock(A1); > >> > > > >> > > > >> > > <IRQ> > >> > > spin_lock(B1); > >> > > spin_unlock(B1); > >> > > > >> > > ... > >> > > > >> > > spin_lock(B64); > >> > > spin_unlock(B64); > >> > > </IRQ> > >> > > > >> > > > > > > Also consider the alternative: > > > > <IRQ> > > spin_lock(D); > > spin_unlock(D); > > > > complete(&C); > > </IRQ> > > > > in which case the context test will also not work. > > Context tests are done on xhlock with the release context, _not_ > acquisition context. For example, spin_lock(D) and complete(&C) are > in the same context, so the test would pass in this example.
Something wrong?
