On Fri 24-08-18 13:57:52, Christian König wrote: > Am 24.08.2018 um 13:52 schrieb Michal Hocko: > > On Fri 24-08-18 13:43:16, Christian König wrote: [...] > > > That won't work like this there might be multiple > > > invalidate_range_start()/invalidate_range_end() pairs open at the same time. > > > E.g. the lock might be taken recursively and that is illegal for a > > > rw_semaphore. > > I am not sure I follow. Are you saying that one invalidate_range might > > trigger another one from the same path? > > No, but what can happen is: > > invalidate_range_start(A,B); > invalidate_range_start(C,D); > ... > invalidate_range_end(C,D); > invalidate_range_end(A,B); > > Grabbing the read lock twice would be illegal in this case. I am sorry but I still do not follow. What is the context the two are called from? Can you give me an example. I simply do not see it in the code, mostly because I am not familiar with it. -- Michal Hocko SUSE Labs
