Re: [PATCH 02/11] locking, rwsem: drop explicit memory barriers

2016-04-04 Thread Michal Hocko
On Fri 01-04-16 18:17:53, Davidlohr Bueso wrote: [...] > I think we can actually get rid of these files altogether. While I > don't know the archs, it does not appear to be implementing any kind > of workaround/optimization, which is obviously the whole purpose of > defining per-arch rwsem internal

Re: [PATCH 02/11] locking, rwsem: drop explicit memory barriers

2016-04-01 Thread Davidlohr Bueso
On Fri, 01 Apr 2016, Michal Hocko wrote: From: Michal Hocko sh and xtensa seem to be the only architectures which use explicit memory barriers for rw_semaphore operations even though they are not really needed because there is the full memory barrier is always implied by atomic_{inc,dec,add,su