On Wed, Feb 7, 2018 at 2:21 PM, Taylor R Campbell <campbell+netbsd-tech-k...@mumble.net> wrote: >> Date: Wed, 7 Feb 2018 14:14:35 +0900 >> From: Ryota Ozaki <ozak...@netbsd.org> >> >> On Wed, Feb 7, 2018 at 2:55 AM, Taylor R Campbell >> <campbell+netbsd-tech-k...@mumble.net> wrote: >> >> Date: Tue, 6 Feb 2018 19:06:33 +0900 >> >> From: Ryota Ozaki <ozak...@netbsd.org> >> >> >> >> So I think we should do either: >> >> (1) fix rw_lock_held, or >> >> - probably it would be rw_read_held() || rw_write_held() >> >> (2) fix users of rw_lock_held. >> >> - it also would replace rw_lock_held with >> >> rw_read_held() || rw_write_held() >> >> >> >> I prefer (1) because I think there is no user of the current >> >> behavior that is difficult to use for users (it may be useful >> >> as an internal utility function though). >> > >> > I like (1) too, but check for Solaris compatibility? It is hard to >> > imagine that there are correct uses of the current semantics that are >> > not also correct uses of (1). >> >> https://docs.oracle.com/cd/E36784_01/html/E36886/rwlock-9f.html >> >> They seem to have only rw_read_locked that is compatible to our >> rw_read_held. > > Looks to me like rw_read_locked is actually more like: > > KASSERT(rw_read_held(l) || rw_write_held(l)); > return rw_read_held(l); > > or > > KASSERT(rw_read_held(l) || rw_write_held(l)); > return !rw_write_held(l);
Oops. Yes, I misunderstood rw_read_held. ozaki-r
