On Tue, 10 Mar 2020 08:47:49 -0700 "Paul E. McKenney" <paulmck@xxxxxxxxxx> wrote: > On Tue, Mar 10, 2020 at 03:05:57PM +0000, David Laight wrote: > > From: Marco Elver > > > Sent: 10 March 2020 14:10 > > ... > > > FWIW, for writes we're already being quite generous, in that plain > > > aligned writes up to word-size are assumed to be "atomic" with the > > > default (conservative) config, i.e. marking such writes is optional. > > > Although, that's a generous assumption that is not always guaranteed > > > to hold (https://lore.kernel.org/lkml/20190821103200.kpufwtviqhpbuv2n@willie-the-truck/). > > > > Remind me to start writing everything in assembler. > > Been there, done that. :-/ > > > That and to mark all structure members 'volatile'. > > Indeed. READ_ONCE() and WRITE_ONCE() get this same effect, but without > pessimizing non-concurrent accesses to those same members. Plus KCSAN > knows about READ_ONCE(), WRITE_ONCE(), and also volatile members. > So I take it from all the above that we should do this. Did anyone actually review the code? :)
