Messages in this thread | | | Date | Mon, 23 Jan 2023 12:34:37 -0500 | From | Alan Stern <> | Subject | Re: [PATCH] Fix data race in mark_rt_mutex_waiters |
| |
On Mon, Jan 23, 2023 at 08:40:14AM -0800, Paul E. McKenney wrote: > In the case, the value read is passed into cmpxchg_relaxed(), which > checks the value against memory. In this case, as Arjan noted, the only > compiler-and-silicon difference between data_race() and READ_ONCE() > is that use of data_race() might allow the compiler to do things like > tear the load, thus forcing the occasional spurious cmpxchg_relaxed() > failure.
Is it possible in theory for a torn load to cause a spurious cmpxchg_relaxed() success? Or would that not matter here?
Alan
| |