On Wed, Oct 11, 2017 at 10:06:31AM -0700, Paul E. McKenney wrote: > On Wed, Oct 11, 2017 at 06:54:05PM +0200, Peter Zijlstra wrote: > > On Wed, Oct 11, 2017 at 09:47:48AM -0700, Paul E. McKenney wrote: > > > Interesting. Do we currently have any dependencies headed by > > > this_cpu_read()? > > > > Nope, but almost, look for: cpufreq_update_util_data. > > This, you mean? > > data = rcu_dereference_sched(*this_cpu_ptr(&cpufreq_update_util_data)); > > True, a non-RCU dependency use case would want to use ACCESS_ONCE() > in the new regime. Right... s/ACCESS_ONCE()/READ_ONCE()/ Thanx, Paul
