David Laight <da...@l8s.co.uk> wrote: > > Also: > > > > + if (dtrace_vtime_active) { > > + (*dtrace_vtime_switch_func)(newl); > > + } > > > > It is worth to give a separate cache line for dtrace_vtime_active and > > use __predict_false(). > > __predict_false() yes, but separating things into their own cache lines > is probably a pessimalisation - mainly because it increases the working > set (of cache lines) of the code.
Why it would pessimise, since it needs to read that cache line anyway? Also, note that dtrace_vtime_switch_func and dtrace_vtime_active can share the same cache line. -- Mindaugas