[ added Mathieu ] On Mon, 9 Oct 2017 17:22:45 -0700 "Paul E. McKenney" <[email protected]> wrote:
> The comment in tracepoint_add_func() mentions smp_read_barrier_depends(), > whose use should be quite restricted. This commit updates the comment > to instead mention the smp_store_release() and rcu_dereference_sched() > that the current code actually uses. > > Signed-off-by: Paul E. McKenney <[email protected]> > Cc: Ingo Molnar <[email protected]> > Cc: Steven Rostedt <[email protected]> Acked-by: Steven Rostedt (VMware) <[email protected]> -- Steve > --- > kernel/tracepoint.c | 9 ++++----- > 1 file changed, 4 insertions(+), 5 deletions(-) > > diff --git a/kernel/tracepoint.c b/kernel/tracepoint.c > index 685c50ae6300..671b13457387 100644 > --- a/kernel/tracepoint.c > +++ b/kernel/tracepoint.c > @@ -212,11 +212,10 @@ static int tracepoint_add_func(struct tracepoint *tp, > } > > /* > - * rcu_assign_pointer has a smp_wmb() which makes sure that the new > - * probe callbacks array is consistent before setting a pointer to it. > - * This array is referenced by __DO_TRACE from > - * include/linux/tracepoints.h. A matching smp_read_barrier_depends() > - * is used. > + * rcu_assign_pointer has as smp_store_release() which makes sure > + * that the new probe callbacks array is consistent before setting > + * a pointer to it. This array is referenced by __DO_TRACE from > + * include/linux/tracepoint.h using rcu_dereference_sched(). > */ > rcu_assign_pointer(tp->funcs, tp_funcs); > if (!static_key_enabled(&tp->key))
