tracepoint: Remove smp_read_barrier_depends() from comment

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 <paulmck@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Acked-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

1 files 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))