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>

diff --git a/kernel/tracepoint.c b/kernel/tracepoint.c
index 685c50ae63000a65f2dc0ca4c6fe8280088d8646..671b134573876d7ab5f8c3b2f1b8722b909c1201 100644 (file)
--- 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))