keyring: Remove now-redundant smp_read_barrier_depends()

Now that the associative-array library properly heads dependency chains,
the various smp_read_barrier_depends() calls in security/keys/keyring.c
are no longer needed.  This commit therefore removes them.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: David Howells <dhowells@redhat.com>
Cc: "Serge E. Hallyn" <serge@hallyn.com>
Cc: <keyrings@vger.kernel.org>
Cc: <linux-security-module@vger.kernel.org>
Reviewed-by: James Morris <james.l.morris@oracle.com>
This commit is contained in:
Paul E. McKenney 2017-10-09 12:19:27 -07:00
parent 4be2b04e43
commit d963007c72

View File

@ -713,7 +713,6 @@ descend_to_keyring:
* doesn't contain any keyring pointers.
*/
shortcut = assoc_array_ptr_to_shortcut(ptr);
smp_read_barrier_depends();
if ((shortcut->index_key[0] & ASSOC_ARRAY_FAN_MASK) != 0)
goto not_this_keyring;
@ -723,8 +722,6 @@ descend_to_keyring:
}
node = assoc_array_ptr_to_node(ptr);
smp_read_barrier_depends();
ptr = node->slots[0];
if (!assoc_array_ptr_is_meta(ptr))
goto begin_node;
@ -736,7 +733,6 @@ descend_to_node:
kdebug("descend");
if (assoc_array_ptr_is_shortcut(ptr)) {
shortcut = assoc_array_ptr_to_shortcut(ptr);
smp_read_barrier_depends();
ptr = READ_ONCE(shortcut->next_node);
BUG_ON(!assoc_array_ptr_is_node(ptr));
}
@ -744,7 +740,6 @@ descend_to_node:
begin_node:
kdebug("begin_node");
smp_read_barrier_depends();
slot = 0;
ascend_to_node:
/* Go through the slots in a node */
@ -792,14 +787,12 @@ ascend_to_node:
if (ptr && assoc_array_ptr_is_shortcut(ptr)) {
shortcut = assoc_array_ptr_to_shortcut(ptr);
smp_read_barrier_depends();
ptr = READ_ONCE(shortcut->back_pointer);
slot = shortcut->parent_slot;
}
if (!ptr)
goto not_this_keyring;
node = assoc_array_ptr_to_node(ptr);
smp_read_barrier_depends();
slot++;
/* If we've ascended to the root (zero backpointer), we must have just