cgroup: use do_each_subsys_mask() where applicable

There are several places in cgroup_subtree_control_write() which can
use do_each_subsys_mask() instead of manual mask testing.  Use it.

No functional changes.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>

diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index 5d102980dc278d2c5f4059dde6c9a41d9d3a0d66..1e561bd990b9ad7599be8423c90bfbbd0b17d9d1 100644 (file)
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -3082,10 +3082,7 @@ static ssize_t cgroup_subtree_control_write(struct kernfs_open_file *of,
         * dependency.  An invisible css is made visible when the userland
         * explicitly enables it.
         */
-       for_each_subsys(ss, ssid) {
-               if (!(enable & (1 << ssid)))
-                       continue;
-
+       do_each_subsys_mask(ss, ssid, enable) {
                cgroup_for_each_live_child(child, cgrp) {
                        if (css_enable & (1 << ssid))
                                ret = create_css(child, ss,
@@ -3096,7 +3093,7 @@ static ssize_t cgroup_subtree_control_write(struct kernfs_open_file *of,
                        if (ret)
                                goto err_undo_css;
                }
-       }
+       } while_each_subsys_mask();
 
        /*
         * At this point, cgroup_e_css() results reflect the new csses
@@ -3115,10 +3112,7 @@ static ssize_t cgroup_subtree_control_write(struct kernfs_open_file *of,
         * state if it's made visible again later.  Controllers which may
         * be depended upon should provide ->css_reset() for this purpose.
         */
-       for_each_subsys(ss, ssid) {
-               if (!(disable & (1 << ssid)))
-                       continue;
-
+       do_each_subsys_mask(ss, ssid, disable) {
                cgroup_for_each_live_child(child, cgrp) {
                        struct cgroup_subsys_state *css = cgroup_css(child, ss);
 
@@ -3130,7 +3124,7 @@ static ssize_t cgroup_subtree_control_write(struct kernfs_open_file *of,
                                        ss->css_reset(css);
                        }
                }
-       }
+       } while_each_subsys_mask();
 
        kernfs_activate(cgrp->kn);
        ret = 0;
@@ -3142,10 +3136,7 @@ err_undo_css:
        cgrp->subtree_control = old_sc;
        cgrp->subtree_ss_mask = old_ss;
 
-       for_each_subsys(ss, ssid) {
-               if (!(enable & (1 << ssid)))
-                       continue;
-
+       do_each_subsys_mask(ss, ssid, enable) {
                cgroup_for_each_live_child(child, cgrp) {
                        struct cgroup_subsys_state *css = cgroup_css(child, ss);
 
@@ -3157,7 +3148,7 @@ err_undo_css:
                        else
                                css_clear_dir(css, NULL);
                }
-       }
+       } while_each_subsys_mask();
        goto out_unlock;
 }
 
@@ -4973,14 +4964,12 @@ static int cgroup_mkdir(struct kernfs_node *parent_kn, const char *name,
                goto out_destroy;
 
        /* let's create and online css's */
-       for_each_subsys(ss, ssid) {
-               if (parent->subtree_ss_mask & (1 << ssid)) {
-                       ret = create_css(cgrp, ss,
-                                        parent->subtree_control & (1 << ssid));
-                       if (ret)
-                               goto out_destroy;
-               }
-       }
+       do_each_subsys_mask(ss, ssid, parent->subtree_ss_mask) {
+               ret = create_css(cgrp, ss,
+                                parent->subtree_control & (1 << ssid));
+               if (ret)
+                       goto out_destroy;
+       } while_each_subsys_mask();
 
        /*
         * On the default hierarchy, a child doesn't automatically inherit