cgroup: s/for_each_subsys()/for_each_root_subsys()/

for_each_subsys() walks over subsystems attached to a hierarchy and
we're gonna add iterators which walk over all available subsystems.
Rename for_each_subsys() to for_each_root_subsys() so that it's more
appropriately named and for_each_subsys() can be used to iterate all
subsystems.

While at it, remove unnecessary underbar prefix from macro arguments,
put them inside parentheses, and adjust indentation for the two
for_each_*() macros.

This patch is purely cosmetic.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>

diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index c8d3175c429ca7d6c35d24882c5537aec8cbe57c..605cb13a1574a41a207a329afdbd6c8538d6f38f 100644 (file)
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -259,16 +259,13 @@ static int notify_on_release(const struct cgroup *cgrp)
        return test_bit(CGRP_NOTIFY_ON_RELEASE, &cgrp->flags);
 }
 
-/*
- * for_each_subsys() allows you to iterate on each subsystem attached to
- * an active hierarchy
- */
-#define for_each_subsys(_root, _ss) \
-list_for_each_entry(_ss, &_root->subsys_list, sibling)
+/* iterate each subsystem attached to a hierarchy */
+#define for_each_root_subsys(root, ss)                                 \
+       list_for_each_entry((ss), &(root)->subsys_list, sibling)
 
-/* for_each_active_root() allows you to iterate across the active hierarchies */
-#define for_each_active_root(_root) \
-list_for_each_entry(_root, &cgroup_roots, root_list)
+/* iterate across the active hierarchies */
+#define for_each_active_root(root)                                     \
+       list_for_each_entry((root), &cgroup_roots, root_list)
 
 static inline struct cgroup *__d_cgrp(struct dentry *dentry)
 {
@@ -828,7 +825,7 @@ static void cgroup_free_fn(struct work_struct *work)
        /*
         * Release the subsystem state objects.
         */
-       for_each_subsys(cgrp->root, ss)
+       for_each_root_subsys(cgrp->root, ss)
                ss->css_free(cgrp);
 
        cgrp->root->number_of_cgroups--;
@@ -944,7 +941,7 @@ static void cgroup_clear_directory(struct dentry *dir, bool base_files,
        struct cgroup *cgrp = __d_cgrp(dir);
        struct cgroup_subsys *ss;
 
-       for_each_subsys(cgrp->root, ss) {
+       for_each_root_subsys(cgrp->root, ss) {
                struct cftype_set *set;
                if (!test_bit(ss->subsys_id, &subsys_mask))
                        continue;
@@ -1078,7 +1075,7 @@ static int cgroup_show_options(struct seq_file *seq, struct dentry *dentry)
        struct cgroup_subsys *ss;
 
        mutex_lock(&cgroup_root_mutex);
-       for_each_subsys(root, ss)
+       for_each_root_subsys(root, ss)
                seq_printf(seq, ",%s", ss->name);
        if (root->flags & CGRP_ROOT_SANE_BEHAVIOR)
                seq_puts(seq, ",sane_behavior");
@@ -2054,7 +2051,7 @@ static int cgroup_attach_task(struct cgroup *cgrp, struct task_struct *tsk,
        /*
         * step 1: check that we can legitimately attach to the cgroup.
         */
-       for_each_subsys(root, ss) {
+       for_each_root_subsys(root, ss) {
                if (ss->can_attach) {
                        retval = ss->can_attach(cgrp, &tset);
                        if (retval) {
@@ -2091,7 +2088,7 @@ static int cgroup_attach_task(struct cgroup *cgrp, struct task_struct *tsk,
        /*
         * step 4: do subsystem attach callbacks.
         */
-       for_each_subsys(root, ss) {
+       for_each_root_subsys(root, ss) {
                if (ss->attach)
                        ss->attach(cgrp, &tset);
        }
@@ -2111,7 +2108,7 @@ out_put_css_set_refs:
        }
 out_cancel_attach:
        if (retval) {
-               for_each_subsys(root, ss) {
+               for_each_root_subsys(root, ss) {
                        if (ss == failed_ss)
                                break;
                        if (ss->cancel_attach)
@@ -4137,7 +4134,7 @@ static int cgroup_populate_dir(struct cgroup *cgrp, bool base_files,
        }
 
        /* process cftsets of each subsystem */
-       for_each_subsys(cgrp->root, ss) {
+       for_each_root_subsys(cgrp->root, ss) {
                struct cftype_set *set;
                if (!test_bit(ss->subsys_id, &subsys_mask))
                        continue;
@@ -4147,7 +4144,7 @@ static int cgroup_populate_dir(struct cgroup *cgrp, bool base_files,
        }
 
        /* This cgroup is ready now */
-       for_each_subsys(cgrp->root, ss) {
+       for_each_root_subsys(cgrp->root, ss) {
                struct cgroup_subsys_state *css = cgrp->subsys[ss->subsys_id];
                /*
                 * Update id->css pointer and make this css visible from
@@ -4294,7 +4291,7 @@ static long cgroup_create(struct cgroup *parent, struct dentry *dentry,
        if (test_bit(CGRP_CPUSET_CLONE_CHILDREN, &parent->flags))
                set_bit(CGRP_CPUSET_CLONE_CHILDREN, &cgrp->flags);
 
-       for_each_subsys(root, ss) {
+       for_each_root_subsys(root, ss) {
                struct cgroup_subsys_state *css;
 
                css = ss->css_alloc(cgrp);
@@ -4333,14 +4330,14 @@ static long cgroup_create(struct cgroup *parent, struct dentry *dentry,
        root->number_of_cgroups++;
 
        /* each css holds a ref to the cgroup's dentry */
-       for_each_subsys(root, ss)
+       for_each_root_subsys(root, ss)
                dget(dentry);
 
        /* hold a ref to the parent's dentry */
        dget(parent->dentry);
 
        /* creation succeeded, notify subsystems */
-       for_each_subsys(root, ss) {
+       for_each_root_subsys(root, ss) {
                err = online_css(ss, cgrp);
                if (err)
                        goto err_destroy;
@@ -4365,7 +4362,7 @@ static long cgroup_create(struct cgroup *parent, struct dentry *dentry,
        return 0;
 
 err_free_all:
-       for_each_subsys(root, ss) {
+       for_each_root_subsys(root, ss) {
                struct cgroup_subsys_state *css = cgrp->subsys[ss->subsys_id];
 
                if (css) {
@@ -4478,7 +4475,7 @@ static int cgroup_destroy_locked(struct cgroup *cgrp)
         * be killed.
         */
        atomic_set(&cgrp->css_kill_cnt, 1);
-       for_each_subsys(cgrp->root, ss) {
+       for_each_root_subsys(cgrp->root, ss) {
                struct cgroup_subsys_state *css = cgrp->subsys[ss->subsys_id];
 
                /*
@@ -4552,7 +4549,7 @@ static void cgroup_offline_fn(struct work_struct *work)
         * css_tryget() is guaranteed to fail now.  Tell subsystems to
         * initate destruction.
         */
-       for_each_subsys(cgrp->root, ss)
+       for_each_root_subsys(cgrp->root, ss)
                offline_css(ss, cgrp);
 
        /*
@@ -4562,7 +4559,7 @@ static void cgroup_offline_fn(struct work_struct *work)
         * whenever that may be, the extra dentry ref is put so that dentry
         * destruction happens only after all css's are released.
         */
-       for_each_subsys(cgrp->root, ss)
+       for_each_root_subsys(cgrp->root, ss)
                css_put(cgrp->subsys[ss->subsys_id]);
 
        /* delete this cgroup from parent->children */
@@ -4967,7 +4964,7 @@ int proc_cgroup_show(struct seq_file *m, void *v)
                int count = 0;
 
                seq_printf(m, "%d:", root->hierarchy_id);
-               for_each_subsys(root, ss)
+               for_each_root_subsys(root, ss)
                        seq_printf(m, "%s%s", count++ ? "," : "", ss->name);
                if (strlen(root->name))
                        seq_printf(m, "%sname=%s", count ? "," : "",