Merge branch 'regulator-4.20' into regulator-next

[linux-2.6-block.git] / kernel / cgroup / cgroup.c

diff --git a/kernel/cgroup/cgroup.c b/kernel/cgroup/cgroup.c
index 35cf3d71f8aaf4b7efcdc241953abe2108b58f6a..4a3dae2a8283041b46d2c9ff981a51a7d5c2563e 100644 (file)
--- a/kernel/cgroup/cgroup.c
+++ b/kernel/cgroup/cgroup.c
@@ -83,6 +83,9 @@ EXPORT_SYMBOL_GPL(cgroup_mutex);
 EXPORT_SYMBOL_GPL(css_set_lock);
 #endif
 
+DEFINE_SPINLOCK(trace_cgroup_path_lock);
+char trace_cgroup_path[TRACE_CGROUP_PATH_LEN];
+
 /*
  * Protects cgroup_idr and css_idr so that IDs can be released without
  * grabbing cgroup_mutex.
@@ -2638,7 +2641,7 @@ int cgroup_attach_task(struct cgroup *dst_cgrp, struct task_struct *leader,
        cgroup_migrate_finish(&mgctx);
 
        if (!ret)
-               trace_cgroup_attach_task(dst_cgrp, leader, threadgroup);
+               TRACE_CGROUP_PATH(attach_task, dst_cgrp, leader, threadgroup);
 
        return ret;
 }
@@ -2833,11 +2836,12 @@ restart:
 }
 
 /**
- * cgroup_save_control - save control masks of a subtree
+ * cgroup_save_control - save control masks and dom_cgrp of a subtree
  * @cgrp: root of the target subtree
  *
- * Save ->subtree_control and ->subtree_ss_mask to the respective old_
- * prefixed fields for @cgrp's subtree including @cgrp itself.
+ * Save ->subtree_control, ->subtree_ss_mask and ->dom_cgrp to the
+ * respective old_ prefixed fields for @cgrp's subtree including @cgrp
+ * itself.
  */
 static void cgroup_save_control(struct cgroup *cgrp)
 {
@@ -2847,6 +2851,7 @@ static void cgroup_save_control(struct cgroup *cgrp)
        cgroup_for_each_live_descendant_pre(dsct, d_css, cgrp) {
                dsct->old_subtree_control = dsct->subtree_control;
                dsct->old_subtree_ss_mask = dsct->subtree_ss_mask;
+               dsct->old_dom_cgrp = dsct->dom_cgrp;
        }
 }
 
@@ -2872,11 +2877,12 @@ static void cgroup_propagate_control(struct cgroup *cgrp)
 }
 
 /**
- * cgroup_restore_control - restore control masks of a subtree
+ * cgroup_restore_control - restore control masks and dom_cgrp of a subtree
  * @cgrp: root of the target subtree
  *
- * Restore ->subtree_control and ->subtree_ss_mask from the respective old_
- * prefixed fields for @cgrp's subtree including @cgrp itself.
+ * Restore ->subtree_control, ->subtree_ss_mask and ->dom_cgrp from the
+ * respective old_ prefixed fields for @cgrp's subtree including @cgrp
+ * itself.
  */
 static void cgroup_restore_control(struct cgroup *cgrp)
 {
@@ -2886,6 +2892,7 @@ static void cgroup_restore_control(struct cgroup *cgrp)
        cgroup_for_each_live_descendant_post(dsct, d_css, cgrp) {
                dsct->subtree_control = dsct->old_subtree_control;
                dsct->subtree_ss_mask = dsct->old_subtree_ss_mask;
+               dsct->dom_cgrp = dsct->old_dom_cgrp;
        }
 }
 
@@ -3193,6 +3200,8 @@ static int cgroup_enable_threaded(struct cgroup *cgrp)
 {
        struct cgroup *parent = cgroup_parent(cgrp);
        struct cgroup *dom_cgrp = parent->dom_cgrp;
+       struct cgroup *dsct;
+       struct cgroup_subsys_state *d_css;
        int ret;
 
        lockdep_assert_held(&cgroup_mutex);
@@ -3222,12 +3231,13 @@ static int cgroup_enable_threaded(struct cgroup *cgrp)
         */
        cgroup_save_control(cgrp);
 
-       cgrp->dom_cgrp = dom_cgrp;
+       cgroup_for_each_live_descendant_pre(dsct, d_css, cgrp)
+               if (dsct == cgrp || cgroup_is_threaded(dsct))
+                       dsct->dom_cgrp = dom_cgrp;
+
        ret = cgroup_apply_control(cgrp);
        if (!ret)
                parent->nr_threaded_children++;
-       else
-               cgrp->dom_cgrp = cgrp;
 
        cgroup_finalize_control(cgrp, ret);
        return ret;
@@ -4636,7 +4646,7 @@ static void css_release_work_fn(struct work_struct *work)
                struct cgroup *tcgrp;
 
                /* cgroup release path */
-               trace_cgroup_release(cgrp);
+               TRACE_CGROUP_PATH(release, cgrp);
 
                if (cgroup_on_dfl(cgrp))
                        cgroup_rstat_flush(cgrp);
@@ -4979,7 +4989,7 @@ int cgroup_mkdir(struct kernfs_node *parent_kn, const char *name, umode_t mode)
        if (ret)
                goto out_destroy;
 
-       trace_cgroup_mkdir(cgrp);
+       TRACE_CGROUP_PATH(mkdir, cgrp);
 
        /* let's create and online css's */
        kernfs_activate(kn);
@@ -5167,9 +5177,8 @@ int cgroup_rmdir(struct kernfs_node *kn)
                return 0;
 
        ret = cgroup_destroy_locked(cgrp);
-
        if (!ret)
-               trace_cgroup_rmdir(cgrp);
+               TRACE_CGROUP_PATH(rmdir, cgrp);
 
        cgroup_kn_unlock(kn);
        return ret;