Linux 3.2.12

[pandora-kernel.git] / kernel / cgroup.c

diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index 453100a..cdc0354 100644 (file)
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -1175,10 +1175,10 @@ static int parse_cgroupfs_options(char *data, struct cgroup_sb_opts *opts)
 
        /*
         * If the 'all' option was specified select all the subsystems,
-        * otherwise 'all, 'none' and a subsystem name options were not
-        * specified, let's default to 'all'
+        * otherwise if 'none', 'name=' and a subsystem name options
+        * were not specified, let's default to 'all'
         */
-       if (all_ss || (!all_ss && !one_ss && !opts->none)) {
+       if (all_ss || (!one_ss && !opts->none && !opts->name)) {
                for (i = 0; i < CGROUP_SUBSYS_COUNT; i++) {
                        struct cgroup_subsys *ss = subsys[i];
                        if (ss == NULL)
@@ -2027,7 +2027,7 @@ int cgroup_attach_proc(struct cgroup *cgrp, struct task_struct *leader)
                goto out_free_group_list;
 
        /* prevent changes to the threadgroup list while we take a snapshot. */
-       rcu_read_lock();
+       read_lock(&tasklist_lock);
        if (!thread_group_leader(leader)) {
                /*
                 * a race with de_thread from another thread's exec() may strip
@@ -2036,7 +2036,7 @@ int cgroup_attach_proc(struct cgroup *cgrp, struct task_struct *leader)
                 * throw this task away and try again (from cgroup_procs_write);
                 * this is "double-double-toil-and-trouble-check locking".
                 */
-               rcu_read_unlock();
+               read_unlock(&tasklist_lock);
                retval = -EAGAIN;
                goto out_free_group_list;
        }
@@ -2057,7 +2057,7 @@ int cgroup_attach_proc(struct cgroup *cgrp, struct task_struct *leader)
        } while_each_thread(leader, tsk);
        /* remember the number of threads in the array for later. */
        group_size = i;
-       rcu_read_unlock();
+       read_unlock(&tasklist_lock);
 
        /*
         * step 1: check that we can legitimately attach to the cgroup.
@@ -2098,11 +2098,6 @@ int cgroup_attach_proc(struct cgroup *cgrp, struct task_struct *leader)
                        continue;
                /* get old css_set pointer */
                task_lock(tsk);
-               if (tsk->flags & PF_EXITING) {
-                       /* ignore this task if it's going away */
-                       task_unlock(tsk);
-                       continue;
-               }
                oldcg = tsk->cgroups;
                get_css_set(oldcg);
                task_unlock(tsk);
@@ -2135,14 +2130,17 @@ int cgroup_attach_proc(struct cgroup *cgrp, struct task_struct *leader)
                oldcgrp = task_cgroup_from_root(tsk, root);
                if (cgrp == oldcgrp)
                        continue;
-               /* attach each task to each subsystem */
-               for_each_subsys(root, ss) {
-                       if (ss->attach_task)
-                               ss->attach_task(cgrp, tsk);
-               }
                /* if the thread is PF_EXITING, it can just get skipped. */
                retval = cgroup_task_migrate(cgrp, oldcgrp, tsk, true);
-               BUG_ON(retval != 0 && retval != -ESRCH);
+               if (retval == 0) {
+                       /* attach each task to each subsystem */
+                       for_each_subsys(root, ss) {
+                               if (ss->attach_task)
+                                       ss->attach_task(cgrp, tsk);
+                       }
+               } else {
+                       BUG_ON(retval != -ESRCH);
+               }
        }
        /* nothing is sensitive to fork() after this point. */
 
@@ -4880,9 +4878,9 @@ void free_css_id(struct cgroup_subsys *ss, struct cgroup_subsys_state *css)
 
        rcu_assign_pointer(id->css, NULL);
        rcu_assign_pointer(css->id, NULL);
-       spin_lock(&ss->id_lock);
+       write_lock(&ss->id_lock);
        idr_remove(&ss->idr, id->id);
-       spin_unlock(&ss->id_lock);
+       write_unlock(&ss->id_lock);
        kfree_rcu(id, rcu_head);
 }
 EXPORT_SYMBOL_GPL(free_css_id);
@@ -4908,10 +4906,10 @@ static struct css_id *get_new_cssid(struct cgroup_subsys *ss, int depth)
                error = -ENOMEM;
                goto err_out;
        }
-       spin_lock(&ss->id_lock);
+       write_lock(&ss->id_lock);
        /* Don't use 0. allocates an ID of 1-65535 */
        error = idr_get_new_above(&ss->idr, newid, 1, &myid);
-       spin_unlock(&ss->id_lock);
+       write_unlock(&ss->id_lock);
 
        /* Returns error when there are no free spaces for new ID.*/
        if (error) {
@@ -4926,9 +4924,9 @@ static struct css_id *get_new_cssid(struct cgroup_subsys *ss, int depth)
        return newid;
 remove_idr:
        error = -ENOSPC;
-       spin_lock(&ss->id_lock);
+       write_lock(&ss->id_lock);
        idr_remove(&ss->idr, myid);
-       spin_unlock(&ss->id_lock);
+       write_unlock(&ss->id_lock);
 err_out:
        kfree(newid);
        return ERR_PTR(error);
@@ -4940,7 +4938,7 @@ static int __init_or_module cgroup_init_idr(struct cgroup_subsys *ss,
 {
        struct css_id *newid;
 
-       spin_lock_init(&ss->id_lock);
+       rwlock_init(&ss->id_lock);
        idr_init(&ss->idr);
 
        newid = get_new_cssid(ss, 0);
@@ -5035,9 +5033,9 @@ css_get_next(struct cgroup_subsys *ss, int id,
                 * scan next entry from bitmap(tree), tmpid is updated after
                 * idr_get_next().
                 */
-               spin_lock(&ss->id_lock);
+               read_lock(&ss->id_lock);
                tmp = idr_get_next(&ss->idr, &tmpid);
-               spin_unlock(&ss->id_lock);
+               read_unlock(&ss->id_lock);
 
                if (!tmp)
                        break;