/*
- * kernel/cgroup.c
- *
* Generic process-grouping system.
*
* Based originally on the cpuset system, extracted by Paul Menage
ROOT_NOPREFIX, /* mounted subsystems have no named prefix */
};
-inline int cgroup_is_releasable(const struct cgroup *cgrp)
+static int cgroup_is_releasable(const struct cgroup *cgrp)
{
const int bits =
(1 << CGRP_RELEASABLE) |
return (cgrp->flags & bits) == bits;
}
-inline int notify_on_release(const struct cgroup *cgrp)
+static int notify_on_release(const struct cgroup *cgrp)
{
return test_bit(CGRP_NOTIFY_ON_RELEASE, &cgrp->flags);
}
/* is dentry a directory ? if so, kfree() associated cgroup */
if (S_ISDIR(inode->i_mode)) {
struct cgroup *cgrp = dentry->d_fsdata;
+ struct cgroup_subsys *ss;
BUG_ON(!(cgroup_is_removed(cgrp)));
/* It's possible for external users to be holding css
* reference counts on a cgroup; css_put() needs to
* queue the cgroup to be handled by the release
* agent */
synchronize_rcu();
+
+ mutex_lock(&cgroup_mutex);
+ /*
+ * Release the subsystem state objects.
+ */
+ for_each_subsys(cgrp->root, ss) {
+ if (cgrp->subsys[ss->subsys_id])
+ ss->destroy(ss, cgrp);
+ }
+
+ cgrp->root->number_of_cgroups--;
+ mutex_unlock(&cgroup_mutex);
+
+ /* Drop the active superblock reference that we took when we
+ * created the cgroup */
+ deactivate_super(cgrp->root->sb);
+
kfree(cgrp);
}
iput(inode);
for_each_subsys(root, ss) {
if (ss->can_attach) {
retval = ss->can_attach(ss, cgrp, tsk);
- if (retval) {
+ if (retval)
return retval;
- }
}
}
* based on its final set of cgroups
*/
newcg = find_css_set(cg, cgrp);
- if (!newcg) {
+ if (!newcg)
return -ENOMEM;
- }
task_lock(tsk);
if (tsk->flags & PF_EXITING) {
write_unlock(&css_set_lock);
for_each_subsys(root, ss) {
- if (ss->attach) {
+ if (ss->attach)
ss->attach(ss, cgrp, oldcgrp, tsk);
- }
}
set_bit(CGRP_RELEASABLE, &oldcgrp->flags);
synchronize_rcu();
goto out1;
}
buffer[nbytes] = 0; /* nul-terminate */
+ strstrip(buffer); /* strip -just- trailing whitespace */
mutex_lock(&cgroup_mutex);
+ /*
+ * This was already checked for in cgroup_file_write(), but
+ * check again now we're holding cgroup_mutex.
+ */
if (cgroup_is_removed(cgrp)) {
retval = -ENODEV;
goto out2;
clear_bit(CGRP_NOTIFY_ON_RELEASE, &cgrp->flags);
break;
case FILE_RELEASE_AGENT:
- {
- struct cgroupfs_root *root = cgrp->root;
- /* Strip trailing newline */
- if (nbytes && (buffer[nbytes-1] == '\n')) {
- buffer[nbytes-1] = 0;
- }
- if (nbytes < sizeof(root->release_agent_path)) {
- /* We never write anything other than '\0'
- * into the last char of release_agent_path,
- * so it always remains a NUL-terminated
- * string */
- strncpy(root->release_agent_path, buffer, nbytes);
- root->release_agent_path[nbytes] = 0;
- } else {
- retval = -ENOSPC;
- }
+ BUILD_BUG_ON(sizeof(cgrp->root->release_agent_path) < PATH_MAX);
+ strcpy(cgrp->root->release_agent_path, buffer);
break;
- }
default:
retval = -EINVAL;
goto out2;
struct cftype *cft = __d_cft(file->f_dentry);
struct cgroup *cgrp = __d_cgrp(file->f_dentry->d_parent);
- if (!cft)
+ if (!cft || cgroup_is_removed(cgrp))
return -ENODEV;
if (cft->write)
return cft->write(cgrp, cft, file, buf, nbytes, ppos);
struct cftype *cft = __d_cft(file->f_dentry);
struct cgroup *cgrp = __d_cgrp(file->f_dentry->d_parent);
- if (!cft)
+ if (!cft || cgroup_is_removed(cgrp))
return -ENODEV;
if (cft->read)
* matter, since it can only happen if the cgroup
* has been deleted and hence no longer needs the
* release agent to be called anyway. */
- if (css && atomic_read(&css->refcnt)) {
+ if (css && atomic_read(&css->refcnt))
return 1;
- }
}
return 0;
}
struct cgroup *cgrp = dentry->d_fsdata;
struct dentry *d;
struct cgroup *parent;
- struct cgroup_subsys *ss;
struct super_block *sb;
struct cgroupfs_root *root;
return -EBUSY;
}
- for_each_subsys(root, ss) {
- if (cgrp->subsys[ss->subsys_id])
- ss->destroy(ss, cgrp);
- }
-
spin_lock(&release_list_lock);
set_bit(CGRP_REMOVED, &cgrp->flags);
if (!list_empty(&cgrp->release_list))
cgroup_d_remove_dir(d);
dput(d);
- root->number_of_cgroups--;
set_bit(CGRP_RELEASABLE, &parent->flags);
check_for_release(parent);
mutex_unlock(&cgroup_mutex);
- /* Drop the active superblock reference that we took when we
- * created the cgroup */
- deactivate_super(sb);
return 0;
}
{
struct cgroup_subsys_state *css;
struct list_head *l;
- printk(KERN_ERR "Initializing cgroup subsys %s\n", ss->name);
+
+ printk(KERN_INFO "Initializing cgroup subsys %s\n", ss->name);
/* Create the top cgroup state for this subsystem */
ss->root = &rootnode;
BUG_ON(!ss->create);
BUG_ON(!ss->destroy);
if (ss->subsys_id != i) {
- printk(KERN_ERR "Subsys %s id == %d\n",
+ printk(KERN_ERR "cgroup: Subsys %s id == %d\n",
ss->name, ss->subsys_id);
BUG();
}
static int proc_cgroupstats_show(struct seq_file *m, void *v)
{
int i;
- struct cgroupfs_root *root;
seq_puts(m, "#subsys_name\thierarchy\tnum_cgroups\n");
mutex_lock(&cgroup_mutex);
dentry = lookup_one_len(nodename, parent->dentry, strlen(nodename));
if (IS_ERR(dentry)) {
printk(KERN_INFO
- "Couldn't allocate dentry for %s: %ld\n", nodename,
+ "cgroup: Couldn't allocate dentry for %s: %ld\n", nodename,
PTR_ERR(dentry));
ret = PTR_ERR(dentry);
goto out_release;