Merge branch 'for-3.5' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup
Pull cgroup updates from Tejun Heo:
"cgroup file type addition / removal is updated so that file types are
added and removed instead of individual files so that dynamic file
type addition / removal can be implemented by cgroup and used by
controllers. blkio controller changes which will come through block
tree are dependent on this. Other changes include res_counter cleanup
and disallowing kthread / PF_THREAD_BOUND threads to be attached to
non-root cgroups.
There's a reported bug with the file type addition / removal handling
which can lead to oops on cgroup umount. The issue is being looked
into. It shouldn't cause problems for most setups and isn't a
security concern."
Fix up trivial conflict in Documentation/feature-removal-schedule.txt
* 'for-3.5' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: (21 commits)
res_counter: Account max_usage when calling res_counter_charge_nofail()
res_counter: Merge res_counter_charge and res_counter_charge_nofail
cgroups: disallow attaching kthreadd or PF_THREAD_BOUND threads
cgroup: remove cgroup_subsys->populate()
cgroup: get rid of populate for memcg
cgroup: pass struct mem_cgroup instead of struct cgroup to socket memcg
cgroup: make css->refcnt clearing on cgroup removal optional
cgroup: use negative bias on css->refcnt to block css_tryget()
cgroup: implement cgroup_rm_cftypes()
cgroup: introduce struct cfent
cgroup: relocate __d_cgrp() and __d_cft()
cgroup: remove cgroup_add_file[s]()
cgroup: convert memcg controller to the new cftype interface
memcg: always create memsw files if CONFIG_CGROUP_MEM_RES_CTLR_SWAP
cgroup: convert all non-memcg controllers to the new cftype interface
cgroup: relocate cftype and cgroup_subsys definitions in controllers
cgroup: merge cft_release_agent cftype array into the base files array
cgroup: implement cgroup_add_cftypes() and friends
cgroup: build list of all cgroups under a given cgroupfs_root
cgroup: move cgroup_clear_directory() call out of cgroup_populate_dir()
...
diff --git a/Documentation/cgroups/resource_counter.txt b/Documentation/cgroups/resource_counter.txt
index 95b24d7..f3c4ec3 100644
--- a/Documentation/cgroups/resource_counter.txt
+++ b/Documentation/cgroups/resource_counter.txt
@@ -77,11 +77,11 @@
where the charging failed.
d. int res_counter_charge_locked
- (struct res_counter *rc, unsigned long val)
+ (struct res_counter *rc, unsigned long val, bool force)
The same as res_counter_charge(), but it must not acquire/release the
res_counter->lock internally (it must be called with res_counter->lock
- held).
+ held). The force parameter indicates whether we can bypass the limit.
e. void res_counter_uncharge[_locked]
(struct res_counter *rc, unsigned long val)
diff --git a/Documentation/feature-removal-schedule.txt b/Documentation/feature-removal-schedule.txt
index e9abede..1e69a81 100644
--- a/Documentation/feature-removal-schedule.txt
+++ b/Documentation/feature-removal-schedule.txt
@@ -556,3 +556,14 @@
There are newer controls (V4L2_CID_PAN*, V4L2_CID_TILT*) that provide
similar functionality.
Who: Sylwester Nawrocki <sylvester.nawrocki@gmail.com>
+
+----------------------------
+
+What: cgroup option updates via remount
+When: March 2013
+Why: Remount currently allows changing bound subsystems and
+ release_agent. Rebinding is hardly useful as it only works
+ when the hierarchy is empty and release_agent itself should be
+ replaced with conventional fsnotify.
+
+----------------------------
diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c
index ea84a23..126c341 100644
--- a/block/blk-cgroup.c
+++ b/block/blk-cgroup.c
@@ -28,34 +28,12 @@
struct blkio_cgroup blkio_root_cgroup = { .weight = 2*BLKIO_WEIGHT_DEFAULT };
EXPORT_SYMBOL_GPL(blkio_root_cgroup);
-static struct cgroup_subsys_state *blkiocg_create(struct cgroup *);
-static int blkiocg_can_attach(struct cgroup *, struct cgroup_taskset *);
-static void blkiocg_attach(struct cgroup *, struct cgroup_taskset *);
-static void blkiocg_destroy(struct cgroup *);
-static int blkiocg_populate(struct cgroup_subsys *, struct cgroup *);
-
/* for encoding cft->private value on file */
#define BLKIOFILE_PRIVATE(x, val) (((x) << 16) | (val))
/* What policy owns the file, proportional or throttle */
#define BLKIOFILE_POLICY(val) (((val) >> 16) & 0xffff)
#define BLKIOFILE_ATTR(val) ((val) & 0xffff)
-struct cgroup_subsys blkio_subsys = {
- .name = "blkio",
- .create = blkiocg_create,
- .can_attach = blkiocg_can_attach,
- .attach = blkiocg_attach,
- .destroy = blkiocg_destroy,
- .populate = blkiocg_populate,
-#ifdef CONFIG_BLK_CGROUP
- /* note: blkio_subsys_id is otherwise defined in blk-cgroup.h */
- .subsys_id = blkio_subsys_id,
-#endif
- .use_id = 1,
- .module = THIS_MODULE,
-};
-EXPORT_SYMBOL_GPL(blkio_subsys);
-
static inline void blkio_policy_insert_node(struct blkio_cgroup *blkcg,
struct blkio_policy_node *pn)
{
@@ -1537,14 +1515,9 @@
.read_map = blkiocg_file_read_map,
},
#endif
+ { } /* terminate */
};
-static int blkiocg_populate(struct cgroup_subsys *subsys, struct cgroup *cgroup)
-{
- return cgroup_add_files(cgroup, subsys, blkio_files,
- ARRAY_SIZE(blkio_files));
-}
-
static void blkiocg_destroy(struct cgroup *cgroup)
{
struct blkio_cgroup *blkcg = cgroup_to_blkio_cgroup(cgroup);
@@ -1658,6 +1631,22 @@
}
}
+struct cgroup_subsys blkio_subsys = {
+ .name = "blkio",
+ .create = blkiocg_create,
+ .can_attach = blkiocg_can_attach,
+ .attach = blkiocg_attach,
+ .destroy = blkiocg_destroy,
+#ifdef CONFIG_BLK_CGROUP
+ /* note: blkio_subsys_id is otherwise defined in blk-cgroup.h */
+ .subsys_id = blkio_subsys_id,
+#endif
+ .base_cftypes = blkio_files,
+ .use_id = 1,
+ .module = THIS_MODULE,
+};
+EXPORT_SYMBOL_GPL(blkio_subsys);
+
void blkio_policy_register(struct blkio_policy_type *blkiop)
{
spin_lock(&blkio_list_lock);
diff --git a/include/linux/cgroup.h b/include/linux/cgroup.h
index 5a85b34..d3f5fba 100644
--- a/include/linux/cgroup.h
+++ b/include/linux/cgroup.h
@@ -16,6 +16,7 @@
#include <linux/prio_heap.h>
#include <linux/rwsem.h>
#include <linux/idr.h>
+#include <linux/workqueue.h>
#ifdef CONFIG_CGROUPS
@@ -76,12 +77,16 @@
unsigned long flags;
/* ID for this css, if possible */
struct css_id __rcu *id;
+
+ /* Used to put @cgroup->dentry on the last css_put() */
+ struct work_struct dput_work;
};
/* bits in struct cgroup_subsys_state flags field */
enum {
CSS_ROOT, /* This CSS is the root of the subsystem */
CSS_REMOVED, /* This CSS is dead */
+ CSS_CLEAR_CSS_REFS, /* @ss->__DEPRECATED_clear_css_refs */
};
/* Caller must verify that the css is not for root cgroup */
@@ -115,16 +120,12 @@
* the css has been destroyed.
*/
+extern bool __css_tryget(struct cgroup_subsys_state *css);
static inline bool css_tryget(struct cgroup_subsys_state *css)
{
if (test_bit(CSS_ROOT, &css->flags))
return true;
- while (!atomic_inc_not_zero(&css->refcnt)) {
- if (test_bit(CSS_REMOVED, &css->flags))
- return false;
- cpu_relax();
- }
- return true;
+ return __css_tryget(css);
}
/*
@@ -132,11 +133,11 @@
* css_get() or css_tryget()
*/
-extern void __css_put(struct cgroup_subsys_state *css, int count);
+extern void __css_put(struct cgroup_subsys_state *css);
static inline void css_put(struct cgroup_subsys_state *css)
{
if (!test_bit(CSS_ROOT, &css->flags))
- __css_put(css, 1);
+ __css_put(css);
}
/* bits in struct cgroup flags field */
@@ -175,6 +176,7 @@
*/
struct list_head sibling; /* my parent's children */
struct list_head children; /* my children */
+ struct list_head files; /* my files */
struct cgroup *parent; /* my parent */
struct dentry __rcu *dentry; /* cgroup fs entry, RCU protected */
@@ -191,6 +193,9 @@
*/
struct list_head css_sets;
+ struct list_head allcg_node; /* cgroupfs_root->allcg_list */
+ struct list_head cft_q_node; /* used during cftype add/rm */
+
/*
* Linked list running through all cgroups that can
* potentially be reaped by the release agent. Protected by
@@ -275,11 +280,17 @@
* - the 'cftype' of the file is file->f_dentry->d_fsdata
*/
-#define MAX_CFTYPE_NAME 64
+/* cftype->flags */
+#define CFTYPE_ONLY_ON_ROOT (1U << 0) /* only create on root cg */
+#define CFTYPE_NOT_ON_ROOT (1U << 1) /* don't create onp root cg */
+
+#define MAX_CFTYPE_NAME 64
+
struct cftype {
/*
* By convention, the name should begin with the name of the
- * subsystem, followed by a period
+ * subsystem, followed by a period. Zero length string indicates
+ * end of cftype array.
*/
char name[MAX_CFTYPE_NAME];
int private;
@@ -295,6 +306,9 @@
*/
size_t max_write_len;
+ /* CFTYPE_* flags */
+ unsigned int flags;
+
int (*open)(struct inode *inode, struct file *file);
ssize_t (*read)(struct cgroup *cgrp, struct cftype *cft,
struct file *file,
@@ -373,6 +387,16 @@
struct eventfd_ctx *eventfd);
};
+/*
+ * cftype_sets describe cftypes belonging to a subsystem and are chained at
+ * cgroup_subsys->cftsets. Each cftset points to an array of cftypes
+ * terminated by zero length name.
+ */
+struct cftype_set {
+ struct list_head node; /* chained at subsys->cftsets */
+ const struct cftype *cfts;
+};
+
struct cgroup_scanner {
struct cgroup *cg;
int (*test_task)(struct task_struct *p, struct cgroup_scanner *scan);
@@ -382,21 +406,8 @@
void *data;
};
-/*
- * Add a new file to the given cgroup directory. Should only be
- * called by subsystems from within a populate() method
- */
-int cgroup_add_file(struct cgroup *cgrp, struct cgroup_subsys *subsys,
- const struct cftype *cft);
-
-/*
- * Add a set of new files to the given cgroup directory. Should
- * only be called by subsystems from within a populate() method
- */
-int cgroup_add_files(struct cgroup *cgrp,
- struct cgroup_subsys *subsys,
- const struct cftype cft[],
- int count);
+int cgroup_add_cftypes(struct cgroup_subsys *ss, const struct cftype *cfts);
+int cgroup_rm_cftypes(struct cgroup_subsys *ss, const struct cftype *cfts);
int cgroup_is_removed(const struct cgroup *cgrp);
@@ -461,7 +472,6 @@
void (*fork)(struct task_struct *task);
void (*exit)(struct cgroup *cgrp, struct cgroup *old_cgrp,
struct task_struct *task);
- int (*populate)(struct cgroup_subsys *ss, struct cgroup *cgrp);
void (*post_clone)(struct cgroup *cgrp);
void (*bind)(struct cgroup *root);
@@ -474,6 +484,18 @@
* (not available in early_init time.)
*/
bool use_id;
+
+ /*
+ * If %true, cgroup removal will try to clear css refs by retrying
+ * ss->pre_destroy() until there's no css ref left. This behavior
+ * is strictly for backward compatibility and will be removed as
+ * soon as the current user (memcg) is updated.
+ *
+ * If %false, ss->pre_destroy() can't fail and cgroup removal won't
+ * wait for css refs to drop to zero before proceeding.
+ */
+ bool __DEPRECATED_clear_css_refs;
+
#define MAX_CGROUP_TYPE_NAMELEN 32
const char *name;
@@ -500,6 +522,13 @@
struct idr idr;
spinlock_t id_lock;
+ /* list of cftype_sets */
+ struct list_head cftsets;
+
+ /* base cftypes, automatically [de]registered with subsys itself */
+ struct cftype *base_cftypes;
+ struct cftype_set base_cftset;
+
/* should be defined only by modular subsystems */
struct module *module;
};
diff --git a/include/linux/res_counter.h b/include/linux/res_counter.h
index da81af0..fb20189 100644
--- a/include/linux/res_counter.h
+++ b/include/linux/res_counter.h
@@ -116,7 +116,7 @@
*/
int __must_check res_counter_charge_locked(struct res_counter *counter,
- unsigned long val);
+ unsigned long val, bool force);
int __must_check res_counter_charge(struct res_counter *counter,
unsigned long val, struct res_counter **limit_fail_at);
int __must_check res_counter_charge_nofail(struct res_counter *counter,
diff --git a/include/net/sock.h b/include/net/sock.h
index da93155..d89f058 100644
--- a/include/net/sock.h
+++ b/include/net/sock.h
@@ -70,16 +70,16 @@
struct cgroup;
struct cgroup_subsys;
#ifdef CONFIG_NET
-int mem_cgroup_sockets_init(struct cgroup *cgrp, struct cgroup_subsys *ss);
-void mem_cgroup_sockets_destroy(struct cgroup *cgrp);
+int mem_cgroup_sockets_init(struct mem_cgroup *memcg, struct cgroup_subsys *ss);
+void mem_cgroup_sockets_destroy(struct mem_cgroup *memcg);
#else
static inline
-int mem_cgroup_sockets_init(struct cgroup *cgrp, struct cgroup_subsys *ss)
+int mem_cgroup_sockets_init(struct mem_cgroup *memcg, struct cgroup_subsys *ss)
{
return 0;
}
static inline
-void mem_cgroup_sockets_destroy(struct cgroup *cgrp)
+void mem_cgroup_sockets_destroy(struct mem_cgroup *memcg)
{
}
#endif
@@ -914,9 +914,9 @@
* This function has to setup any files the protocol want to
* appear in the kmem cgroup filesystem.
*/
- int (*init_cgroup)(struct cgroup *cgrp,
+ int (*init_cgroup)(struct mem_cgroup *memcg,
struct cgroup_subsys *ss);
- void (*destroy_cgroup)(struct cgroup *cgrp);
+ void (*destroy_cgroup)(struct mem_cgroup *memcg);
struct cg_proto *(*proto_cgroup)(struct mem_cgroup *memcg);
#endif
};
diff --git a/include/net/tcp_memcontrol.h b/include/net/tcp_memcontrol.h
index 48410ff..7df18bc 100644
--- a/include/net/tcp_memcontrol.h
+++ b/include/net/tcp_memcontrol.h
@@ -12,8 +12,8 @@
};
struct cg_proto *tcp_proto_cgroup(struct mem_cgroup *memcg);
-int tcp_init_cgroup(struct cgroup *cgrp, struct cgroup_subsys *ss);
-void tcp_destroy_cgroup(struct cgroup *cgrp);
+int tcp_init_cgroup(struct mem_cgroup *memcg, struct cgroup_subsys *ss);
+void tcp_destroy_cgroup(struct mem_cgroup *memcg);
unsigned long long tcp_max_memory(const struct mem_cgroup *memcg);
void tcp_prot_mem(struct mem_cgroup *memcg, long val, int idx);
#endif /* _TCP_MEMCG_H */
diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index ed64cca..ad8eae5 100644
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -60,9 +60,13 @@
#include <linux/eventfd.h>
#include <linux/poll.h>
#include <linux/flex_array.h> /* used in cgroup_attach_proc */
+#include <linux/kthread.h>
#include <linux/atomic.h>
+/* css deactivation bias, makes css->refcnt negative to deny new trygets */
+#define CSS_DEACT_BIAS INT_MIN
+
/*
* cgroup_mutex is the master lock. Any modification to cgroup or its
* hierarchy must be performed while holding it.
@@ -127,6 +131,9 @@
/* A list running through the active hierarchies */
struct list_head root_list;
+ /* All cgroups on this root, cgroup_mutex protected */
+ struct list_head allcg_list;
+
/* Hierarchy-specific flags */
unsigned long flags;
@@ -145,6 +152,15 @@
static struct cgroupfs_root rootnode;
/*
+ * cgroupfs file entry, pointed to from leaf dentry->d_fsdata.
+ */
+struct cfent {
+ struct list_head node;
+ struct dentry *dentry;
+ struct cftype *type;
+};
+
+/*
* CSS ID -- ID per subsys's Cgroup Subsys State(CSS). used only when
* cgroup_subsys->use_id != 0.
*/
@@ -239,6 +255,14 @@
EXPORT_SYMBOL_GPL(cgroup_lock_is_held);
+/* the current nr of refs, always >= 0 whether @css is deactivated or not */
+static int css_refcnt(struct cgroup_subsys_state *css)
+{
+ int v = atomic_read(&css->refcnt);
+
+ return v >= 0 ? v : v - CSS_DEACT_BIAS;
+}
+
/* convenient tests for these bits */
inline int cgroup_is_removed(const struct cgroup *cgrp)
{
@@ -279,6 +303,21 @@
#define for_each_active_root(_root) \
list_for_each_entry(_root, &roots, root_list)
+static inline struct cgroup *__d_cgrp(struct dentry *dentry)
+{
+ return dentry->d_fsdata;
+}
+
+static inline struct cfent *__d_cfe(struct dentry *dentry)
+{
+ return dentry->d_fsdata;
+}
+
+static inline struct cftype *__d_cft(struct dentry *dentry)
+{
+ return __d_cfe(dentry)->type;
+}
+
/* the list of cgroups eligible for automatic release. Protected by
* release_list_lock */
static LIST_HEAD(release_list);
@@ -816,12 +855,17 @@
struct cgroup_subsys *ss;
int ret = 0;
- for_each_subsys(cgrp->root, ss)
- if (ss->pre_destroy) {
- ret = ss->pre_destroy(cgrp);
- if (ret)
- break;
+ for_each_subsys(cgrp->root, ss) {
+ if (!ss->pre_destroy)
+ continue;
+
+ ret = ss->pre_destroy(cgrp);
+ if (ret) {
+ /* ->pre_destroy() failure is being deprecated */
+ WARN_ON_ONCE(!ss->__DEPRECATED_clear_css_refs);
+ break;
}
+ }
return ret;
}
@@ -864,6 +908,14 @@
BUG_ON(!list_empty(&cgrp->pidlists));
kfree_rcu(cgrp, rcu_head);
+ } else {
+ struct cfent *cfe = __d_cfe(dentry);
+ struct cgroup *cgrp = dentry->d_parent->d_fsdata;
+
+ WARN_ONCE(!list_empty(&cfe->node) &&
+ cgrp != &cgrp->root->top_cgroup,
+ "cfe still linked for %s\n", cfe->type->name);
+ kfree(cfe);
}
iput(inode);
}
@@ -882,34 +934,36 @@
dput(parent);
}
-static void cgroup_clear_directory(struct dentry *dentry)
+static int cgroup_rm_file(struct cgroup *cgrp, const struct cftype *cft)
{
- struct list_head *node;
+ struct cfent *cfe;
- BUG_ON(!mutex_is_locked(&dentry->d_inode->i_mutex));
- spin_lock(&dentry->d_lock);
- node = dentry->d_subdirs.next;
- while (node != &dentry->d_subdirs) {
- struct dentry *d = list_entry(node, struct dentry, d_u.d_child);
+ lockdep_assert_held(&cgrp->dentry->d_inode->i_mutex);
+ lockdep_assert_held(&cgroup_mutex);
- spin_lock_nested(&d->d_lock, DENTRY_D_LOCK_NESTED);
- list_del_init(node);
- if (d->d_inode) {
- /* This should never be called on a cgroup
- * directory with child cgroups */
- BUG_ON(d->d_inode->i_mode & S_IFDIR);
- dget_dlock(d);
- spin_unlock(&d->d_lock);
- spin_unlock(&dentry->d_lock);
- d_delete(d);
- simple_unlink(dentry->d_inode, d);
- dput(d);
- spin_lock(&dentry->d_lock);
- } else
- spin_unlock(&d->d_lock);
- node = dentry->d_subdirs.next;
+ list_for_each_entry(cfe, &cgrp->files, node) {
+ struct dentry *d = cfe->dentry;
+
+ if (cft && cfe->type != cft)
+ continue;
+
+ dget(d);
+ d_delete(d);
+ simple_unlink(d->d_inode, d);
+ list_del_init(&cfe->node);
+ dput(d);
+
+ return 0;
}
- spin_unlock(&dentry->d_lock);
+ return -ENOENT;
+}
+
+static void cgroup_clear_directory(struct dentry *dir)
+{
+ struct cgroup *cgrp = __d_cgrp(dir);
+
+ while (!list_empty(&cgrp->files))
+ cgroup_rm_file(cgrp, NULL);
}
/*
@@ -1294,6 +1348,11 @@
if (ret)
goto out_unlock;
+ /* See feature-removal-schedule.txt */
+ if (opts.subsys_bits != root->actual_subsys_bits || opts.release_agent)
+ pr_warning("cgroup: option changes via remount are deprecated (pid=%d comm=%s)\n",
+ task_tgid_nr(current), current->comm);
+
/* Don't allow flags or name to change at remount */
if (opts.flags != root->flags ||
(opts.name && strcmp(opts.name, root->name))) {
@@ -1308,7 +1367,8 @@
goto out_unlock;
}
- /* (re)populate subsystem files */
+ /* clear out any existing files and repopulate subsystem files */
+ cgroup_clear_directory(cgrp->dentry);
cgroup_populate_dir(cgrp);
if (opts.release_agent)
@@ -1333,6 +1393,7 @@
{
INIT_LIST_HEAD(&cgrp->sibling);
INIT_LIST_HEAD(&cgrp->children);
+ INIT_LIST_HEAD(&cgrp->files);
INIT_LIST_HEAD(&cgrp->css_sets);
INIT_LIST_HEAD(&cgrp->release_list);
INIT_LIST_HEAD(&cgrp->pidlists);
@@ -1344,11 +1405,14 @@
static void init_cgroup_root(struct cgroupfs_root *root)
{
struct cgroup *cgrp = &root->top_cgroup;
+
INIT_LIST_HEAD(&root->subsys_list);
INIT_LIST_HEAD(&root->root_list);
+ INIT_LIST_HEAD(&root->allcg_list);
root->number_of_cgroups = 1;
cgrp->root = root;
cgrp->top_cgroup = cgrp;
+ list_add_tail(&cgrp->allcg_node, &root->allcg_list);
init_cgroup_housekeeping(cgrp);
}
@@ -1692,16 +1756,6 @@
static struct kobject *cgroup_kobj;
-static inline struct cgroup *__d_cgrp(struct dentry *dentry)
-{
- return dentry->d_fsdata;
-}
-
-static inline struct cftype *__d_cft(struct dentry *dentry)
-{
- return dentry->d_fsdata;
-}
-
/**
* cgroup_path - generate the path of a cgroup
* @cgrp: the cgroup in question
@@ -2172,6 +2226,18 @@
if (threadgroup)
tsk = tsk->group_leader;
+
+ /*
+ * Workqueue threads may acquire PF_THREAD_BOUND and become
+ * trapped in a cpuset, or RT worker may be born in a cgroup
+ * with no rt_runtime allocated. Just say no.
+ */
+ if (tsk == kthreadd_task || (tsk->flags & PF_THREAD_BOUND)) {
+ ret = -EINVAL;
+ rcu_read_unlock();
+ goto out_unlock_cgroup;
+ }
+
get_task_struct(tsk);
rcu_read_unlock();
@@ -2603,50 +2669,191 @@
return mode;
}
-int cgroup_add_file(struct cgroup *cgrp,
- struct cgroup_subsys *subsys,
- const struct cftype *cft)
+static int cgroup_add_file(struct cgroup *cgrp, struct cgroup_subsys *subsys,
+ const struct cftype *cft)
{
struct dentry *dir = cgrp->dentry;
+ struct cgroup *parent = __d_cgrp(dir);
struct dentry *dentry;
+ struct cfent *cfe;
int error;
umode_t mode;
-
char name[MAX_CGROUP_TYPE_NAMELEN + MAX_CFTYPE_NAME + 2] = { 0 };
+
+ /* does @cft->flags tell us to skip creation on @cgrp? */
+ if ((cft->flags & CFTYPE_NOT_ON_ROOT) && !cgrp->parent)
+ return 0;
+ if ((cft->flags & CFTYPE_ONLY_ON_ROOT) && cgrp->parent)
+ return 0;
+
if (subsys && !test_bit(ROOT_NOPREFIX, &cgrp->root->flags)) {
strcpy(name, subsys->name);
strcat(name, ".");
}
strcat(name, cft->name);
+
BUG_ON(!mutex_is_locked(&dir->d_inode->i_mutex));
+
+ cfe = kzalloc(sizeof(*cfe), GFP_KERNEL);
+ if (!cfe)
+ return -ENOMEM;
+
dentry = lookup_one_len(name, dir, strlen(name));
- if (!IS_ERR(dentry)) {
- mode = cgroup_file_mode(cft);
- error = cgroup_create_file(dentry, mode | S_IFREG,
- cgrp->root->sb);
- if (!error)
- dentry->d_fsdata = (void *)cft;
- dput(dentry);
- } else
+ if (IS_ERR(dentry)) {
error = PTR_ERR(dentry);
+ goto out;
+ }
+
+ mode = cgroup_file_mode(cft);
+ error = cgroup_create_file(dentry, mode | S_IFREG, cgrp->root->sb);
+ if (!error) {
+ cfe->type = (void *)cft;
+ cfe->dentry = dentry;
+ dentry->d_fsdata = cfe;
+ list_add_tail(&cfe->node, &parent->files);
+ cfe = NULL;
+ }
+ dput(dentry);
+out:
+ kfree(cfe);
return error;
}
-EXPORT_SYMBOL_GPL(cgroup_add_file);
-int cgroup_add_files(struct cgroup *cgrp,
- struct cgroup_subsys *subsys,
- const struct cftype cft[],
- int count)
+static int cgroup_addrm_files(struct cgroup *cgrp, struct cgroup_subsys *subsys,
+ const struct cftype cfts[], bool is_add)
{
- int i, err;
- for (i = 0; i < count; i++) {
- err = cgroup_add_file(cgrp, subsys, &cft[i]);
- if (err)
- return err;
+ const struct cftype *cft;
+ int err, ret = 0;
+
+ for (cft = cfts; cft->name[0] != '\0'; cft++) {
+ if (is_add)
+ err = cgroup_add_file(cgrp, subsys, cft);
+ else
+ err = cgroup_rm_file(cgrp, cft);
+ if (err) {
+ pr_warning("cgroup_addrm_files: failed to %s %s, err=%d\n",
+ is_add ? "add" : "remove", cft->name, err);
+ ret = err;
+ }
}
+ return ret;
+}
+
+static DEFINE_MUTEX(cgroup_cft_mutex);
+
+static void cgroup_cfts_prepare(void)
+ __acquires(&cgroup_cft_mutex) __acquires(&cgroup_mutex)
+{
+ /*
+ * Thanks to the entanglement with vfs inode locking, we can't walk
+ * the existing cgroups under cgroup_mutex and create files.
+ * Instead, we increment reference on all cgroups and build list of
+ * them using @cgrp->cft_q_node. Grab cgroup_cft_mutex to ensure
+ * exclusive access to the field.
+ */
+ mutex_lock(&cgroup_cft_mutex);
+ mutex_lock(&cgroup_mutex);
+}
+
+static void cgroup_cfts_commit(struct cgroup_subsys *ss,
+ const struct cftype *cfts, bool is_add)
+ __releases(&cgroup_mutex) __releases(&cgroup_cft_mutex)
+{
+ LIST_HEAD(pending);
+ struct cgroup *cgrp, *n;
+
+ /* %NULL @cfts indicates abort and don't bother if @ss isn't attached */
+ if (cfts && ss->root != &rootnode) {
+ list_for_each_entry(cgrp, &ss->root->allcg_list, allcg_node) {
+ dget(cgrp->dentry);
+ list_add_tail(&cgrp->cft_q_node, &pending);
+ }
+ }
+
+ mutex_unlock(&cgroup_mutex);
+
+ /*
+ * All new cgroups will see @cfts update on @ss->cftsets. Add/rm
+ * files for all cgroups which were created before.
+ */
+ list_for_each_entry_safe(cgrp, n, &pending, cft_q_node) {
+ struct inode *inode = cgrp->dentry->d_inode;
+
+ mutex_lock(&inode->i_mutex);
+ mutex_lock(&cgroup_mutex);
+ if (!cgroup_is_removed(cgrp))
+ cgroup_addrm_files(cgrp, ss, cfts, is_add);
+ mutex_unlock(&cgroup_mutex);
+ mutex_unlock(&inode->i_mutex);
+
+ list_del_init(&cgrp->cft_q_node);
+ dput(cgrp->dentry);
+ }
+
+ mutex_unlock(&cgroup_cft_mutex);
+}
+
+/**
+ * cgroup_add_cftypes - add an array of cftypes to a subsystem
+ * @ss: target cgroup subsystem
+ * @cfts: zero-length name terminated array of cftypes
+ *
+ * Register @cfts to @ss. Files described by @cfts are created for all
+ * existing cgroups to which @ss is attached and all future cgroups will
+ * have them too. This function can be called anytime whether @ss is
+ * attached or not.
+ *
+ * Returns 0 on successful registration, -errno on failure. Note that this
+ * function currently returns 0 as long as @cfts registration is successful
+ * even if some file creation attempts on existing cgroups fail.
+ */
+int cgroup_add_cftypes(struct cgroup_subsys *ss, const struct cftype *cfts)
+{
+ struct cftype_set *set;
+
+ set = kzalloc(sizeof(*set), GFP_KERNEL);
+ if (!set)
+ return -ENOMEM;
+
+ cgroup_cfts_prepare();
+ set->cfts = cfts;
+ list_add_tail(&set->node, &ss->cftsets);
+ cgroup_cfts_commit(ss, cfts, true);
+
return 0;
}
-EXPORT_SYMBOL_GPL(cgroup_add_files);
+EXPORT_SYMBOL_GPL(cgroup_add_cftypes);
+
+/**
+ * cgroup_rm_cftypes - remove an array of cftypes from a subsystem
+ * @ss: target cgroup subsystem
+ * @cfts: zero-length name terminated array of cftypes
+ *
+ * Unregister @cfts from @ss. Files described by @cfts are removed from
+ * all existing cgroups to which @ss is attached and all future cgroups
+ * won't have them either. This function can be called anytime whether @ss
+ * is attached or not.
+ *
+ * Returns 0 on successful unregistration, -ENOENT if @cfts is not
+ * registered with @ss.
+ */
+int cgroup_rm_cftypes(struct cgroup_subsys *ss, const struct cftype *cfts)
+{
+ struct cftype_set *set;
+
+ cgroup_cfts_prepare();
+
+ list_for_each_entry(set, &ss->cftsets, node) {
+ if (set->cfts == cfts) {
+ list_del_init(&set->node);
+ cgroup_cfts_commit(ss, cfts, false);
+ return 0;
+ }
+ }
+
+ cgroup_cfts_commit(ss, NULL, false);
+ return -ENOENT;
+}
/**
* cgroup_task_count - count the number of tasks in a cgroup.
@@ -3625,13 +3832,14 @@
.read_u64 = cgroup_clone_children_read,
.write_u64 = cgroup_clone_children_write,
},
-};
-
-static struct cftype cft_release_agent = {
- .name = "release_agent",
- .read_seq_string = cgroup_release_agent_show,
- .write_string = cgroup_release_agent_write,
- .max_write_len = PATH_MAX,
+ {
+ .name = "release_agent",
+ .flags = CFTYPE_ONLY_ON_ROOT,
+ .read_seq_string = cgroup_release_agent_show,
+ .write_string = cgroup_release_agent_write,
+ .max_write_len = PATH_MAX,
+ },
+ { } /* terminate */
};
static int cgroup_populate_dir(struct cgroup *cgrp)
@@ -3639,22 +3847,18 @@
int err;
struct cgroup_subsys *ss;
- /* First clear out any existing files */
- cgroup_clear_directory(cgrp->dentry);
-
- err = cgroup_add_files(cgrp, NULL, files, ARRAY_SIZE(files));
+ err = cgroup_addrm_files(cgrp, NULL, files, true);
if (err < 0)
return err;
- if (cgrp == cgrp->top_cgroup) {
- if ((err = cgroup_add_file(cgrp, NULL, &cft_release_agent)) < 0)
- return err;
+ /* process cftsets of each subsystem */
+ for_each_subsys(cgrp->root, ss) {
+ struct cftype_set *set;
+
+ list_for_each_entry(set, &ss->cftsets, node)
+ cgroup_addrm_files(cgrp, ss, set->cfts, true);
}
- for_each_subsys(cgrp->root, ss) {
- if (ss->populate && (err = ss->populate(ss, cgrp)) < 0)
- return err;
- }
/* This cgroup is ready now */
for_each_subsys(cgrp->root, ss) {
struct cgroup_subsys_state *css = cgrp->subsys[ss->subsys_id];
@@ -3670,6 +3874,14 @@
return 0;
}
+static void css_dput_fn(struct work_struct *work)
+{
+ struct cgroup_subsys_state *css =
+ container_of(work, struct cgroup_subsys_state, dput_work);
+
+ dput(css->cgroup->dentry);
+}
+
static void init_cgroup_css(struct cgroup_subsys_state *css,
struct cgroup_subsys *ss,
struct cgroup *cgrp)
@@ -3682,6 +3894,16 @@
set_bit(CSS_ROOT, &css->flags);
BUG_ON(cgrp->subsys[ss->subsys_id]);
cgrp->subsys[ss->subsys_id] = css;
+
+ /*
+ * If !clear_css_refs, css holds an extra ref to @cgrp->dentry
+ * which is put on the last css_put(). dput() requires process
+ * context, which css_put() may be called without. @css->dput_work
+ * will be used to invoke dput() asynchronously from css_put().
+ */
+ INIT_WORK(&css->dput_work, css_dput_fn);
+ if (ss->__DEPRECATED_clear_css_refs)
+ set_bit(CSS_CLEAR_CSS_REFS, &css->flags);
}
static void cgroup_lock_hierarchy(struct cgroupfs_root *root)
@@ -3784,9 +4006,16 @@
if (err < 0)
goto err_remove;
+ /* If !clear_css_refs, each css holds a ref to the cgroup's dentry */
+ for_each_subsys(root, ss)
+ if (!ss->__DEPRECATED_clear_css_refs)
+ dget(dentry);
+
/* The cgroup directory was pre-locked for us */
BUG_ON(!mutex_is_locked(&cgrp->dentry->d_inode->i_mutex));
+ list_add_tail(&cgrp->allcg_node, &root->allcg_list);
+
err = cgroup_populate_dir(cgrp);
/* If err < 0, we have a half-filled directory - oh well ;) */
@@ -3826,18 +4055,19 @@
return cgroup_create(c_parent, dentry, mode | S_IFDIR);
}
+/*
+ * Check the reference count on each subsystem. Since we already
+ * established that there are no tasks in the cgroup, if the css refcount
+ * is also 1, then there should be no outstanding references, so the
+ * subsystem is safe to destroy. We scan across all subsystems rather than
+ * using the per-hierarchy linked list of mounted subsystems since we can
+ * be called via check_for_release() with no synchronization other than
+ * RCU, and the subsystem linked list isn't RCU-safe.
+ */
static int cgroup_has_css_refs(struct cgroup *cgrp)
{
- /* Check the reference count on each subsystem. Since we
- * already established that there are no tasks in the
- * cgroup, if the css refcount is also 1, then there should
- * be no outstanding references, so the subsystem is safe to
- * destroy. We scan across all subsystems rather than using
- * the per-hierarchy linked list of mounted subsystems since
- * we can be called via check_for_release() with no
- * synchronization other than RCU, and the subsystem linked
- * list isn't RCU-safe */
int i;
+
/*
* We won't need to lock the subsys array, because the subsystems
* we're concerned about aren't going anywhere since our cgroup root
@@ -3846,17 +4076,21 @@
for (i = 0; i < CGROUP_SUBSYS_COUNT; i++) {
struct cgroup_subsys *ss = subsys[i];
struct cgroup_subsys_state *css;
+
/* Skip subsystems not present or not in this hierarchy */
if (ss == NULL || ss->root != cgrp->root)
continue;
+
css = cgrp->subsys[ss->subsys_id];
- /* When called from check_for_release() it's possible
+ /*
+ * When called from check_for_release() it's possible
* that by this point the cgroup has been removed
* and the css deleted. But a false-positive doesn't
* 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) > 1))
+ * release agent to be called anyway.
+ */
+ if (css && css_refcnt(css) > 1)
return 1;
}
return 0;
@@ -3866,51 +4100,63 @@
* Atomically mark all (or else none) of the cgroup's CSS objects as
* CSS_REMOVED. Return true on success, or false if the cgroup has
* busy subsystems. Call with cgroup_mutex held
+ *
+ * Depending on whether a subsys has __DEPRECATED_clear_css_refs set or
+ * not, cgroup removal behaves differently.
+ *
+ * If clear is set, css refcnt for the subsystem should be zero before
+ * cgroup removal can be committed. This is implemented by
+ * CGRP_WAIT_ON_RMDIR and retry logic around ->pre_destroy(), which may be
+ * called multiple times until all css refcnts reach zero and is allowed to
+ * veto removal on any invocation. This behavior is deprecated and will be
+ * removed as soon as the existing user (memcg) is updated.
+ *
+ * If clear is not set, each css holds an extra reference to the cgroup's
+ * dentry and cgroup removal proceeds regardless of css refs.
+ * ->pre_destroy() will be called at least once and is not allowed to fail.
+ * On the last put of each css, whenever that may be, the extra dentry ref
+ * is put so that dentry destruction happens only after all css's are
+ * released.
*/
-
static int cgroup_clear_css_refs(struct cgroup *cgrp)
{
struct cgroup_subsys *ss;
unsigned long flags;
bool failed = false;
+
local_irq_save(flags);
+
+ /*
+ * Block new css_tryget() by deactivating refcnt. If all refcnts
+ * for subsystems w/ clear_css_refs set were 1 at the moment of
+ * deactivation, we succeeded.
+ */
for_each_subsys(cgrp->root, ss) {
struct cgroup_subsys_state *css = cgrp->subsys[ss->subsys_id];
- int refcnt;
- while (1) {
- /* We can only remove a CSS with a refcnt==1 */
- refcnt = atomic_read(&css->refcnt);
- if (refcnt > 1) {
- failed = true;
- goto done;
- }
- BUG_ON(!refcnt);
- /*
- * Drop the refcnt to 0 while we check other
- * subsystems. This will cause any racing
- * css_tryget() to spin until we set the
- * CSS_REMOVED bits or abort
- */
- if (atomic_cmpxchg(&css->refcnt, refcnt, 0) == refcnt)
- break;
- cpu_relax();
- }
+
+ WARN_ON(atomic_read(&css->refcnt) < 0);
+ atomic_add(CSS_DEACT_BIAS, &css->refcnt);
+
+ if (ss->__DEPRECATED_clear_css_refs)
+ failed |= css_refcnt(css) != 1;
}
- done:
+
+ /*
+ * If succeeded, set REMOVED and put all the base refs; otherwise,
+ * restore refcnts to positive values. Either way, all in-progress
+ * css_tryget() will be released.
+ */
for_each_subsys(cgrp->root, ss) {
struct cgroup_subsys_state *css = cgrp->subsys[ss->subsys_id];
- if (failed) {
- /*
- * Restore old refcnt if we previously managed
- * to clear it from 1 to 0
- */
- if (!atomic_read(&css->refcnt))
- atomic_set(&css->refcnt, 1);
- } else {
- /* Commit the fact that the CSS is removed */
+
+ if (!failed) {
set_bit(CSS_REMOVED, &css->flags);
+ css_put(css);
+ } else {
+ atomic_sub(CSS_DEACT_BIAS, &css->refcnt);
}
}
+
local_irq_restore(flags);
return !failed;
}
@@ -3995,6 +4241,8 @@
list_del_init(&cgrp->sibling);
cgroup_unlock_hierarchy(cgrp->root);
+ list_del_init(&cgrp->allcg_node);
+
d = dget(cgrp->dentry);
cgroup_d_remove_dir(d);
@@ -4021,12 +4269,29 @@
return 0;
}
+static void __init_or_module cgroup_init_cftsets(struct cgroup_subsys *ss)
+{
+ INIT_LIST_HEAD(&ss->cftsets);
+
+ /*
+ * base_cftset is embedded in subsys itself, no need to worry about
+ * deregistration.
+ */
+ if (ss->base_cftypes) {
+ ss->base_cftset.cfts = ss->base_cftypes;
+ list_add_tail(&ss->base_cftset.node, &ss->cftsets);
+ }
+}
+
static void __init cgroup_init_subsys(struct cgroup_subsys *ss)
{
struct cgroup_subsys_state *css;
printk(KERN_INFO "Initializing cgroup subsys %s\n", ss->name);
+ /* init base cftset */
+ cgroup_init_cftsets(ss);
+
/* Create the top cgroup state for this subsystem */
list_add(&ss->sibling, &rootnode.subsys_list);
ss->root = &rootnode;
@@ -4096,6 +4361,9 @@
return 0;
}
+ /* init base cftset */
+ cgroup_init_cftsets(ss);
+
/*
* need to register a subsys id before anything else - for example,
* init_cgroup_css needs it.
@@ -4685,21 +4953,41 @@
}
/* Caller must verify that the css is not for root cgroup */
-void __css_put(struct cgroup_subsys_state *css, int count)
+bool __css_tryget(struct cgroup_subsys_state *css)
+{
+ do {
+ int v = css_refcnt(css);
+
+ if (atomic_cmpxchg(&css->refcnt, v, v + 1) == v)
+ return true;
+ cpu_relax();
+ } while (!test_bit(CSS_REMOVED, &css->flags));
+
+ return false;
+}
+EXPORT_SYMBOL_GPL(__css_tryget);
+
+/* Caller must verify that the css is not for root cgroup */
+void __css_put(struct cgroup_subsys_state *css)
{
struct cgroup *cgrp = css->cgroup;
- int val;
+
rcu_read_lock();
- val = atomic_sub_return(count, &css->refcnt);
- if (val == 1) {
+ atomic_dec(&css->refcnt);
+ switch (css_refcnt(css)) {
+ case 1:
if (notify_on_release(cgrp)) {
set_bit(CGRP_RELEASABLE, &cgrp->flags);
check_for_release(cgrp);
}
cgroup_wakeup_rmdir_waiter(cgrp);
+ break;
+ case 0:
+ if (!test_bit(CSS_CLEAR_CSS_REFS, &css->flags))
+ schedule_work(&css->dput_work);
+ break;
}
rcu_read_unlock();
- WARN_ON_ONCE(val < 1);
}
EXPORT_SYMBOL_GPL(__css_put);
@@ -4818,7 +5106,7 @@
* on this or this is under rcu_read_lock(). Once css->id is allocated,
* it's unchanged until freed.
*/
- cssid = rcu_dereference_check(css->id, atomic_read(&css->refcnt));
+ cssid = rcu_dereference_check(css->id, css_refcnt(css));
if (cssid)
return cssid->id;
@@ -4830,7 +5118,7 @@
{
struct css_id *cssid;
- cssid = rcu_dereference_check(css->id, atomic_read(&css->refcnt));
+ cssid = rcu_dereference_check(css->id, css_refcnt(css));
if (cssid)
return cssid->depth;
@@ -5211,19 +5499,15 @@
.name = "releasable",
.read_u64 = releasable_read,
},
-};
-static int debug_populate(struct cgroup_subsys *ss, struct cgroup *cont)
-{
- return cgroup_add_files(cont, ss, debug_files,
- ARRAY_SIZE(debug_files));
-}
+ { } /* terminate */
+};
struct cgroup_subsys debug_subsys = {
.name = "debug",
.create = debug_create,
.destroy = debug_destroy,
- .populate = debug_populate,
.subsys_id = debug_subsys_id,
+ .base_cftypes = debug_files,
};
#endif /* CONFIG_CGROUP_DEBUG */
diff --git a/kernel/cgroup_freezer.c b/kernel/cgroup_freezer.c
index f86e939..3649fc6 100644
--- a/kernel/cgroup_freezer.c
+++ b/kernel/cgroup_freezer.c
@@ -358,24 +358,19 @@
static struct cftype files[] = {
{
.name = "state",
+ .flags = CFTYPE_NOT_ON_ROOT,
.read_seq_string = freezer_read,
.write_string = freezer_write,
},
+ { } /* terminate */
};
-static int freezer_populate(struct cgroup_subsys *ss, struct cgroup *cgroup)
-{
- if (!cgroup->parent)
- return 0;
- return cgroup_add_files(cgroup, ss, files, ARRAY_SIZE(files));
-}
-
struct cgroup_subsys freezer_subsys = {
.name = "freezer",
.create = freezer_create,
.destroy = freezer_destroy,
- .populate = freezer_populate,
.subsys_id = freezer_subsys_id,
.can_attach = freezer_can_attach,
.fork = freezer_fork,
+ .base_cftypes = files,
};
diff --git a/kernel/cpuset.c b/kernel/cpuset.c
index 14f7070..8c8bd65 100644
--- a/kernel/cpuset.c
+++ b/kernel/cpuset.c
@@ -1765,29 +1765,18 @@
.write_u64 = cpuset_write_u64,
.private = FILE_SPREAD_SLAB,
},
+
+ {
+ .name = "memory_pressure_enabled",
+ .flags = CFTYPE_ONLY_ON_ROOT,
+ .read_u64 = cpuset_read_u64,
+ .write_u64 = cpuset_write_u64,
+ .private = FILE_MEMORY_PRESSURE_ENABLED,
+ },
+
+ { } /* terminate */
};
-static struct cftype cft_memory_pressure_enabled = {
- .name = "memory_pressure_enabled",
- .read_u64 = cpuset_read_u64,
- .write_u64 = cpuset_write_u64,
- .private = FILE_MEMORY_PRESSURE_ENABLED,
-};
-
-static int cpuset_populate(struct cgroup_subsys *ss, struct cgroup *cont)
-{
- int err;
-
- err = cgroup_add_files(cont, ss, files, ARRAY_SIZE(files));
- if (err)
- return err;
- /* memory_pressure_enabled is in root cpuset only */
- if (!cont->parent)
- err = cgroup_add_file(cont, ss,
- &cft_memory_pressure_enabled);
- return err;
-}
-
/*
* post_clone() is called during cgroup_create() when the
* clone_children mount argument was specified. The cgroup
@@ -1887,9 +1876,9 @@
.destroy = cpuset_destroy,
.can_attach = cpuset_can_attach,
.attach = cpuset_attach,
- .populate = cpuset_populate,
.post_clone = cpuset_post_clone,
.subsys_id = cpuset_subsys_id,
+ .base_cftypes = files,
.early_init = 1,
};
diff --git a/kernel/res_counter.c b/kernel/res_counter.c
index d508363..bebe2b1 100644
--- a/kernel/res_counter.c
+++ b/kernel/res_counter.c
@@ -22,75 +22,70 @@
counter->parent = parent;
}
-int res_counter_charge_locked(struct res_counter *counter, unsigned long val)
+int res_counter_charge_locked(struct res_counter *counter, unsigned long val,
+ bool force)
{
+ int ret = 0;
+
if (counter->usage + val > counter->limit) {
counter->failcnt++;
- return -ENOMEM;
+ ret = -ENOMEM;
+ if (!force)
+ return ret;
}
counter->usage += val;
if (counter->usage > counter->max_usage)
counter->max_usage = counter->usage;
- return 0;
-}
-
-int res_counter_charge(struct res_counter *counter, unsigned long val,
- struct res_counter **limit_fail_at)
-{
- int ret;
- unsigned long flags;
- struct res_counter *c, *u;
-
- *limit_fail_at = NULL;
- local_irq_save(flags);
- for (c = counter; c != NULL; c = c->parent) {
- spin_lock(&c->lock);
- ret = res_counter_charge_locked(c, val);
- spin_unlock(&c->lock);
- if (ret < 0) {
- *limit_fail_at = c;
- goto undo;
- }
- }
- ret = 0;
- goto done;
-undo:
- for (u = counter; u != c; u = u->parent) {
- spin_lock(&u->lock);
- res_counter_uncharge_locked(u, val);
- spin_unlock(&u->lock);
- }
-done:
- local_irq_restore(flags);
return ret;
}
-int res_counter_charge_nofail(struct res_counter *counter, unsigned long val,
- struct res_counter **limit_fail_at)
+static int __res_counter_charge(struct res_counter *counter, unsigned long val,
+ struct res_counter **limit_fail_at, bool force)
{
int ret, r;
unsigned long flags;
- struct res_counter *c;
+ struct res_counter *c, *u;
r = ret = 0;
*limit_fail_at = NULL;
local_irq_save(flags);
for (c = counter; c != NULL; c = c->parent) {
spin_lock(&c->lock);
- r = res_counter_charge_locked(c, val);
- if (r)
- c->usage += val;
+ r = res_counter_charge_locked(c, val, force);
spin_unlock(&c->lock);
- if (r < 0 && ret == 0) {
- *limit_fail_at = c;
+ if (r < 0 && !ret) {
ret = r;
+ *limit_fail_at = c;
+ if (!force)
+ break;
+ }
+ }
+
+ if (ret < 0 && !force) {
+ for (u = counter; u != c; u = u->parent) {
+ spin_lock(&u->lock);
+ res_counter_uncharge_locked(u, val);
+ spin_unlock(&u->lock);
}
}
local_irq_restore(flags);
return ret;
}
+
+int res_counter_charge(struct res_counter *counter, unsigned long val,
+ struct res_counter **limit_fail_at)
+{
+ return __res_counter_charge(counter, val, limit_fail_at, false);
+}
+
+int res_counter_charge_nofail(struct res_counter *counter, unsigned long val,
+ struct res_counter **limit_fail_at)
+{
+ return __res_counter_charge(counter, val, limit_fail_at, true);
+}
+
void res_counter_uncharge_locked(struct res_counter *counter, unsigned long val)
{
if (WARN_ON(counter->usage < val))
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index ea8a476..03667c3 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -7985,13 +7985,9 @@
.write_u64 = cpu_rt_period_write_uint,
},
#endif
+ { } /* terminate */
};
-static int cpu_cgroup_populate(struct cgroup_subsys *ss, struct cgroup *cont)
-{
- return cgroup_add_files(cont, ss, cpu_files, ARRAY_SIZE(cpu_files));
-}
-
struct cgroup_subsys cpu_cgroup_subsys = {
.name = "cpu",
.create = cpu_cgroup_create,
@@ -7999,8 +7995,8 @@
.can_attach = cpu_cgroup_can_attach,
.attach = cpu_cgroup_attach,
.exit = cpu_cgroup_exit,
- .populate = cpu_cgroup_populate,
.subsys_id = cpu_cgroup_subsys_id,
+ .base_cftypes = cpu_files,
.early_init = 1,
};
@@ -8185,13 +8181,9 @@
.name = "stat",
.read_map = cpuacct_stats_show,
},
+ { } /* terminate */
};
-static int cpuacct_populate(struct cgroup_subsys *ss, struct cgroup *cgrp)
-{
- return cgroup_add_files(cgrp, ss, files, ARRAY_SIZE(files));
-}
-
/*
* charge this task's execution time to its accounting group.
*
@@ -8223,7 +8215,7 @@
.name = "cpuacct",
.create = cpuacct_create,
.destroy = cpuacct_destroy,
- .populate = cpuacct_populate,
.subsys_id = cpuacct_subsys_id,
+ .base_cftypes = files,
};
#endif /* CONFIG_CGROUP_CPUACCT */
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 7685d4a..f342778 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -3873,14 +3873,21 @@
return val << PAGE_SHIFT;
}
-static u64 mem_cgroup_read(struct cgroup *cont, struct cftype *cft)
+static ssize_t mem_cgroup_read(struct cgroup *cont, struct cftype *cft,
+ struct file *file, char __user *buf,
+ size_t nbytes, loff_t *ppos)
{
struct mem_cgroup *memcg = mem_cgroup_from_cont(cont);
+ char str[64];
u64 val;
- int type, name;
+ int type, name, len;
type = MEMFILE_TYPE(cft->private);
name = MEMFILE_ATTR(cft->private);
+
+ if (!do_swap_account && type == _MEMSWAP)
+ return -EOPNOTSUPP;
+
switch (type) {
case _MEM:
if (name == RES_USAGE)
@@ -3897,7 +3904,9 @@
default:
BUG();
}
- return val;
+
+ len = scnprintf(str, sizeof(str), "%llu\n", (unsigned long long)val);
+ return simple_read_from_buffer(buf, nbytes, ppos, str, len);
}
/*
* The user of this function is...
@@ -3913,6 +3922,10 @@
type = MEMFILE_TYPE(cft->private);
name = MEMFILE_ATTR(cft->private);
+
+ if (!do_swap_account && type == _MEMSWAP)
+ return -EOPNOTSUPP;
+
switch (name) {
case RES_LIMIT:
if (mem_cgroup_is_root(memcg)) { /* Can't set limit on root */
@@ -3978,12 +3991,15 @@
static int mem_cgroup_reset(struct cgroup *cont, unsigned int event)
{
- struct mem_cgroup *memcg;
+ struct mem_cgroup *memcg = mem_cgroup_from_cont(cont);
int type, name;
- memcg = mem_cgroup_from_cont(cont);
type = MEMFILE_TYPE(event);
name = MEMFILE_ATTR(event);
+
+ if (!do_swap_account && type == _MEMSWAP)
+ return -EOPNOTSUPP;
+
switch (name) {
case RES_MAX_USAGE:
if (type == _MEM)
@@ -4624,29 +4640,22 @@
#endif /* CONFIG_NUMA */
#ifdef CONFIG_CGROUP_MEM_RES_CTLR_KMEM
-static int register_kmem_files(struct cgroup *cont, struct cgroup_subsys *ss)
+static int memcg_init_kmem(struct mem_cgroup *memcg, struct cgroup_subsys *ss)
{
- /*
- * Part of this would be better living in a separate allocation
- * function, leaving us with just the cgroup tree population work.
- * We, however, depend on state such as network's proto_list that
- * is only initialized after cgroup creation. I found the less
- * cumbersome way to deal with it to defer it all to populate time
- */
- return mem_cgroup_sockets_init(cont, ss);
+ return mem_cgroup_sockets_init(memcg, ss);
};
-static void kmem_cgroup_destroy(struct cgroup *cont)
+static void kmem_cgroup_destroy(struct mem_cgroup *memcg)
{
- mem_cgroup_sockets_destroy(cont);
+ mem_cgroup_sockets_destroy(memcg);
}
#else
-static int register_kmem_files(struct cgroup *cont, struct cgroup_subsys *ss)
+static int memcg_init_kmem(struct mem_cgroup *memcg, struct cgroup_subsys *ss)
{
return 0;
}
-static void kmem_cgroup_destroy(struct cgroup *cont)
+static void kmem_cgroup_destroy(struct mem_cgroup *memcg)
{
}
#endif
@@ -4655,7 +4664,7 @@
{
.name = "usage_in_bytes",
.private = MEMFILE_PRIVATE(_MEM, RES_USAGE),
- .read_u64 = mem_cgroup_read,
+ .read = mem_cgroup_read,
.register_event = mem_cgroup_usage_register_event,
.unregister_event = mem_cgroup_usage_unregister_event,
},
@@ -4663,25 +4672,25 @@
.name = "max_usage_in_bytes",
.private = MEMFILE_PRIVATE(_MEM, RES_MAX_USAGE),
.trigger = mem_cgroup_reset,
- .read_u64 = mem_cgroup_read,
+ .read = mem_cgroup_read,
},
{
.name = "limit_in_bytes",
.private = MEMFILE_PRIVATE(_MEM, RES_LIMIT),
.write_string = mem_cgroup_write,
- .read_u64 = mem_cgroup_read,
+ .read = mem_cgroup_read,
},
{
.name = "soft_limit_in_bytes",
.private = MEMFILE_PRIVATE(_MEM, RES_SOFT_LIMIT),
.write_string = mem_cgroup_write,
- .read_u64 = mem_cgroup_read,
+ .read = mem_cgroup_read,
},
{
.name = "failcnt",
.private = MEMFILE_PRIVATE(_MEM, RES_FAILCNT),
.trigger = mem_cgroup_reset,
- .read_u64 = mem_cgroup_read,
+ .read = mem_cgroup_read,
},
{
.name = "stat",
@@ -4721,14 +4730,11 @@
.mode = S_IRUGO,
},
#endif
-};
-
#ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP
-static struct cftype memsw_cgroup_files[] = {
{
.name = "memsw.usage_in_bytes",
.private = MEMFILE_PRIVATE(_MEMSWAP, RES_USAGE),
- .read_u64 = mem_cgroup_read,
+ .read = mem_cgroup_read,
.register_event = mem_cgroup_usage_register_event,
.unregister_event = mem_cgroup_usage_unregister_event,
},
@@ -4736,35 +4742,23 @@
.name = "memsw.max_usage_in_bytes",
.private = MEMFILE_PRIVATE(_MEMSWAP, RES_MAX_USAGE),
.trigger = mem_cgroup_reset,
- .read_u64 = mem_cgroup_read,
+ .read = mem_cgroup_read,
},
{
.name = "memsw.limit_in_bytes",
.private = MEMFILE_PRIVATE(_MEMSWAP, RES_LIMIT),
.write_string = mem_cgroup_write,
- .read_u64 = mem_cgroup_read,
+ .read = mem_cgroup_read,
},
{
.name = "memsw.failcnt",
.private = MEMFILE_PRIVATE(_MEMSWAP, RES_FAILCNT),
.trigger = mem_cgroup_reset,
- .read_u64 = mem_cgroup_read,
+ .read = mem_cgroup_read,
},
-};
-
-static int register_memsw_files(struct cgroup *cont, struct cgroup_subsys *ss)
-{
- if (!do_swap_account)
- return 0;
- return cgroup_add_files(cont, ss, memsw_cgroup_files,
- ARRAY_SIZE(memsw_cgroup_files));
-};
-#else
-static int register_memsw_files(struct cgroup *cont, struct cgroup_subsys *ss)
-{
- return 0;
-}
#endif
+ { }, /* terminate */
+};
static int alloc_mem_cgroup_per_zone_info(struct mem_cgroup *memcg, int node)
{
@@ -5016,6 +5010,17 @@
memcg->move_charge_at_immigrate = 0;
mutex_init(&memcg->thresholds_lock);
spin_lock_init(&memcg->move_lock);
+
+ error = memcg_init_kmem(memcg, &mem_cgroup_subsys);
+ if (error) {
+ /*
+ * We call put now because our (and parent's) refcnts
+ * are already in place. mem_cgroup_put() will internally
+ * call __mem_cgroup_free, so return directly
+ */
+ mem_cgroup_put(memcg);
+ return ERR_PTR(error);
+ }
return &memcg->css;
free_out:
__mem_cgroup_free(memcg);
@@ -5033,28 +5038,11 @@
{
struct mem_cgroup *memcg = mem_cgroup_from_cont(cont);
- kmem_cgroup_destroy(cont);
+ kmem_cgroup_destroy(memcg);
mem_cgroup_put(memcg);
}
-static int mem_cgroup_populate(struct cgroup_subsys *ss,
- struct cgroup *cont)
-{
- int ret;
-
- ret = cgroup_add_files(cont, ss, mem_cgroup_files,
- ARRAY_SIZE(mem_cgroup_files));
-
- if (!ret)
- ret = register_memsw_files(cont, ss);
-
- if (!ret)
- ret = register_kmem_files(cont, ss);
-
- return ret;
-}
-
#ifdef CONFIG_MMU
/* Handlers for move charge at task migration. */
#define PRECHARGE_COUNT_AT_ONCE 256
@@ -5638,12 +5626,13 @@
.create = mem_cgroup_create,
.pre_destroy = mem_cgroup_pre_destroy,
.destroy = mem_cgroup_destroy,
- .populate = mem_cgroup_populate,
.can_attach = mem_cgroup_can_attach,
.cancel_attach = mem_cgroup_cancel_attach,
.attach = mem_cgroup_move_task,
+ .base_cftypes = mem_cgroup_files,
.early_init = 0,
.use_id = 1,
+ .__DEPRECATED_clear_css_refs = true,
};
#ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP
diff --git a/net/core/netprio_cgroup.c b/net/core/netprio_cgroup.c
index 09eda68..5b8aa2f 100644
--- a/net/core/netprio_cgroup.c
+++ b/net/core/netprio_cgroup.c
@@ -25,21 +25,6 @@
#include <net/sock.h>
#include <net/netprio_cgroup.h>
-static struct cgroup_subsys_state *cgrp_create(struct cgroup *cgrp);
-static void cgrp_destroy(struct cgroup *cgrp);
-static int cgrp_populate(struct cgroup_subsys *ss, struct cgroup *cgrp);
-
-struct cgroup_subsys net_prio_subsys = {
- .name = "net_prio",
- .create = cgrp_create,
- .destroy = cgrp_destroy,
- .populate = cgrp_populate,
-#ifdef CONFIG_NETPRIO_CGROUP
- .subsys_id = net_prio_subsys_id,
-#endif
- .module = THIS_MODULE
-};
-
#define PRIOIDX_SZ 128
static unsigned long prioidx_map[PRIOIDX_SZ];
@@ -259,12 +244,19 @@
.read_map = read_priomap,
.write_string = write_priomap,
},
+ { } /* terminate */
};
-static int cgrp_populate(struct cgroup_subsys *ss, struct cgroup *cgrp)
-{
- return cgroup_add_files(cgrp, ss, ss_files, ARRAY_SIZE(ss_files));
-}
+struct cgroup_subsys net_prio_subsys = {
+ .name = "net_prio",
+ .create = cgrp_create,
+ .destroy = cgrp_destroy,
+#ifdef CONFIG_NETPRIO_CGROUP
+ .subsys_id = net_prio_subsys_id,
+#endif
+ .base_cftypes = ss_files,
+ .module = THIS_MODULE
+};
static int netprio_device_event(struct notifier_block *unused,
unsigned long event, void *ptr)
diff --git a/net/core/sock.c b/net/core/sock.c
index 5efcd63..f372d9b 100644
--- a/net/core/sock.c
+++ b/net/core/sock.c
@@ -143,7 +143,7 @@
static LIST_HEAD(proto_list);
#ifdef CONFIG_CGROUP_MEM_RES_CTLR_KMEM
-int mem_cgroup_sockets_init(struct cgroup *cgrp, struct cgroup_subsys *ss)
+int mem_cgroup_sockets_init(struct mem_cgroup *memcg, struct cgroup_subsys *ss)
{
struct proto *proto;
int ret = 0;
@@ -151,7 +151,7 @@
mutex_lock(&proto_list_mutex);
list_for_each_entry(proto, &proto_list, node) {
if (proto->init_cgroup) {
- ret = proto->init_cgroup(cgrp, ss);
+ ret = proto->init_cgroup(memcg, ss);
if (ret)
goto out;
}
@@ -162,19 +162,19 @@
out:
list_for_each_entry_continue_reverse(proto, &proto_list, node)
if (proto->destroy_cgroup)
- proto->destroy_cgroup(cgrp);
+ proto->destroy_cgroup(memcg);
mutex_unlock(&proto_list_mutex);
return ret;
}
-void mem_cgroup_sockets_destroy(struct cgroup *cgrp)
+void mem_cgroup_sockets_destroy(struct mem_cgroup *memcg)
{
struct proto *proto;
mutex_lock(&proto_list_mutex);
list_for_each_entry_reverse(proto, &proto_list, node)
if (proto->destroy_cgroup)
- proto->destroy_cgroup(cgrp);
+ proto->destroy_cgroup(memcg);
mutex_unlock(&proto_list_mutex);
}
#endif
diff --git a/net/ipv4/tcp_memcontrol.c b/net/ipv4/tcp_memcontrol.c
index e795272..1517037 100644
--- a/net/ipv4/tcp_memcontrol.c
+++ b/net/ipv4/tcp_memcontrol.c
@@ -6,37 +6,6 @@
#include <linux/memcontrol.h>
#include <linux/module.h>
-static u64 tcp_cgroup_read(struct cgroup *cont, struct cftype *cft);
-static int tcp_cgroup_write(struct cgroup *cont, struct cftype *cft,
- const char *buffer);
-static int tcp_cgroup_reset(struct cgroup *cont, unsigned int event);
-
-static struct cftype tcp_files[] = {
- {
- .name = "kmem.tcp.limit_in_bytes",
- .write_string = tcp_cgroup_write,
- .read_u64 = tcp_cgroup_read,
- .private = RES_LIMIT,
- },
- {
- .name = "kmem.tcp.usage_in_bytes",
- .read_u64 = tcp_cgroup_read,
- .private = RES_USAGE,
- },
- {
- .name = "kmem.tcp.failcnt",
- .private = RES_FAILCNT,
- .trigger = tcp_cgroup_reset,
- .read_u64 = tcp_cgroup_read,
- },
- {
- .name = "kmem.tcp.max_usage_in_bytes",
- .private = RES_MAX_USAGE,
- .trigger = tcp_cgroup_reset,
- .read_u64 = tcp_cgroup_read,
- },
-};
-
static inline struct tcp_memcontrol *tcp_from_cgproto(struct cg_proto *cg_proto)
{
return container_of(cg_proto, struct tcp_memcontrol, cg_proto);
@@ -49,7 +18,7 @@
}
EXPORT_SYMBOL(memcg_tcp_enter_memory_pressure);
-int tcp_init_cgroup(struct cgroup *cgrp, struct cgroup_subsys *ss)
+int tcp_init_cgroup(struct mem_cgroup *memcg, struct cgroup_subsys *ss)
{
/*
* The root cgroup does not use res_counters, but rather,
@@ -59,13 +28,12 @@
struct res_counter *res_parent = NULL;
struct cg_proto *cg_proto, *parent_cg;
struct tcp_memcontrol *tcp;
- struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp);
struct mem_cgroup *parent = parent_mem_cgroup(memcg);
struct net *net = current->nsproxy->net_ns;
cg_proto = tcp_prot.proto_cgroup(memcg);
if (!cg_proto)
- goto create_files;
+ return 0;
tcp = tcp_from_cgproto(cg_proto);
@@ -88,15 +56,12 @@
cg_proto->sockets_allocated = &tcp->tcp_sockets_allocated;
cg_proto->memcg = memcg;
-create_files:
- return cgroup_add_files(cgrp, ss, tcp_files,
- ARRAY_SIZE(tcp_files));
+ return 0;
}
EXPORT_SYMBOL(tcp_init_cgroup);
-void tcp_destroy_cgroup(struct cgroup *cgrp)
+void tcp_destroy_cgroup(struct mem_cgroup *memcg)
{
- struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp);
struct cg_proto *cg_proto;
struct tcp_memcontrol *tcp;
u64 val;
@@ -270,3 +235,37 @@
tcp->tcp_prot_mem[idx] = val;
}
+
+static struct cftype tcp_files[] = {
+ {
+ .name = "kmem.tcp.limit_in_bytes",
+ .write_string = tcp_cgroup_write,
+ .read_u64 = tcp_cgroup_read,
+ .private = RES_LIMIT,
+ },
+ {
+ .name = "kmem.tcp.usage_in_bytes",
+ .read_u64 = tcp_cgroup_read,
+ .private = RES_USAGE,
+ },
+ {
+ .name = "kmem.tcp.failcnt",
+ .private = RES_FAILCNT,
+ .trigger = tcp_cgroup_reset,
+ .read_u64 = tcp_cgroup_read,
+ },
+ {
+ .name = "kmem.tcp.max_usage_in_bytes",
+ .private = RES_MAX_USAGE,
+ .trigger = tcp_cgroup_reset,
+ .read_u64 = tcp_cgroup_read,
+ },
+ { } /* terminate */
+};
+
+static int __init tcp_memcontrol_init(void)
+{
+ WARN_ON(cgroup_add_cftypes(&mem_cgroup_subsys, tcp_files));
+ return 0;
+}
+__initcall(tcp_memcontrol_init);
diff --git a/net/sched/cls_cgroup.c b/net/sched/cls_cgroup.c
index 1afaa28..7743ea8 100644
--- a/net/sched/cls_cgroup.c
+++ b/net/sched/cls_cgroup.c
@@ -22,22 +22,6 @@
#include <net/sock.h>
#include <net/cls_cgroup.h>
-static struct cgroup_subsys_state *cgrp_create(struct cgroup *cgrp);
-static void cgrp_destroy(struct cgroup *cgrp);
-static int cgrp_populate(struct cgroup_subsys *ss, struct cgroup *cgrp);
-
-struct cgroup_subsys net_cls_subsys = {
- .name = "net_cls",
- .create = cgrp_create,
- .destroy = cgrp_destroy,
- .populate = cgrp_populate,
-#ifdef CONFIG_NET_CLS_CGROUP
- .subsys_id = net_cls_subsys_id,
-#endif
- .module = THIS_MODULE,
-};
-
-
static inline struct cgroup_cls_state *cgrp_cls_state(struct cgroup *cgrp)
{
return container_of(cgroup_subsys_state(cgrp, net_cls_subsys_id),
@@ -86,12 +70,19 @@
.read_u64 = read_classid,
.write_u64 = write_classid,
},
+ { } /* terminate */
};
-static int cgrp_populate(struct cgroup_subsys *ss, struct cgroup *cgrp)
-{
- return cgroup_add_files(cgrp, ss, ss_files, ARRAY_SIZE(ss_files));
-}
+struct cgroup_subsys net_cls_subsys = {
+ .name = "net_cls",
+ .create = cgrp_create,
+ .destroy = cgrp_destroy,
+#ifdef CONFIG_NET_CLS_CGROUP
+ .subsys_id = net_cls_subsys_id,
+#endif
+ .base_cftypes = ss_files,
+ .module = THIS_MODULE,
+};
struct cls_cgroup_head {
u32 handle;
diff --git a/security/device_cgroup.c b/security/device_cgroup.c
index c43a332..442204c 100644
--- a/security/device_cgroup.c
+++ b/security/device_cgroup.c
@@ -447,22 +447,16 @@
.read_seq_string = devcgroup_seq_read,
.private = DEVCG_LIST,
},
+ { } /* terminate */
};
-static int devcgroup_populate(struct cgroup_subsys *ss,
- struct cgroup *cgroup)
-{
- return cgroup_add_files(cgroup, ss, dev_cgroup_files,
- ARRAY_SIZE(dev_cgroup_files));
-}
-
struct cgroup_subsys devices_subsys = {
.name = "devices",
.can_attach = devcgroup_can_attach,
.create = devcgroup_create,
.destroy = devcgroup_destroy,
- .populate = devcgroup_populate,
.subsys_id = devices_subsys_id,
+ .base_cftypes = dev_cgroup_files,
};
int __devcgroup_inode_permission(struct inode *inode, int mask)