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-rw-r--r--Documentation/cgroups/cgroups.txt14
-rw-r--r--Documentation/cgroups/unified-hierarchy.txt35
-rw-r--r--block/blk-cgroup.c13
-rw-r--r--block/blk-throttle.c6
-rw-r--r--include/linux/cgroup.h165
-rw-r--r--kernel/cgroup.c453
-rw-r--r--kernel/cgroup_freezer.c2
-rw-r--r--kernel/cpuset.c500
-rw-r--r--kernel/sched/core.c2
-rw-r--r--kernel/sched/cpuacct.c2
-rw-r--r--mm/hugetlb_cgroup.c5
-rw-r--r--mm/memcontrol.c37
-rw-r--r--net/core/netclassid_cgroup.c2
-rw-r--r--net/core/netprio_cgroup.c2
-rw-r--r--net/ipv4/tcp_memcontrol.c2
-rw-r--r--security/device_cgroup.c2
16 files changed, 806 insertions, 436 deletions
diff --git a/Documentation/cgroups/cgroups.txt b/Documentation/cgroups/cgroups.txt
index 821de56d1580..10c949b293e4 100644
--- a/Documentation/cgroups/cgroups.txt
+++ b/Documentation/cgroups/cgroups.txt
@@ -599,6 +599,20 @@ fork. If this method returns 0 (success) then this should remain valid
while the caller holds cgroup_mutex and it is ensured that either
attach() or cancel_attach() will be called in future.
+void css_reset(struct cgroup_subsys_state *css)
+(cgroup_mutex held by caller)
+
+An optional operation which should restore @css's configuration to the
+initial state. This is currently only used on the unified hierarchy
+when a subsystem is disabled on a cgroup through
+"cgroup.subtree_control" but should remain enabled because other
+subsystems depend on it. cgroup core makes such a css invisible by
+removing the associated interface files and invokes this callback so
+that the hidden subsystem can return to the initial neutral state.
+This prevents unexpected resource control from a hidden css and
+ensures that the configuration is in the initial state when it is made
+visible again later.
+
void cancel_attach(struct cgroup *cgrp, struct cgroup_taskset *tset)
(cgroup_mutex held by caller)
diff --git a/Documentation/cgroups/unified-hierarchy.txt b/Documentation/cgroups/unified-hierarchy.txt
index 324b182e6000..4f4563277864 100644
--- a/Documentation/cgroups/unified-hierarchy.txt
+++ b/Documentation/cgroups/unified-hierarchy.txt
@@ -94,12 +94,35 @@ change soon.
mount -t cgroup -o __DEVEL__sane_behavior cgroup $MOUNT_POINT
-All controllers which are not bound to other hierarchies are
-automatically bound to unified hierarchy and show up at the root of
-it. Controllers which are enabled only in the root of unified
-hierarchy can be bound to other hierarchies at any time. This allows
-mixing unified hierarchy with the traditional multiple hierarchies in
-a fully backward compatible way.
+All controllers which support the unified hierarchy and are not bound
+to other hierarchies are automatically bound to unified hierarchy and
+show up at the root of it. Controllers which are enabled only in the
+root of unified hierarchy can be bound to other hierarchies. This
+allows mixing unified hierarchy with the traditional multiple
+hierarchies in a fully backward compatible way.
+
+For development purposes, the following boot parameter makes all
+controllers to appear on the unified hierarchy whether supported or
+not.
+
+ cgroup__DEVEL__legacy_files_on_dfl
+
+A controller can be moved across hierarchies only after the controller
+is no longer referenced in its current hierarchy. Because per-cgroup
+controller states are destroyed asynchronously and controllers may
+have lingering references, a controller may not show up immediately on
+the unified hierarchy after the final umount of the previous
+hierarchy. Similarly, a controller should be fully disabled to be
+moved out of the unified hierarchy and it may take some time for the
+disabled controller to become available for other hierarchies;
+furthermore, due to dependencies among controllers, other controllers
+may need to be disabled too.
+
+While useful for development and manual configurations, dynamically
+moving controllers between the unified and other hierarchies is
+strongly discouraged for production use. It is recommended to decide
+the hierarchies and controller associations before starting using the
+controllers.
2-2. cgroup.subtree_control
diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c
index 28d227c5ca77..e17da947f6bd 100644
--- a/block/blk-cgroup.c
+++ b/block/blk-cgroup.c
@@ -928,7 +928,15 @@ struct cgroup_subsys blkio_cgrp_subsys = {
.css_offline = blkcg_css_offline,
.css_free = blkcg_css_free,
.can_attach = blkcg_can_attach,
- .base_cftypes = blkcg_files,
+ .legacy_cftypes = blkcg_files,
+#ifdef CONFIG_MEMCG
+ /*
+ * This ensures that, if available, memcg is automatically enabled
+ * together on the default hierarchy so that the owner cgroup can
+ * be retrieved from writeback pages.
+ */
+ .depends_on = 1 << memory_cgrp_id,
+#endif
};
EXPORT_SYMBOL_GPL(blkio_cgrp_subsys);
@@ -1120,7 +1128,8 @@ int blkcg_policy_register(struct blkcg_policy *pol)
/* everything is in place, add intf files for the new policy */
if (pol->cftypes)
- WARN_ON(cgroup_add_cftypes(&blkio_cgrp_subsys, pol->cftypes));
+ WARN_ON(cgroup_add_legacy_cftypes(&blkio_cgrp_subsys,
+ pol->cftypes));
ret = 0;
out_unlock:
mutex_unlock(&blkcg_pol_mutex);
diff --git a/block/blk-throttle.c b/block/blk-throttle.c
index 3fdb21a390c1..9273d0969ebd 100644
--- a/block/blk-throttle.c
+++ b/block/blk-throttle.c
@@ -412,13 +412,13 @@ static void throtl_pd_init(struct blkcg_gq *blkg)
int rw;
/*
- * If sane_hierarchy is enabled, we switch to properly hierarchical
+ * If on the default hierarchy, we switch to properly hierarchical
* behavior where limits on a given throtl_grp are applied to the
* whole subtree rather than just the group itself. e.g. If 16M
* read_bps limit is set on the root group, the whole system can't
* exceed 16M for the device.
*
- * If sane_hierarchy is not enabled, the broken flat hierarchy
+ * If not on the default hierarchy, the broken flat hierarchy
* behavior is retained where all throtl_grps are treated as if
* they're all separate root groups right below throtl_data.
* Limits of a group don't interact with limits of other groups
@@ -426,7 +426,7 @@ static void throtl_pd_init(struct blkcg_gq *blkg)
*/
parent_sq = &td->service_queue;
- if (cgroup_sane_behavior(blkg->blkcg->css.cgroup) && blkg->parent)
+ if (cgroup_on_dfl(blkg->blkcg->css.cgroup) && blkg->parent)
parent_sq = &blkg_to_tg(blkg->parent)->service_queue;
throtl_service_queue_init(&tg->service_queue, parent_sq);
diff --git a/include/linux/cgroup.h b/include/linux/cgroup.h
index 8a111dd42d7a..b5223c570eba 100644
--- a/include/linux/cgroup.h
+++ b/include/linux/cgroup.h
@@ -203,7 +203,15 @@ struct cgroup {
struct kernfs_node *kn; /* cgroup kernfs entry */
struct kernfs_node *populated_kn; /* kn for "cgroup.subtree_populated" */
- /* the bitmask of subsystems enabled on the child cgroups */
+ /*
+ * The bitmask of subsystems enabled on the child cgroups.
+ * ->subtree_control is the one configured through
+ * "cgroup.subtree_control" while ->child_subsys_mask is the
+ * effective one which may have more subsystems enabled.
+ * Controller knobs are made available iff it's enabled in
+ * ->subtree_control.
+ */
+ unsigned int subtree_control;
unsigned int child_subsys_mask;
/* Private pointers for each registered subsystem */
@@ -248,73 +256,9 @@ struct cgroup {
/* cgroup_root->flags */
enum {
- /*
- * Unfortunately, cgroup core and various controllers are riddled
- * with idiosyncrasies and pointless options. The following flag,
- * when set, will force sane behavior - some options are forced on,
- * others are disallowed, and some controllers will change their
- * hierarchical or other behaviors.
- *
- * The set of behaviors affected by this flag are still being
- * determined and developed and the mount option for this flag is
- * prefixed with __DEVEL__. The prefix will be dropped once we
- * reach the point where all behaviors are compatible with the
- * planned unified hierarchy, which will automatically turn on this
- * flag.
- *
- * The followings are the behaviors currently affected this flag.
- *
- * - Mount options "noprefix", "xattr", "clone_children",
- * "release_agent" and "name" are disallowed.
- *
- * - When mounting an existing superblock, mount options should
- * match.
- *
- * - Remount is disallowed.
- *
- * - rename(2) is disallowed.
- *
- * - "tasks" is removed. Everything should be at process
- * granularity. Use "cgroup.procs" instead.
- *
- * - "cgroup.procs" is not sorted. pids will be unique unless they
- * got recycled inbetween reads.
- *
- * - "release_agent" and "notify_on_release" are removed.
- * Replacement notification mechanism will be implemented.
- *
- * - "cgroup.clone_children" is removed.
- *
- * - "cgroup.subtree_populated" is available. Its value is 0 if
- * the cgroup and its descendants contain no task; otherwise, 1.
- * The file also generates kernfs notification which can be
- * monitored through poll and [di]notify when the value of the
- * file changes.
- *
- * - If mount is requested with sane_behavior but without any
- * subsystem, the default unified hierarchy is mounted.
- *
- * - cpuset: tasks will be kept in empty cpusets when hotplug happens
- * and take masks of ancestors with non-empty cpus/mems, instead of
- * being moved to an ancestor.
- *
- * - cpuset: a task can be moved into an empty cpuset, and again it
- * takes masks of ancestors.
- *
- * - memcg: use_hierarchy is on by default and the cgroup file for
- * the flag is not created.
- *
- * - blkcg: blk-throttle becomes properly hierarchical.
- *
- * - debug: disallowed on the default hierarchy.
- */
- CGRP_ROOT_SANE_BEHAVIOR = (1 << 0),
-
+ CGRP_ROOT_SANE_BEHAVIOR = (1 << 0), /* __DEVEL__sane_behavior specified */
CGRP_ROOT_NOPREFIX = (1 << 1), /* mounted subsystems have no named prefix */
CGRP_ROOT_XATTR = (1 << 2), /* supports extended attributes */
-
- /* mount options live below bit 16 */
- CGRP_ROOT_OPTION_MASK = (1 << 16) - 1,
};
/*
@@ -440,9 +384,11 @@ struct css_set {
enum {
CFTYPE_ONLY_ON_ROOT = (1 << 0), /* only create on root cgrp */
CFTYPE_NOT_ON_ROOT = (1 << 1), /* don't create on root cgrp */
- CFTYPE_INSANE = (1 << 2), /* don't create if sane_behavior */
CFTYPE_NO_PREFIX = (1 << 3), /* (DON'T USE FOR NEW FILES) no subsys prefix */
- CFTYPE_ONLY_ON_DFL = (1 << 4), /* only on default hierarchy */
+
+ /* internal flags, do not use outside cgroup core proper */
+ __CFTYPE_ONLY_ON_DFL = (1 << 16), /* only on default hierarchy */
+ __CFTYPE_NOT_ON_DFL = (1 << 17), /* not on default hierarchy */
};
#define MAX_CFTYPE_NAME 64
@@ -526,20 +472,64 @@ struct cftype {
extern struct cgroup_root cgrp_dfl_root;
extern struct css_set init_css_set;
+/**
+ * cgroup_on_dfl - test whether a cgroup is on the default hierarchy
+ * @cgrp: the cgroup of interest
+ *
+ * The default hierarchy is the v2 interface of cgroup and this function
+ * can be used to test whether a cgroup is on the default hierarchy for
+ * cases where a subsystem should behave differnetly depending on the
+ * interface version.
+ *
+ * The set of behaviors which change on the default hierarchy are still
+ * being determined and the mount option is prefixed with __DEVEL__.
+ *
+ * List of changed behaviors:
+ *
+ * - Mount options "noprefix", "xattr", "clone_children", "release_agent"
+ * and "name" are disallowed.
+ *
+ * - When mounting an existing superblock, mount options should match.
+ *
+ * - Remount is disallowed.
+ *
+ * - rename(2) is disallowed.
+ *
+ * - "tasks" is removed. Everything should be at process granularity. Use
+ * "cgroup.procs" instead.
+ *
+ * - "cgroup.procs" is not sorted. pids will be unique unless they got
+ * recycled inbetween reads.
+ *
+ * - "release_agent" and "notify_on_release" are removed. Replacement
+ * notification mechanism will be implemented.
+ *
+ * - "cgroup.clone_children" is removed.
+ *
+ * - "cgroup.subtree_populated" is available. Its value is 0 if the cgroup
+ * and its descendants contain no task; otherwise, 1. The file also
+ * generates kernfs notification which can be monitored through poll and
+ * [di]notify when the value of the file changes.
+ *
+ * - cpuset: tasks will be kept in empty cpusets when hotplug happens and
+ * take masks of ancestors with non-empty cpus/mems, instead of being
+ * moved to an ancestor.
+ *
+ * - cpuset: a task can be moved into an empty cpuset, and again it takes
+ * masks of ancestors.
+ *
+ * - memcg: use_hierarchy is on by default and the cgroup file for the flag
+ * is not created.
+ *
+ * - blkcg: blk-throttle becomes properly hierarchical.
+ *
+ * - debug: disallowed on the default hierarchy.
+ */
static inline bool cgroup_on_dfl(const struct cgroup *cgrp)
{
return cgrp->root == &cgrp_dfl_root;
}
-/*
- * See the comment above CGRP_ROOT_SANE_BEHAVIOR for details. This
- * function can be called as long as @cgrp is accessible.
- */
-static inline bool cgroup_sane_behavior(const struct cgroup *cgrp)
-{
- return cgrp->root->flags & CGRP_ROOT_SANE_BEHAVIOR;
-}
-
/* no synchronization, the result can only be used as a hint */
static inline bool cgroup_has_tasks(struct cgroup *cgrp)
{
@@ -602,7 +592,8 @@ static inline void pr_cont_cgroup_path(struct cgroup *cgrp)
char *task_cgroup_path(struct task_struct *task, char *buf, size_t buflen);
-int cgroup_add_cftypes(struct cgroup_subsys *ss, struct cftype *cfts);
+int cgroup_add_dfl_cftypes(struct cgroup_subsys *ss, struct cftype *cfts);
+int cgroup_add_legacy_cftypes(struct cgroup_subsys *ss, struct cftype *cfts);
int cgroup_rm_cftypes(struct cftype *cfts);
bool cgroup_is_descendant(struct cgroup *cgrp, struct cgroup *ancestor);
@@ -634,6 +625,7 @@ struct cgroup_subsys {
int (*css_online)(struct cgroup_subsys_state *css);
void (*css_offline)(struct cgroup_subsys_state *css);
void (*css_free)(struct cgroup_subsys_state *css);
+ void (*css_reset)(struct cgroup_subsys_state *css);
int (*can_attach)(struct cgroup_subsys_state *css,
struct cgroup_taskset *tset);
@@ -682,8 +674,21 @@ struct cgroup_subsys {
*/
struct list_head cfts;
- /* base cftypes, automatically registered with subsys itself */
- struct cftype *base_cftypes;
+ /*
+ * Base cftypes which are automatically registered. The two can
+ * point to the same array.
+ */
+ struct cftype *dfl_cftypes; /* for the default hierarchy */
+ struct cftype *legacy_cftypes; /* for the legacy hierarchies */
+
+ /*
+ * A subsystem may depend on other subsystems. When such subsystem
+ * is enabled on a cgroup, the depended-upon subsystems are enabled
+ * together if available. Subsystems enabled due to dependency are
+ * not visible to userland until explicitly enabled. The following
+ * specifies the mask of subsystems that this one depends on.
+ */
+ unsigned int depends_on;
};
#define SUBSYS(_x) extern struct cgroup_subsys _x ## _cgrp_subsys;
diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index aad41f06901b..7dc8788cfd52 100644
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -149,12 +149,14 @@ struct cgroup_root cgrp_dfl_root;
*/
static bool cgrp_dfl_root_visible;
+/*
+ * Set by the boot param of the same name and makes subsystems with NULL
+ * ->dfl_files to use ->legacy_files on the default hierarchy.
+ */
+static bool cgroup_legacy_files_on_dfl;
+
/* some controllers are not supported in the default hierarchy */
-static const unsigned int cgrp_dfl_root_inhibit_ss_mask = 0
-#ifdef CONFIG_CGROUP_DEBUG
- | (1 << debug_cgrp_id)
-#endif
- ;
+static unsigned int cgrp_dfl_root_inhibit_ss_mask;
/* The list of hierarchy roots */
@@ -180,13 +182,15 @@ static u64 css_serial_nr_next = 1;
*/
static int need_forkexit_callback __read_mostly;
-static struct cftype cgroup_base_files[];
+static struct cftype cgroup_dfl_base_files[];
+static struct cftype cgroup_legacy_base_files[];
static void cgroup_put(struct cgroup *cgrp);
static int rebind_subsystems(struct cgroup_root *dst_root,
unsigned int ss_mask);
static int cgroup_destroy_locked(struct cgroup *cgrp);
-static int create_css(struct cgroup *cgrp, struct cgroup_subsys *ss);
+static int create_css(struct cgroup *cgrp, struct cgroup_subsys *ss,
+ bool visible);
static void css_release(struct percpu_ref *ref);
static void kill_css(struct cgroup_subsys_state *css);
static int cgroup_addrm_files(struct cgroup *cgrp, struct cftype cfts[],
@@ -1037,6 +1041,58 @@ static void cgroup_put(struct cgroup *cgrp)
}
/**
+ * cgroup_refresh_child_subsys_mask - update child_subsys_mask
+ * @cgrp: the target cgroup
+ *
+ * On the default hierarchy, a subsystem may request other subsystems to be
+ * enabled together through its ->depends_on mask. In such cases, more
+ * subsystems than specified in "cgroup.subtree_control" may be enabled.
+ *
+ * This function determines which subsystems need to be enabled given the
+ * current @cgrp->subtree_control and records it in
+ * @cgrp->child_subsys_mask. The resulting mask is always a superset of
+ * @cgrp->subtree_control and follows the usual hierarchy rules.
+ */
+static void cgroup_refresh_child_subsys_mask(struct cgroup *cgrp)
+{
+ struct cgroup *parent = cgroup_parent(cgrp);
+ unsigned int cur_ss_mask = cgrp->subtree_control;
+ struct cgroup_subsys *ss;
+ int ssid;
+
+ lockdep_assert_held(&cgroup_mutex);
+
+ if (!cgroup_on_dfl(cgrp)) {
+ cgrp->child_subsys_mask = cur_ss_mask;
+ return;
+ }
+
+ while (true) {
+ unsigned int new_ss_mask = cur_ss_mask;
+
+ for_each_subsys(ss, ssid)
+ if (cur_ss_mask & (1 << ssid))
+ new_ss_mask |= ss->depends_on;
+
+ /*
+ * Mask out subsystems which aren't available. This can
+ * happen only if some depended-upon subsystems were bound
+ * to non-default hierarchies.
+ */
+ if (parent)
+ new_ss_mask &= parent->child_subsys_mask;
+ else
+ new_ss_mask &= cgrp->root->subsys_mask;
+
+ if (new_ss_mask == cur_ss_mask)
+ break;
+ cur_ss_mask = new_ss_mask;
+ }
+
+ cgrp->child_subsys_mask = cur_ss_mask;
+}
+
+/**
* cgroup_kn_unlock - unlocking helper for cgroup kernfs methods
* @kn: the kernfs_node being serviced
*
@@ -1208,12 +1264,15 @@ static int rebind_subsystems(struct cgroup_root *dst_root, unsigned int ss_mask)
up_write(&css_set_rwsem);
src_root->subsys_mask &= ~(1 << ssid);
- src_root->cgrp.child_subsys_mask &= ~(1 << ssid);
+ src_root->cgrp.subtree_control &= ~(1 << ssid);
+ cgroup_refresh_child_subsys_mask(&src_root->cgrp);
/* default hierarchy doesn't enable controllers by default */
dst_root->subsys_mask |= 1 << ssid;
- if (dst_root != &cgrp_dfl_root)
- dst_root->cgrp.child_subsys_mask |= 1 << ssid;
+ if (dst_root != &cgrp_dfl_root) {
+ dst_root->cgrp.subtree_control |= 1 << ssid;
+ cgroup_refresh_child_subsys_mask(&dst_root->cgrp);
+ }
if (ss->bind)
ss->bind(css);
@@ -1233,8 +1292,6 @@ static int cgroup_show_options(struct seq_file *seq,
for_each_subsys(ss, ssid)
if (root->subsys_mask & (1 << ssid))
seq_printf(seq, ",%s", ss->name);
- if (root->flags & CGRP_ROOT_SANE_BEHAVIOR)
- seq_puts(seq, ",sane_behavior");
if (root->flags & CGRP_ROOT_NOPREFIX)
seq_puts(seq, ",noprefix");
if (root->flags & CGRP_ROOT_XATTR)
@@ -1268,6 +1325,7 @@ static int parse_cgroupfs_options(char *data, struct cgroup_sb_opts *opts)
bool all_ss = false, one_ss = false;
unsigned int mask = -1U;
struct cgroup_subsys *ss;
+ int nr_opts = 0;
int i;
#ifdef CONFIG_CPUSETS
@@ -1277,6 +1335,8 @@ static int parse_cgroupfs_options(char *data, struct cgroup_sb_opts *opts)
memset(opts, 0, sizeof(*opts));
while ((token = strsep(&o, ",")) != NULL) {
+ nr_opts++;
+
if (!*token)
return -EINVAL;
if (!strcmp(token, "none")) {
@@ -1361,37 +1421,33 @@ static int parse_cgroupfs_options(char *data, struct cgroup_sb_opts *opts)
return -ENOENT;
}
- /* Consistency checks */
-
if (opts->flags & CGRP_ROOT_SANE_BEHAVIOR) {
pr_warn("sane_behavior: this is still under development and its behaviors will change, proceed at your own risk\n");
-
- if ((opts->flags & (CGRP_ROOT_NOPREFIX | CGRP_ROOT_XATTR)) ||
- opts->cpuset_clone_children || opts->release_agent ||
- opts->name) {
- pr_err("sane_behavior: noprefix, xattr, clone_children, release_agent and name are not allowed\n");
+ if (nr_opts != 1) {
+ pr_err("sane_behavior: no other mount options allowed\n");
return -EINVAL;
}
- } else {
- /*
- * If the 'all' option was specified select all the
- * subsystems, otherwise if 'none', 'name=' and a subsystem
- * name options were not specified, let's default to 'all'
- */
- if (all_ss || (!one_ss && !opts->none && !opts->name))
- for_each_subsys(ss, i)
- if (!ss->disabled)
- opts->subsys_mask |= (1 << i);
-
- /*
- * We either have to specify by name or by subsystems. (So
- * all empty hierarchies must have a name).
- */
- if (!opts->subsys_mask && !opts->name)
- return -EINVAL;
+ return 0;
}
/*
+ * If the 'all' option was specified select all the subsystems,
+ * otherwise if 'none', 'name=' and a subsystem name options were
+ * not specified, let's default to 'all'
+ */
+ if (all_ss || (!one_ss && !opts->none && !opts->name))
+ for_each_subsys(ss, i)
+ if (!ss->disabled)
+ opts->subsys_mask |= (1 << i);
+
+ /*
+ * We either have to specify by name or by subsystems. (So all
+ * empty hierarchies must have a name).
+ */
+ if (!opts->subsys_mask && !opts->name)
+ return -EINVAL;
+
+ /*
* Option noprefix was introduced just for backward compatibility
* with the old cpuset, so we allow noprefix only if mounting just
* the cpuset subsystem.
@@ -1399,7 +1455,6 @@ static int parse_cgroupfs_options(char *data, struct cgroup_sb_opts *opts)
if ((opts->flags & CGRP_ROOT_NOPREFIX) && (opts->subsys_mask & mask))
return -EINVAL;
-
/* Can't specify "none" and some subsystems */
if (opts->subsys_mask && opts->none)
return -EINVAL;
@@ -1414,8 +1469,8 @@ static int cgroup_remount(struct kernfs_root *kf_root, int *flags, char *data)
struct cgroup_sb_opts opts;
unsigned int added_mask, removed_mask;
- if (root->flags & CGRP_ROOT_SANE_BEHAVIOR) {
- pr_err("sane_behavior: remount is not allowed\n");
+ if (root == &cgrp_dfl_root) {
+ pr_err("remount is not allowed\n");
return -EINVAL;
}
@@ -1434,11 +1489,10 @@ static int cgroup_remount(struct kernfs_root *kf_root, int *flags, char *data)
removed_mask = root->subsys_mask & ~opts.subsys_mask;
/* Don't allow flags or name to change at remount */
- if (((opts.flags ^ root->flags) & CGRP_ROOT_OPTION_MASK) ||
+ if ((opts.flags ^ root->flags) ||
(opts.name && strcmp(opts.name, root->name))) {
pr_err("option or name mismatch, new: 0x%x \"%s\", old: 0x%x \"%s\"\n",
- opts.flags & CGRP_ROOT_OPTION_MASK, opts.name ?: "",
- root->flags & CGRP_ROOT_OPTION_MASK, root->name);
+ opts.flags, opts.name ?: "", root->flags, root->name);
ret = -EINVAL;
goto out_unlock;
}
@@ -1563,6 +1617,7 @@ static int cgroup_setup_root(struct cgroup_root *root, unsigned int ss_mask)
{
LIST_HEAD(tmp_links);
struct cgroup *root_cgrp = &root->cgrp;
+ struct cftype *base_files;
struct css_set *cset;
int i, ret;
@@ -1600,7 +1655,12 @@ static int cgroup_setup_root(struct cgroup_root *root, unsigned int ss_mask)
}
root_cgrp->kn = root->kf_root->kn;
- ret = cgroup_addrm_files(root_cgrp, cgroup_base_files, true);
+ if (root == &cgrp_dfl_root)
+ base_files = cgroup_dfl_base_files;
+ else
+ base_files = cgroup_legacy_base_files;
+
+ ret = cgroup_addrm_files(root_cgrp, base_files, true);
if (ret)
goto destroy_root;
@@ -1672,7 +1732,7 @@ static struct dentry *cgroup_mount(struct file_system_type *fs_type,
goto out_unlock;
/* look for a matching existing root */
- if (!opts.subsys_mask && !opts.none && !opts.name) {
+ if (opts.flags & CGRP_ROOT_SANE_BEHAVIOR) {
cgrp_dfl_root_visible = true;
root = &cgrp_dfl_root;
cgroup_get(&root->cgrp);
@@ -1730,15 +1790,8 @@ static struct dentry *cgroup_mount(struct file_system_type *fs_type,
goto out_unlock;
}
- if ((root->flags ^ opts.flags) & CGRP_ROOT_OPTION_MASK) {
- if ((root->flags | opts.flags) & CGRP_ROOT_SANE_BEHAVIOR) {
- pr_err("sane_behavior: new mount options should match the existing superblock\n");
- ret = -EINVAL;
- goto out_unlock;
- } else {
- pr_warn("new mount options do not match the existing superblock, will be ignored\n");
- }
- }
+ if (root->flags ^ opts.flags)
+ pr_warn("new mount options do not match the existing superblock, will be ignored\n");
/*
* We want to reuse @root whose lifetime is governed by its
@@ -2457,9 +2510,7 @@ static int cgroup_release_agent_show(struct seq_file *seq, void *v)
static int cgroup_sane_behavior_show(struct seq_file *seq, void *v)
{
- struct cgroup *cgrp = seq_css(seq)->cgroup;
-
- seq_printf(seq, "%d\n", cgroup_sane_behavior(cgrp));
+ seq_puts(seq, "0\n");
return 0;
}
@@ -2496,7 +2547,7 @@ static int cgroup_controllers_show(struct seq_file *seq, void *v)
{
struct cgroup *cgrp = seq_css(seq)->cgroup;
- cgroup_print_ss_mask(seq, cgroup_parent(cgrp)->child_subsys_mask);
+ cgroup_print_ss_mask(seq, cgroup_parent(cgrp)->subtree_control);
return 0;
}
@@ -2505,7 +2556,7 @@ static int cgroup_subtree_control_show(struct seq_file *seq, void *v)
{
struct cgroup *cgrp = seq_css(seq)->cgroup;
- cgroup_print_ss_mask(seq, cgrp->child_subsys_mask);
+ cgroup_print_ss_mask(seq, cgrp->subtree_control);
return 0;
}
@@ -2611,6 +2662,7 @@ static ssize_t cgroup_subtree_control_write(struct kernfs_open_file *of,
loff_t off)
{
unsigned int enable = 0, disable = 0;
+ unsigned int css_enable, css_disable, old_ctrl, new_ctrl;
struct cgroup *cgrp, *child;
struct cgroup_subsys *ss;
char *tok;
@@ -2650,11 +2702,26 @@ static ssize_t cgroup_subtree_control_write(struct kernfs_open_file *of,
for_each_subsys(ss, ssid) {
if (enable & (1 << ssid)) {
- if (cgrp->child_subsys_mask & (1 << ssid)) {
+ if (cgrp->subtree_control & (1 << ssid)) {
enable &= ~(1 << ssid);
continue;
}
+ /* unavailable or not enabled on the parent? */
+ if (!(cgrp_dfl_root.subsys_mask & (1 << ssid)) ||
+ (cgroup_parent(cgrp) &&
+ !(cgroup_parent(cgrp)->subtree_control & (1 << ssid)))) {
+ ret = -ENOENT;
+ goto out_unlock;
+ }
+
+ /*
+ * @ss is already enabled through dependency and
+ * we'll just make it visible. Skip draining.
+ */
+ if (cgrp->child_subsys_mask & (1 << ssid))
+ continue;
+
/*
* Because css offlining is asynchronous, userland
* might try to re-enable the same controller while
@@ -2677,23 +2744,15 @@ static ssize_t cgroup_subtree_control_write(struct kernfs_open_file *of,
return restart_syscall();
}
-
- /* unavailable or not enabled on the parent? */
- if (!(cgrp_dfl_root.subsys_mask & (1 << ssid)) ||
- (cgroup_parent(cgrp) &&
- !(cgroup_parent(cgrp)->child_subsys_mask & (1 << ssid)))) {
- ret = -ENOENT;
- goto out_unlock;
- }
} else if (disable & (1 << ssid)) {
- if (!(cgrp->child_subsys_mask & (1 << ssid))) {
+ if (!(cgrp->subtree_control & (1 << ssid))) {
disable &= ~(1 << ssid);
continue;
}
/* a child has it enabled? */
cgroup_for_each_live_child(child, cgrp) {
- if (child->child_subsys_mask & (1 << ssid)) {
+ if (child->subtree_control & (1 << ssid)) {
ret = -EBUSY;
goto out_unlock;
}
@@ -2707,7 +2766,7 @@ static ssize_t cgroup_subtree_control_write(struct kernfs_open_file *of,
}
/*
- * Except for the root, child_subsys_mask must be zero for a cgroup
+ * Except for the root, subtree_control must be zero for a cgroup
* with tasks so that child cgroups don't compete against tasks.
*/
if (enable && cgroup_parent(cgrp) && !list_empty(&cgrp->cset_links)) {
@@ -2716,36 +2775,75 @@ static ssize_t cgroup_subtree_control_write(struct kernfs_open_file *of,
}
/*
- * Create csses for enables and update child_subsys_mask. This
- * changes cgroup_e_css() results which in turn makes the
- * subsequent cgroup_update_dfl_csses() associate all tasks in the
- * subtree to the updated csses.
+ * Update subsys masks and calculate what needs to be done. More
+ * subsystems than specified may need to be enabled or disabled
+ * depending on subsystem dependencies.
+ */
+ cgrp->subtree_control |= enable;
+ cgrp->subtree_control &= ~disable;
+
+ old_ctrl = cgrp->child_subsys_mask;
+ cgroup_refresh_child_subsys_mask(cgrp);
+ new_ctrl = cgrp->child_subsys_mask;
+
+ css_enable = ~old_ctrl & new_ctrl;
+ css_disable = old_ctrl & ~new_ctrl;
+ enable |= css_enable;
+ disable |= css_disable;
+
+ /*
+ * Create new csses or make the existing ones visible. A css is
+ * created invisible if it's being implicitly enabled through
+ * dependency. An invisible css is made visible when the userland
+ * explicitly enables it.
*/
for_each_subsys(ss, ssid) {
if (!(enable & (1 << ssid)))
continue;
cgroup_for_each_live_child(child, cgrp) {
- ret = create_css(child, ss);
+ if (css_enable & (1 << ssid))
+ ret = create_css(child, ss,
+ cgrp->subtree_control & (1 << ssid));
+ else
+ ret = cgroup_populate_dir(child, 1 << ssid);
if (ret)
goto err_undo_css;
}
}
- cgrp->child_subsys_mask |= enable;
- cgrp->child_subsys_mask &= ~disable;
-
+ /*
+ * At this point, cgroup_e_css() results reflect the new csses
+ * making the following cgroup_update_dfl_csses() properly update
+ * css associations of all tasks in the subtree.
+ */
ret = cgroup_update_dfl_csses(cgrp);
if (ret)
goto err_undo_css;
- /* all tasks are now migrated away from the old csses, kill them */
+ /*
+ * All tasks are migrated out of disabled csses. Kill or hide
+ * them. A css is hidden when the userland requests it to be
+ * disabled while other subsystems are still depending on it. The
+ * css must not actively control resources and be in the vanilla
+ * state if it's made visible again later. Controllers which may
+ * be depended upon should provide ->css_reset() for this purpose.
+ */
for_each_subsys(ss, ssid) {
if (!(disable & (1 << ssid)))
continue;
- cgroup_for_each_live_child(child, cgrp)
- kill_css(cgroup_css(child, ss));
+ cgroup_for_each_live_child(child, cgrp) {
+ struct cgroup_subsys_state *css = cgroup_css(child, ss);
+
+ if (css_disable & (1 << ssid)) {
+ kill_css(css);
+ } else {
+ cgroup_clear_dir(child, 1 << ssid);
+ if (ss->css_reset)
+ ss->css_reset(css);
+ }
+ }
}
kernfs_activate(cgrp->kn);
@@ -2755,8 +2853,9 @@ out_unlock:
return ret ?: nbytes;
err_undo_css:
- cgrp->child_subsys_mask &= ~enable;
- cgrp->child_subsys_mask |= disable;
+ cgrp->subtree_control &= ~enable;
+ cgrp->subtree_control |= disable;
+ cgroup_refresh_child_subsys_mask(cgrp);
for_each_subsys(ss, ssid) {
if (!(enable & (1 << ssid)))
@@ -2764,8 +2863,14 @@ err_undo_css:
cgroup_for_each_live_child(child, cgrp) {
struct cgroup_subsys_state *css = cgroup_css(child, ss);
- if (css)
+
+ if (!css)
+ continue;
+
+ if (css_enable & (1 << ssid))
kill_css(css);
+ else
+ cgroup_clear_dir(child, 1 << ssid);
}
}
goto out_unlock;
@@ -2878,9 +2983,9 @@ static int cgroup_rename(struct kernfs_node *kn, struct kernfs_node *new_parent,
/*
* This isn't a proper migration and its usefulness is very
- * limited. Disallow if sane_behavior.
+ * limited. Disallow on the default hierarchy.
*/
- if (cgroup_sane_behavior(cgrp))
+ if (cgroup_on_dfl(cgrp))
return -EPERM;
/*
@@ -2964,9 +3069,9 @@ static int cgroup_addrm_files(struct cgroup *cgrp, struct cftype cfts[],
for (cft = cfts; cft->name[0] != '\0'; cft++) {
/* does cft->flags tell us to skip this file on @cgrp? */
- if ((cft->flags & CFTYPE_ONLY_ON_DFL) && !cgroup_on_dfl(cgrp))
+ if ((cft->flags & __CFTYPE_ONLY_ON_DFL) && !cgroup_on_dfl(cgrp))
continue;
- if ((cft->flags & CFTYPE_INSANE) && cgroup_sane_behavior(cgrp))
+ if ((cft->flags & __CFTYPE_NOT_ON_DFL) && cgroup_on_dfl(cgrp))
continue;
if ((cft->flags & CFTYPE_NOT_ON_ROOT) && !cgroup_parent(cgrp))
continue;
@@ -3024,6 +3129,9 @@ static void cgroup_exit_cftypes(struct cftype *cfts)
kfree(cft->kf_ops);
cft->kf_ops = NULL;
cft->ss = NULL;
+
+ /* revert flags set by cgroup core while adding @cfts */
+ cft->flags &= ~(__CFTYPE_ONLY_ON_DFL | __CFTYPE_NOT_ON_DFL);
}
}
@@ -3109,7 +3217,7 @@ int cgroup_rm_cftypes(struct cftype *cfts)
* 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, struct cftype *cfts)
+static int cgroup_add_cftypes(struct cgroup_subsys *ss, struct cftype *cfts)
{
int ret;
@@ -3135,6 +3243,40 @@ int cgroup_add_cftypes(struct cgroup_subsys *ss, struct cftype *cfts)
}
/**
+ * cgroup_add_dfl_cftypes - add an array of cftypes for default hierarchy
+ * @ss: target cgroup subsystem
+ * @cfts: zero-length name terminated array of cftypes
+ *
+ * Similar to cgroup_add_cftypes() but the added files are only used for
+ * the default hierarchy.
+ */
+int cgroup_add_dfl_cftypes(struct cgroup_subsys *ss, struct cftype *cfts)
+{
+ struct cftype *cft;
+
+ for (cft = cfts; cft && cft->name[0] != '\0'; cft++)
+ cft->flags |= __CFTYPE_ONLY_ON_DFL;
+ return cgroup_add_cftypes(ss, cfts);
+}
+
+/**
+ * cgroup_add_legacy_cftypes - add an array of cftypes for legacy hierarchies
+ * @ss: target cgroup subsystem
+ * @cfts: zero-length name terminated array of cftypes
+ *
+ * Similar to cgroup_add_cftypes() but the added files are only used for
+ * the legacy hierarchies.
+ */
+int cgroup_add_legacy_cftypes(struct cgroup_subsys *ss, struct cftype *cfts)
+{
+ struct cftype *cft;
+
+ for (cft = cfts; cft && cft->name[0] != '\0'; cft++)
+ cft->flags |= __CFTYPE_NOT_ON_DFL;
+ return cgroup_add_cftypes(ss, cfts);
+}
+
+/**
* cgroup_task_count - count the number of tasks in a cgroup.
* @cgrp: the cgroup in question
*
@@ -3699,8 +3841,9 @@ after:
*
* All this extra complexity was caused by the original implementation
* committing to an entirely unnecessary property. In the long term, we
- * want to do away with it. Explicitly scramble sort order if
- * sane_behavior so that no such expectation exists in the new interface.
+ * want to do away with it. Explicitly scramble sort order if on the
+ * default hierarchy so that no such expectation exists in the new
+ * interface.
*
* Scrambling is done by swapping every two consecutive bits, which is
* non-identity one-to-one mapping which disturbs sort order sufficiently.
@@ -3715,7 +3858,7 @@ static pid_t pid_fry(pid_t pid)
static pid_t cgroup_pid_fry(struct cgroup *cgrp, pid_t pid)
{
- if (cgroup_sane_behavior(cgrp))
+ if (cgroup_on_dfl(cgrp))
return pid_fry(pid);
else
return pid;
@@ -3818,7 +3961,7 @@ static int pidlist_array_load(struct cgroup *cgrp, enum cgroup_filetype type,
css_task_iter_end(&it);
length = n;
/* now sort & (if procs) strip out duplicates */
- if (cgroup_sane_behavior(cgrp))
+ if (cgroup_on_dfl(cgrp))
sort(array, length, sizeof(pid_t), fried_cmppid, NULL);
else
sort(array, length, sizeof(pid_t), cmppid, NULL);
@@ -4040,7 +4183,8 @@ static int cgroup_clone_children_write(struct cgroup_subsys_state *css,
return 0;
}
-static struct cftype cgroup_base_files[] = {
+/* cgroup core interface files for the default hierarchy */
+static struct cftype cgroup_dfl_base_files[] = {
{
.name = "cgroup.procs",
.seq_start = cgroup_pidlist_start,
@@ -4052,46 +4196,52 @@ static struct cftype cgroup_base_files[] = {
.mode = S_IRUGO | S_IWUSR,
},
{
- .name = "cgroup.clone_children",
- .flags = CFTYPE_INSANE,
- .read_u64 = cgroup_clone_children_read,
- .write_u64 = cgroup_clone_children_write,
- },
- {
- .name = "cgroup.sane_behavior",
- .flags = CFTYPE_ONLY_ON_ROOT,
- .seq_show = cgroup_sane_behavior_show,
- },
- {
.name = "cgroup.controllers",
- .flags = CFTYPE_ONLY_ON_DFL | CFTYPE_ONLY_ON_ROOT,
+ .flags = CFTYPE_ONLY_ON_ROOT,
.seq_show = cgroup_root_controllers_show,
},
{
.name = "cgroup.controllers",
- .flags = CFTYPE_ONLY_ON_DFL | CFTYPE_NOT_ON_ROOT,
+ .flags = CFTYPE_NOT_ON_ROOT,
.seq_show = cgroup_controllers_show,
},
{
.name = "cgroup.subtree_control",
- .flags = CFTYPE_ONLY_ON_DFL,
.seq_show = cgroup_subtree_control_show,
.write = cgroup_subtree_control_write,
},
{
.name = "cgroup.populated",
- .flags = CFTYPE_ONLY_ON_DFL | CFTYPE_NOT_ON_ROOT,
+ .flags = CFTYPE_NOT_ON_ROOT,
.seq_show = cgroup_populated_show,
},
+ { } /* terminate */
+};
- /*
- * Historical crazy stuff. These don't have "cgroup." prefix and
- * don't exist if sane_behavior. If you're depending on these, be
- * prepared to be burned.
- */
+/* cgroup core interface files for the legacy hierarchies */
+static struct cftype cgroup_legacy_base_files[] = {
+ {
+ .name = "cgroup.procs",
+ .seq_start = cgroup_pidlist_start,
+ .seq_next = cgroup_pidlist_next,
+ .seq_stop = cgroup_pidlist_stop,
+ .seq_show = cgroup_pidlist_show,
+ .private = CGROUP_FILE_PROCS,
+ .write = cgroup_procs_write,
+ .mode = S_IRUGO | S_IWUSR,
+ },
+ {
+ .name = "cgroup.clone_children",
+ .read_u64 = cgroup_clone_children_read,
+ .write_u64 = cgroup_clone_children_write,
+ },
+ {
+ .name = "cgroup.sane_behavior",
+ .flags = CFTYPE_ONLY_ON_ROOT,
+ .seq_show = cgroup_sane_behavior_show,
+ },
{
.name = "tasks",
- .flags = CFTYPE_INSANE, /* use "procs" instead */
.seq_start = cgroup_pidlist_start,
.seq_next = cgroup_pidlist_next,
.seq_stop = cgroup_pidlist_stop,
@@ -4102,13 +4252,12 @@ static struct cftype cgroup_base_files[] = {
},
{
.name = "notify_on_release",
- .flags = CFTYPE_INSANE,
.read_u64 = cgroup_read_notify_on_release,
.write_u64 = cgroup_write_notify_on_release,
},
{
.name = "release_agent",
- .flags = CFTYPE_INSANE | CFTYPE_ONLY_ON_ROOT,
+ .flags = CFTYPE_ONLY_ON_ROOT,
.seq_show = cgroup_release_agent_show,
.write = cgroup_release_agent_write,
.max_write_len = PATH_MAX - 1,
@@ -4316,12 +4465,14 @@ static void offline_css(struct cgroup_subsys_state *css)
* create_css - create a cgroup_subsys_state
* @cgrp: the cgroup new css will be associated with
* @ss: the subsys of new css
+ * @visible: whether to create control knobs for the new css or not
*
* Create a new css associated with @cgrp - @ss pair. On success, the new
- * css is online and installed in @cgrp with all interface files created.
- * Returns 0 on success, -errno on failure.
+ * css is online and installed in @cgrp with all interface files created if
+ * @visible. Returns 0 on success, -errno on failure.
*/
-static int create_css(struct cgroup *cgrp, struct cgroup_subsys *ss)
+static int create_css(struct cgroup *cgrp, struct cgroup_subsys *ss,
+ bool visible)
{
struct cgroup *parent = cgroup_parent(cgrp);
struct cgroup_subsys_state *parent_css = cgroup_css(parent, ss);
@@ -4345,9 +4496,11 @@ static int create_css(struct cgroup *cgrp, struct cgroup_subsys *ss)
goto err_free_percpu_ref;
css->id = err;
- err = cgroup_populate_dir(cgrp, 1 << ss->id);
- if (err)
- goto err_free_id;
+ if (visible) {
+ err = cgroup_populate_dir(cgrp, 1 << ss->id);
+ if (err)
+ goto err_free_id;
+ }
/* @css is ready to be brought online now, make it visible */
list_add_tail_rcu(&css->sibling, &parent_css->children);
@@ -4387,6 +4540,7 @@ static int cgroup_mkdir(struct kernfs_node *parent_kn, const char *name,
struct cgroup_root *root;
struct cgroup_subsys *ss;
struct kernfs_node *kn;
+ struct cftype *base_files;
int ssid, ret;
parent = cgroup_kn_lock_live(parent_kn);
@@ -4457,14 +4611,20 @@ static int cgroup_mkdir(struct kernfs_node *parent_kn, const char *name,
if (ret)
goto out_destroy;
- ret = cgroup_addrm_files(cgrp, cgroup_base_files, true);
+ if (cgroup_on_dfl(cgrp))
+ base_files = cgroup_dfl_base_files;
+ else
+ base_files = cgroup_legacy_base_files;
+
+ ret = cgroup_addrm_files(cgrp, base_files, true);
if (ret)
goto out_destroy;
/* let's create and online css's */
for_each_subsys(ss, ssid) {
if (parent->child_subsys_mask & (1 << ssid)) {
- ret = create_css(cgrp, ss);
+ ret = create_css(cgrp, ss,
+ parent->subtree_control & (1 << ssid));
if (ret)
goto out_destroy;
}
@@ -4472,10 +4632,12 @@ static int cgroup_mkdir(struct kernfs_node *parent_kn, const char *name,
/*
* On the default hierarchy, a child doesn't automatically inherit
- * child_subsys_mask from the parent. Each is configured manually.
+ * subtree_control from the parent. Each is configured manually.
*/
- if (!cgroup_on_dfl(cgrp))
- cgrp->child_subsys_mask = parent->child_subsys_mask;
+ if (!cgroup_on_dfl(cgrp)) {
+ cgrp->subtree_control = parent->subtree_control;
+ cgroup_refresh_child_subsys_mask(cgrp);
+ }
kernfs_activate(kn);
@@ -4738,8 +4900,7 @@ static void __init cgroup_init_subsys(struct cgroup_subsys *ss, bool early)
*/
int __init cgroup_init_early(void)
{
- static struct cgroup_sb_opts __initdata opts =
- { .flags = CGRP_ROOT_SANE_BEHAVIOR };
+ static struct cgroup_sb_opts __initdata opts;
struct cgroup_subsys *ss;
int i;
@@ -4777,7 +4938,8 @@ int __init cgroup_init(void)
unsigned long key;
int ssid, err;
- BUG_ON(cgroup_init_cftypes(NULL, cgroup_base_files));
+ BUG_ON(cgroup_init_cftypes(NULL, cgroup_dfl_base_files));
+ BUG_ON(cgroup_init_cftypes(NULL, cgroup_legacy_base_files));
mutex_lock(&cgroup_mutex);
@@ -4809,9 +4971,22 @@ int __init cgroup_init(void)
* disabled flag and cftype registration needs kmalloc,
* both of which aren't available during early_init.
*/
- if (!ss->disabled) {
- cgrp_dfl_root.subsys_mask |= 1 << ss->id;
- WARN_ON(cgroup_add_cftypes(ss, ss->base_cftypes));
+ if (ss->disabled)
+ continue;
+
+ cgrp_dfl_root.subsys_mask |= 1 << ss->id;
+
+ if (cgroup_legacy_files_on_dfl && !ss->dfl_cftypes)
+ ss->dfl_cftypes = ss->legacy_cftypes;
+
+ if (!ss->dfl_cftypes)
+ cgrp_dfl_root_inhibit_ss_mask |= 1 << ss->id;
+
+ if (ss->dfl_cftypes == ss->legacy_cftypes) {
+ WARN_ON(cgroup_add_cftypes(ss, ss->dfl_cftypes));
+ } else {
+ WARN_ON(cgroup_add_dfl_cftypes(ss, ss->dfl_cftypes));
+ WARN_ON(cgroup_add_legacy_cftypes(ss, ss->legacy_cftypes));
}
}
@@ -5207,6 +5382,14 @@ static int __init cgroup_disable(char *str)
}
__setup("cgroup_disable=", cgroup_disable);
+static int __init cgroup_set_legacy_files_on_dfl(char *str)
+{
+ printk("cgroup: using legacy files on the default hierarchy\n");
+ cgroup_legacy_files_on_dfl = true;
+ return 0;
+}
+__setup("cgroup__DEVEL__legacy_files_on_dfl", cgroup_set_legacy_files_on_dfl);
+
/**
* css_tryget_online_from_dir - get corresponding css from a cgroup dentry
* @dentry: directory dentry of interest
@@ -5401,6 +5584,6 @@ static struct cftype debug_files[] = {
struct cgroup_subsys debug_cgrp_subsys = {
.css_alloc = debug_css_alloc,
.css_free = debug_css_free,
- .base_cftypes = debug_files,
+ .legacy_cftypes = debug_files,
};
#endif /* CONFIG_CGROUP_DEBUG */
diff --git a/kernel/cgroup_freezer.c b/kernel/cgroup_freezer.c
index a79e40f9d700..92b98cc0ee76 100644
--- a/kernel/cgroup_freezer.c
+++ b/kernel/cgroup_freezer.c
@@ -480,5 +480,5 @@ struct cgroup_subsys freezer_cgrp_subsys = {
.css_free = freezer_css_free,
.attach = freezer_attach,
.fork = freezer_fork,
- .base_cftypes = files,
+ .legacy_cftypes = files,
};
diff --git a/kernel/cpuset.c b/kernel/cpuset.c
index 116a4164720a..22874d7cf2c0 100644
--- a/kernel/cpuset.c
+++ b/kernel/cpuset.c
@@ -76,8 +76,34 @@ struct cpuset {
struct cgroup_subsys_state css;
unsigned long flags; /* "unsigned long" so bitops work */
- cpumask_var_t cpus_allowed; /* CPUs allowed to tasks in cpuset */
- nodemask_t mems_allowed; /* Memory Nodes allowed to tasks */
+
+ /*
+ * On default hierarchy:
+ *
+ * The user-configured masks can only be changed by writing to
+ * cpuset.cpus and cpuset.mems, and won't be limited by the
+ * parent masks.
+ *
+ * The effective masks is the real masks that apply to the tasks
+ * in the cpuset. They may be changed if the configured masks are
+ * changed or hotplug happens.
+ *
+ * effective_mask == configured_mask & parent's effective_mask,
+ * and if it ends up empty, it will inherit the parent's mask.
+ *
+ *
+ * On legacy hierachy:
+ *
+ * The user-configured masks are always the same with effective masks.
+ */
+
+ /* user-configured CPUs and Memory Nodes allow to tasks */
+ cpumask_var_t cpus_allowed;
+ nodemask_t mems_allowed;
+
+ /* effective CPUs and Memory Nodes allow to tasks */
+ cpumask_var_t effective_cpus;
+ nodemask_t effective_mems;
/*
* This is old Memory Nodes tasks took on.
@@ -307,9 +333,9 @@ static struct file_system_type cpuset_fs_type = {
*/
static void guarantee_online_cpus(struct cpuset *cs, struct cpumask *pmask)
{
- while (!cpumask_intersects(cs->cpus_allowed, cpu_online_mask))
+ while (!cpumask_intersects(cs->effective_cpus, cpu_online_mask))
cs = parent_cs(cs);
- cpumask_and(pmask, cs->cpus_allowed, cpu_online_mask);
+ cpumask_and(pmask, cs->effective_cpus, cpu_online_mask);
}
/*
@@ -325,9 +351,9 @@ static void guarantee_online_cpus(struct cpuset *cs, struct cpumask *pmask)
*/
static void guarantee_online_mems(struct cpuset *cs, nodemask_t *pmask)
{
- while (!nodes_intersects(cs->mems_allowed, node_states[N_MEMORY]))
+ while (!nodes_intersects(cs->effective_mems, node_states[N_MEMORY]))
cs = parent_cs(cs);
- nodes_and(*pmask, cs->mems_allowed, node_states[N_MEMORY]);
+ nodes_and(*pmask, cs->effective_mems, node_states[N_MEMORY]);
}
/*
@@ -376,13 +402,20 @@ static struct cpuset *alloc_trial_cpuset(struct cpuset *cs)
if (!trial)
return NULL;
- if (!alloc_cpumask_var(&trial->cpus_allowed, GFP_KERNEL)) {
- kfree(trial);
- return NULL;
- }
- cpumask_copy(trial->cpus_allowed, cs->cpus_allowed);
+ if (!alloc_cpumask_var(&trial->cpus_allowed, GFP_KERNEL))
+ goto free_cs;
+ if (!alloc_cpumask_var(&trial->effective_cpus, GFP_KERNEL))
+ goto free_cpus;
+ cpumask_copy(trial->cpus_allowed, cs->cpus_allowed);
+ cpumask_copy(trial->effective_cpus, cs->effective_cpus);
return trial;
+
+free_cpus:
+ free_cpumask_var(trial->cpus_allowed);
+free_cs:
+ kfree(trial);
+ return NULL;
}
/**
@@ -391,6 +424,7 @@ static struct cpuset *alloc_trial_cpuset(struct cpuset *cs)
*/
static void free_trial_cpuset(struct cpuset *trial)
{
+ free_cpumask_var(trial->effective_cpus);
free_cpumask_var(trial->cpus_allowed);
kfree(trial);
}
@@ -436,9 +470,9 @@ static int validate_change(struct cpuset *cur, struct cpuset *trial)
par = parent_cs(cur);
- /* We must be a subset of our parent cpuset */
+ /* On legacy hiearchy, we must be a subset of our parent cpuset. */
ret = -EACCES;
- if (!is_cpuset_subset(trial, par))
+ if (!cgroup_on_dfl(cur->css.cgroup) && !is_cpuset_subset(trial, par))
goto out;
/*
@@ -480,11 +514,11 @@ out:
#ifdef CONFIG_SMP
/*
* Helper routine for generate_sched_domains().
- * Do cpusets a, b have overlapping cpus_allowed masks?
+ * Do cpusets a, b have overlapping effective cpus_allowed masks?
*/
static int cpusets_overlap(struct cpuset *a, struct cpuset *b)
{
- return cpumask_intersects(a->cpus_allowed, b->cpus_allowed);
+ return cpumask_intersects(a->effective_cpus, b->effective_cpus);
}
static void
@@ -601,7 +635,7 @@ static int generate_sched_domains(cpumask_var_t **domains,
*dattr = SD_ATTR_INIT;
update_domain_attr_tree(dattr, &top_cpuset);
}
- cpumask_copy(doms[0], top_cpuset.cpus_allowed);
+ cpumask_copy(doms[0], top_cpuset.effective_cpus);
goto done;
}
@@ -705,7 +739,7 @@ restart:
struct cpuset *b = csa[j];
if (apn == b->pn) {
- cpumask_or(dp, dp, b->cpus_allowed);
+ cpumask_or(dp, dp, b->effective_cpus);
if (dattr)
update_domain_attr_tree(dattr + nslot, b);
@@ -757,7 +791,7 @@ static void rebuild_sched_domains_locked(void)
* passing doms with offlined cpu to partition_sched_domains().
* Anyways, hotplug work item will rebuild sched domains.
*/
- if (!cpumask_equal(top_cpuset.cpus_allowed, cpu_active_mask))
+ if (!cpumask_equal(top_cpuset.effective_cpus, cpu_active_mask))
goto out;
/* Generate domain masks and attrs */
@@ -781,45 +815,6 @@ void rebuild_sched_domains(void)
mutex_unlock(&cpuset_mutex);
}
-/*
- * effective_cpumask_cpuset - return nearest ancestor with non-empty cpus
- * @cs: the cpuset in interest
- *
- * A cpuset's effective cpumask is the cpumask of the nearest ancestor
- * with non-empty cpus. We use effective cpumask whenever:
- * - we update tasks' cpus_allowed. (they take on the ancestor's cpumask
- * if the cpuset they reside in has no cpus)
- * - we want to retrieve task_cs(tsk)'s cpus_allowed.
- *
- * Called with cpuset_mutex held. cpuset_cpus_allowed_fallback() is an
- * exception. See comments there.
- */
-static struct cpuset *effective_cpumask_cpuset(struct cpuset *cs)
-{
- while (cpumask_empty(cs->cpus_allowed))
- cs = parent_cs(cs);
- return cs;
-}
-
-/*
- * effective_nodemask_cpuset - return nearest ancestor with non-empty mems
- * @cs: the cpuset in interest
- *
- * A cpuset's effective nodemask is the nodemask of the nearest ancestor
- * with non-empty memss. We use effective nodemask whenever:
- * - we update tasks' mems_allowed. (they take on the ancestor's nodemask
- * if the cpuset they reside in has no mems)
- * - we want to retrieve task_cs(tsk)'s mems_allowed.
- *
- * Called with cpuset_mutex held.
- */
-static struct cpuset *effective_nodemask_cpuset(struct cpuset *cs)
-{
- while (nodes_empty(cs->mems_allowed))
- cs = parent_cs(cs);
- return cs;
-}
-
/**
* update_tasks_cpumask - Update the cpumasks of tasks in the cpuset.
* @cs: the cpuset in which each task's cpus_allowed mask needs to be changed
@@ -830,53 +825,80 @@ static struct cpuset *effective_nodemask_cpuset(struct cpuset *cs)
*/
static void update_tasks_cpumask(struct cpuset *cs)
{
- struct cpuset *cpus_cs = effective_cpumask_cpuset(cs);
struct css_task_iter it;
struct task_struct *task;
css_task_iter_start(&cs->css, &it);
while ((task = css_task_iter_next(&it)))
- set_cpus_allowed_ptr(task, cpus_cs->cpus_allowed);
+ set_cpus_allowed_ptr(task, cs->effective_cpus);
css_task_iter_end(&it);
}
/*
- * update_tasks_cpumask_hier - Update the cpumasks of tasks in the hierarchy.
- * @root_cs: the root cpuset of the hierarchy
- * @update_root: update root cpuset or not?
+ * update_cpumasks_hier - Update effective cpumasks and tasks in the subtree
+ * @cs: the cpuset to consider
+ * @new_cpus: temp variable for calculating new effective_cpus
+ *
+ * When congifured cpumask is changed, the effective cpumasks of this cpuset
+ * and all its descendants need to be updated.
*
- * This will update cpumasks of tasks in @root_cs and all other empty cpusets
- * which take on cpumask of @root_cs.
+ * On legacy hierachy, effective_cpus will be the same with cpu_allowed.
*
* Called with cpuset_mutex held
*/
-static void update_tasks_cpumask_hier(struct cpuset *root_cs, bool update_root)
+static void update_cpumasks_hier(struct cpuset *cs, struct cpumask *new_cpus)
{
struct cpuset *cp;
struct cgroup_subsys_state *pos_css;
+ bool need_rebuild_sched_domains = false;
rcu_read_lock();
- cpuset_for_each_descendant_pre(cp, pos_css, root_cs) {
- if (cp == root_cs) {
- if (!update_root)
- continue;
- } else {
- /* skip the whole subtree if @cp have some CPU */
- if (!cpumask_empty(cp->cpus_allowed)) {
- pos_css = css_rightmost_descendant(pos_css);
- continue;
- }
+ cpuset_for_each_descendant_pre(cp, pos_css, cs) {
+ struct cpuset *parent = parent_cs(cp);
+
+ cpumask_and(new_cpus, cp->cpus_allowed, parent->effective_cpus);
+
+ /*
+ * If it becomes empty, inherit the effective mask of the
+ * parent, which is guaranteed to have some CPUs.
+ */
+ if (cpumask_empty(new_cpus))
+ cpumask_copy(new_cpus, parent->effective_cpus);
+
+ /* Skip the whole subtree if the cpumask remains the same. */
+ if (cpumask_equal(new_cpus, cp->effective_cpus)) {
+ pos_css = css_rightmost_descendant(pos_css);
+ continue;
}
+
if (!css_tryget_online(&cp->css))
continue;
rcu_read_unlock();
+ mutex_lock(&callback_mutex);
+ cpumask_copy(cp->effective_cpus, new_cpus);
+ mutex_unlock(&callback_mutex);
+
+ WARN_ON(!cgroup_on_dfl(cp->css.cgroup) &&
+ !cpumask_equal(cp->cpus_allowed, cp->effective_cpus));
+
update_tasks_cpumask(cp);
+ /*
+ * If the effective cpumask of any non-empty cpuset is changed,
+ * we need to rebuild sched domains.
+ */
+ if (!cpumask_empty(cp->cpus_allowed) &&
+ is_sched_load_balance(cp))
+ need_rebuild_sched_domains = true;
+
rcu_read_lock();
css_put(&cp->css);
}
rcu_read_unlock();
+
+ if (need_rebuild_sched_domains)
+ rebuild_sched_domains_locked();
}
/**
@@ -889,7 +911,6 @@ static int update_cpumask(struct cpuset *cs, struct cpuset *trialcs,
const char *buf)
{
int retval;
- int is_load_balanced;
/* top_cpuset.cpus_allowed tracks cpu_online_mask; it's read-only */
if (cs == &top_cpuset)
@@ -908,7 +929,8 @@ static int update_cpumask(struct cpuset *cs, struct cpuset *trialcs,
if (retval < 0)
return retval;
- if (!cpumask_subset(trialcs->cpus_allowed, cpu_active_mask))
+ if (!cpumask_subset(trialcs->cpus_allowed,
+ top_cpuset.cpus_allowed))
return -EINVAL;
}
@@ -920,16 +942,12 @@ static int update_cpumask(struct cpuset *cs, struct cpuset *trialcs,
if (retval < 0)
return retval;
- is_load_balanced = is_sched_load_balance(trialcs);
-
mutex_lock(&callback_mutex);
cpumask_copy(cs->cpus_allowed, trialcs->cpus_allowed);
mutex_unlock(&callback_mutex);
- update_tasks_cpumask_hier(cs, true);
-
- if (is_load_balanced)
- rebuild_sched_domains_locked();
+ /* use trialcs->cpus_allowed as a temp variable */
+ update_cpumasks_hier(cs, trialcs->cpus_allowed);
return 0;
}
@@ -951,15 +969,13 @@ static void cpuset_migrate_mm(struct mm_struct *mm, const nodemask_t *from,
const nodemask_t *to)
{
struct task_struct *tsk = current;
- struct cpuset *mems_cs;
tsk->mems_allowed = *to;
do_migrate_pages(mm, from, to, MPOL_MF_MOVE_ALL);
rcu_read_lock();
- mems_cs = effective_nodemask_cpuset(task_cs(tsk));
- guarantee_online_mems(mems_cs, &tsk->mems_allowed);
+ guarantee_online_mems(task_cs(tsk), &tsk->mems_allowed);
rcu_read_unlock();
}
@@ -1028,13 +1044,12 @@ static void *cpuset_being_rebound;
static void update_tasks_nodemask(struct cpuset *cs)
{
static nodemask_t newmems; /* protected by cpuset_mutex */
- struct cpuset *mems_cs = effective_nodemask_cpuset(cs);
struct css_task_iter it;
struct task_struct *task;
cpuset_being_rebound = cs; /* causes mpol_dup() rebind */
- guarantee_online_mems(mems_cs, &newmems);
+ guarantee_online_mems(cs, &newmems);
/*
* The mpol_rebind_mm() call takes mmap_sem, which we couldn't
@@ -1077,36 +1092,52 @@ static void update_tasks_nodemask(struct cpuset *cs)
}
/*
- * update_tasks_nodemask_hier - Update the nodemasks of tasks in the hierarchy.
- * @cs: the root cpuset of the hierarchy
- * @update_root: update the root cpuset or not?
+ * update_nodemasks_hier - Update effective nodemasks and tasks in the subtree
+ * @cs: the cpuset to consider
+ * @new_mems: a temp variable for calculating new effective_mems
*
- * This will update nodemasks of tasks in @root_cs and all other empty cpusets
- * which take on nodemask of @root_cs.
+ * When configured nodemask is changed, the effective nodemasks of this cpuset
+ * and all its descendants need to be updated.
+ *
+ * On legacy hiearchy, effective_mems will be the same with mems_allowed.
*
* Called with cpuset_mutex held
*/
-static void update_tasks_nodemask_hier(struct cpuset *root_cs, bool update_root)
+static void update_nodemasks_hier(struct cpuset *cs, nodemask_t *new_mems)
{
struct cpuset *cp;
struct cgroup_subsys_state *pos_css;
rcu_read_lock();
- cpuset_for_each_descendant_pre(cp, pos_css, root_cs) {
- if (cp == root_cs) {
- if (!update_root)
- continue;
- } else {
- /* skip the whole subtree if @cp have some CPU */
- if (!nodes_empty(cp->mems_allowed)) {
- pos_css = css_rightmost_descendant(pos_css);
- continue;
- }
+ cpuset_for_each_descendant_pre(cp, pos_css, cs) {
+ struct cpuset *parent = parent_cs(cp);
+
+ nodes_and(*new_mems, cp->mems_allowed, parent->effective_mems);
+
+ /*
+ * If it becomes empty, inherit the effective mask of the
+ * parent, which is guaranteed to have some MEMs.
+ */
+ if (nodes_empty(*new_mems))
+ *new_mems = parent->effective_mems;
+
+ /* Skip the whole subtree if the nodemask remains the same. */
+ if (nodes_equal(*new_mems, cp->effective_mems)) {
+ pos_css = css_rightmost_descendant(pos_css);
+ continue;
}
+
if (!css_tryget_online(&cp->css))
continue;
rcu_read_unlock();
+ mutex_lock(&callback_mutex);
+ cp->effective_mems = *new_mems;
+ mutex_unlock(&callback_mutex);
+
+ WARN_ON(!cgroup_on_dfl(cp->css.cgroup) &&
+ !nodes_equal(cp->mems_allowed, cp->effective_mems));
+
update_tasks_nodemask(cp);
rcu_read_lock();
@@ -1156,8 +1187,8 @@ static int update_nodemask(struct cpuset *cs, struct cpuset *trialcs,
goto done;
if (!nodes_subset(trialcs->mems_allowed,
- node_states[N_MEMORY])) {
- retval = -EINVAL;
+ top_cpuset.mems_allowed)) {
+ retval = -EINVAL;
goto done;
}
}
@@ -1174,7 +1205,8 @@ static int update_nodemask(struct cpuset *cs, struct cpuset *trialcs,
cs->mems_allowed = trialcs->mems_allowed;
mutex_unlock(&callback_mutex);
- update_tasks_nodemask_hier(cs, true);
+ /* use trialcs->mems_allowed as a temp variable */
+ update_nodemasks_hier(cs, &cs->mems_allowed);
done:
return retval;
}
@@ -1389,12 +1421,9 @@ static int cpuset_can_attach(struct cgroup_subsys_state *css,
mutex_lock(&cpuset_mutex);
- /*
- * We allow to move tasks into an empty cpuset if sane_behavior
- * flag is set.
- */
+ /* allow moving tasks into an empty cpuset if on default hierarchy */
ret = -ENOSPC;
- if (!cgroup_sane_behavior(css->cgroup) &&
+ if (!cgroup_on_dfl(css->cgroup) &&
(cpumask_empty(cs->cpus_allowed) || nodes_empty(cs->mems_allowed)))
goto out_unlock;
@@ -1452,8 +1481,6 @@ static void cpuset_attach(struct cgroup_subsys_state *css,
struct task_struct *leader = cgroup_taskset_first(tset);
struct cpuset *cs = css_cs(css);
struct cpuset *oldcs = cpuset_attach_old_cs;
- struct cpuset *cpus_cs = effective_cpumask_cpuset(cs);
- struct cpuset *mems_cs = effective_nodemask_cpuset(cs);
mutex_lock(&cpuset_mutex);
@@ -1461,9 +1488,9 @@ static void cpuset_attach(struct cgroup_subsys_state *css,
if (cs == &top_cpuset)
cpumask_copy(cpus_attach, cpu_possible_mask);
else
- guarantee_online_cpus(cpus_cs, cpus_attach);
+ guarantee_online_cpus(cs, cpus_attach);
- guarantee_online_mems(mems_cs, &cpuset_attach_nodemask_to);
+ guarantee_online_mems(cs, &cpuset_attach_nodemask_to);
cgroup_taskset_for_each(task, tset) {
/*
@@ -1480,11 +1507,9 @@ static void cpuset_attach(struct cgroup_subsys_state *css,
* Change mm, possibly for multiple threads in a threadgroup. This is
* expensive and may sleep.
*/
- cpuset_attach_nodemask_to = cs->mems_allowed;
+ cpuset_attach_nodemask_to = cs->effective_mems;
mm = get_task_mm(leader);
if (mm) {
- struct cpuset *mems_oldcs = effective_nodemask_cpuset(oldcs);
-
mpol_rebind_mm(mm, &cpuset_attach_nodemask_to);
/*
@@ -1495,7 +1520,7 @@ static void cpuset_attach(struct cgroup_subsys_state *css,
* mm from.
*/
if (is_memory_migrate(cs)) {
- cpuset_migrate_mm(mm, &mems_oldcs->old_mems_allowed,
+ cpuset_migrate_mm(mm, &oldcs->old_mems_allowed,
&cpuset_attach_nodemask_to);
}
mmput(mm);
@@ -1516,6 +1541,8 @@ typedef enum {
FILE_MEMORY_MIGRATE,
FILE_CPULIST,
FILE_MEMLIST,
+ FILE_EFFECTIVE_CPULIST,
+ FILE_EFFECTIVE_MEMLIST,
FILE_CPU_EXCLUSIVE,
FILE_MEM_EXCLUSIVE,
FILE_MEM_HARDWALL,
@@ -1694,6 +1721,12 @@ static int cpuset_common_seq_show(struct seq_file *sf, void *v)
case FILE_MEMLIST:
s += nodelist_scnprintf(s, count, cs->mems_allowed);
break;
+ case FILE_EFFECTIVE_CPULIST:
+ s += cpulist_scnprintf(s, count, cs->effective_cpus);
+ break;
+ case FILE_EFFECTIVE_MEMLIST:
+ s += nodelist_scnprintf(s, count, cs->effective_mems);
+ break;
default:
ret = -EINVAL;
goto out_unlock;
@@ -1779,6 +1812,18 @@ static struct cftype files[] = {
},
{
+ .name = "effective_cpus",
+ .seq_show = cpuset_common_seq_show,
+ .private = FILE_EFFECTIVE_CPULIST,
+ },
+
+ {
+ .name = "effective_mems",
+ .seq_show = cpuset_common_seq_show,
+ .private = FILE_EFFECTIVE_MEMLIST,
+ },
+
+ {
.name = "cpu_exclusive",
.read_u64 = cpuset_read_u64,
.write_u64 = cpuset_write_u64,
@@ -1869,18 +1914,26 @@ cpuset_css_alloc(struct cgroup_subsys_state *parent_css)
cs = kzalloc(sizeof(*cs), GFP_KERNEL);
if (!cs)
return ERR_PTR(-ENOMEM);
- if (!alloc_cpumask_var(&cs->cpus_allowed, GFP_KERNEL)) {
- kfree(cs);
- return ERR_PTR(-ENOMEM);
- }
+ if (!alloc_cpumask_var(&cs->cpus_allowed, GFP_KERNEL))
+ goto free_cs;
+ if (!alloc_cpumask_var(&cs->effective_cpus, GFP_KERNEL))
+ goto free_cpus;
set_bit(CS_SCHED_LOAD_BALANCE, &cs->flags);
cpumask_clear(cs->cpus_allowed);
nodes_clear(cs->mems_allowed);
+ cpumask_clear(cs->effective_cpus);
+ nodes_clear(cs->effective_mems);
fmeter_init(&cs->fmeter);
cs->relax_domain_level = -1;
return &cs->css;
+
+free_cpus:
+ free_cpumask_var(cs->cpus_allowed);
+free_cs:
+ kfree(cs);
+ return ERR_PTR(-ENOMEM);
}
static int cpuset_css_online(struct cgroup_subsys_state *css)
@@ -1903,6 +1956,13 @@ static int cpuset_css_online(struct cgroup_subsys_state *css)
cpuset_inc();
+ mutex_lock(&callback_mutex);
+ if (cgroup_on_dfl(cs->css.cgroup)) {
+ cpumask_copy(cs->effective_cpus, parent->effective_cpus);
+ cs->effective_mems = parent->effective_mems;
+ }
+ mutex_unlock(&callback_mutex);
+
if (!test_bit(CGRP_CPUSET_CLONE_CHILDREN, &css->cgroup->flags))
goto out_unlock;
@@ -1962,20 +2022,40 @@ static void cpuset_css_free(struct cgroup_subsys_state *css)
{
struct cpuset *cs = css_cs(css);
+ free_cpumask_var(cs->effective_cpus);
free_cpumask_var(cs->cpus_allowed);
kfree(cs);
}
+static void cpuset_bind(struct cgroup_subsys_state *root_css)
+{
+ mutex_lock(&cpuset_mutex);
+ mutex_lock(&callback_mutex);
+
+ if (cgroup_on_dfl(root_css->cgroup)) {
+ cpumask_copy(top_cpuset.cpus_allowed, cpu_possible_mask);
+ top_cpuset.mems_allowed = node_possible_map;
+ } else {
+ cpumask_copy(top_cpuset.cpus_allowed,
+ top_cpuset.effective_cpus);
+ top_cpuset.mems_allowed = top_cpuset.effective_mems;
+ }
+
+ mutex_unlock(&callback_mutex);
+ mutex_unlock(&cpuset_mutex);
+}
+
struct cgroup_subsys cpuset_cgrp_subsys = {
- .css_alloc = cpuset_css_alloc,
- .css_online = cpuset_css_online,
- .css_offline = cpuset_css_offline,
- .css_free = cpuset_css_free,
- .can_attach = cpuset_can_attach,
- .cancel_attach = cpuset_cancel_attach,
- .attach = cpuset_attach,
- .base_cftypes = files,
- .early_init = 1,
+ .css_alloc = cpuset_css_alloc,
+ .css_online = cpuset_css_online,
+ .css_offline = cpuset_css_offline,
+ .css_free = cpuset_css_free,
+ .can_attach = cpuset_can_attach,
+ .cancel_attach = cpuset_cancel_attach,
+ .attach = cpuset_attach,
+ .bind = cpuset_bind,
+ .legacy_cftypes = files,
+ .early_init = 1,
};
/**
@@ -1990,9 +2070,13 @@ int __init cpuset_init(void)
if (!alloc_cpumask_var(&top_cpuset.cpus_allowed, GFP_KERNEL))
BUG();
+ if (!alloc_cpumask_var(&top_cpuset.effective_cpus, GFP_KERNEL))
+ BUG();
cpumask_setall(top_cpuset.cpus_allowed);
nodes_setall(top_cpuset.mems_allowed);
+ cpumask_setall(top_cpuset.effective_cpus);
+ nodes_setall(top_cpuset.effective_mems);
fmeter_init(&top_cpuset.fmeter);
set_bit(CS_SCHED_LOAD_BALANCE, &top_cpuset.flags);
@@ -2035,6 +2119,66 @@ static void remove_tasks_in_empty_cpuset(struct cpuset *cs)
}
}
+static void
+hotplug_update_tasks_legacy(struct cpuset *cs,
+ struct cpumask *new_cpus, nodemask_t *new_mems,
+ bool cpus_updated, bool mems_updated)
+{
+ bool is_empty;
+
+ mutex_lock(&callback_mutex);
+ cpumask_copy(cs->cpus_allowed, new_cpus);
+ cpumask_copy(cs->effective_cpus, new_cpus);
+ cs->mems_allowed = *new_mems;
+ cs->effective_mems = *new_mems;
+ mutex_unlock(&callback_mutex);
+
+ /*
+ * Don't call update_tasks_cpumask() if the cpuset becomes empty,
+ * as the tasks will be migratecd to an ancestor.
+ */
+ if (cpus_updated && !cpumask_empty(cs->cpus_allowed))
+ update_tasks_cpumask(cs);
+ if (mems_updated && !nodes_empty(cs->mems_allowed))
+ update_tasks_nodemask(cs);
+
+ is_empty = cpumask_empty(cs->cpus_allowed) ||
+ nodes_empty(cs->mems_allowed);
+
+ mutex_unlock(&cpuset_mutex);
+
+ /*
+ * Move tasks to the nearest ancestor with execution resources,
+ * This is full cgroup operation which will also call back into
+ * cpuset. Should be done outside any lock.
+ */
+ if (is_empty)
+ remove_tasks_in_empty_cpuset(cs);
+
+ mutex_lock(&cpuset_mutex);
+}
+
+static void
+hotplug_update_tasks(struct cpuset *cs,
+ struct cpumask *new_cpus, nodemask_t *new_mems,
+ bool cpus_updated, bool mems_updated)
+{
+ if (cpumask_empty(new_cpus))
+ cpumask_copy(new_cpus, parent_cs(cs)->effective_cpus);
+ if (nodes_empty(*new_mems))
+ *new_mems = parent_cs(cs)->effective_mems;
+
+ mutex_lock(&callback_mutex);
+ cpumask_copy(cs->effective_cpus, new_cpus);
+ cs->effective_mems = *new_mems;
+ mutex_unlock(&callback_mutex);
+
+ if (cpus_updated)
+ update_tasks_cpumask(cs);
+ if (mems_updated)
+ update_tasks_nodemask(cs);
+}
+
/**
* cpuset_hotplug_update_tasks - update tasks in a cpuset for hotunplug
* @cs: cpuset in interest
@@ -2045,11 +2189,10 @@ static void remove_tasks_in_empty_cpuset(struct cpuset *cs)
*/
static void cpuset_hotplug_update_tasks(struct cpuset *cs)
{
- static cpumask_t off_cpus;
- static nodemask_t off_mems;
- bool is_empty;
- bool sane = cgroup_sane_behavior(cs->css.cgroup);
-
+ static cpumask_t new_cpus;
+ static nodemask_t new_mems;
+ bool cpus_updated;
+ bool mems_updated;
retry:
wait_event(cpuset_attach_wq, cs->attach_in_progress == 0);
@@ -2064,51 +2207,20 @@ retry:
goto retry;
}
- cpumask_andnot(&off_cpus, cs->cpus_allowed, top_cpuset.cpus_allowed);
- nodes_andnot(off_mems, cs->mems_allowed, top_cpuset.mems_allowed);
-
- mutex_lock(&callback_mutex);
- cpumask_andnot(cs->cpus_allowed, cs->cpus_allowed, &off_cpus);
- mutex_unlock(&callback_mutex);
-
- /*
- * If sane_behavior flag is set, we need to update tasks' cpumask
- * for empty cpuset to take on ancestor's cpumask. Otherwise, don't
- * call update_tasks_cpumask() if the cpuset becomes empty, as
- * the tasks in it will be migrated to an ancestor.
- */
- if ((sane && cpumask_empty(cs->cpus_allowed)) ||
- (!cpumask_empty(&off_cpus) && !cpumask_empty(cs->cpus_allowed)))
- update_tasks_cpumask(cs);
+ cpumask_and(&new_cpus, cs->cpus_allowed, parent_cs(cs)->effective_cpus);
+ nodes_and(new_mems, cs->mems_allowed, parent_cs(cs)->effective_mems);
- mutex_lock(&callback_mutex);
- nodes_andnot(cs->mems_allowed, cs->mems_allowed, off_mems);
- mutex_unlock(&callback_mutex);
-
- /*
- * If sane_behavior flag is set, we need to update tasks' nodemask
- * for empty cpuset to take on ancestor's nodemask. Otherwise, don't
- * call update_tasks_nodemask() if the cpuset becomes empty, as
- * the tasks in it will be migratd to an ancestor.
- */
- if ((sane && nodes_empty(cs->mems_allowed)) ||
- (!nodes_empty(off_mems) && !nodes_empty(cs->mems_allowed)))
- update_tasks_nodemask(cs);
+ cpus_updated = !cpumask_equal(&new_cpus, cs->effective_cpus);
+ mems_updated = !nodes_equal(new_mems, cs->effective_mems);
- is_empty = cpumask_empty(cs->cpus_allowed) ||
- nodes_empty(cs->mems_allowed);
+ if (cgroup_on_dfl(cs->css.cgroup))
+ hotplug_update_tasks(cs, &new_cpus, &new_mems,
+ cpus_updated, mems_updated);
+ else
+ hotplug_update_tasks_legacy(cs, &new_cpus, &new_mems,
+ cpus_updated, mems_updated);
mutex_unlock(&cpuset_mutex);
-
- /*
- * If sane_behavior flag is set, we'll keep tasks in empty cpusets.
- *
- * Otherwise move tasks to the nearest ancestor with execution
- * resources. This is full cgroup operation which will
- * also call back into cpuset. Should be done outside any lock.
- */
- if (!sane && is_empty)
- remove_tasks_in_empty_cpuset(cs);
}
/**
@@ -2132,6 +2244,7 @@ static void cpuset_hotplug_workfn(struct work_struct *work)
static cpumask_t new_cpus;
static nodemask_t new_mems;
bool cpus_updated, mems_updated;
+ bool on_dfl = cgroup_on_dfl(top_cpuset.css.cgroup);
mutex_lock(&cpuset_mutex);
@@ -2139,13 +2252,15 @@ static void cpuset_hotplug_workfn(struct work_struct *work)
cpumask_copy(&new_cpus, cpu_active_mask);
new_mems = node_states[N_MEMORY];
- cpus_updated = !cpumask_equal(top_cpuset.cpus_allowed, &new_cpus);
- mems_updated = !nodes_equal(top_cpuset.mems_allowed, new_mems);
+ cpus_updated = !cpumask_equal(top_cpuset.effective_cpus, &new_cpus);
+ mems_updated = !nodes_equal(top_cpuset.effective_mems, new_mems);
/* synchronize cpus_allowed to cpu_active_mask */
if (cpus_updated) {
mutex_lock(&callback_mutex);
- cpumask_copy(top_cpuset.cpus_allowed, &new_cpus);
+ if (!on_dfl)
+ cpumask_copy(top_cpuset.cpus_allowed, &new_cpus);
+ cpumask_copy(top_cpuset.effective_cpus, &new_cpus);
mutex_unlock(&callback_mutex);
/* we don't mess with cpumasks of tasks in top_cpuset */
}
@@ -2153,7 +2268,9 @@ static void cpuset_hotplug_workfn(struct work_struct *work)
/* synchronize mems_allowed to N_MEMORY */
if (mems_updated) {
mutex_lock(&callback_mutex);
- top_cpuset.mems_allowed = new_mems;
+ if (!on_dfl)
+ top_cpuset.mems_allowed = new_mems;
+ top_cpuset.effective_mems = new_mems;
mutex_unlock(&callback_mutex);
update_tasks_nodemask(&top_cpuset);
}
@@ -2228,6 +2345,9 @@ void __init cpuset_init_smp(void)
top_cpuset.mems_allowed = node_states[N_MEMORY];
top_cpuset.old_mems_allowed = top_cpuset.mems_allowed;
+ cpumask_copy(top_cpuset.effective_cpus, cpu_active_mask);
+ top_cpuset.effective_mems = node_states[N_MEMORY];
+
register_hotmemory_notifier(&cpuset_track_online_nodes_nb);
}
@@ -2244,23 +2364,17 @@ void __init cpuset_init_smp(void)
void cpuset_cpus_allowed(struct task_struct *tsk, struct cpumask *pmask)
{
- struct cpuset *cpus_cs;
-
mutex_lock(&callback_mutex);
rcu_read_lock();
- cpus_cs = effective_cpumask_cpuset(task_cs(tsk));
- guarantee_online_cpus(cpus_cs, pmask);
+ guarantee_online_cpus(task_cs(tsk), pmask);
rcu_read_unlock();
mutex_unlock(&callback_mutex);
}
void cpuset_cpus_allowed_fallback(struct task_struct *tsk)
{
- struct cpuset *cpus_cs;
-
rcu_read_lock();
- cpus_cs = effective_cpumask_cpuset(task_cs(tsk));
- do_set_cpus_allowed(tsk, cpus_cs->cpus_allowed);
+ do_set_cpus_allowed(tsk, task_cs(tsk)->effective_cpus);
rcu_read_unlock();
/*
@@ -2299,13 +2413,11 @@ void cpuset_init_current_mems_allowed(void)
nodemask_t cpuset_mems_allowed(struct task_struct *tsk)
{
- struct cpuset *mems_cs;
nodemask_t mask;
mutex_lock(&callback_mutex);
rcu_read_lock();
- mems_cs = effective_nodemask_cpuset(task_cs(tsk));
- guarantee_online_mems(mems_cs, &mask);
+ guarantee_online_mems(task_cs(tsk), &mask);
rcu_read_unlock();
mutex_unlock(&callback_mutex);
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index bc1638b33449..126f7e3f04e7 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -8083,7 +8083,7 @@ struct cgroup_subsys cpu_cgrp_subsys = {
.can_attach = cpu_cgroup_can_attach,
.attach = cpu_cgroup_attach,
.exit = cpu_cgroup_exit,
- .base_cftypes = cpu_files,
+ .legacy_cftypes = cpu_files,
.early_init = 1,
};
diff --git a/kernel/sched/cpuacct.c b/kernel/sched/cpuacct.c
index 9cf350c94ec4..dd7cbb55bbf2 100644
--- a/kernel/sched/cpuacct.c
+++ b/kernel/sched/cpuacct.c
@@ -278,6 +278,6 @@ void cpuacct_account_field(struct task_struct *p, int index, u64 val)
struct cgroup_subsys cpuacct_cgrp_subsys = {
.css_alloc = cpuacct_css_alloc,
.css_free = cpuacct_css_free,
- .base_cftypes = files,
+ .legacy_cftypes = files,
.early_init = 1,
};
diff --git a/mm/hugetlb_cgroup.c b/mm/hugetlb_cgroup.c
index 493f758445e7..9aae6f47433f 100644
--- a/mm/hugetlb_cgroup.c
+++ b/mm/hugetlb_cgroup.c
@@ -358,9 +358,8 @@ static void __init __hugetlb_cgroup_file_init(int idx)
cft = &h->cgroup_files[4];
memset(cft, 0, sizeof(*cft));
- WARN_ON(cgroup_add_cftypes(&hugetlb_cgrp_subsys, h->cgroup_files));
-
- return;
+ WARN_ON(cgroup_add_legacy_cftypes(&hugetlb_cgrp_subsys,
+ h->cgroup_files));
}
void __init hugetlb_cgroup_file_init(void)
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 1f14a430c656..f009a14918d2 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -6007,7 +6007,6 @@ static struct cftype mem_cgroup_files[] = {
},
{
.name = "use_hierarchy",
- .flags = CFTYPE_INSANE,
.write_u64 = mem_cgroup_hierarchy_write,
.read_u64 = mem_cgroup_hierarchy_read,
},
@@ -6411,6 +6410,29 @@ static void mem_cgroup_css_free(struct cgroup_subsys_state *css)
__mem_cgroup_free(memcg);
}
+/**
+ * mem_cgroup_css_reset - reset the states of a mem_cgroup
+ * @css: the target css
+ *
+ * Reset the states of the mem_cgroup associated with @css. This is
+ * invoked when the userland requests disabling on the default hierarchy
+ * but the memcg is pinned through dependency. The memcg should stop
+ * applying policies and should revert to the vanilla state as it may be
+ * made visible again.
+ *
+ * The current implementation only resets the essential configurations.
+ * This needs to be expanded to cover all the visible parts.
+ */
+static void mem_cgroup_css_reset(struct cgroup_subsys_state *css)
+{
+ struct mem_cgroup *memcg = mem_cgroup_from_css(css);
+
+ mem_cgroup_resize_limit(memcg, ULLONG_MAX);
+ mem_cgroup_resize_memsw_limit(memcg, ULLONG_MAX);
+ memcg_update_kmem_limit(memcg, ULLONG_MAX);
+ res_counter_set_soft_limit(&memcg->res, ULLONG_MAX);
+}
+
#ifdef CONFIG_MMU
/* Handlers for move charge at task migration. */
#define PRECHARGE_COUNT_AT_ONCE 256
@@ -7005,16 +7027,17 @@ static void mem_cgroup_move_task(struct cgroup_subsys_state *css,
/*
* Cgroup retains root cgroups across [un]mount cycles making it necessary
- * to verify sane_behavior flag on each mount attempt.
+ * to verify whether we're attached to the default hierarchy on each mount
+ * attempt.
*/
static void mem_cgroup_bind(struct cgroup_subsys_state *root_css)
{
/*
- * use_hierarchy is forced with sane_behavior. cgroup core
+ * use_hierarchy is forced on the default hierarchy. cgroup core
* guarantees that @root doesn't have any children, so turning it
* on for the root memcg is enough.
*/
- if (cgroup_sane_behavior(root_css->cgroup))
+ if (cgroup_on_dfl(root_css->cgroup))
mem_cgroup_from_css(root_css)->use_hierarchy = true;
}
@@ -7023,11 +7046,12 @@ struct cgroup_subsys memory_cgrp_subsys = {
.css_online = mem_cgroup_css_online,
.css_offline = mem_cgroup_css_offline,
.css_free = mem_cgroup_css_free,
+ .css_reset = mem_cgroup_css_reset,
.can_attach = mem_cgroup_can_attach,
.cancel_attach = mem_cgroup_cancel_attach,
.attach = mem_cgroup_move_task,
.bind = mem_cgroup_bind,
- .base_cftypes = mem_cgroup_files,
+ .legacy_cftypes = mem_cgroup_files,
.early_init = 0,
};
@@ -7044,7 +7068,8 @@ __setup("swapaccount=", enable_swap_account);
static void __init memsw_file_init(void)
{
- WARN_ON(cgroup_add_cftypes(&memory_cgrp_subsys, memsw_cgroup_files));
+ WARN_ON(cgroup_add_legacy_cftypes(&memory_cgrp_subsys,
+ memsw_cgroup_files));
}
static void __init enable_swap_cgroup(void)
diff --git a/net/core/netclassid_cgroup.c b/net/core/netclassid_cgroup.c
index 30d903b19c62..1f2a126f4ffa 100644
--- a/net/core/netclassid_cgroup.c
+++ b/net/core/netclassid_cgroup.c
@@ -107,5 +107,5 @@ struct cgroup_subsys net_cls_cgrp_subsys = {
.css_online = cgrp_css_online,
.css_free = cgrp_css_free,
.attach = cgrp_attach,
- .base_cftypes = ss_files,
+ .legacy_cftypes = ss_files,
};
diff --git a/net/core/netprio_cgroup.c b/net/core/netprio_cgroup.c
index 2f385b9bccc0..cbd0a199bf52 100644
--- a/net/core/netprio_cgroup.c
+++ b/net/core/netprio_cgroup.c
@@ -249,7 +249,7 @@ struct cgroup_subsys net_prio_cgrp_subsys = {
.css_online = cgrp_css_online,
.css_free = cgrp_css_free,
.attach = net_prio_attach,
- .base_cftypes = ss_files,
+ .legacy_cftypes = ss_files,
};
static int netprio_device_event(struct notifier_block *unused,
diff --git a/net/ipv4/tcp_memcontrol.c b/net/ipv4/tcp_memcontrol.c
index f7a2ec3ac584..3af522622fad 100644
--- a/net/ipv4/tcp_memcontrol.c
+++ b/net/ipv4/tcp_memcontrol.c
@@ -222,7 +222,7 @@ static struct cftype tcp_files[] = {
static int __init tcp_memcontrol_init(void)
{
- WARN_ON(cgroup_add_cftypes(&memory_cgrp_subsys, tcp_files));
+ WARN_ON(cgroup_add_legacy_cftypes(&memory_cgrp_subsys, tcp_files));
return 0;
}
__initcall(tcp_memcontrol_init);
diff --git a/security/device_cgroup.c b/security/device_cgroup.c
index d9d69e6930ed..188c1d26393b 100644
--- a/security/device_cgroup.c
+++ b/security/device_cgroup.c
@@ -796,7 +796,7 @@ struct cgroup_subsys devices_cgrp_subsys = {
.css_free = devcgroup_css_free,
.css_online = devcgroup_online,
.css_offline = devcgroup_offline,
- .base_cftypes = dev_cgroup_files,
+ .legacy_cftypes = dev_cgroup_files,
};
/**
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-18 18:21:41 +0100