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(I'm so sorry!) Linux kernel mirror (for testing) git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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#include <linux/limits.h>#include <linux/list.h>#include <linux/idr.h>#include <linux/wait.h>#include <linux/mutex.h>#include <linux/rcupdate.h>#include <linux/refcount.h>#include <linux/percpu-refcount.h>#include <linux/percpu-rwsem.h>#include <linux/sched.h>#include <linux/u64_stats_sync.h>#include <linux/workqueue.h>#include <linux/bpf-cgroup-defs.h>#include <linux/psi_types.h>
#ifdef CONFIG_CGROUPS
struct cgroup;struct cgroup_root;struct cgroup_subsys;struct cgroup_taskset;struct kernfs_node;struct kernfs_ops;struct kernfs_open_file;struct seq_file;struct poll_table_struct;
#define MAX_CGROUP_TYPE_NAMELEN 32#define MAX_CGROUP_ROOT_NAMELEN 64#define MAX_CFTYPE_NAME 64
/* define the enumeration of all cgroup subsystems */#define SUBSYS(_x) _x ## _cgrp_id,enum cgroup_subsys_id {#include <linux/cgroup_subsys.h> CGROUP_SUBSYS_COUNT,};#undef SUBSYS
/* bits in struct cgroup_subsys_state flags field */enum { CSS_NO_REF = (1 << 0), /* no reference counting for this css */ CSS_ONLINE = (1 << 1), /* between ->css_online() and ->css_offline() */ CSS_RELEASED = (1 << 2), /* refcnt reached zero, released */ CSS_VISIBLE = (1 << 3), /* css is visible to userland */ CSS_DYING = (1 << 4), /* css is dying */};
/* bits in struct cgroup flags field */enum { /* Control Group requires release notifications to userspace */ CGRP_NOTIFY_ON_RELEASE, /* * Clone the parent's configuration when creating a new child * cpuset cgroup. For historical reasons, this option can be * specified at mount time and thus is implemented here. */ CGRP_CPUSET_CLONE_CHILDREN,
/* Control group has to be frozen. */ CGRP_FREEZE,
/* Cgroup is frozen. */ CGRP_FROZEN,};
/* cgroup_root->flags */enum { CGRP_ROOT_NOPREFIX = (1 << 1), /* mounted subsystems have no named prefix */ CGRP_ROOT_XATTR = (1 << 2), /* supports extended attributes */
/* * Consider namespaces as delegation boundaries. If this flag is * set, controller specific interface files in a namespace root * aren't writeable from inside the namespace. */ CGRP_ROOT_NS_DELEGATE = (1 << 3),
/* * Reduce latencies on dynamic cgroup modifications such as task * migrations and controller on/offs by disabling percpu operation on * cgroup_threadgroup_rwsem. This makes hot path operations such as * forks and exits into the slow path and more expensive. * * Alleviate the contention between fork, exec, exit operations and * writing to cgroup.procs by taking a per threadgroup rwsem instead of * the global cgroup_threadgroup_rwsem. Fork and other operations * from threads in different thread groups no longer contend with * writing to cgroup.procs. * * The static usage pattern of creating a cgroup, enabling controllers, * and then seeding it with CLONE_INTO_CGROUP doesn't require write * locking cgroup_threadgroup_rwsem and thus doesn't benefit from * favordynmod. */ CGRP_ROOT_FAVOR_DYNMODS = (1 << 4),
/* * Enable cpuset controller in v1 cgroup to use v2 behavior. */ CGRP_ROOT_CPUSET_V2_MODE = (1 << 16),
/* * Enable legacy local memory.events. */ CGRP_ROOT_MEMORY_LOCAL_EVENTS = (1 << 17),
/* * Enable recursive subtree protection */ CGRP_ROOT_MEMORY_RECURSIVE_PROT = (1 << 18),
/* * Enable hugetlb accounting for the memory controller. */ CGRP_ROOT_MEMORY_HUGETLB_ACCOUNTING = (1 << 19),
/* * Enable legacy local pids.events. */ CGRP_ROOT_PIDS_LOCAL_EVENTS = (1 << 20),};
/* cftype->flags */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_NS_DELEGATABLE = (1 << 2), /* writeable beyond delegation boundaries */
CFTYPE_NO_PREFIX = (1 << 3), /* (DON'T USE FOR NEW FILES) no subsys prefix */ CFTYPE_WORLD_WRITABLE = (1 << 4), /* (DON'T USE FOR NEW FILES) S_IWUGO */ CFTYPE_DEBUG = (1 << 5), /* create when cgroup_debug */
/* 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 */ __CFTYPE_ADDED = (1 << 18),};
enum cgroup_attach_lock_mode { /* Default */ CGRP_ATTACH_LOCK_GLOBAL,
/* When pid=0 && threadgroup=false, see comments in cgroup_procs_write_start */ CGRP_ATTACH_LOCK_NONE,
/* When favordynmods is on, see comments above CGRP_ROOT_FAVOR_DYNMODS */ CGRP_ATTACH_LOCK_PER_THREADGROUP,};
/* * cgroup_file is the handle for a file instance created in a cgroup which * is used, for example, to generate file changed notifications. This can * be obtained by setting cftype->file_offset. */struct cgroup_file { /* do not access any fields from outside cgroup core */ struct kernfs_node *kn; unsigned long notified_at; struct timer_list notify_timer; spinlock_t lock;};
/* * Per-subsystem/per-cgroup state maintained by the system. This is the * fundamental structural building block that controllers deal with. * * Fields marked with "PI:" are public and immutable and may be accessed * directly without synchronization. */struct cgroup_subsys_state { /* PI: the cgroup that this css is attached to */ struct cgroup *cgroup;
/* PI: the cgroup subsystem that this css is attached to */ struct cgroup_subsys *ss;
/* reference count - access via css_[try]get() and css_put() */ struct percpu_ref refcnt;
/* * Depending on the context, this field is initialized * via css_rstat_init() at different places: * * when css is associated with cgroup::self * when css->cgroup is the root cgroup * performed in cgroup_init() * when css->cgroup is not the root cgroup * performed in cgroup_create() * when css is associated with a subsystem * when css->cgroup is the root cgroup * performed in cgroup_init_subsys() in the non-early path * when css->cgroup is not the root cgroup * performed in css_create() */ struct css_rstat_cpu __percpu *rstat_cpu;
/* * siblings list anchored at the parent's ->children * * linkage is protected by cgroup_mutex or RCU */ struct list_head sibling; struct list_head children;
/* * PI: Subsys-unique ID. 0 is unused and root is always 1. The * matching css can be looked up using css_from_id(). */ int id;
unsigned int flags;
/* * Monotonically increasing unique serial number which defines a * uniform order among all csses. It's guaranteed that all * ->children lists are in the ascending order of ->serial_nr and * used to allow interrupting and resuming iterations. */ u64 serial_nr;
/* * Incremented by online self and children. Used to guarantee that * parents are not offlined before their children. */ atomic_t online_cnt;
/* percpu_ref killing and RCU release */ struct work_struct destroy_work; struct rcu_work destroy_rwork;
/* * PI: the parent css. Placed here for cache proximity to following * fields of the containing structure. */ struct cgroup_subsys_state *parent;
/* * Keep track of total numbers of visible descendant CSSes. * The total number of dying CSSes is tracked in * css->cgroup->nr_dying_subsys[ssid]. * Protected by cgroup_mutex. */ int nr_descendants;
/* * Hierarchical populated state. For cgroup->self, nr_populated_csets * counts populated csets linked via cgrp_cset_link. * nr_populated_children counts immediate-child csses whose own * populated state is nonzero. Protected by css_set_lock. */ int nr_populated_csets; int nr_populated_children;
/* deferred kill_css_finish() queued by css_update_populated() */ struct work_struct kill_finish_work;
/* * A singly-linked list of css structures to be rstat flushed. * This is a scratch field to be used exclusively by * css_rstat_flush(). * * Protected by rstat_base_lock when css is cgroup::self. * Protected by css->ss->rstat_ss_lock otherwise. */ struct cgroup_subsys_state *rstat_flush_next;};
/* * A css_set is a structure holding pointers to a set of * cgroup_subsys_state objects. This saves space in the task struct * object and speeds up fork()/exit(), since a single inc/dec and a * list_add()/del() can bump the reference count on the entire cgroup * set for a task. */struct css_set { /* * Set of subsystem states, one for each subsystem. This array is * immutable after creation apart from the init_css_set during * subsystem registration (at boot time). */ struct cgroup_subsys_state *subsys[CGROUP_SUBSYS_COUNT];
/* reference count */ refcount_t refcount;
/* * For a domain cgroup, the following points to self. If threaded, * to the matching cset of the nearest domain ancestor. The * dom_cset provides access to the domain cgroup and its csses to * which domain level resource consumptions should be charged. */ struct css_set *dom_cset;
/* the default cgroup associated with this css_set */ struct cgroup *dfl_cgrp;
/* internal task count, protected by css_set_lock */ int nr_tasks;
/* * Lists running through all tasks using this cgroup group. * mg_tasks lists tasks which belong to this cset but are in the * process of being migrated out or in. Protected by * css_set_lock, but, during migration, once tasks are moved to * mg_tasks, it can be read safely while holding cgroup_mutex. */ struct list_head tasks; struct list_head mg_tasks; struct list_head dying_tasks;
/* all css_task_iters currently walking this cset */ struct list_head task_iters;
/* * On the default hierarchy, ->subsys[ssid] may point to a css * attached to an ancestor instead of the cgroup this css_set is * associated with. The following node is anchored at * ->subsys[ssid]->cgroup->e_csets[ssid] and provides a way to * iterate through all css's attached to a given cgroup. */ struct list_head e_cset_node[CGROUP_SUBSYS_COUNT];
/* all threaded csets whose ->dom_cset points to this cset */ struct list_head threaded_csets; struct list_head threaded_csets_node;
/* * List running through all cgroup groups in the same hash * slot. Protected by css_set_lock */ struct hlist_node hlist;
/* * List of cgrp_cset_links pointing at cgroups referenced from this * css_set. Protected by css_set_lock. */ struct list_head cgrp_links;
/* * List of csets participating in the on-going migration either as * source or destination. Protected by cgroup_mutex. */ struct list_head mg_src_preload_node; struct list_head mg_dst_preload_node; struct list_head mg_node;
/* * If this cset is acting as the source of migration the following * two fields are set. mg_src_cgrp and mg_dst_cgrp are * respectively the source and destination cgroups of the on-going * migration. mg_dst_cset is the destination cset the target tasks * on this cset should be migrated to. Protected by cgroup_mutex. */ struct cgroup *mg_src_cgrp; struct cgroup *mg_dst_cgrp; struct css_set *mg_dst_cset;
/* dead and being drained, ignore for migration */ bool dead;
/* For RCU-protected deletion */ struct rcu_head rcu_head;};
struct cgroup_base_stat { struct task_cputime cputime;
#ifdef CONFIG_SCHED_CORE u64 forceidle_sum;#endif u64 ntime;};
/* * rstat - cgroup scalable recursive statistics. Accounting is done * per-cpu in css_rstat_cpu which is then lazily propagated up the * hierarchy on reads. * * When a stat gets updated, the css_rstat_cpu and its ancestors are * linked into the updated tree. On the following read, propagation only * considers and consumes the updated tree. This makes reading O(the * number of descendants which have been active since last read) instead of * O(the total number of descendants). * * This is important because there can be a lot of (draining) cgroups which * aren't active and stat may be read frequently. The combination can * become very expensive. By propagating selectively, increasing reading * frequency decreases the cost of each read. * * This struct hosts both the fields which implement the above - * updated_children and updated_next. */struct css_rstat_cpu { /* * Child cgroups with stat updates on this cpu since the last read * are linked on the parent's ->updated_children through * ->updated_next. updated_children is terminated by its container css. */ struct cgroup_subsys_state *updated_children; struct cgroup_subsys_state *updated_next; /* NULL if not on the list */
struct llist_node lnode; /* lockless list for update */ struct cgroup_subsys_state *owner; /* back pointer */};
/* * This struct hosts the fields which track basic resource statistics on * top of it - bsync, bstat and last_bstat. */struct cgroup_rstat_base_cpu { /* * ->bsync protects ->bstat. These are the only fields which get * updated in the hot path. */ struct u64_stats_sync bsync; struct cgroup_base_stat bstat;
/* * Snapshots at the last reading. These are used to calculate the * deltas to propagate to the global counters. */ struct cgroup_base_stat last_bstat;
/* * This field is used to record the cumulative per-cpu time of * the cgroup and its descendants. Currently it can be read via * eBPF/drgn etc, and we are still trying to determine how to * expose it in the cgroupfs interface. */ struct cgroup_base_stat subtree_bstat;
/* * Snapshots at the last reading. These are used to calculate the * deltas to propagate to the per-cpu subtree_bstat. */ struct cgroup_base_stat last_subtree_bstat;};
struct cgroup_freezer_state { /* Should the cgroup and its descendants be frozen. */ bool freeze;
/* Should the cgroup actually be frozen? */ bool e_freeze;
/* Fields below are protected by css_set_lock */
/* Number of frozen descendant cgroups */ int nr_frozen_descendants;
/* * Number of tasks, which are counted as frozen: * frozen, SIGSTOPped, and PTRACEd. */ int nr_frozen_tasks;
/* Freeze time data consistency protection */ seqcount_spinlock_t freeze_seq;
/* * Most recent time the cgroup was requested to freeze. * Accesses guarded by freeze_seq counter. Writes serialized * by css_set_lock. */ u64 freeze_start_nsec;
/* * Total duration the cgroup has spent freezing. * Accesses guarded by freeze_seq counter. Writes serialized * by css_set_lock. */ u64 frozen_nsec;};
struct cgroup { /* self css with NULL ->ss, points back to this cgroup */ struct cgroup_subsys_state self;
unsigned long flags; /* "unsigned long" so bitops work */
/* * The depth this cgroup is at. The root is at depth zero and each * step down the hierarchy increments the level. This along with * ancestors[] can determine whether a given cgroup is a * descendant of another without traversing the hierarchy. */ int level;
/* Maximum allowed descent tree depth */ int max_depth;
/* * Keep track of total numbers of visible and dying descent cgroups. * Dying cgroups are cgroups which were deleted by a user, * but are still existing because someone else is holding a reference. * max_descendants is a maximum allowed number of descent cgroups. * * nr_descendants and nr_dying_descendants are protected * by cgroup_mutex and css_set_lock. It's fine to read them holding * any of cgroup_mutex and css_set_lock; for writing both locks * should be held. */ int nr_descendants; int nr_dying_descendants; int max_descendants;
/* * Domain/threaded split of self.nr_populated_children: each counts * immediate-child cgroups whose subtree is populated and sums to * self.nr_populated_children. Kept as separate fields to allow readers * like cgroup_can_be_thread_root() unlocked access. Protected by * css_set_lock; updated by css_update_populated(). */ int nr_populated_domain_children; int nr_populated_threaded_children;
int nr_threaded_children; /* # of live threaded child cgroups */
/* * Sequence number for cgroup.kill. Incremented with both cgroup_mutex * and css_set_lock held. Readers hold either one. */ unsigned int kill_seq;
struct kernfs_node *kn; /* cgroup kernfs entry */ struct cgroup_file procs_file; /* handle for "cgroup.procs" */ struct cgroup_file events_file; /* handle for "cgroup.events" */
/* handles for "{cpu,memory,io,irq}.pressure" */ struct cgroup_file psi_files[NR_PSI_RESOURCES];
/* * The bitmask of subsystems enabled on the child cgroups. * ->subtree_control is the one configured through * "cgroup.subtree_control" while ->subtree_ss_mask is the effective * one which may have more subsystems enabled. Controller knobs * are made available iff it's enabled in ->subtree_control. */ u32 subtree_control; u32 subtree_ss_mask; u32 old_subtree_control; u32 old_subtree_ss_mask;
/* Private pointers for each registered subsystem */ struct cgroup_subsys_state __rcu *subsys[CGROUP_SUBSYS_COUNT];
/* * Effective css for each subsystem: the css of the nearest ancestor, * including this cgroup, that has the subsystem enabled, or the root * css if the subsystem isn't bound to this hierarchy. Updated under * cgroup_mutex and read under RCU. */ struct cgroup_subsys_state __rcu *e_css[CGROUP_SUBSYS_COUNT];
/* * Keep track of total number of dying CSSes at and below this cgroup. * Protected by cgroup_mutex. */ int nr_dying_subsys[CGROUP_SUBSYS_COUNT];
struct cgroup_root *root;
/* * List of cgrp_cset_links pointing at css_sets with tasks in this * cgroup. Protected by css_set_lock. */ struct list_head cset_links;
/* * On the default hierarchy, a css_set for a cgroup with some * susbsys disabled will point to css's which are associated with * the closest ancestor which has the subsys enabled. The * following lists all css_sets which point to this cgroup's css * for the given subsystem. */ struct list_head e_csets[CGROUP_SUBSYS_COUNT];
/* * If !threaded, self. If threaded, it points to the nearest * domain ancestor. Inside a threaded subtree, cgroups are exempt * from process granularity and no-internal-task constraint. * Domain level resource consumptions which aren't tied to a * specific task are charged to the dom_cgrp. */ struct cgroup *dom_cgrp; struct cgroup *old_dom_cgrp; /* used while enabling threaded */
/* * Depending on the context, this field is initialized via * css_rstat_init() at different places: * * when cgroup is the root cgroup * performed in cgroup_setup_root() * otherwise * performed in cgroup_create() */ struct cgroup_rstat_base_cpu __percpu *rstat_base_cpu;
/* * Add padding to keep the read mostly rstat per-cpu pointer on a * different cacheline than the following *bstat fields which can have * frequent updates. */ CACHELINE_PADDING(_pad_);
/* cgroup basic resource statistics */ struct cgroup_base_stat last_bstat; struct cgroup_base_stat bstat; struct prev_cputime prev_cputime; /* for printing out cputime */
/* * list of pidlists, up to two for each namespace (one for procs, one * for tasks); created on demand. */ struct list_head pidlists; struct mutex pidlist_mutex;
/* used to wait for offlining of csses */ wait_queue_head_t offline_waitq;
/* used to schedule release agent */ struct work_struct release_agent_work;
/* used to track pressure stalls */ struct psi_group *psi;
/* used to store eBPF programs */ struct cgroup_bpf bpf;
/* Used to store internal freezer state */ struct cgroup_freezer_state freezer;
#ifdef CONFIG_BPF_SYSCALL struct bpf_local_storage __rcu *bpf_cgrp_storage;#endif#ifdef CONFIG_EXT_SUB_SCHED struct scx_sched __rcu *scx_sched;#endif
/* All ancestors including self */ union { DECLARE_FLEX_ARRAY(struct cgroup *, ancestors); struct { struct cgroup *_root_ancestor; DECLARE_FLEX_ARRAY(struct cgroup *, _low_ancestors); }; };};
/* * A cgroup_root represents the root of a cgroup hierarchy, and may be * associated with a kernfs_root to form an active hierarchy. This is * internal to cgroup core. Don't access directly from controllers. */struct cgroup_root { struct kernfs_root *kf_root;
/* The bitmask of subsystems attached to this hierarchy */ unsigned int subsys_mask;
/* Unique id for this hierarchy. */ int hierarchy_id;
/* A list running through the active hierarchies */ struct list_head root_list; struct rcu_head rcu; /* Must be near the top */
/* Number of cgroups in the hierarchy, used only for /proc/cgroups */ atomic_t nr_cgrps;
/* Hierarchy-specific flags */ unsigned int flags;
/* The path to use for release notifications. */ char release_agent_path[PATH_MAX];
/* The name for this hierarchy - may be empty */ char name[MAX_CGROUP_ROOT_NAMELEN];
/* * The root cgroup. The containing cgroup_root will be destroyed on its * release. This must be embedded last due to flexible array at the end * of struct cgroup. */ struct cgroup cgrp;};
/* * struct cftype: handler definitions for cgroup control files * * When reading/writing to a file: * - the cgroup to use is file->f_path.dentry->d_parent->d_fsdata * - the 'cftype' of the file is file->f_path.dentry->d_fsdata */struct cftype { /* * Name of the subsystem is prepended in cgroup_file_name(). * Zero length string indicates end of cftype array. */ char name[MAX_CFTYPE_NAME]; unsigned long private;
/* * The maximum length of string, excluding trailing nul, that can * be passed to write. If < PAGE_SIZE-1, PAGE_SIZE-1 is assumed. */ size_t max_write_len;
/* CFTYPE_* flags */ unsigned int flags;
/* * If non-zero, should contain the offset from the start of css to * a struct cgroup_file field. cgroup will record the handle of * the created file into it. The recorded handle can be used as * long as the containing css remains accessible. */ unsigned int file_offset;
/* * Fields used for internal bookkeeping. Initialized automatically * during registration. */ struct cgroup_subsys *ss; /* NULL for cgroup core files */ struct list_head node; /* anchored at ss->cfts */ struct kernfs_ops *kf_ops;
int (*open)(struct kernfs_open_file *of); void (*release)(struct kernfs_open_file *of);
/* * read_u64() is a shortcut for the common case of returning a * single integer. Use it in place of read() */ u64 (*read_u64)(struct cgroup_subsys_state *css, struct cftype *cft); /* * read_s64() is a signed version of read_u64() */ s64 (*read_s64)(struct cgroup_subsys_state *css, struct cftype *cft);
/* generic seq_file read interface */ int (*seq_show)(struct seq_file *sf, void *v);
/* optional ops, implement all or none */ void *(*seq_start)(struct seq_file *sf, loff_t *ppos); void *(*seq_next)(struct seq_file *sf, void *v, loff_t *ppos); void (*seq_stop)(struct seq_file *sf, void *v);
/* * write_u64() is a shortcut for the common case of accepting * a single integer (as parsed by simple_strtoull) from * userspace. Use in place of write(); return 0 or error. */ int (*write_u64)(struct cgroup_subsys_state *css, struct cftype *cft, u64 val); /* * write_s64() is a signed version of write_u64() */ int (*write_s64)(struct cgroup_subsys_state *css, struct cftype *cft, s64 val);
/* * write() is the generic write callback which maps directly to * kernfs write operation and overrides all other operations. * Maximum write size is determined by ->max_write_len. Use * of_css/cft() to access the associated css and cft. */ ssize_t (*write)(struct kernfs_open_file *of, char *buf, size_t nbytes, loff_t off);
__poll_t (*poll)(struct kernfs_open_file *of, struct poll_table_struct *pt);
struct lock_class_key lockdep_key;};
/* * Control Group subsystem type. * See Documentation/admin-guide/cgroup-v1/cgroups.rst for details */struct cgroup_subsys { struct cgroup_subsys_state *(*css_alloc)(struct cgroup_subsys_state *parent_css); int (*css_online)(struct cgroup_subsys_state *css); void (*css_offline)(struct cgroup_subsys_state *css); void (*css_released)(struct cgroup_subsys_state *css); void (*css_free)(struct cgroup_subsys_state *css); void (*css_reset)(struct cgroup_subsys_state *css); void (*css_killed)(struct cgroup_subsys_state *css); void (*css_rstat_flush)(struct cgroup_subsys_state *css, int cpu); int (*css_extra_stat_show)(struct seq_file *seq, struct cgroup_subsys_state *css); int (*css_local_stat_show)(struct seq_file *seq, struct cgroup_subsys_state *css);
int (*can_attach)(struct cgroup_taskset *tset); void (*cancel_attach)(struct cgroup_taskset *tset); void (*attach)(struct cgroup_taskset *tset); int (*can_fork)(struct task_struct *task, struct css_set *cset); void (*cancel_fork)(struct task_struct *task, struct css_set *cset); void (*fork)(struct task_struct *task); void (*exit)(struct task_struct *task); void (*release)(struct task_struct *task); void (*bind)(struct cgroup_subsys_state *root_css);
bool early_init:1;
/* * If %true, the controller, on the default hierarchy, doesn't show * up in "cgroup.controllers" or "cgroup.subtree_control", is * implicitly enabled on all cgroups on the default hierarchy, and * bypasses the "no internal process" constraint. This is for * utility type controllers which is transparent to userland. * * An implicit controller can be stolen from the default hierarchy * anytime and thus must be okay with offline csses from previous * hierarchies coexisting with csses for the current one. */ bool implicit_on_dfl:1;
/* * If %true, the controller, supports threaded mode on the default * hierarchy. In a threaded subtree, both process granularity and * no-internal-process constraint are ignored and a threaded * controllers should be able to handle that. * * Note that as an implicit controller is automatically enabled on * all cgroups on the default hierarchy, it should also be * threaded. implicit && !threaded is not supported. */ bool threaded:1;
/* the following two fields are initialized automatically during boot */ int id; const char *name;
/* optional, initialized automatically during boot if not set */ const char *legacy_name;
/* link to parent, protected by cgroup_lock() */ struct cgroup_root *root;
/* idr for css->id */ struct idr css_idr;
/* * List of cftypes. Each entry is the first entry of an array * terminated by zero length name. */ struct list_head cfts;
/* * 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;
spinlock_t rstat_ss_lock; struct llist_head __percpu *lhead; /* lockless update list head */};
extern struct percpu_rw_semaphore cgroup_threadgroup_rwsem;extern bool cgroup_enable_per_threadgroup_rwsem;
struct cgroup_of_peak { unsigned long value; struct list_head list;};
/** * cgroup_threadgroup_change_begin - threadgroup exclusion for cgroups * @tsk: target task * * Allows cgroup operations to synchronize against threadgroup changes * using a global percpu_rw_semaphore and a per threadgroup rw_semaphore when * favordynmods is on. See the comment above CGRP_ROOT_FAVOR_DYNMODS definition. */static inline void cgroup_threadgroup_change_begin(struct task_struct *tsk){ percpu_down_read(&cgroup_threadgroup_rwsem); if (cgroup_enable_per_threadgroup_rwsem) down_read(&tsk->signal->cgroup_threadgroup_rwsem);}
/** * cgroup_threadgroup_change_end - threadgroup exclusion for cgroups * @tsk: target task * * Counterpart of cgroup_threadgroup_change_begin(). */static inline void cgroup_threadgroup_change_end(struct task_struct *tsk){ if (cgroup_enable_per_threadgroup_rwsem) up_read(&tsk->signal->cgroup_threadgroup_rwsem); percpu_up_read(&cgroup_threadgroup_rwsem);}
#else /* CONFIG_CGROUPS */
#define CGROUP_SUBSYS_COUNT 0
static inline void cgroup_threadgroup_change_begin(struct task_struct *tsk){ might_sleep();}
static inline void cgroup_threadgroup_change_end(struct task_struct *tsk) {}
#endif /* CONFIG_CGROUPS */
#ifdef CONFIG_SOCK_CGROUP_DATA
/* * sock_cgroup_data is embedded at sock->sk_cgrp_data and contains * per-socket cgroup information except for memcg association. * * On legacy hierarchies, net_prio and net_cls controllers directly * set attributes on each sock which can then be tested by the network * layer. On the default hierarchy, each sock is associated with the * cgroup it was created in and the networking layer can match the * cgroup directly. */struct sock_cgroup_data { struct cgroup *cgroup; /* v2 */#ifdef CONFIG_CGROUP_NET_CLASSID u32 classid; /* v1 */#endif#ifdef CONFIG_CGROUP_NET_PRIO u16 prioidx; /* v1 */#endif};
static inline u16 sock_cgroup_prioidx(const struct sock_cgroup_data *skcd){#ifdef CONFIG_CGROUP_NET_PRIO return READ_ONCE(skcd->prioidx);#else return 1;#endif}
#ifdef CONFIG_CGROUP_NET_CLASSIDstatic inline u32 sock_cgroup_classid(const struct sock_cgroup_data *skcd){ return READ_ONCE(skcd->classid);}#endif
static inline void sock_cgroup_set_prioidx(struct sock_cgroup_data *skcd, u16 prioidx){#ifdef CONFIG_CGROUP_NET_PRIO WRITE_ONCE(skcd->prioidx, prioidx);#endif}
#ifdef CONFIG_CGROUP_NET_CLASSIDstatic inline void sock_cgroup_set_classid(struct sock_cgroup_data *skcd, u32 classid){ WRITE_ONCE(skcd->classid, classid);}#endif
#else /* CONFIG_SOCK_CGROUP_DATA */
struct sock_cgroup_data {};
#endif /* CONFIG_SOCK_CGROUP_DATA */
#endif /* _LINUX_CGROUP_DEFS_H */