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![Peter Zijlstra](/assets/img/avatar_default.png)
Reduce rbtree boiler plate by using the new helpers. One noteworthy change is unification of the various (partial) compare functions. We construct a subtree match by forcing the sub-order to always match, see __group_cmp(). Due to 'const' we had to touch cgroup_id(). Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Acked-by: Tejun Heo <tj@kernel.org> Acked-by: Davidlohr Bueso <dbueso@suse.de>
961 lines
29 KiB
C
961 lines
29 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
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#ifndef _LINUX_CGROUP_H
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#define _LINUX_CGROUP_H
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/*
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* cgroup interface
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*
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* Copyright (C) 2003 BULL SA
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* Copyright (C) 2004-2006 Silicon Graphics, Inc.
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*
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*/
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#include <linux/sched.h>
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#include <linux/cpumask.h>
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#include <linux/nodemask.h>
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#include <linux/rculist.h>
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#include <linux/cgroupstats.h>
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#include <linux/fs.h>
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#include <linux/seq_file.h>
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#include <linux/kernfs.h>
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#include <linux/jump_label.h>
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#include <linux/types.h>
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#include <linux/ns_common.h>
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#include <linux/nsproxy.h>
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#include <linux/user_namespace.h>
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#include <linux/refcount.h>
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#include <linux/kernel_stat.h>
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#include <linux/cgroup-defs.h>
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struct kernel_clone_args;
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#ifdef CONFIG_CGROUPS
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/*
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* All weight knobs on the default hierarhcy should use the following min,
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* default and max values. The default value is the logarithmic center of
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* MIN and MAX and allows 100x to be expressed in both directions.
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*/
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#define CGROUP_WEIGHT_MIN 1
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#define CGROUP_WEIGHT_DFL 100
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#define CGROUP_WEIGHT_MAX 10000
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/* walk only threadgroup leaders */
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#define CSS_TASK_ITER_PROCS (1U << 0)
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/* walk all threaded css_sets in the domain */
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#define CSS_TASK_ITER_THREADED (1U << 1)
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/* internal flags */
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#define CSS_TASK_ITER_SKIPPED (1U << 16)
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/* a css_task_iter should be treated as an opaque object */
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struct css_task_iter {
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struct cgroup_subsys *ss;
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unsigned int flags;
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struct list_head *cset_pos;
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struct list_head *cset_head;
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struct list_head *tcset_pos;
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struct list_head *tcset_head;
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struct list_head *task_pos;
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struct list_head *cur_tasks_head;
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struct css_set *cur_cset;
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struct css_set *cur_dcset;
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struct task_struct *cur_task;
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struct list_head iters_node; /* css_set->task_iters */
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};
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extern struct cgroup_root cgrp_dfl_root;
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extern struct css_set init_css_set;
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#define SUBSYS(_x) extern struct cgroup_subsys _x ## _cgrp_subsys;
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#include <linux/cgroup_subsys.h>
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#undef SUBSYS
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#define SUBSYS(_x) \
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extern struct static_key_true _x ## _cgrp_subsys_enabled_key; \
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extern struct static_key_true _x ## _cgrp_subsys_on_dfl_key;
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#include <linux/cgroup_subsys.h>
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#undef SUBSYS
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/**
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* cgroup_subsys_enabled - fast test on whether a subsys is enabled
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* @ss: subsystem in question
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*/
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#define cgroup_subsys_enabled(ss) \
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static_branch_likely(&ss ## _enabled_key)
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/**
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* cgroup_subsys_on_dfl - fast test on whether a subsys is on default hierarchy
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* @ss: subsystem in question
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*/
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#define cgroup_subsys_on_dfl(ss) \
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static_branch_likely(&ss ## _on_dfl_key)
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bool css_has_online_children(struct cgroup_subsys_state *css);
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struct cgroup_subsys_state *css_from_id(int id, struct cgroup_subsys *ss);
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struct cgroup_subsys_state *cgroup_e_css(struct cgroup *cgroup,
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struct cgroup_subsys *ss);
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struct cgroup_subsys_state *cgroup_get_e_css(struct cgroup *cgroup,
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struct cgroup_subsys *ss);
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struct cgroup_subsys_state *css_tryget_online_from_dir(struct dentry *dentry,
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struct cgroup_subsys *ss);
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struct cgroup *cgroup_get_from_path(const char *path);
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struct cgroup *cgroup_get_from_fd(int fd);
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int cgroup_attach_task_all(struct task_struct *from, struct task_struct *);
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int cgroup_transfer_tasks(struct cgroup *to, struct cgroup *from);
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int cgroup_add_dfl_cftypes(struct cgroup_subsys *ss, struct cftype *cfts);
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int cgroup_add_legacy_cftypes(struct cgroup_subsys *ss, struct cftype *cfts);
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int cgroup_rm_cftypes(struct cftype *cfts);
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void cgroup_file_notify(struct cgroup_file *cfile);
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int task_cgroup_path(struct task_struct *task, char *buf, size_t buflen);
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int cgroupstats_build(struct cgroupstats *stats, struct dentry *dentry);
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int proc_cgroup_show(struct seq_file *m, struct pid_namespace *ns,
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struct pid *pid, struct task_struct *tsk);
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void cgroup_fork(struct task_struct *p);
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extern int cgroup_can_fork(struct task_struct *p,
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struct kernel_clone_args *kargs);
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extern void cgroup_cancel_fork(struct task_struct *p,
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struct kernel_clone_args *kargs);
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extern void cgroup_post_fork(struct task_struct *p,
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struct kernel_clone_args *kargs);
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void cgroup_exit(struct task_struct *p);
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void cgroup_release(struct task_struct *p);
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void cgroup_free(struct task_struct *p);
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int cgroup_init_early(void);
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int cgroup_init(void);
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int cgroup_parse_float(const char *input, unsigned dec_shift, s64 *v);
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/*
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* Iteration helpers and macros.
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*/
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struct cgroup_subsys_state *css_next_child(struct cgroup_subsys_state *pos,
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struct cgroup_subsys_state *parent);
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struct cgroup_subsys_state *css_next_descendant_pre(struct cgroup_subsys_state *pos,
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struct cgroup_subsys_state *css);
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struct cgroup_subsys_state *css_rightmost_descendant(struct cgroup_subsys_state *pos);
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struct cgroup_subsys_state *css_next_descendant_post(struct cgroup_subsys_state *pos,
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struct cgroup_subsys_state *css);
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struct task_struct *cgroup_taskset_first(struct cgroup_taskset *tset,
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struct cgroup_subsys_state **dst_cssp);
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struct task_struct *cgroup_taskset_next(struct cgroup_taskset *tset,
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struct cgroup_subsys_state **dst_cssp);
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void css_task_iter_start(struct cgroup_subsys_state *css, unsigned int flags,
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struct css_task_iter *it);
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struct task_struct *css_task_iter_next(struct css_task_iter *it);
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void css_task_iter_end(struct css_task_iter *it);
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/**
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* css_for_each_child - iterate through children of a css
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* @pos: the css * to use as the loop cursor
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* @parent: css whose children to walk
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*
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* Walk @parent's children. Must be called under rcu_read_lock().
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*
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* If a subsystem synchronizes ->css_online() and the start of iteration, a
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* css which finished ->css_online() is guaranteed to be visible in the
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* future iterations and will stay visible until the last reference is put.
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* A css which hasn't finished ->css_online() or already finished
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* ->css_offline() may show up during traversal. It's each subsystem's
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* responsibility to synchronize against on/offlining.
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*
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* It is allowed to temporarily drop RCU read lock during iteration. The
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* caller is responsible for ensuring that @pos remains accessible until
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* the start of the next iteration by, for example, bumping the css refcnt.
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*/
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#define css_for_each_child(pos, parent) \
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for ((pos) = css_next_child(NULL, (parent)); (pos); \
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(pos) = css_next_child((pos), (parent)))
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/**
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* css_for_each_descendant_pre - pre-order walk of a css's descendants
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* @pos: the css * to use as the loop cursor
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* @root: css whose descendants to walk
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*
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* Walk @root's descendants. @root is included in the iteration and the
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* first node to be visited. Must be called under rcu_read_lock().
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*
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* If a subsystem synchronizes ->css_online() and the start of iteration, a
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* css which finished ->css_online() is guaranteed to be visible in the
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* future iterations and will stay visible until the last reference is put.
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* A css which hasn't finished ->css_online() or already finished
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* ->css_offline() may show up during traversal. It's each subsystem's
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* responsibility to synchronize against on/offlining.
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*
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* For example, the following guarantees that a descendant can't escape
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* state updates of its ancestors.
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*
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* my_online(@css)
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* {
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* Lock @css's parent and @css;
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* Inherit state from the parent;
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* Unlock both.
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* }
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*
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* my_update_state(@css)
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* {
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* css_for_each_descendant_pre(@pos, @css) {
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* Lock @pos;
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* if (@pos == @css)
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* Update @css's state;
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* else
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* Verify @pos is alive and inherit state from its parent;
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* Unlock @pos;
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* }
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* }
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*
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* As long as the inheriting step, including checking the parent state, is
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* enclosed inside @pos locking, double-locking the parent isn't necessary
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* while inheriting. The state update to the parent is guaranteed to be
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* visible by walking order and, as long as inheriting operations to the
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* same @pos are atomic to each other, multiple updates racing each other
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* still result in the correct state. It's guaranateed that at least one
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* inheritance happens for any css after the latest update to its parent.
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*
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* If checking parent's state requires locking the parent, each inheriting
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* iteration should lock and unlock both @pos->parent and @pos.
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*
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* Alternatively, a subsystem may choose to use a single global lock to
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* synchronize ->css_online() and ->css_offline() against tree-walking
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* operations.
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*
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* It is allowed to temporarily drop RCU read lock during iteration. The
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* caller is responsible for ensuring that @pos remains accessible until
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* the start of the next iteration by, for example, bumping the css refcnt.
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*/
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#define css_for_each_descendant_pre(pos, css) \
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for ((pos) = css_next_descendant_pre(NULL, (css)); (pos); \
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(pos) = css_next_descendant_pre((pos), (css)))
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/**
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* css_for_each_descendant_post - post-order walk of a css's descendants
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* @pos: the css * to use as the loop cursor
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* @css: css whose descendants to walk
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*
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* Similar to css_for_each_descendant_pre() but performs post-order
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* traversal instead. @root is included in the iteration and the last
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* node to be visited.
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*
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* If a subsystem synchronizes ->css_online() and the start of iteration, a
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* css which finished ->css_online() is guaranteed to be visible in the
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* future iterations and will stay visible until the last reference is put.
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* A css which hasn't finished ->css_online() or already finished
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* ->css_offline() may show up during traversal. It's each subsystem's
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* responsibility to synchronize against on/offlining.
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*
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* Note that the walk visibility guarantee example described in pre-order
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* walk doesn't apply the same to post-order walks.
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*/
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#define css_for_each_descendant_post(pos, css) \
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for ((pos) = css_next_descendant_post(NULL, (css)); (pos); \
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(pos) = css_next_descendant_post((pos), (css)))
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/**
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* cgroup_taskset_for_each - iterate cgroup_taskset
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* @task: the loop cursor
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* @dst_css: the destination css
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* @tset: taskset to iterate
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*
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* @tset may contain multiple tasks and they may belong to multiple
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* processes.
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*
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* On the v2 hierarchy, there may be tasks from multiple processes and they
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* may not share the source or destination csses.
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*
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* On traditional hierarchies, when there are multiple tasks in @tset, if a
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* task of a process is in @tset, all tasks of the process are in @tset.
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* Also, all are guaranteed to share the same source and destination csses.
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*
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* Iteration is not in any specific order.
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*/
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#define cgroup_taskset_for_each(task, dst_css, tset) \
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for ((task) = cgroup_taskset_first((tset), &(dst_css)); \
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(task); \
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(task) = cgroup_taskset_next((tset), &(dst_css)))
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/**
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* cgroup_taskset_for_each_leader - iterate group leaders in a cgroup_taskset
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* @leader: the loop cursor
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* @dst_css: the destination css
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* @tset: taskset to iterate
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*
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* Iterate threadgroup leaders of @tset. For single-task migrations, @tset
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* may not contain any.
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*/
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#define cgroup_taskset_for_each_leader(leader, dst_css, tset) \
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for ((leader) = cgroup_taskset_first((tset), &(dst_css)); \
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(leader); \
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(leader) = cgroup_taskset_next((tset), &(dst_css))) \
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if ((leader) != (leader)->group_leader) \
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; \
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else
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/*
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* Inline functions.
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*/
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static inline u64 cgroup_id(const struct cgroup *cgrp)
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{
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return cgrp->kn->id;
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}
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/**
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* css_get - obtain a reference on the specified css
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* @css: target css
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*
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* The caller must already have a reference.
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*/
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static inline void css_get(struct cgroup_subsys_state *css)
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{
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if (!(css->flags & CSS_NO_REF))
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percpu_ref_get(&css->refcnt);
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}
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/**
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* css_get_many - obtain references on the specified css
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* @css: target css
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* @n: number of references to get
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*
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* The caller must already have a reference.
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*/
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static inline void css_get_many(struct cgroup_subsys_state *css, unsigned int n)
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{
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if (!(css->flags & CSS_NO_REF))
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percpu_ref_get_many(&css->refcnt, n);
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}
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/**
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* css_tryget - try to obtain a reference on the specified css
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* @css: target css
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*
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* Obtain a reference on @css unless it already has reached zero and is
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* being released. This function doesn't care whether @css is on or
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* offline. The caller naturally needs to ensure that @css is accessible
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* but doesn't have to be holding a reference on it - IOW, RCU protected
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* access is good enough for this function. Returns %true if a reference
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* count was successfully obtained; %false otherwise.
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*/
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static inline bool css_tryget(struct cgroup_subsys_state *css)
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{
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if (!(css->flags & CSS_NO_REF))
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return percpu_ref_tryget(&css->refcnt);
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return true;
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}
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/**
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* css_tryget_online - try to obtain a reference on the specified css if online
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* @css: target css
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*
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* Obtain a reference on @css if it's online. The caller naturally needs
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* to ensure that @css is accessible but doesn't have to be holding a
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* reference on it - IOW, RCU protected access is good enough for this
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* function. Returns %true if a reference count was successfully obtained;
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* %false otherwise.
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*/
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static inline bool css_tryget_online(struct cgroup_subsys_state *css)
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{
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if (!(css->flags & CSS_NO_REF))
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return percpu_ref_tryget_live(&css->refcnt);
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return true;
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}
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/**
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* css_is_dying - test whether the specified css is dying
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* @css: target css
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*
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* Test whether @css is in the process of offlining or already offline. In
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* most cases, ->css_online() and ->css_offline() callbacks should be
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* enough; however, the actual offline operations are RCU delayed and this
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* test returns %true also when @css is scheduled to be offlined.
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*
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* This is useful, for example, when the use case requires synchronous
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* behavior with respect to cgroup removal. cgroup removal schedules css
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* offlining but the css can seem alive while the operation is being
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* delayed. If the delay affects user visible semantics, this test can be
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* used to resolve the situation.
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*/
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static inline bool css_is_dying(struct cgroup_subsys_state *css)
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{
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return !(css->flags & CSS_NO_REF) && percpu_ref_is_dying(&css->refcnt);
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}
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/**
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* css_put - put a css reference
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* @css: target css
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*
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* Put a reference obtained via css_get() and css_tryget_online().
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*/
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static inline void css_put(struct cgroup_subsys_state *css)
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{
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if (!(css->flags & CSS_NO_REF))
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percpu_ref_put(&css->refcnt);
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}
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/**
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* css_put_many - put css references
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* @css: target css
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* @n: number of references to put
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*
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* Put references obtained via css_get() and css_tryget_online().
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*/
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static inline void css_put_many(struct cgroup_subsys_state *css, unsigned int n)
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{
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if (!(css->flags & CSS_NO_REF))
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percpu_ref_put_many(&css->refcnt, n);
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}
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static inline void cgroup_get(struct cgroup *cgrp)
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{
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css_get(&cgrp->self);
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}
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static inline bool cgroup_tryget(struct cgroup *cgrp)
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{
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return css_tryget(&cgrp->self);
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}
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static inline void cgroup_put(struct cgroup *cgrp)
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{
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css_put(&cgrp->self);
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}
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/**
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* task_css_set_check - obtain a task's css_set with extra access conditions
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* @task: the task to obtain css_set for
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* @__c: extra condition expression to be passed to rcu_dereference_check()
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*
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* A task's css_set is RCU protected, initialized and exited while holding
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* task_lock(), and can only be modified while holding both cgroup_mutex
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* and task_lock() while the task is alive. This macro verifies that the
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* caller is inside proper critical section and returns @task's css_set.
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*
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* The caller can also specify additional allowed conditions via @__c, such
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* as locks used during the cgroup_subsys::attach() methods.
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*/
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#ifdef CONFIG_PROVE_RCU
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extern struct mutex cgroup_mutex;
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extern spinlock_t css_set_lock;
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#define task_css_set_check(task, __c) \
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rcu_dereference_check((task)->cgroups, \
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lockdep_is_held(&cgroup_mutex) || \
|
|
lockdep_is_held(&css_set_lock) || \
|
|
((task)->flags & PF_EXITING) || (__c))
|
|
#else
|
|
#define task_css_set_check(task, __c) \
|
|
rcu_dereference((task)->cgroups)
|
|
#endif
|
|
|
|
/**
|
|
* task_css_check - obtain css for (task, subsys) w/ extra access conds
|
|
* @task: the target task
|
|
* @subsys_id: the target subsystem ID
|
|
* @__c: extra condition expression to be passed to rcu_dereference_check()
|
|
*
|
|
* Return the cgroup_subsys_state for the (@task, @subsys_id) pair. The
|
|
* synchronization rules are the same as task_css_set_check().
|
|
*/
|
|
#define task_css_check(task, subsys_id, __c) \
|
|
task_css_set_check((task), (__c))->subsys[(subsys_id)]
|
|
|
|
/**
|
|
* task_css_set - obtain a task's css_set
|
|
* @task: the task to obtain css_set for
|
|
*
|
|
* See task_css_set_check().
|
|
*/
|
|
static inline struct css_set *task_css_set(struct task_struct *task)
|
|
{
|
|
return task_css_set_check(task, false);
|
|
}
|
|
|
|
/**
|
|
* task_css - obtain css for (task, subsys)
|
|
* @task: the target task
|
|
* @subsys_id: the target subsystem ID
|
|
*
|
|
* See task_css_check().
|
|
*/
|
|
static inline struct cgroup_subsys_state *task_css(struct task_struct *task,
|
|
int subsys_id)
|
|
{
|
|
return task_css_check(task, subsys_id, false);
|
|
}
|
|
|
|
/**
|
|
* task_get_css - find and get the css for (task, subsys)
|
|
* @task: the target task
|
|
* @subsys_id: the target subsystem ID
|
|
*
|
|
* Find the css for the (@task, @subsys_id) combination, increment a
|
|
* reference on and return it. This function is guaranteed to return a
|
|
* valid css. The returned css may already have been offlined.
|
|
*/
|
|
static inline struct cgroup_subsys_state *
|
|
task_get_css(struct task_struct *task, int subsys_id)
|
|
{
|
|
struct cgroup_subsys_state *css;
|
|
|
|
rcu_read_lock();
|
|
while (true) {
|
|
css = task_css(task, subsys_id);
|
|
/*
|
|
* Can't use css_tryget_online() here. A task which has
|
|
* PF_EXITING set may stay associated with an offline css.
|
|
* If such task calls this function, css_tryget_online()
|
|
* will keep failing.
|
|
*/
|
|
if (likely(css_tryget(css)))
|
|
break;
|
|
cpu_relax();
|
|
}
|
|
rcu_read_unlock();
|
|
return css;
|
|
}
|
|
|
|
/**
|
|
* task_css_is_root - test whether a task belongs to the root css
|
|
* @task: the target task
|
|
* @subsys_id: the target subsystem ID
|
|
*
|
|
* Test whether @task belongs to the root css on the specified subsystem.
|
|
* May be invoked in any context.
|
|
*/
|
|
static inline bool task_css_is_root(struct task_struct *task, int subsys_id)
|
|
{
|
|
return task_css_check(task, subsys_id, true) ==
|
|
init_css_set.subsys[subsys_id];
|
|
}
|
|
|
|
static inline struct cgroup *task_cgroup(struct task_struct *task,
|
|
int subsys_id)
|
|
{
|
|
return task_css(task, subsys_id)->cgroup;
|
|
}
|
|
|
|
static inline struct cgroup *task_dfl_cgroup(struct task_struct *task)
|
|
{
|
|
return task_css_set(task)->dfl_cgrp;
|
|
}
|
|
|
|
static inline struct cgroup *cgroup_parent(struct cgroup *cgrp)
|
|
{
|
|
struct cgroup_subsys_state *parent_css = cgrp->self.parent;
|
|
|
|
if (parent_css)
|
|
return container_of(parent_css, struct cgroup, self);
|
|
return NULL;
|
|
}
|
|
|
|
/**
|
|
* cgroup_is_descendant - test ancestry
|
|
* @cgrp: the cgroup to be tested
|
|
* @ancestor: possible ancestor of @cgrp
|
|
*
|
|
* Test whether @cgrp is a descendant of @ancestor. It also returns %true
|
|
* if @cgrp == @ancestor. This function is safe to call as long as @cgrp
|
|
* and @ancestor are accessible.
|
|
*/
|
|
static inline bool cgroup_is_descendant(struct cgroup *cgrp,
|
|
struct cgroup *ancestor)
|
|
{
|
|
if (cgrp->root != ancestor->root || cgrp->level < ancestor->level)
|
|
return false;
|
|
return cgrp->ancestor_ids[ancestor->level] == cgroup_id(ancestor);
|
|
}
|
|
|
|
/**
|
|
* cgroup_ancestor - find ancestor of cgroup
|
|
* @cgrp: cgroup to find ancestor of
|
|
* @ancestor_level: level of ancestor to find starting from root
|
|
*
|
|
* Find ancestor of cgroup at specified level starting from root if it exists
|
|
* and return pointer to it. Return NULL if @cgrp doesn't have ancestor at
|
|
* @ancestor_level.
|
|
*
|
|
* This function is safe to call as long as @cgrp is accessible.
|
|
*/
|
|
static inline struct cgroup *cgroup_ancestor(struct cgroup *cgrp,
|
|
int ancestor_level)
|
|
{
|
|
if (cgrp->level < ancestor_level)
|
|
return NULL;
|
|
while (cgrp && cgrp->level > ancestor_level)
|
|
cgrp = cgroup_parent(cgrp);
|
|
return cgrp;
|
|
}
|
|
|
|
/**
|
|
* task_under_cgroup_hierarchy - test task's membership of cgroup ancestry
|
|
* @task: the task to be tested
|
|
* @ancestor: possible ancestor of @task's cgroup
|
|
*
|
|
* Tests whether @task's default cgroup hierarchy is a descendant of @ancestor.
|
|
* It follows all the same rules as cgroup_is_descendant, and only applies
|
|
* to the default hierarchy.
|
|
*/
|
|
static inline bool task_under_cgroup_hierarchy(struct task_struct *task,
|
|
struct cgroup *ancestor)
|
|
{
|
|
struct css_set *cset = task_css_set(task);
|
|
|
|
return cgroup_is_descendant(cset->dfl_cgrp, ancestor);
|
|
}
|
|
|
|
/* no synchronization, the result can only be used as a hint */
|
|
static inline bool cgroup_is_populated(struct cgroup *cgrp)
|
|
{
|
|
return cgrp->nr_populated_csets + cgrp->nr_populated_domain_children +
|
|
cgrp->nr_populated_threaded_children;
|
|
}
|
|
|
|
/* returns ino associated with a cgroup */
|
|
static inline ino_t cgroup_ino(struct cgroup *cgrp)
|
|
{
|
|
return kernfs_ino(cgrp->kn);
|
|
}
|
|
|
|
/* cft/css accessors for cftype->write() operation */
|
|
static inline struct cftype *of_cft(struct kernfs_open_file *of)
|
|
{
|
|
return of->kn->priv;
|
|
}
|
|
|
|
struct cgroup_subsys_state *of_css(struct kernfs_open_file *of);
|
|
|
|
/* cft/css accessors for cftype->seq_*() operations */
|
|
static inline struct cftype *seq_cft(struct seq_file *seq)
|
|
{
|
|
return of_cft(seq->private);
|
|
}
|
|
|
|
static inline struct cgroup_subsys_state *seq_css(struct seq_file *seq)
|
|
{
|
|
return of_css(seq->private);
|
|
}
|
|
|
|
/*
|
|
* Name / path handling functions. All are thin wrappers around the kernfs
|
|
* counterparts and can be called under any context.
|
|
*/
|
|
|
|
static inline int cgroup_name(struct cgroup *cgrp, char *buf, size_t buflen)
|
|
{
|
|
return kernfs_name(cgrp->kn, buf, buflen);
|
|
}
|
|
|
|
static inline int cgroup_path(struct cgroup *cgrp, char *buf, size_t buflen)
|
|
{
|
|
return kernfs_path(cgrp->kn, buf, buflen);
|
|
}
|
|
|
|
static inline void pr_cont_cgroup_name(struct cgroup *cgrp)
|
|
{
|
|
pr_cont_kernfs_name(cgrp->kn);
|
|
}
|
|
|
|
static inline void pr_cont_cgroup_path(struct cgroup *cgrp)
|
|
{
|
|
pr_cont_kernfs_path(cgrp->kn);
|
|
}
|
|
|
|
static inline struct psi_group *cgroup_psi(struct cgroup *cgrp)
|
|
{
|
|
return &cgrp->psi;
|
|
}
|
|
|
|
static inline void cgroup_init_kthreadd(void)
|
|
{
|
|
/*
|
|
* kthreadd is inherited by all kthreads, keep it in the root so
|
|
* that the new kthreads are guaranteed to stay in the root until
|
|
* initialization is finished.
|
|
*/
|
|
current->no_cgroup_migration = 1;
|
|
}
|
|
|
|
static inline void cgroup_kthread_ready(void)
|
|
{
|
|
/*
|
|
* This kthread finished initialization. The creator should have
|
|
* set PF_NO_SETAFFINITY if this kthread should stay in the root.
|
|
*/
|
|
current->no_cgroup_migration = 0;
|
|
}
|
|
|
|
void cgroup_path_from_kernfs_id(u64 id, char *buf, size_t buflen);
|
|
#else /* !CONFIG_CGROUPS */
|
|
|
|
struct cgroup_subsys_state;
|
|
struct cgroup;
|
|
|
|
static inline u64 cgroup_id(const struct cgroup *cgrp) { return 1; }
|
|
static inline void css_get(struct cgroup_subsys_state *css) {}
|
|
static inline void css_put(struct cgroup_subsys_state *css) {}
|
|
static inline int cgroup_attach_task_all(struct task_struct *from,
|
|
struct task_struct *t) { return 0; }
|
|
static inline int cgroupstats_build(struct cgroupstats *stats,
|
|
struct dentry *dentry) { return -EINVAL; }
|
|
|
|
static inline void cgroup_fork(struct task_struct *p) {}
|
|
static inline int cgroup_can_fork(struct task_struct *p,
|
|
struct kernel_clone_args *kargs) { return 0; }
|
|
static inline void cgroup_cancel_fork(struct task_struct *p,
|
|
struct kernel_clone_args *kargs) {}
|
|
static inline void cgroup_post_fork(struct task_struct *p,
|
|
struct kernel_clone_args *kargs) {}
|
|
static inline void cgroup_exit(struct task_struct *p) {}
|
|
static inline void cgroup_release(struct task_struct *p) {}
|
|
static inline void cgroup_free(struct task_struct *p) {}
|
|
|
|
static inline int cgroup_init_early(void) { return 0; }
|
|
static inline int cgroup_init(void) { return 0; }
|
|
static inline void cgroup_init_kthreadd(void) {}
|
|
static inline void cgroup_kthread_ready(void) {}
|
|
|
|
static inline struct cgroup *cgroup_parent(struct cgroup *cgrp)
|
|
{
|
|
return NULL;
|
|
}
|
|
|
|
static inline struct psi_group *cgroup_psi(struct cgroup *cgrp)
|
|
{
|
|
return NULL;
|
|
}
|
|
|
|
static inline bool task_under_cgroup_hierarchy(struct task_struct *task,
|
|
struct cgroup *ancestor)
|
|
{
|
|
return true;
|
|
}
|
|
|
|
static inline void cgroup_path_from_kernfs_id(u64 id, char *buf, size_t buflen)
|
|
{}
|
|
#endif /* !CONFIG_CGROUPS */
|
|
|
|
#ifdef CONFIG_CGROUPS
|
|
/*
|
|
* cgroup scalable recursive statistics.
|
|
*/
|
|
void cgroup_rstat_updated(struct cgroup *cgrp, int cpu);
|
|
void cgroup_rstat_flush(struct cgroup *cgrp);
|
|
void cgroup_rstat_flush_irqsafe(struct cgroup *cgrp);
|
|
void cgroup_rstat_flush_hold(struct cgroup *cgrp);
|
|
void cgroup_rstat_flush_release(void);
|
|
|
|
/*
|
|
* Basic resource stats.
|
|
*/
|
|
#ifdef CONFIG_CGROUP_CPUACCT
|
|
void cpuacct_charge(struct task_struct *tsk, u64 cputime);
|
|
void cpuacct_account_field(struct task_struct *tsk, int index, u64 val);
|
|
#else
|
|
static inline void cpuacct_charge(struct task_struct *tsk, u64 cputime) {}
|
|
static inline void cpuacct_account_field(struct task_struct *tsk, int index,
|
|
u64 val) {}
|
|
#endif
|
|
|
|
void __cgroup_account_cputime(struct cgroup *cgrp, u64 delta_exec);
|
|
void __cgroup_account_cputime_field(struct cgroup *cgrp,
|
|
enum cpu_usage_stat index, u64 delta_exec);
|
|
|
|
static inline void cgroup_account_cputime(struct task_struct *task,
|
|
u64 delta_exec)
|
|
{
|
|
struct cgroup *cgrp;
|
|
|
|
cpuacct_charge(task, delta_exec);
|
|
|
|
rcu_read_lock();
|
|
cgrp = task_dfl_cgroup(task);
|
|
if (cgroup_parent(cgrp))
|
|
__cgroup_account_cputime(cgrp, delta_exec);
|
|
rcu_read_unlock();
|
|
}
|
|
|
|
static inline void cgroup_account_cputime_field(struct task_struct *task,
|
|
enum cpu_usage_stat index,
|
|
u64 delta_exec)
|
|
{
|
|
struct cgroup *cgrp;
|
|
|
|
cpuacct_account_field(task, index, delta_exec);
|
|
|
|
rcu_read_lock();
|
|
cgrp = task_dfl_cgroup(task);
|
|
if (cgroup_parent(cgrp))
|
|
__cgroup_account_cputime_field(cgrp, index, delta_exec);
|
|
rcu_read_unlock();
|
|
}
|
|
|
|
#else /* CONFIG_CGROUPS */
|
|
|
|
static inline void cgroup_account_cputime(struct task_struct *task,
|
|
u64 delta_exec) {}
|
|
static inline void cgroup_account_cputime_field(struct task_struct *task,
|
|
enum cpu_usage_stat index,
|
|
u64 delta_exec) {}
|
|
|
|
#endif /* CONFIG_CGROUPS */
|
|
|
|
/*
|
|
* sock->sk_cgrp_data handling. For more info, see sock_cgroup_data
|
|
* definition in cgroup-defs.h.
|
|
*/
|
|
#ifdef CONFIG_SOCK_CGROUP_DATA
|
|
|
|
#if defined(CONFIG_CGROUP_NET_PRIO) || defined(CONFIG_CGROUP_NET_CLASSID)
|
|
extern spinlock_t cgroup_sk_update_lock;
|
|
#endif
|
|
|
|
void cgroup_sk_alloc_disable(void);
|
|
void cgroup_sk_alloc(struct sock_cgroup_data *skcd);
|
|
void cgroup_sk_clone(struct sock_cgroup_data *skcd);
|
|
void cgroup_sk_free(struct sock_cgroup_data *skcd);
|
|
|
|
static inline struct cgroup *sock_cgroup_ptr(struct sock_cgroup_data *skcd)
|
|
{
|
|
#if defined(CONFIG_CGROUP_NET_PRIO) || defined(CONFIG_CGROUP_NET_CLASSID)
|
|
unsigned long v;
|
|
|
|
/*
|
|
* @skcd->val is 64bit but the following is safe on 32bit too as we
|
|
* just need the lower ulong to be written and read atomically.
|
|
*/
|
|
v = READ_ONCE(skcd->val);
|
|
|
|
if (v & 3)
|
|
return &cgrp_dfl_root.cgrp;
|
|
|
|
return (struct cgroup *)(unsigned long)v ?: &cgrp_dfl_root.cgrp;
|
|
#else
|
|
return (struct cgroup *)(unsigned long)skcd->val;
|
|
#endif
|
|
}
|
|
|
|
#else /* CONFIG_CGROUP_DATA */
|
|
|
|
static inline void cgroup_sk_alloc(struct sock_cgroup_data *skcd) {}
|
|
static inline void cgroup_sk_clone(struct sock_cgroup_data *skcd) {}
|
|
static inline void cgroup_sk_free(struct sock_cgroup_data *skcd) {}
|
|
|
|
#endif /* CONFIG_CGROUP_DATA */
|
|
|
|
struct cgroup_namespace {
|
|
struct ns_common ns;
|
|
struct user_namespace *user_ns;
|
|
struct ucounts *ucounts;
|
|
struct css_set *root_cset;
|
|
};
|
|
|
|
extern struct cgroup_namespace init_cgroup_ns;
|
|
|
|
#ifdef CONFIG_CGROUPS
|
|
|
|
void free_cgroup_ns(struct cgroup_namespace *ns);
|
|
|
|
struct cgroup_namespace *copy_cgroup_ns(unsigned long flags,
|
|
struct user_namespace *user_ns,
|
|
struct cgroup_namespace *old_ns);
|
|
|
|
int cgroup_path_ns(struct cgroup *cgrp, char *buf, size_t buflen,
|
|
struct cgroup_namespace *ns);
|
|
|
|
#else /* !CONFIG_CGROUPS */
|
|
|
|
static inline void free_cgroup_ns(struct cgroup_namespace *ns) { }
|
|
static inline struct cgroup_namespace *
|
|
copy_cgroup_ns(unsigned long flags, struct user_namespace *user_ns,
|
|
struct cgroup_namespace *old_ns)
|
|
{
|
|
return old_ns;
|
|
}
|
|
|
|
#endif /* !CONFIG_CGROUPS */
|
|
|
|
static inline void get_cgroup_ns(struct cgroup_namespace *ns)
|
|
{
|
|
if (ns)
|
|
refcount_inc(&ns->ns.count);
|
|
}
|
|
|
|
static inline void put_cgroup_ns(struct cgroup_namespace *ns)
|
|
{
|
|
if (ns && refcount_dec_and_test(&ns->ns.count))
|
|
free_cgroup_ns(ns);
|
|
}
|
|
|
|
#ifdef CONFIG_CGROUPS
|
|
|
|
void cgroup_enter_frozen(void);
|
|
void cgroup_leave_frozen(bool always_leave);
|
|
void cgroup_update_frozen(struct cgroup *cgrp);
|
|
void cgroup_freeze(struct cgroup *cgrp, bool freeze);
|
|
void cgroup_freezer_migrate_task(struct task_struct *task, struct cgroup *src,
|
|
struct cgroup *dst);
|
|
|
|
static inline bool cgroup_task_freeze(struct task_struct *task)
|
|
{
|
|
bool ret;
|
|
|
|
if (task->flags & PF_KTHREAD)
|
|
return false;
|
|
|
|
rcu_read_lock();
|
|
ret = test_bit(CGRP_FREEZE, &task_dfl_cgroup(task)->flags);
|
|
rcu_read_unlock();
|
|
|
|
return ret;
|
|
}
|
|
|
|
static inline bool cgroup_task_frozen(struct task_struct *task)
|
|
{
|
|
return task->frozen;
|
|
}
|
|
|
|
#else /* !CONFIG_CGROUPS */
|
|
|
|
static inline void cgroup_enter_frozen(void) { }
|
|
static inline void cgroup_leave_frozen(bool always_leave) { }
|
|
static inline bool cgroup_task_freeze(struct task_struct *task)
|
|
{
|
|
return false;
|
|
}
|
|
static inline bool cgroup_task_frozen(struct task_struct *task)
|
|
{
|
|
return false;
|
|
}
|
|
|
|
#endif /* !CONFIG_CGROUPS */
|
|
|
|
#ifdef CONFIG_CGROUP_BPF
|
|
static inline void cgroup_bpf_get(struct cgroup *cgrp)
|
|
{
|
|
percpu_ref_get(&cgrp->bpf.refcnt);
|
|
}
|
|
|
|
static inline void cgroup_bpf_put(struct cgroup *cgrp)
|
|
{
|
|
percpu_ref_put(&cgrp->bpf.refcnt);
|
|
}
|
|
|
|
#else /* CONFIG_CGROUP_BPF */
|
|
|
|
static inline void cgroup_bpf_get(struct cgroup *cgrp) {}
|
|
static inline void cgroup_bpf_put(struct cgroup *cgrp) {}
|
|
|
|
#endif /* CONFIG_CGROUP_BPF */
|
|
|
|
#endif /* _LINUX_CGROUP_H */
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