diff options
Diffstat (limited to 'include/linux/cgroup-defs.h')
| -rw-r--r-- | include/linux/cgroup-defs.h | 81 |
1 files changed, 58 insertions, 23 deletions
diff --git a/include/linux/cgroup-defs.h b/include/linux/cgroup-defs.h index 8492721b39be..06b77f9dd3f2 100644 --- a/include/linux/cgroup-defs.h +++ b/include/linux/cgroup-defs.h @@ -76,6 +76,7 @@ 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_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 */ /* internal flags, do not use outside cgroup core proper */ __CFTYPE_ONLY_ON_DFL = (1 << 16), /* only on default hierarchy */ @@ -83,6 +84,16 @@ enum { }; /* + * 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; +}; + +/* * Per-subsystem/per-cgroup state maintained by the system. This is the * fundamental structural building block that controllers deal with. * @@ -196,6 +207,9 @@ struct css_set { */ struct list_head e_cset_node[CGROUP_SUBSYS_COUNT]; + /* all css_task_iters currently walking this cset */ + struct list_head task_iters; + /* For RCU-protected deletion */ struct rcu_head rcu_head; }; @@ -217,16 +231,16 @@ struct cgroup { int id; /* - * If this cgroup contains any tasks, it contributes one to - * populated_cnt. All children with non-zero popuplated_cnt of - * their own contribute one. The count is zero iff there's no task - * in this cgroup or its subtree. + * Each non-empty css_set associated with this cgroup contributes + * one to populated_cnt. All children with non-zero popuplated_cnt + * of their own contribute one. The count is zero iff there's no + * task in this cgroup or its subtree. */ int populated_cnt; struct kernfs_node *kn; /* cgroup kernfs entry */ - struct kernfs_node *procs_kn; /* kn for "cgroup.procs" */ - struct kernfs_node *populated_kn; /* kn for "cgroup.subtree_populated" */ + struct cgroup_file procs_file; /* handle for "cgroup.procs" */ + struct cgroup_file events_file; /* handle for "cgroup.events" */ /* * The bitmask of subsystems enabled on the child cgroups. @@ -324,11 +338,6 @@ struct cftype { */ char name[MAX_CFTYPE_NAME]; unsigned long private; - /* - * If not 0, file mode is set to this value, otherwise it will - * be figured out automatically - */ - umode_t mode; /* * The maximum length of string, excluding trailing nul, that can @@ -340,6 +349,14 @@ struct cftype { 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. */ @@ -405,21 +422,16 @@ struct cgroup_subsys { void (*css_reset)(struct cgroup_subsys_state *css); void (*css_e_css_changed)(struct cgroup_subsys_state *css); - int (*can_attach)(struct cgroup_subsys_state *css, - struct cgroup_taskset *tset); - void (*cancel_attach)(struct cgroup_subsys_state *css, - struct cgroup_taskset *tset); - void (*attach)(struct cgroup_subsys_state *css, - struct cgroup_taskset *tset); + 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, void **priv_p); void (*cancel_fork)(struct task_struct *task, void *priv); void (*fork)(struct task_struct *task, void *priv); - void (*exit)(struct cgroup_subsys_state *css, - struct cgroup_subsys_state *old_css, - struct task_struct *task); + void (*exit)(struct task_struct *task); + void (*free)(struct task_struct *task); void (*bind)(struct cgroup_subsys_state *root_css); - int disabled; int early_init; /* @@ -473,8 +485,31 @@ struct cgroup_subsys { unsigned int depends_on; }; -void cgroup_threadgroup_change_begin(struct task_struct *tsk); -void cgroup_threadgroup_change_end(struct task_struct *tsk); +extern struct percpu_rw_semaphore cgroup_threadgroup_rwsem; + +/** + * cgroup_threadgroup_change_begin - threadgroup exclusion for cgroups + * @tsk: target task + * + * Called from threadgroup_change_begin() and allows cgroup operations to + * synchronize against threadgroup changes using a percpu_rw_semaphore. + */ +static inline void cgroup_threadgroup_change_begin(struct task_struct *tsk) +{ + percpu_down_read(&cgroup_threadgroup_rwsem); +} + +/** + * cgroup_threadgroup_change_end - threadgroup exclusion for cgroups + * @tsk: target task + * + * Called from threadgroup_change_end(). Counterpart of + * cgroup_threadcgroup_change_begin(). + */ +static inline void cgroup_threadgroup_change_end(struct task_struct *tsk) +{ + percpu_up_read(&cgroup_threadgroup_rwsem); +} #else /* CONFIG_CGROUPS */ |