diff options
| -rw-r--r-- | include/linux/cgroup.h | 3 | ||||
| -rw-r--r-- | kernel/cgroup.c | 109 | ||||
| -rw-r--r-- | kernel/cpuset.c | 2 |
3 files changed, 23 insertions, 91 deletions
diff --git a/include/linux/cgroup.h b/include/linux/cgroup.h index 7e818a3ef60a..01c48c6806d6 100644 --- a/include/linux/cgroup.h +++ b/include/linux/cgroup.h @@ -693,7 +693,8 @@ struct task_struct *cgroup_iter_next(struct cgroup *cgrp, struct cgroup_iter *it); void cgroup_iter_end(struct cgroup *cgrp, struct cgroup_iter *it); int cgroup_scan_tasks(struct cgroup_scanner *scan); -int cgroup_attach_task(struct cgroup *, struct task_struct *); +int cgroup_attach_task(struct cgroup *cgrp, struct task_struct *tsk, + bool threadgroup); int cgroup_attach_task_all(struct task_struct *from, struct task_struct *); /* diff --git a/kernel/cgroup.c b/kernel/cgroup.c index 54689fc008f6..04fa2abf94b2 100644 --- a/kernel/cgroup.c +++ b/kernel/cgroup.c @@ -59,7 +59,7 @@ #include <linux/vmalloc.h> /* TODO: replace with more sophisticated array */ #include <linux/eventfd.h> #include <linux/poll.h> -#include <linux/flex_array.h> /* used in cgroup_attach_proc */ +#include <linux/flex_array.h> /* used in cgroup_attach_task */ #include <linux/kthread.h> #include <linux/atomic.h> @@ -1944,82 +1944,6 @@ static void cgroup_task_migrate(struct cgroup *cgrp, struct cgroup *oldcgrp, } /** - * cgroup_attach_task - attach task 'tsk' to cgroup 'cgrp' - * @cgrp: the cgroup the task is attaching to - * @tsk: the task to be attached - * - * Call with cgroup_mutex and threadgroup locked. May take task_lock of - * @tsk during call. - */ -int cgroup_attach_task(struct cgroup *cgrp, struct task_struct *tsk) -{ - int retval = 0; - struct cgroup_subsys *ss, *failed_ss = NULL; - struct cgroup *oldcgrp; - struct cgroupfs_root *root = cgrp->root; - struct cgroup_taskset tset = { }; - struct css_set *newcg; - - /* @tsk either already exited or can't exit until the end */ - if (tsk->flags & PF_EXITING) - return -ESRCH; - - /* Nothing to do if the task is already in that cgroup */ - oldcgrp = task_cgroup_from_root(tsk, root); - if (cgrp == oldcgrp) - return 0; - - tset.single.task = tsk; - tset.single.cgrp = oldcgrp; - - for_each_subsys(root, ss) { - if (ss->can_attach) { - retval = ss->can_attach(cgrp, &tset); - if (retval) { - /* - * Remember on which subsystem the can_attach() - * failed, so that we only call cancel_attach() - * against the subsystems whose can_attach() - * succeeded. (See below) - */ - failed_ss = ss; - goto out; - } - } - } - - newcg = find_css_set(tsk->cgroups, cgrp); - if (!newcg) { - retval = -ENOMEM; - goto out; - } - - cgroup_task_migrate(cgrp, oldcgrp, tsk, newcg); - - for_each_subsys(root, ss) { - if (ss->attach) - ss->attach(cgrp, &tset); - } - -out: - if (retval) { - for_each_subsys(root, ss) { - if (ss == failed_ss) - /* - * This subsystem was the one that failed the - * can_attach() check earlier, so we don't need - * to call cancel_attach() against it or any - * remaining subsystems. - */ - break; - if (ss->cancel_attach) - ss->cancel_attach(cgrp, &tset); - } - } - return retval; -} - -/** * cgroup_attach_task_all - attach task 'tsk' to all cgroups of task 'from' * @from: attach to all cgroups of a given task * @tsk: the task to be attached @@ -2033,7 +1957,7 @@ int cgroup_attach_task_all(struct task_struct *from, struct task_struct *tsk) for_each_active_root(root) { struct cgroup *from_cg = task_cgroup_from_root(from, root); - retval = cgroup_attach_task(from_cg, tsk); + retval = cgroup_attach_task(from_cg, tsk, false); if (retval) break; } @@ -2044,21 +1968,22 @@ int cgroup_attach_task_all(struct task_struct *from, struct task_struct *tsk) EXPORT_SYMBOL_GPL(cgroup_attach_task_all); /** - * cgroup_attach_proc - attach all threads in a threadgroup to a cgroup + * cgroup_attach_task - attach a task or a whole threadgroup to a cgroup * @cgrp: the cgroup to attach to - * @leader: the threadgroup leader task_struct of the group to be attached + * @tsk: the task or the leader of the threadgroup to be attached + * @threadgroup: attach the whole threadgroup? * * Call holding cgroup_mutex and the group_rwsem of the leader. Will take - * task_lock of each thread in leader's threadgroup individually in turn. + * task_lock of @tsk or each thread in the threadgroup individually in turn. */ -static int cgroup_attach_proc(struct cgroup *cgrp, struct task_struct *leader) +int cgroup_attach_task(struct cgroup *cgrp, struct task_struct *tsk, + bool threadgroup) { int retval, i, group_size; struct cgroup_subsys *ss, *failed_ss = NULL; - /* guaranteed to be initialized later, but the compiler needs this */ struct cgroupfs_root *root = cgrp->root; /* threadgroup list cursor and array */ - struct task_struct *tsk; + struct task_struct *leader = tsk; struct task_and_cgroup *tc; struct flex_array *group; struct cgroup_taskset tset = { }; @@ -2070,7 +1995,10 @@ static int cgroup_attach_proc(struct cgroup *cgrp, struct task_struct *leader) * group - group_rwsem prevents new threads from appearing, and if * threads exit, this will just be an over-estimate. */ - group_size = get_nr_threads(leader); + if (threadgroup) + group_size = get_nr_threads(tsk); + else + group_size = 1; /* flex_array supports very large thread-groups better than kmalloc. */ group = flex_array_alloc(sizeof(*tc), group_size, GFP_KERNEL); if (!group) @@ -2080,7 +2008,6 @@ static int cgroup_attach_proc(struct cgroup *cgrp, struct task_struct *leader) if (retval) goto out_free_group_list; - tsk = leader; i = 0; /* * Prevent freeing of tasks while we take a snapshot. Tasks that are @@ -2109,6 +2036,9 @@ static int cgroup_attach_proc(struct cgroup *cgrp, struct task_struct *leader) retval = flex_array_put(group, i, &ent, GFP_ATOMIC); BUG_ON(retval != 0); i++; + + if (!threadgroup) + break; } while_each_thread(leader, tsk); rcu_read_unlock(); /* remember the number of threads in the array for later. */ @@ -2262,9 +2192,10 @@ retry_find_task: put_task_struct(tsk); goto retry_find_task; } - ret = cgroup_attach_proc(cgrp, tsk); - } else - ret = cgroup_attach_task(cgrp, tsk); + } + + ret = cgroup_attach_task(cgrp, tsk, threadgroup); + threadgroup_unlock(tsk); put_task_struct(tsk); diff --git a/kernel/cpuset.c b/kernel/cpuset.c index efbfca7a33e4..98d458aad789 100644 --- a/kernel/cpuset.c +++ b/kernel/cpuset.c @@ -2008,7 +2008,7 @@ static void cpuset_do_move_task(struct task_struct *tsk, struct cgroup *new_cgroup = scan->data; cgroup_lock(); - cgroup_attach_task(new_cgroup, tsk); + cgroup_attach_task(new_cgroup, tsk, false); cgroup_unlock(); } |