diff --git a/Documentation/cgroups/cgroups.txt b/Documentation/cgroups/cgroups.txt index 4bccfc19196..455d4e6d346 100644 --- a/Documentation/cgroups/cgroups.txt +++ b/Documentation/cgroups/cgroups.txt @@ -521,7 +521,7 @@ rmdir() will fail with it. From this behavior, pre_destroy() can be called multiple times against a cgroup. int can_attach(struct cgroup_subsys *ss, struct cgroup *cgrp, - struct task_struct *task) + struct task_struct *task, bool threadgroup) (cgroup_mutex held by caller) Called prior to moving a task into a cgroup; if the subsystem @@ -529,14 +529,20 @@ returns an error, this will abort the attach operation. If a NULL task is passed, then a successful result indicates that *any* unspecified task can be moved into the cgroup. Note that this isn't called on a fork. If this method returns 0 (success) then this should -remain valid while the caller holds cgroup_mutex. +remain valid while the caller holds cgroup_mutex. If threadgroup is +true, then a successful result indicates that all threads in the given +thread's threadgroup can be moved together. void attach(struct cgroup_subsys *ss, struct cgroup *cgrp, - struct cgroup *old_cgrp, struct task_struct *task) + struct cgroup *old_cgrp, struct task_struct *task, + bool threadgroup) (cgroup_mutex held by caller) Called after the task has been attached to the cgroup, to allow any post-attachment activity that requires memory allocations or blocking. +If threadgroup is true, the subsystem should take care of all threads +in the specified thread's threadgroup. Currently does not support any +subsystem that might need the old_cgrp for every thread in the group. void fork(struct cgroup_subsy *ss, struct task_struct *task) diff --git a/include/linux/cgroup.h b/include/linux/cgroup.h index 3ac78a2f4b5..b62bb9294d0 100644 --- a/include/linux/cgroup.h +++ b/include/linux/cgroup.h @@ -425,10 +425,11 @@ struct cgroup_subsys { struct cgroup *cgrp); int (*pre_destroy)(struct cgroup_subsys *ss, struct cgroup *cgrp); void (*destroy)(struct cgroup_subsys *ss, struct cgroup *cgrp); - int (*can_attach)(struct cgroup_subsys *ss, - struct cgroup *cgrp, struct task_struct *tsk); + int (*can_attach)(struct cgroup_subsys *ss, struct cgroup *cgrp, + struct task_struct *tsk, bool threadgroup); void (*attach)(struct cgroup_subsys *ss, struct cgroup *cgrp, - struct cgroup *old_cgrp, struct task_struct *tsk); + struct cgroup *old_cgrp, struct task_struct *tsk, + bool threadgroup); void (*fork)(struct cgroup_subsys *ss, struct task_struct *task); void (*exit)(struct cgroup_subsys *ss, struct task_struct *task); int (*populate)(struct cgroup_subsys *ss, diff --git a/kernel/cgroup.c b/kernel/cgroup.c index bf8dd1a9f2d..7ccba4bc5e3 100644 --- a/kernel/cgroup.c +++ b/kernel/cgroup.c @@ -1552,7 +1552,7 @@ int cgroup_attach_task(struct cgroup *cgrp, struct task_struct *tsk) for_each_subsys(root, ss) { if (ss->can_attach) { - retval = ss->can_attach(ss, cgrp, tsk); + retval = ss->can_attach(ss, cgrp, tsk, false); if (retval) return retval; } @@ -1590,7 +1590,7 @@ int cgroup_attach_task(struct cgroup *cgrp, struct task_struct *tsk) for_each_subsys(root, ss) { if (ss->attach) - ss->attach(ss, cgrp, oldcgrp, tsk); + ss->attach(ss, cgrp, oldcgrp, tsk, false); } set_bit(CGRP_RELEASABLE, &oldcgrp->flags); synchronize_rcu(); diff --git a/kernel/cgroup_freezer.c b/kernel/cgroup_freezer.c index fb249e2bcad..59e9ef6aab4 100644 --- a/kernel/cgroup_freezer.c +++ b/kernel/cgroup_freezer.c @@ -159,7 +159,7 @@ static bool is_task_frozen_enough(struct task_struct *task) */ static int freezer_can_attach(struct cgroup_subsys *ss, struct cgroup *new_cgroup, - struct task_struct *task) + struct task_struct *task, bool threadgroup) { struct freezer *freezer; @@ -177,6 +177,19 @@ static int freezer_can_attach(struct cgroup_subsys *ss, if (freezer->state == CGROUP_FROZEN) return -EBUSY; + if (threadgroup) { + struct task_struct *c; + + rcu_read_lock(); + list_for_each_entry_rcu(c, &task->thread_group, thread_group) { + if (is_task_frozen_enough(c)) { + rcu_read_unlock(); + return -EBUSY; + } + } + rcu_read_unlock(); + } + return 0; } diff --git a/kernel/cpuset.c b/kernel/cpuset.c index 7e75a41bd50..b5cb469d254 100644 --- a/kernel/cpuset.c +++ b/kernel/cpuset.c @@ -1324,9 +1324,10 @@ static int fmeter_getrate(struct fmeter *fmp) static cpumask_var_t cpus_attach; /* Called by cgroups to determine if a cpuset is usable; cgroup_mutex held */ -static int cpuset_can_attach(struct cgroup_subsys *ss, - struct cgroup *cont, struct task_struct *tsk) +static int cpuset_can_attach(struct cgroup_subsys *ss, struct cgroup *cont, + struct task_struct *tsk, bool threadgroup) { + int ret; struct cpuset *cs = cgroup_cs(cont); if (cpumask_empty(cs->cpus_allowed) || nodes_empty(cs->mems_allowed)) @@ -1343,18 +1344,51 @@ static int cpuset_can_attach(struct cgroup_subsys *ss, if (tsk->flags & PF_THREAD_BOUND) return -EINVAL; - return security_task_setscheduler(tsk, 0, NULL); + ret = security_task_setscheduler(tsk, 0, NULL); + if (ret) + return ret; + if (threadgroup) { + struct task_struct *c; + + rcu_read_lock(); + list_for_each_entry_rcu(c, &tsk->thread_group, thread_group) { + ret = security_task_setscheduler(c, 0, NULL); + if (ret) { + rcu_read_unlock(); + return ret; + } + } + rcu_read_unlock(); + } + return 0; } -static void cpuset_attach(struct cgroup_subsys *ss, - struct cgroup *cont, struct cgroup *oldcont, - struct task_struct *tsk) +static void cpuset_attach_task(struct task_struct *tsk, nodemask_t *to, + struct cpuset *cs) +{ + int err; + /* + * can_attach beforehand should guarantee that this doesn't fail. + * TODO: have a better way to handle failure here + */ + err = set_cpus_allowed_ptr(tsk, cpus_attach); + WARN_ON_ONCE(err); + + task_lock(tsk); + cpuset_change_task_nodemask(tsk, to); + task_unlock(tsk); + cpuset_update_task_spread_flag(cs, tsk); + +} + +static void cpuset_attach(struct cgroup_subsys *ss, struct cgroup *cont, + struct cgroup *oldcont, struct task_struct *tsk, + bool threadgroup) { nodemask_t from, to; struct mm_struct *mm; struct cpuset *cs = cgroup_cs(cont); struct cpuset *oldcs = cgroup_cs(oldcont); - int err; if (cs == &top_cpuset) { cpumask_copy(cpus_attach, cpu_possible_mask); @@ -1363,15 +1397,19 @@ static void cpuset_attach(struct cgroup_subsys *ss, guarantee_online_cpus(cs, cpus_attach); guarantee_online_mems(cs, &to); } - err = set_cpus_allowed_ptr(tsk, cpus_attach); - if (err) - return; - task_lock(tsk); - cpuset_change_task_nodemask(tsk, &to); - task_unlock(tsk); - cpuset_update_task_spread_flag(cs, tsk); + /* do per-task migration stuff possibly for each in the threadgroup */ + cpuset_attach_task(tsk, &to, cs); + if (threadgroup) { + struct task_struct *c; + rcu_read_lock(); + list_for_each_entry_rcu(c, &tsk->thread_group, thread_group) { + cpuset_attach_task(c, &to, cs); + } + rcu_read_unlock(); + } + /* change mm; only needs to be done once even if threadgroup */ from = oldcs->mems_allowed; to = cs->mems_allowed; mm = get_task_mm(tsk); diff --git a/kernel/ns_cgroup.c b/kernel/ns_cgroup.c index 5aa854f9e5a..2a5dfec8efe 100644 --- a/kernel/ns_cgroup.c +++ b/kernel/ns_cgroup.c @@ -42,8 +42,8 @@ int ns_cgroup_clone(struct task_struct *task, struct pid *pid) * (hence either you are in the same cgroup as task, or in an * ancestor cgroup thereof) */ -static int ns_can_attach(struct cgroup_subsys *ss, - struct cgroup *new_cgroup, struct task_struct *task) +static int ns_can_attach(struct cgroup_subsys *ss, struct cgroup *new_cgroup, + struct task_struct *task, bool threadgroup) { if (current != task) { if (!capable(CAP_SYS_ADMIN)) @@ -56,6 +56,18 @@ static int ns_can_attach(struct cgroup_subsys *ss, if (!cgroup_is_descendant(new_cgroup, task)) return -EPERM; + if (threadgroup) { + struct task_struct *c; + rcu_read_lock(); + list_for_each_entry_rcu(c, &task->thread_group, thread_group) { + if (!cgroup_is_descendant(new_cgroup, c)) { + rcu_read_unlock(); + return -EPERM; + } + } + rcu_read_unlock(); + } + return 0; } diff --git a/kernel/sched.c b/kernel/sched.c index 2f76e06bea5..0d0361b9dbb 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -10377,8 +10377,7 @@ cpu_cgroup_destroy(struct cgroup_subsys *ss, struct cgroup *cgrp) } static int -cpu_cgroup_can_attach(struct cgroup_subsys *ss, struct cgroup *cgrp, - struct task_struct *tsk) +cpu_cgroup_can_attach_task(struct cgroup *cgrp, struct task_struct *tsk) { #ifdef CONFIG_RT_GROUP_SCHED if (!sched_rt_can_attach(cgroup_tg(cgrp), tsk)) @@ -10388,15 +10387,45 @@ cpu_cgroup_can_attach(struct cgroup_subsys *ss, struct cgroup *cgrp, if (tsk->sched_class != &fair_sched_class) return -EINVAL; #endif + return 0; +} +static int +cpu_cgroup_can_attach(struct cgroup_subsys *ss, struct cgroup *cgrp, + struct task_struct *tsk, bool threadgroup) +{ + int retval = cpu_cgroup_can_attach_task(cgrp, tsk); + if (retval) + return retval; + if (threadgroup) { + struct task_struct *c; + rcu_read_lock(); + list_for_each_entry_rcu(c, &tsk->thread_group, thread_group) { + retval = cpu_cgroup_can_attach_task(cgrp, c); + if (retval) { + rcu_read_unlock(); + return retval; + } + } + rcu_read_unlock(); + } return 0; } static void cpu_cgroup_attach(struct cgroup_subsys *ss, struct cgroup *cgrp, - struct cgroup *old_cont, struct task_struct *tsk) + struct cgroup *old_cont, struct task_struct *tsk, + bool threadgroup) { sched_move_task(tsk); + if (threadgroup) { + struct task_struct *c; + rcu_read_lock(); + list_for_each_entry_rcu(c, &tsk->thread_group, thread_group) { + sched_move_task(c); + } + rcu_read_unlock(); + } } #ifdef CONFIG_FAIR_GROUP_SCHED diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 9b10d875378..cf2e717f5c1 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -2612,7 +2612,8 @@ static int mem_cgroup_populate(struct cgroup_subsys *ss, static void mem_cgroup_move_task(struct cgroup_subsys *ss, struct cgroup *cont, struct cgroup *old_cont, - struct task_struct *p) + struct task_struct *p, + bool threadgroup) { mutex_lock(&memcg_tasklist); /* diff --git a/security/device_cgroup.c b/security/device_cgroup.c index b8186bac8b7..6cf8fd2b79e 100644 --- a/security/device_cgroup.c +++ b/security/device_cgroup.c @@ -61,7 +61,8 @@ static inline struct dev_cgroup *task_devcgroup(struct task_struct *task) struct cgroup_subsys devices_subsys; static int devcgroup_can_attach(struct cgroup_subsys *ss, - struct cgroup *new_cgroup, struct task_struct *task) + struct cgroup *new_cgroup, struct task_struct *task, + bool threadgroup) { if (current != task && !capable(CAP_SYS_ADMIN)) return -EPERM;