Merge branch 'linus' into sched/core

[pandora-kernel.git] / kernel / cpuset.c

diff --git a/kernel/cpuset.c b/kernel/cpuset.c
index b81f7f0..d247381 100644 (file)
--- 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_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)
+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);