diff options
| -rw-r--r-- | include/linux/cgroup_subsys.h | 6 | ||||
| -rw-r--r-- | init/Kconfig | 10 | ||||
| -rw-r--r-- | kernel/sched.c | 121 |
3 files changed, 137 insertions, 0 deletions
diff --git a/include/linux/cgroup_subsys.h b/include/linux/cgroup_subsys.h index 651ff0869b2..0b9bfbde816 100644 --- a/include/linux/cgroup_subsys.h +++ b/include/linux/cgroup_subsys.h @@ -30,3 +30,9 @@ SUBSYS(ns) #endif /* */ + +#ifdef CONFIG_FAIR_CGROUP_SCHED +SUBSYS(cpu_cgroup) +#endif + +/* */ diff --git a/init/Kconfig b/init/Kconfig index 0007d1b5e86..541382d539a 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -334,6 +334,16 @@ config FAIR_USER_SCHED This option will choose userid as the basis for grouping tasks, thus providing equal CPU bandwidth to each user. +config FAIR_CGROUP_SCHED + bool "Control groups" + depends on CGROUPS + help + This option allows you to create arbitrary task groups + using the "cgroup" pseudo filesystem and control + the cpu bandwidth allocated to each such task group. + Refer to Documentation/cgroups.txt for more information + on "cgroup" pseudo filesystem. + endchoice config SYSFS_DEPRECATED diff --git a/kernel/sched.c b/kernel/sched.c index 4071306e108..afe76ec2e7f 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -155,10 +155,15 @@ struct rt_prio_array { #ifdef CONFIG_FAIR_GROUP_SCHED +#include <linux/cgroup.h> + struct cfs_rq; /* task group related information */ struct task_group { +#ifdef CONFIG_FAIR_CGROUP_SCHED + struct cgroup_subsys_state css; +#endif /* schedulable entities of this group on each cpu */ struct sched_entity **se; /* runqueue "owned" by this group on each cpu */ @@ -199,6 +204,9 @@ static inline struct task_group *task_group(struct task_struct *p) #ifdef CONFIG_FAIR_USER_SCHED tg = p->user->tg; +#elif defined(CONFIG_FAIR_CGROUP_SCHED) + tg = container_of(task_subsys_state(p, cpu_cgroup_subsys_id), + struct task_group, css); #else tg = &init_task_group; #endif @@ -7091,3 +7099,116 @@ unsigned long sched_group_shares(struct task_group *tg) } #endif /* CONFIG_FAIR_GROUP_SCHED */ + +#ifdef CONFIG_FAIR_CGROUP_SCHED + +/* return corresponding task_group object of a cgroup */ +static inline struct task_group *cgroup_tg(struct cgroup *cont) +{ + return container_of(cgroup_subsys_state(cont, cpu_cgroup_subsys_id), + struct task_group, css); +} + +static struct cgroup_subsys_state * +cpu_cgroup_create(struct cgroup_subsys *ss, struct cgroup *cont) +{ + struct task_group *tg; + + if (!cont->parent) { + /* This is early initialization for the top cgroup */ + init_task_group.css.cgroup = cont; + return &init_task_group.css; + } + + /* we support only 1-level deep hierarchical scheduler atm */ + if (cont->parent->parent) + return ERR_PTR(-EINVAL); + + tg = sched_create_group(); + if (IS_ERR(tg)) + return ERR_PTR(-ENOMEM); + + /* Bind the cgroup to task_group object we just created */ + tg->css.cgroup = cont; + + return &tg->css; +} + +static void cpu_cgroup_destroy(struct cgroup_subsys *ss, + struct cgroup *cont) +{ + struct task_group *tg = cgroup_tg(cont); + + sched_destroy_group(tg); +} + +static int cpu_cgroup_can_attach(struct cgroup_subsys *ss, + struct cgroup *cont, struct task_struct *tsk) +{ + /* We don't support RT-tasks being in separate groups */ + if (tsk->sched_class != &fair_sched_class) + return -EINVAL; + + return 0; +} + +static void +cpu_cgroup_attach(struct cgroup_subsys *ss, struct cgroup *cont, + struct cgroup *old_cont, struct task_struct *tsk) +{ + sched_move_task(tsk); +} + +static ssize_t cpu_shares_write(struct cgroup *cont, struct cftype *cftype, + struct file *file, const char __user *userbuf, + size_t nbytes, loff_t *ppos) +{ + unsigned long shareval; + struct task_group *tg = cgroup_tg(cont); + char buffer[2*sizeof(unsigned long) + 1]; + int rc; + + if (nbytes > 2*sizeof(unsigned long)) /* safety check */ + return -E2BIG; + + if (copy_from_user(buffer, userbuf, nbytes)) + return -EFAULT; + + buffer[nbytes] = 0; /* nul-terminate */ + shareval = simple_strtoul(buffer, NULL, 10); + + rc = sched_group_set_shares(tg, shareval); + + return (rc < 0 ? rc : nbytes); +} + +static u64 cpu_shares_read_uint(struct cgroup *cont, struct cftype *cft) +{ + struct task_group *tg = cgroup_tg(cont); + + return (u64) tg->shares; +} + +static struct cftype cpu_shares = { + .name = "shares", + .read_uint = cpu_shares_read_uint, + .write = cpu_shares_write, +}; + +static int cpu_cgroup_populate(struct cgroup_subsys *ss, struct cgroup *cont) +{ + return cgroup_add_file(cont, ss, &cpu_shares); +} + +struct cgroup_subsys cpu_cgroup_subsys = { + .name = "cpu", + .create = cpu_cgroup_create, + .destroy = cpu_cgroup_destroy, + .can_attach = cpu_cgroup_can_attach, + .attach = cpu_cgroup_attach, + .populate = cpu_cgroup_populate, + .subsys_id = cpu_cgroup_subsys_id, + .early_init = 1, +}; + +#endif /* CONFIG_FAIR_CGROUP_SCHED */ |