From ec7dc8ac73e4a56ed03b673f026f08c0d547f597 Mon Sep 17 00:00:00 2001 From: Dhaval Giani Date: Sat, 19 Apr 2008 19:44:59 +0200 Subject: [PATCH] sched: allow the group scheduler to have multiple levels This patch makes the group scheduler multi hierarchy aware. [a.p.zijlstra@chello.nl: rt-parts and assorted fixes] Signed-off-by: Dhaval Giani Signed-off-by: Peter Zijlstra Signed-off-by: Ingo Molnar --- include/linux/sched.h | 2 +- kernel/sched.c | 85 +++++++++++++++++++++++++++---------------- kernel/user.c | 2 +- 3 files changed, 55 insertions(+), 34 deletions(-) diff --git a/include/linux/sched.h b/include/linux/sched.h index 79c025c3b62..fa14781747c 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -2052,7 +2052,7 @@ extern void normalize_rt_tasks(void); extern struct task_group init_task_group; -extern struct task_group *sched_create_group(void); +extern struct task_group *sched_create_group(struct task_group *parent); extern void sched_destroy_group(struct task_group *tg); extern void sched_move_task(struct task_struct *tsk); #ifdef CONFIG_FAIR_GROUP_SCHED diff --git a/kernel/sched.c b/kernel/sched.c index 1b7399dfa36..f9c8da798bb 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -7438,10 +7438,11 @@ static void init_rt_rq(struct rt_rq *rt_rq, struct rq *rq) } #ifdef CONFIG_FAIR_GROUP_SCHED -static void init_tg_cfs_entry(struct rq *rq, struct task_group *tg, - struct cfs_rq *cfs_rq, struct sched_entity *se, - int cpu, int add) +static void init_tg_cfs_entry(struct task_group *tg, struct cfs_rq *cfs_rq, + struct sched_entity *se, int cpu, int add, + struct sched_entity *parent) { + struct rq *rq = cpu_rq(cpu); tg->cfs_rq[cpu] = cfs_rq; init_cfs_rq(cfs_rq, rq); cfs_rq->tg = tg; @@ -7453,19 +7454,25 @@ static void init_tg_cfs_entry(struct rq *rq, struct task_group *tg, if (!se) return; - se->cfs_rq = &rq->cfs; + if (!parent) + se->cfs_rq = &rq->cfs; + else + se->cfs_rq = parent->my_q; + se->my_q = cfs_rq; se->load.weight = tg->shares; se->load.inv_weight = div64_64(1ULL<<32, se->load.weight); - se->parent = NULL; + se->parent = parent; } #endif #ifdef CONFIG_RT_GROUP_SCHED -static void init_tg_rt_entry(struct rq *rq, struct task_group *tg, - struct rt_rq *rt_rq, struct sched_rt_entity *rt_se, - int cpu, int add) +static void init_tg_rt_entry(struct task_group *tg, struct rt_rq *rt_rq, + struct sched_rt_entity *rt_se, int cpu, int add, + struct sched_rt_entity *parent) { + struct rq *rq = cpu_rq(cpu); + tg->rt_rq[cpu] = rt_rq; init_rt_rq(rt_rq, rq); rt_rq->tg = tg; @@ -7478,9 +7485,14 @@ static void init_tg_rt_entry(struct rq *rq, struct task_group *tg, if (!rt_se) return; + if (!parent) + rt_se->rt_rq = &rq->rt; + else + rt_se->rt_rq = parent->my_q; + rt_se->rt_rq = &rq->rt; rt_se->my_q = rt_rq; - rt_se->parent = NULL; + rt_se->parent = parent; INIT_LIST_HEAD(&rt_se->run_list); } #endif @@ -7568,7 +7580,7 @@ void __init sched_init(void) * We achieve this by letting init_task_group's tasks sit * directly in rq->cfs (i.e init_task_group->se[] = NULL). */ - init_tg_cfs_entry(rq, &init_task_group, &rq->cfs, NULL, i, 1); + init_tg_cfs_entry(&init_task_group, &rq->cfs, NULL, i, 1, NULL); #elif defined CONFIG_USER_SCHED /* * In case of task-groups formed thr' the user id of tasks, @@ -7581,9 +7593,9 @@ void __init sched_init(void) * (init_cfs_rq) and having one entity represent this group of * tasks in rq->cfs (i.e init_task_group->se[] != NULL). */ - init_tg_cfs_entry(rq, &init_task_group, + init_tg_cfs_entry(&init_task_group, &per_cpu(init_cfs_rq, i), - &per_cpu(init_sched_entity, i), i, 1); + &per_cpu(init_sched_entity, i), i, 1, NULL); #endif #endif /* CONFIG_FAIR_GROUP_SCHED */ @@ -7592,11 +7604,11 @@ void __init sched_init(void) #ifdef CONFIG_RT_GROUP_SCHED INIT_LIST_HEAD(&rq->leaf_rt_rq_list); #ifdef CONFIG_CGROUP_SCHED - init_tg_rt_entry(rq, &init_task_group, &rq->rt, NULL, i, 1); + init_tg_rt_entry(&init_task_group, &rq->rt, NULL, i, 1, NULL); #elif defined CONFIG_USER_SCHED - init_tg_rt_entry(rq, &init_task_group, + init_tg_rt_entry(&init_task_group, &per_cpu(init_rt_rq, i), - &per_cpu(init_sched_rt_entity, i), i, 1); + &per_cpu(init_sched_rt_entity, i), i, 1, NULL); #endif #endif @@ -7798,10 +7810,11 @@ static void free_fair_sched_group(struct task_group *tg) kfree(tg->se); } -static int alloc_fair_sched_group(struct task_group *tg) +static +int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent) { struct cfs_rq *cfs_rq; - struct sched_entity *se; + struct sched_entity *se, *parent_se; struct rq *rq; int i; @@ -7827,7 +7840,8 @@ static int alloc_fair_sched_group(struct task_group *tg) if (!se) goto err; - init_tg_cfs_entry(rq, tg, cfs_rq, se, i, 0); + parent_se = parent ? parent->se[i] : NULL; + init_tg_cfs_entry(tg, cfs_rq, se, i, 0, parent_se); } return 1; @@ -7851,7 +7865,8 @@ static inline void free_fair_sched_group(struct task_group *tg) { } -static inline int alloc_fair_sched_group(struct task_group *tg) +static inline +int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent) { return 1; } @@ -7883,10 +7898,11 @@ static void free_rt_sched_group(struct task_group *tg) kfree(tg->rt_se); } -static int alloc_rt_sched_group(struct task_group *tg) +static +int alloc_rt_sched_group(struct task_group *tg, struct task_group *parent) { struct rt_rq *rt_rq; - struct sched_rt_entity *rt_se; + struct sched_rt_entity *rt_se, *parent_se; struct rq *rq; int i; @@ -7913,7 +7929,8 @@ static int alloc_rt_sched_group(struct task_group *tg) if (!rt_se) goto err; - init_tg_rt_entry(rq, tg, rt_rq, rt_se, i, 0); + parent_se = parent ? parent->rt_se[i] : NULL; + init_tg_rt_entry(tg, rt_rq, rt_se, i, 0, parent_se); } return 1; @@ -7937,7 +7954,8 @@ static inline void free_rt_sched_group(struct task_group *tg) { } -static inline int alloc_rt_sched_group(struct task_group *tg) +static inline +int alloc_rt_sched_group(struct task_group *tg, struct task_group *parent) { return 1; } @@ -7960,7 +7978,7 @@ static void free_sched_group(struct task_group *tg) } /* allocate runqueue etc for a new task group */ -struct task_group *sched_create_group(void) +struct task_group *sched_create_group(struct task_group *parent) { struct task_group *tg; unsigned long flags; @@ -7970,10 +7988,10 @@ struct task_group *sched_create_group(void) if (!tg) return ERR_PTR(-ENOMEM); - if (!alloc_fair_sched_group(tg)) + if (!alloc_fair_sched_group(tg, parent)) goto err; - if (!alloc_rt_sched_group(tg)) + if (!alloc_rt_sched_group(tg, parent)) goto err; spin_lock_irqsave(&task_group_lock, flags); @@ -8084,6 +8102,12 @@ int sched_group_set_shares(struct task_group *tg, unsigned long shares) int i; unsigned long flags; + /* + * We can't change the weight of the root cgroup. + */ + if (!tg->se[0]) + return -EINVAL; + /* * A weight of 0 or 1 can cause arithmetics problems. * (The default weight is 1024 - so there's no practical @@ -8327,7 +8351,7 @@ static inline struct task_group *cgroup_tg(struct cgroup *cgrp) static struct cgroup_subsys_state * cpu_cgroup_create(struct cgroup_subsys *ss, struct cgroup *cgrp) { - struct task_group *tg; + struct task_group *tg, *parent; if (!cgrp->parent) { /* This is early initialization for the top cgroup */ @@ -8335,11 +8359,8 @@ cpu_cgroup_create(struct cgroup_subsys *ss, struct cgroup *cgrp) return &init_task_group.css; } - /* we support only 1-level deep hierarchical scheduler atm */ - if (cgrp->parent->parent) - return ERR_PTR(-EINVAL); - - tg = sched_create_group(); + parent = cgroup_tg(cgrp->parent); + tg = sched_create_group(parent); if (IS_ERR(tg)) return ERR_PTR(-ENOMEM); diff --git a/kernel/user.c b/kernel/user.c index 5925c6887c1..a28d9f99246 100644 --- a/kernel/user.c +++ b/kernel/user.c @@ -101,7 +101,7 @@ static int sched_create_user(struct user_struct *up) { int rc = 0; - up->tg = sched_create_group(); + up->tg = sched_create_group(NULL); if (IS_ERR(up->tg)) rc = -ENOMEM; -- 2.41.1