X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=kernel%2Fsched.c;h=67d9d1799d864ef8e6680ce4c07deae68f5beb8a;hb=43af66e1359999e3a6e306d4ee6edfc6c7d26595;hp=3f6bd1112900c9bcf5151d25a22b1d3d8dfda29c;hpb=71d00feca2598c68186ca5b83247746d6a7fed7e;p=linux-2.6 diff --git a/kernel/sched.c b/kernel/sched.c index 3f6bd11129..67d9d1799d 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -52,7 +52,6 @@ #include #include #include -#include #include #include #include @@ -75,7 +74,7 @@ */ unsigned long long __attribute__((weak)) sched_clock(void) { - return (unsigned long long)jiffies * (1000000000 / HZ); + return (unsigned long long)jiffies * (NSEC_PER_SEC / HZ); } /* @@ -99,8 +98,8 @@ unsigned long long __attribute__((weak)) sched_clock(void) /* * Some helpers for converting nanosecond timing to jiffy resolution */ -#define NS_TO_JIFFIES(TIME) ((unsigned long)(TIME) / (1000000000 / HZ)) -#define JIFFIES_TO_NS(TIME) ((TIME) * (1000000000 / HZ)) +#define NS_TO_JIFFIES(TIME) ((unsigned long)(TIME) / (NSEC_PER_SEC / HZ)) +#define JIFFIES_TO_NS(TIME) ((TIME) * (NSEC_PER_SEC / HZ)) #define NICE_0_LOAD SCHED_LOAD_SCALE #define NICE_0_SHIFT SCHED_LOAD_SHIFT @@ -210,22 +209,21 @@ static inline struct task_group *task_group(struct task_struct *p) tg = container_of(task_subsys_state(p, cpu_cgroup_subsys_id), struct task_group, css); #else - tg = &init_task_group; + tg = &init_task_group; #endif - return tg; } /* Change a task's cfs_rq and parent entity if it moves across CPUs/groups */ -static inline void set_task_cfs_rq(struct task_struct *p) +static inline void set_task_cfs_rq(struct task_struct *p, unsigned int cpu) { - p->se.cfs_rq = task_group(p)->cfs_rq[task_cpu(p)]; - p->se.parent = task_group(p)->se[task_cpu(p)]; + p->se.cfs_rq = task_group(p)->cfs_rq[cpu]; + p->se.parent = task_group(p)->se[cpu]; } #else -static inline void set_task_cfs_rq(struct task_struct *p) { } +static inline void set_task_cfs_rq(struct task_struct *p, unsigned int cpu) { } #endif /* CONFIG_FAIR_GROUP_SCHED */ @@ -250,15 +248,16 @@ struct cfs_rq { #ifdef CONFIG_FAIR_GROUP_SCHED struct rq *rq; /* cpu runqueue to which this cfs_rq is attached */ - /* leaf cfs_rqs are those that hold tasks (lowest schedulable entity in + /* + * leaf cfs_rqs are those that hold tasks (lowest schedulable entity in * a hierarchy). Non-leaf lrqs hold other higher schedulable entities * (like users, containers etc.) * * leaf_cfs_rq_list ties together list of leaf cfs_rq's in a cpu. This * list is used during load balance. */ - struct list_head leaf_cfs_rq_list; /* Better name : task_cfs_rq_list? */ - struct task_group *tg; /* group that "owns" this runqueue */ + struct list_head leaf_cfs_rq_list; + struct task_group *tg; /* group that "owns" this runqueue */ #endif }; @@ -301,7 +300,7 @@ struct rq { /* list of leaf cfs_rq on this cpu: */ struct list_head leaf_cfs_rq_list; #endif - struct rt_rq rt; + struct rt_rq rt; /* * This is part of a global counter where only the total sum @@ -456,23 +455,27 @@ static void update_rq_clock(struct rq *rq) */ enum { SCHED_FEAT_NEW_FAIR_SLEEPERS = 1, - SCHED_FEAT_START_DEBIT = 2, - SCHED_FEAT_TREE_AVG = 4, - SCHED_FEAT_APPROX_AVG = 8, - SCHED_FEAT_WAKEUP_PREEMPT = 16, - SCHED_FEAT_PREEMPT_RESTRICT = 32, + SCHED_FEAT_WAKEUP_PREEMPT = 2, + SCHED_FEAT_START_DEBIT = 4, + SCHED_FEAT_TREE_AVG = 8, + SCHED_FEAT_APPROX_AVG = 16, }; const_debug unsigned int sysctl_sched_features = SCHED_FEAT_NEW_FAIR_SLEEPERS * 1 | + SCHED_FEAT_WAKEUP_PREEMPT * 1 | SCHED_FEAT_START_DEBIT * 1 | SCHED_FEAT_TREE_AVG * 0 | - SCHED_FEAT_APPROX_AVG * 0 | - SCHED_FEAT_WAKEUP_PREEMPT * 1 | - SCHED_FEAT_PREEMPT_RESTRICT * 1; + SCHED_FEAT_APPROX_AVG * 0; #define sched_feat(x) (sysctl_sched_features & SCHED_FEAT_##x) +/* + * Number of tasks to iterate in a single balance run. + * Limited because this is done with IRQs disabled. + */ +const_debug unsigned int sysctl_sched_nr_migrate = 32; + /* * For kernel-internal use: high-speed (but slightly incorrect) per-cpu * clock constructed from sched_clock(): @@ -588,7 +591,7 @@ static inline struct rq *__task_rq_lock(struct task_struct *p) /* * task_rq_lock - lock the runqueue a given task resides on and disable - * interrupts. Note the ordering: we can safely lookup the task_rq without + * interrupts. Note the ordering: we can safely lookup the task_rq without * explicitly disabling preemption. */ static struct rq *task_rq_lock(struct task_struct *p, unsigned long *flags) @@ -776,7 +779,7 @@ static inline void update_load_sub(struct load_weight *lw, unsigned long dec) * To aid in avoiding the subversion of "niceness" due to uneven distribution * of tasks with abnormal "nice" values across CPUs the contribution that * each task makes to its run queue's load is weighted according to its - * scheduling class and "nice" value. For SCHED_NORMAL tasks this is just a + * scheduling class and "nice" value. For SCHED_NORMAL tasks this is just a * scaled version of the new time slice allocation that they receive on time * slice expiry etc. */ @@ -851,6 +854,12 @@ iter_move_one_task(struct rq *this_rq, int this_cpu, struct rq *busiest, struct rq_iterator *iterator); #endif +#ifdef CONFIG_CGROUP_CPUACCT +static void cpuacct_charge(struct task_struct *tsk, u64 cputime); +#else +static inline void cpuacct_charge(struct task_struct *tsk, u64 cputime) {} +#endif + #include "sched_stats.h" #include "sched_idletask.c" #include "sched_fair.c" @@ -1019,10 +1028,16 @@ unsigned long weighted_cpuload(const int cpu) static inline void __set_task_cpu(struct task_struct *p, unsigned int cpu) { + set_task_cfs_rq(p, cpu); #ifdef CONFIG_SMP + /* + * After ->cpu is set up to a new value, task_rq_lock(p, ...) can be + * successfuly executed on another CPU. We must ensure that updates of + * per-task data have been completed by this moment. + */ + smp_wmb(); task_thread_info(p)->cpu = cpu; #endif - set_task_cfs_rq(p); } #ifdef CONFIG_SMP @@ -1839,7 +1854,7 @@ prepare_task_switch(struct rq *rq, struct task_struct *prev, * and do any other architecture-specific cleanup actions. * * Note that we may have delayed dropping an mm in context_switch(). If - * so, we finish that here outside of the runqueue lock. (Doing it + * so, we finish that here outside of the runqueue lock. (Doing it * with the lock held can cause deadlocks; see schedule() for * details.) */ @@ -2121,7 +2136,7 @@ static void double_lock_balance(struct rq *this_rq, struct rq *busiest) /* * If dest_cpu is allowed for this process, migrate the task to it. * This is accomplished by forcing the cpu_allowed mask to only - * allow dest_cpu, which will force the cpu onto dest_cpu. Then + * allow dest_cpu, which will force the cpu onto dest_cpu. Then * the cpu_allowed mask is restored. */ static void sched_migrate_task(struct task_struct *p, int dest_cpu) @@ -2237,7 +2252,7 @@ balance_tasks(struct rq *this_rq, int this_cpu, struct rq *busiest, enum cpu_idle_type idle, int *all_pinned, int *this_best_prio, struct rq_iterator *iterator) { - int pulled = 0, pinned = 0, skip_for_load; + int loops = 0, pulled = 0, pinned = 0, skip_for_load; struct task_struct *p; long rem_load_move = max_load_move; @@ -2251,10 +2266,10 @@ balance_tasks(struct rq *this_rq, int this_cpu, struct rq *busiest, */ p = iterator->start(iterator->arg); next: - if (!p) + if (!p || loops++ > sysctl_sched_nr_migrate) goto out; /* - * To help distribute high priority tasks accross CPUs we don't + * To help distribute high priority tasks across CPUs we don't * skip a task if it will be the highest priority task (i.e. smallest * prio value) on its new queue regardless of its load weight */ @@ -2271,8 +2286,7 @@ next: rem_load_move -= p->se.load.weight; /* - * We only want to steal up to the prescribed number of tasks - * and the prescribed amount of weighted load. + * We only want to steal up to the prescribed amount of weighted load. */ if (rem_load_move > 0) { if (p->prio < *this_best_prio) @@ -2567,7 +2581,7 @@ group_next: * tasks around. Thus we look for the minimum possible imbalance. * Negative imbalances (*we* are more loaded than anyone else) will * be counted as no imbalance for these purposes -- we can't fix that - * by pulling tasks to us. Be careful of negative numbers as they'll + * by pulling tasks to us. Be careful of negative numbers as they'll * appear as very large values with unsigned longs. */ if (max_load <= busiest_load_per_task) @@ -3002,7 +3016,7 @@ static void active_load_balance(struct rq *busiest_rq, int busiest_cpu) /* * This condition is "impossible", if it occurs - * we need to fix it. Originally reported by + * we need to fix it. Originally reported by * Bjorn Helgaas on a 128-cpu setup. */ BUG_ON(busiest_rq == target_rq); @@ -3034,7 +3048,7 @@ static void active_load_balance(struct rq *busiest_rq, int busiest_cpu) #ifdef CONFIG_NO_HZ static struct { atomic_t load_balancer; - cpumask_t cpu_mask; + cpumask_t cpu_mask; } nohz ____cacheline_aligned = { .load_balancer = ATOMIC_INIT(-1), .cpu_mask = CPU_MASK_NONE, @@ -3335,13 +3349,9 @@ void account_user_time(struct task_struct *p, cputime_t cputime) { struct cpu_usage_stat *cpustat = &kstat_this_cpu.cpustat; cputime64_t tmp; - struct rq *rq = this_rq(); p->utime = cputime_add(p->utime, cputime); - if (p != rq->idle) - cpuacct_charge(p, cputime); - /* Add user time to cpustat. */ tmp = cputime_to_cputime64(cputime); if (TASK_NICE(p) > 0) @@ -3392,10 +3402,8 @@ void account_system_time(struct task_struct *p, int hardirq_offset, struct rq *rq = this_rq(); cputime64_t tmp; - if (p->flags & PF_VCPU) { - account_guest_time(p, cputime); - return; - } + if ((p->flags & PF_VCPU) && (irq_count() - hardirq_offset == 0)) + return account_guest_time(p, cputime); p->stime = cputime_add(p->stime, cputime); @@ -3405,10 +3413,9 @@ void account_system_time(struct task_struct *p, int hardirq_offset, cpustat->irq = cputime64_add(cpustat->irq, tmp); else if (softirq_count()) cpustat->softirq = cputime64_add(cpustat->softirq, tmp); - else if (p != rq->idle) { + else if (p != rq->idle) cpustat->system = cputime64_add(cpustat->system, tmp); - cpuacct_charge(p, cputime); - } else if (atomic_read(&rq->nr_iowait) > 0) + else if (atomic_read(&rq->nr_iowait) > 0) cpustat->iowait = cputime64_add(cpustat->iowait, tmp); else cpustat->idle = cputime64_add(cpustat->idle, tmp); @@ -3444,10 +3451,8 @@ void account_steal_time(struct task_struct *p, cputime_t steal) cpustat->iowait = cputime64_add(cpustat->iowait, tmp); else cpustat->idle = cputime64_add(cpustat->idle, tmp); - } else { + } else cpustat->steal = cputime64_add(cpustat->steal, tmp); - cpuacct_charge(p, -tmp); - } } /* @@ -3547,7 +3552,7 @@ static noinline void __schedule_bug(struct task_struct *prev) static inline void schedule_debug(struct task_struct *prev) { /* - * Test if we are atomic. Since do_exit() needs to call into + * Test if we are atomic. Since do_exit() needs to call into * schedule() atomically, we ignore that path for now. * Otherwise, whine if we are scheduling when we should not be. */ @@ -3669,7 +3674,7 @@ EXPORT_SYMBOL(schedule); #ifdef CONFIG_PREEMPT /* * this is the entry point to schedule() from in-kernel preemption - * off of preempt_enable. Kernel preemptions off return from interrupt + * off of preempt_enable. Kernel preemptions off return from interrupt * occur there and call schedule directly. */ asmlinkage void __sched preempt_schedule(void) @@ -3681,7 +3686,7 @@ asmlinkage void __sched preempt_schedule(void) #endif /* * If there is a non-zero preempt_count or interrupts are disabled, - * we do not want to preempt the current task. Just return.. + * we do not want to preempt the current task. Just return.. */ if (likely(ti->preempt_count || irqs_disabled())) return; @@ -3767,12 +3772,12 @@ int default_wake_function(wait_queue_t *curr, unsigned mode, int sync, EXPORT_SYMBOL(default_wake_function); /* - * The core wakeup function. Non-exclusive wakeups (nr_exclusive == 0) just - * wake everything up. If it's an exclusive wakeup (nr_exclusive == small +ve + * The core wakeup function. Non-exclusive wakeups (nr_exclusive == 0) just + * wake everything up. If it's an exclusive wakeup (nr_exclusive == small +ve * number) then we wake all the non-exclusive tasks and one exclusive task. * * There are circumstances in which we can try to wake a task which has already - * started to run but is not in state TASK_RUNNING. try_to_wake_up() returns + * started to run but is not in state TASK_RUNNING. try_to_wake_up() returns * zero in this (rare) case, and we handle it by continuing to scan the queue. */ static void __wake_up_common(wait_queue_head_t *q, unsigned int mode, @@ -4385,8 +4390,8 @@ do_sched_setscheduler(pid_t pid, int policy, struct sched_param __user *param) * @policy: new policy. * @param: structure containing the new RT priority. */ -asmlinkage long sys_sched_setscheduler(pid_t pid, int policy, - struct sched_param __user *param) +asmlinkage long +sys_sched_setscheduler(pid_t pid, int policy, struct sched_param __user *param) { /* negative values for policy are not valid */ if (policy < 0) @@ -4486,7 +4491,7 @@ long sched_setaffinity(pid_t pid, cpumask_t new_mask) /* * It is not safe to call set_cpus_allowed with the - * tasklist_lock held. We will bump the task_struct's + * tasklist_lock held. We will bump the task_struct's * usage count and then drop tasklist_lock. */ get_task_struct(p); @@ -4682,7 +4687,7 @@ EXPORT_SYMBOL(cond_resched); * cond_resched_lock() - if a reschedule is pending, drop the given lock, * call schedule, and on return reacquire the lock. * - * This works OK both with and without CONFIG_PREEMPT. We do strange low-level + * This works OK both with and without CONFIG_PREEMPT. We do strange low-level * operations here to prevent schedule() from being called twice (once via * spin_unlock(), once by hand). */ @@ -4736,7 +4741,7 @@ void __sched yield(void) EXPORT_SYMBOL(yield); /* - * This task is about to go to sleep on IO. Increment rq->nr_iowait so + * This task is about to go to sleep on IO. Increment rq->nr_iowait so * that process accounting knows that this is a task in IO wait state. * * But don't do that if it is a deliberate, throttling IO wait (this task @@ -4845,17 +4850,21 @@ long sys_sched_rr_get_interval(pid_t pid, struct timespec __user *interval) if (retval) goto out_unlock; - if (p->policy == SCHED_FIFO) - time_slice = 0; - else if (p->policy == SCHED_RR) + /* + * Time slice is 0 for SCHED_FIFO tasks and for SCHED_OTHER + * tasks that are on an otherwise idle runqueue: + */ + time_slice = 0; + if (p->policy == SCHED_RR) { time_slice = DEF_TIMESLICE; - else { + } else { struct sched_entity *se = &p->se; unsigned long flags; struct rq *rq; rq = task_rq_lock(p, &flags); - time_slice = NS_TO_JIFFIES(sched_slice(cfs_rq_of(se), se)); + if (rq->cfs.load.weight) + time_slice = NS_TO_JIFFIES(sched_slice(&rq->cfs, se)); task_rq_unlock(rq, &flags); } read_unlock(&tasklist_lock); @@ -4992,6 +5001,32 @@ void __cpuinit init_idle(struct task_struct *idle, int cpu) */ cpumask_t nohz_cpu_mask = CPU_MASK_NONE; +/* + * Increase the granularity value when there are more CPUs, + * because with more CPUs the 'effective latency' as visible + * to users decreases. But the relationship is not linear, + * so pick a second-best guess by going with the log2 of the + * number of CPUs. + * + * This idea comes from the SD scheduler of Con Kolivas: + */ +static inline void sched_init_granularity(void) +{ + unsigned int factor = 1 + ilog2(num_online_cpus()); + const unsigned long limit = 200000000; + + sysctl_sched_min_granularity *= factor; + if (sysctl_sched_min_granularity > limit) + sysctl_sched_min_granularity = limit; + + sysctl_sched_latency *= factor; + if (sysctl_sched_latency > limit) + sysctl_sched_latency = limit; + + sysctl_sched_wakeup_granularity *= factor; + sysctl_sched_batch_wakeup_granularity *= factor; +} + #ifdef CONFIG_SMP /* * This is how migration works: @@ -5015,7 +5050,7 @@ cpumask_t nohz_cpu_mask = CPU_MASK_NONE; * is removed from the allowed bitmask. * * NOTE: the caller must have a valid reference to the task, the - * task must not exit() & deallocate itself prematurely. The + * task must not exit() & deallocate itself prematurely. The * call is not atomic; no spinlocks may be held. */ int set_cpus_allowed(struct task_struct *p, cpumask_t new_mask) @@ -5052,7 +5087,7 @@ out: EXPORT_SYMBOL_GPL(set_cpus_allowed); /* - * Move (not current) task off this cpu, onto dest cpu. We're doing + * Move (not current) task off this cpu, onto dest cpu. We're doing * this because either it can't run here any more (set_cpus_allowed() * away from this CPU, or CPU going down), or because we're * attempting to rebalance this task on exec (sched_exec). @@ -5197,7 +5232,7 @@ static void move_task_off_dead_cpu(int dead_cpu, struct task_struct *p) * Try to stay on the same cpuset, where the * current cpuset may be a subset of all cpus. * The cpuset_cpus_allowed_locked() variant of - * cpuset_cpus_allowed() will not block. It must be + * cpuset_cpus_allowed() will not block. It must be * called within calls to cpuset_lock/cpuset_unlock. */ rq = task_rq_lock(p, &flags); @@ -5210,10 +5245,11 @@ static void move_task_off_dead_cpu(int dead_cpu, struct task_struct *p) * kernel threads (both mm NULL), since they never * leave kernel. */ - if (p->mm && printk_ratelimit()) + if (p->mm && printk_ratelimit()) { printk(KERN_INFO "process %d (%s) no " "longer affine to cpu%d\n", - task_pid_nr(p), p->comm, dead_cpu); + task_pid_nr(p), p->comm, dead_cpu); + } } } while (!__migrate_task_irq(p, dead_cpu, dest_cpu)); } @@ -5256,24 +5292,10 @@ static void migrate_live_tasks(int src_cpu) read_unlock(&tasklist_lock); } -/* - * activate_idle_task - move idle task to the _front_ of runqueue. - */ -static void activate_idle_task(struct task_struct *p, struct rq *rq) -{ - update_rq_clock(rq); - - if (p->state == TASK_UNINTERRUPTIBLE) - rq->nr_uninterruptible--; - - enqueue_task(rq, p, 0); - inc_nr_running(p, rq); -} - /* * Schedules idle task to be the next runnable task on current CPU. - * It does so by boosting its priority to highest possible and adding it to - * the _front_ of the runqueue. Used by CPU offline code. + * It does so by boosting its priority to highest possible. + * Used by CPU offline code. */ void sched_idle_next(void) { @@ -5293,8 +5315,8 @@ void sched_idle_next(void) __setscheduler(rq, p, SCHED_FIFO, MAX_RT_PRIO-1); - /* Add idle task to the _front_ of its priority queue: */ - activate_idle_task(p, rq); + update_rq_clock(rq); + activate_task(rq, p, 0); spin_unlock_irqrestore(&rq->lock, flags); } @@ -5329,7 +5351,7 @@ static void migrate_dead(unsigned int dead_cpu, struct task_struct *p) /* * Drop lock around migration; if someone else moves it, - * that's OK. No task can be added to this CPU, so iteration is + * that's OK. No task can be added to this CPU, so iteration is * fine. */ spin_unlock_irq(&rq->lock); @@ -5393,7 +5415,7 @@ static void sd_free_ctl_entry(struct ctl_table **tablep) /* * In the intermediate directories, both the child directory and * procname are dynamically allocated and could fail but the mode - * will always be set. In the lowest directory the names are + * will always be set. In the lowest directory the names are * static strings and all have proc handlers. */ for (entry = *tablep; entry->mode; entry++) { @@ -5455,7 +5477,7 @@ sd_alloc_ctl_domain_table(struct sched_domain *sd) return table; } -static ctl_table * sd_alloc_ctl_cpu_table(int cpu) +static ctl_table *sd_alloc_ctl_cpu_table(int cpu) { struct ctl_table *entry, *table; struct sched_domain *sd; @@ -5564,7 +5586,7 @@ migration_call(struct notifier_block *nfb, unsigned long action, void *hcpu) case CPU_UP_CANCELED_FROZEN: if (!cpu_rq(cpu)->migration_thread) break; - /* Unbind it from offline cpu so it can run. Fall thru. */ + /* Unbind it from offline cpu so it can run. Fall thru. */ kthread_bind(cpu_rq(cpu)->migration_thread, any_online_cpu(cpu_online_map)); kthread_stop(cpu_rq(cpu)->migration_thread); @@ -5591,9 +5613,11 @@ migration_call(struct notifier_block *nfb, unsigned long action, void *hcpu) migrate_nr_uninterruptible(rq); BUG_ON(rq->nr_running != 0); - /* No need to migrate the tasks: it was best-effort if - * they didn't take sched_hotcpu_mutex. Just wake up - * the requestors. */ + /* + * No need to migrate the tasks: it was best-effort if + * they didn't take sched_hotcpu_mutex. Just wake up + * the requestors. + */ spin_lock_irq(&rq->lock); while (!list_empty(&rq->migration_queue)) { struct migration_req *req; @@ -5621,7 +5645,7 @@ static struct notifier_block __cpuinitdata migration_notifier = { .priority = 10 }; -int __init migration_init(void) +void __init migration_init(void) { void *cpu = (void *)(long)smp_processor_id(); int err; @@ -5631,8 +5655,6 @@ int __init migration_init(void) BUG_ON(err == NOTIFY_BAD); migration_call(&migration_notifier, CPU_ONLINE, cpu); register_cpu_notifier(&migration_notifier); - - return 0; } #endif @@ -5903,7 +5925,7 @@ init_sched_build_groups(cpumask_t span, const cpumask_t *cpu_map, * @node: node whose sched_domain we're building * @used_nodes: nodes already in the sched_domain * - * Find the next node to include in a given scheduling domain. Simply + * Find the next node to include in a given scheduling domain. Simply * finds the closest node not already in the @used_nodes map. * * Should use nodemask_t. @@ -5943,7 +5965,7 @@ static int find_next_best_node(int node, unsigned long *used_nodes) * @node: node whose cpumask we're constructing * @size: number of nodes to include in this span * - * Given a node, construct a good cpumask for its sched_domain to span. It + * Given a node, construct a good cpumask for its sched_domain to span. It * should be one that prevents unnecessary balancing, but also spreads tasks * out optimally. */ @@ -5980,8 +6002,8 @@ int sched_smt_power_savings = 0, sched_mc_power_savings = 0; static DEFINE_PER_CPU(struct sched_domain, cpu_domains); static DEFINE_PER_CPU(struct sched_group, sched_group_cpus); -static int cpu_to_cpu_group(int cpu, const cpumask_t *cpu_map, - struct sched_group **sg) +static int +cpu_to_cpu_group(int cpu, const cpumask_t *cpu_map, struct sched_group **sg) { if (sg) *sg = &per_cpu(sched_group_cpus, cpu); @@ -5998,8 +6020,8 @@ static DEFINE_PER_CPU(struct sched_group, sched_group_core); #endif #if defined(CONFIG_SCHED_MC) && defined(CONFIG_SCHED_SMT) -static int cpu_to_core_group(int cpu, const cpumask_t *cpu_map, - struct sched_group **sg) +static int +cpu_to_core_group(int cpu, const cpumask_t *cpu_map, struct sched_group **sg) { int group; cpumask_t mask = per_cpu(cpu_sibling_map, cpu); @@ -6010,8 +6032,8 @@ static int cpu_to_core_group(int cpu, const cpumask_t *cpu_map, return group; } #elif defined(CONFIG_SCHED_MC) -static int cpu_to_core_group(int cpu, const cpumask_t *cpu_map, - struct sched_group **sg) +static int +cpu_to_core_group(int cpu, const cpumask_t *cpu_map, struct sched_group **sg) { if (sg) *sg = &per_cpu(sched_group_core, cpu); @@ -6022,8 +6044,8 @@ static int cpu_to_core_group(int cpu, const cpumask_t *cpu_map, static DEFINE_PER_CPU(struct sched_domain, phys_domains); static DEFINE_PER_CPU(struct sched_group, sched_group_phys); -static int cpu_to_phys_group(int cpu, const cpumask_t *cpu_map, - struct sched_group **sg) +static int +cpu_to_phys_group(int cpu, const cpumask_t *cpu_map, struct sched_group **sg) { int group; #ifdef CONFIG_SCHED_MC @@ -6203,7 +6225,7 @@ static int build_sched_domains(const cpumask_t *cpu_map) * Allocate the per-node list of sched groups */ sched_group_nodes = kcalloc(MAX_NUMNODES, sizeof(struct sched_group *), - GFP_KERNEL); + GFP_KERNEL); if (!sched_group_nodes) { printk(KERN_WARNING "Can not alloc sched group node list\n"); return -ENOMEM; @@ -6450,7 +6472,7 @@ static int ndoms_cur; /* number of sched domains in 'doms_cur' */ static cpumask_t fallback_doms; /* - * Set up scheduler domains and groups. Callers must hold the hotplug lock. + * Set up scheduler domains and groups. Callers must hold the hotplug lock. * For now this just excludes isolated cpus, but could be used to * exclude other special cases in the future. */ @@ -6492,19 +6514,19 @@ static void detach_destroy_domains(const cpumask_t *cpu_map) /* * Partition sched domains as specified by the 'ndoms_new' - * cpumasks in the array doms_new[] of cpumasks. This compares + * cpumasks in the array doms_new[] of cpumasks. This compares * doms_new[] to the current sched domain partitioning, doms_cur[]. * It destroys each deleted domain and builds each new domain. * * 'doms_new' is an array of cpumask_t's of length 'ndoms_new'. - * The masks don't intersect (don't overlap.) We should setup one - * sched domain for each mask. CPUs not in any of the cpumasks will - * not be load balanced. If the same cpumask appears both in the + * The masks don't intersect (don't overlap.) We should setup one + * sched domain for each mask. CPUs not in any of the cpumasks will + * not be load balanced. If the same cpumask appears both in the * current 'doms_cur' domains and in the new 'doms_new', we can leave * it as it is. * - * The passed in 'doms_new' should be kmalloc'd. This routine takes - * ownership of it and will kfree it when done with it. If the caller + * The passed in 'doms_new' should be kmalloc'd. This routine takes + * ownership of it and will kfree it when done with it. If the caller * failed the kmalloc call, then it can pass in doms_new == NULL, * and partition_sched_domains() will fallback to the single partition * 'fallback_doms'. @@ -6634,7 +6656,7 @@ int sched_create_sysfs_power_savings_entries(struct sysdev_class *cls) #endif /* - * Force a reinitialization of the sched domains hierarchy. The domains + * Force a reinitialization of the sched domains hierarchy. The domains * and groups cannot be updated in place without racing with the balancing * code, so we temporarily attach all running cpus to the NULL domain * which will prevent rebalancing while the sched domains are recalculated. @@ -6688,18 +6710,17 @@ void __init sched_init_smp(void) /* Move init over to a non-isolated CPU */ if (set_cpus_allowed(current, non_isolated_cpus) < 0) BUG(); + sched_init_granularity(); } #else void __init sched_init_smp(void) { + sched_init_granularity(); } #endif /* CONFIG_SMP */ int in_sched_functions(unsigned long addr) { - /* Linker adds these: start and end of __sched functions */ - extern char __sched_text_start[], __sched_text_end[]; - return in_lock_functions(addr) || (addr >= (unsigned long)__sched_text_start && addr < (unsigned long)__sched_text_end); @@ -6925,8 +6946,8 @@ struct task_struct *curr_task(int cpu) * @p: the task pointer to set. * * Description: This function must only be used when non-maskable interrupts - * are serviced on a separate stack. It allows the architecture to switch the - * notion of the current task on a cpu in a non-blocking manner. This function + * are serviced on a separate stack. It allows the architecture to switch the + * notion of the current task on a cpu in a non-blocking manner. This function * must be called with all CPU's synchronized, and interrupts disabled, the * and caller must save the original value of the current task (see * curr_task() above) and restore that value before reenabling interrupts and @@ -7068,8 +7089,10 @@ void sched_move_task(struct task_struct *tsk) rq = task_rq_lock(tsk, &flags); - if (tsk->sched_class != &fair_sched_class) + if (tsk->sched_class != &fair_sched_class) { + set_task_cfs_rq(tsk, task_cpu(tsk)); goto done; + } update_rq_clock(rq); @@ -7082,7 +7105,7 @@ void sched_move_task(struct task_struct *tsk) tsk->sched_class->put_prev_task(rq, tsk); } - set_task_cfs_rq(tsk); + set_task_cfs_rq(tsk, task_cpu(tsk)); if (on_rq) { if (unlikely(running)) @@ -7173,16 +7196,17 @@ cpu_cgroup_create(struct cgroup_subsys *ss, struct cgroup *cgrp) return &tg->css; } -static void cpu_cgroup_destroy(struct cgroup_subsys *ss, - struct cgroup *cgrp) +static void +cpu_cgroup_destroy(struct cgroup_subsys *ss, struct cgroup *cgrp) { struct task_group *tg = cgroup_tg(cgrp); sched_destroy_group(tg); } -static int cpu_cgroup_can_attach(struct cgroup_subsys *ss, - struct cgroup *cgrp, struct task_struct *tsk) +static int +cpu_cgroup_can_attach(struct cgroup_subsys *ss, struct cgroup *cgrp, + struct task_struct *tsk) { /* We don't support RT-tasks being in separate groups */ if (tsk->sched_class != &fair_sched_class) @@ -7211,38 +7235,12 @@ static u64 cpu_shares_read_uint(struct cgroup *cgrp, struct cftype *cft) return (u64) tg->shares; } -static u64 cpu_usage_read(struct cgroup *cgrp, struct cftype *cft) -{ - struct task_group *tg = cgroup_tg(cgrp); - unsigned long flags; - u64 res = 0; - int i; - - for_each_possible_cpu(i) { - /* - * Lock to prevent races with updating 64-bit counters - * on 32-bit arches. - */ - spin_lock_irqsave(&cpu_rq(i)->lock, flags); - res += tg->se[i]->sum_exec_runtime; - spin_unlock_irqrestore(&cpu_rq(i)->lock, flags); - } - /* Convert from ns to ms */ - do_div(res, 1000000); - - return res; -} - static struct cftype cpu_files[] = { { .name = "shares", .read_uint = cpu_shares_read_uint, .write_uint = cpu_shares_write_uint, }, - { - .name = "usage", - .read_uint = cpu_usage_read, - }, }; static int cpu_cgroup_populate(struct cgroup_subsys *ss, struct cgroup *cont) @@ -7262,3 +7260,126 @@ struct cgroup_subsys cpu_cgroup_subsys = { }; #endif /* CONFIG_FAIR_CGROUP_SCHED */ + +#ifdef CONFIG_CGROUP_CPUACCT + +/* + * CPU accounting code for task groups. + * + * Based on the work by Paul Menage (menage@google.com) and Balbir Singh + * (balbir@in.ibm.com). + */ + +/* track cpu usage of a group of tasks */ +struct cpuacct { + struct cgroup_subsys_state css; + /* cpuusage holds pointer to a u64-type object on every cpu */ + u64 *cpuusage; +}; + +struct cgroup_subsys cpuacct_subsys; + +/* return cpu accounting group corresponding to this container */ +static inline struct cpuacct *cgroup_ca(struct cgroup *cont) +{ + return container_of(cgroup_subsys_state(cont, cpuacct_subsys_id), + struct cpuacct, css); +} + +/* return cpu accounting group to which this task belongs */ +static inline struct cpuacct *task_ca(struct task_struct *tsk) +{ + return container_of(task_subsys_state(tsk, cpuacct_subsys_id), + struct cpuacct, css); +} + +/* create a new cpu accounting group */ +static struct cgroup_subsys_state *cpuacct_create( + struct cgroup_subsys *ss, struct cgroup *cont) +{ + struct cpuacct *ca = kzalloc(sizeof(*ca), GFP_KERNEL); + + if (!ca) + return ERR_PTR(-ENOMEM); + + ca->cpuusage = alloc_percpu(u64); + if (!ca->cpuusage) { + kfree(ca); + return ERR_PTR(-ENOMEM); + } + + return &ca->css; +} + +/* destroy an existing cpu accounting group */ +static void +cpuacct_destroy(struct cgroup_subsys *ss, struct cgroup *cont) +{ + struct cpuacct *ca = cgroup_ca(cont); + + free_percpu(ca->cpuusage); + kfree(ca); +} + +/* return total cpu usage (in nanoseconds) of a group */ +static u64 cpuusage_read(struct cgroup *cont, struct cftype *cft) +{ + struct cpuacct *ca = cgroup_ca(cont); + u64 totalcpuusage = 0; + int i; + + for_each_possible_cpu(i) { + u64 *cpuusage = percpu_ptr(ca->cpuusage, i); + + /* + * Take rq->lock to make 64-bit addition safe on 32-bit + * platforms. + */ + spin_lock_irq(&cpu_rq(i)->lock); + totalcpuusage += *cpuusage; + spin_unlock_irq(&cpu_rq(i)->lock); + } + + return totalcpuusage; +} + +static struct cftype files[] = { + { + .name = "usage", + .read_uint = cpuusage_read, + }, +}; + +static int cpuacct_populate(struct cgroup_subsys *ss, struct cgroup *cont) +{ + return cgroup_add_files(cont, ss, files, ARRAY_SIZE(files)); +} + +/* + * charge this task's execution time to its accounting group. + * + * called with rq->lock held. + */ +static void cpuacct_charge(struct task_struct *tsk, u64 cputime) +{ + struct cpuacct *ca; + + if (!cpuacct_subsys.active) + return; + + ca = task_ca(tsk); + if (ca) { + u64 *cpuusage = percpu_ptr(ca->cpuusage, task_cpu(tsk)); + + *cpuusage += cputime; + } +} + +struct cgroup_subsys cpuacct_subsys = { + .name = "cpuacct", + .create = cpuacct_create, + .destroy = cpuacct_destroy, + .populate = cpuacct_populate, + .subsys_id = cpuacct_subsys_id, +}; +#endif /* CONFIG_CGROUP_CPUACCT */