diff options
-rw-r--r-- | include/linux/cgroup-defs.h | 16 | ||||
-rw-r--r-- | kernel/cgroup/cgroup-internal.h | 10 | ||||
-rw-r--r-- | kernel/cgroup/cgroup.c | 14 | ||||
-rw-r--r-- | kernel/cgroup/rstat.c | 180 |
4 files changed, 112 insertions, 108 deletions
diff --git a/include/linux/cgroup-defs.h b/include/linux/cgroup-defs.h index 133531fcfb33..04cb42419310 100644 --- a/include/linux/cgroup-defs.h +++ b/include/linux/cgroup-defs.h @@ -259,11 +259,11 @@ struct css_set { }; /* - * cgroup basic resource usage statistics. Accounting is done per-cpu in - * cgroup_cpu_stat which is then lazily propagated up the hierarchy on - * reads. + * rstat - cgroup scalable recursive statistics. Accounting is done + * per-cpu in cgroup_rstat_cpu which is then lazily propagated up the + * hierarchy on reads. * - * When a stat gets updated, the cgroup_cpu_stat and its ancestors are + * When a stat gets updated, the cgroup_rstat_cpu and its ancestors are * linked into the updated tree. On the following read, propagation only * considers and consumes the updated tree. This makes reading O(the * number of descendants which have been active since last read) instead of @@ -274,7 +274,7 @@ struct css_set { * become very expensive. By propagating selectively, increasing reading * frequency decreases the cost of each read. */ -struct cgroup_cpu_stat { +struct cgroup_rstat_cpu { /* * ->sync protects all the current counters. These are the only * fields which get updated in the hot path. @@ -297,7 +297,7 @@ struct cgroup_cpu_stat { * to the cgroup makes it unnecessary for each per-cpu struct to * point back to the associated cgroup. * - * Protected by per-cpu cgroup_cpu_stat_lock. + * Protected by per-cpu cgroup_rstat_cpu_lock. */ struct cgroup *updated_children; /* terminated by self cgroup */ struct cgroup *updated_next; /* NULL iff not on the list */ @@ -408,8 +408,10 @@ struct cgroup { */ struct cgroup *dom_cgrp; + /* per-cpu recursive resource statistics */ + struct cgroup_rstat_cpu __percpu *rstat_cpu; + /* cgroup basic resource statistics */ - struct cgroup_cpu_stat __percpu *cpu_stat; struct cgroup_stat pending_stat; /* pending from children */ struct cgroup_stat stat; diff --git a/kernel/cgroup/cgroup-internal.h b/kernel/cgroup/cgroup-internal.h index b928b27050c6..092711114a1f 100644 --- a/kernel/cgroup/cgroup-internal.h +++ b/kernel/cgroup/cgroup-internal.h @@ -201,13 +201,13 @@ int cgroup_show_path(struct seq_file *sf, struct kernfs_node *kf_node, int cgroup_task_count(const struct cgroup *cgrp); /* - * stat.c + * rstat.c */ -void cgroup_stat_flush(struct cgroup *cgrp); -int cgroup_stat_init(struct cgroup *cgrp); -void cgroup_stat_exit(struct cgroup *cgrp); +void cgroup_rstat_flush(struct cgroup *cgrp); +int cgroup_rstat_init(struct cgroup *cgrp); +void cgroup_rstat_exit(struct cgroup *cgrp); void cgroup_stat_show_cputime(struct seq_file *seq); -void cgroup_stat_boot(void); +void cgroup_rstat_boot(void); /* * namespace.c diff --git a/kernel/cgroup/cgroup.c b/kernel/cgroup/cgroup.c index fdb7a582f8fc..32eb7ce0ad71 100644 --- a/kernel/cgroup/cgroup.c +++ b/kernel/cgroup/cgroup.c @@ -144,14 +144,14 @@ static struct static_key_true *cgroup_subsys_on_dfl_key[] = { }; #undef SUBSYS -static DEFINE_PER_CPU(struct cgroup_cpu_stat, cgrp_dfl_root_cpu_stat); +static DEFINE_PER_CPU(struct cgroup_rstat_cpu, cgrp_dfl_root_rstat_cpu); /* * The default hierarchy, reserved for the subsystems that are otherwise * unattached - it never has more than a single cgroup, and all tasks are * part of that cgroup. */ -struct cgroup_root cgrp_dfl_root = { .cgrp.cpu_stat = &cgrp_dfl_root_cpu_stat }; +struct cgroup_root cgrp_dfl_root = { .cgrp.rstat_cpu = &cgrp_dfl_root_rstat_cpu }; EXPORT_SYMBOL_GPL(cgrp_dfl_root); /* @@ -4592,7 +4592,7 @@ static void css_free_rwork_fn(struct work_struct *work) cgroup_put(cgroup_parent(cgrp)); kernfs_put(cgrp->kn); if (cgroup_on_dfl(cgrp)) - cgroup_stat_exit(cgrp); + cgroup_rstat_exit(cgrp); kfree(cgrp); } else { /* @@ -4629,7 +4629,7 @@ static void css_release_work_fn(struct work_struct *work) trace_cgroup_release(cgrp); if (cgroup_on_dfl(cgrp)) - cgroup_stat_flush(cgrp); + cgroup_rstat_flush(cgrp); for (tcgrp = cgroup_parent(cgrp); tcgrp; tcgrp = cgroup_parent(tcgrp)) @@ -4817,7 +4817,7 @@ static struct cgroup *cgroup_create(struct cgroup *parent) goto out_free_cgrp; if (cgroup_on_dfl(parent)) { - ret = cgroup_stat_init(cgrp); + ret = cgroup_rstat_init(cgrp); if (ret) goto out_cancel_ref; } @@ -4882,7 +4882,7 @@ out_idr_free: cgroup_idr_remove(&root->cgroup_idr, cgrp->id); out_stat_exit: if (cgroup_on_dfl(parent)) - cgroup_stat_exit(cgrp); + cgroup_rstat_exit(cgrp); out_cancel_ref: percpu_ref_exit(&cgrp->self.refcnt); out_free_cgrp: @@ -5275,7 +5275,7 @@ int __init cgroup_init(void) BUG_ON(cgroup_init_cftypes(NULL, cgroup_base_files)); BUG_ON(cgroup_init_cftypes(NULL, cgroup1_base_files)); - cgroup_stat_boot(); + cgroup_rstat_boot(); /* * The latency of the synchronize_sched() is too high for cgroups, diff --git a/kernel/cgroup/rstat.c b/kernel/cgroup/rstat.c index 1e111dd455c4..6824047b57a9 100644 --- a/kernel/cgroup/rstat.c +++ b/kernel/cgroup/rstat.c @@ -2,26 +2,26 @@ #include <linux/sched/cputime.h> -static DEFINE_MUTEX(cgroup_stat_mutex); -static DEFINE_PER_CPU(raw_spinlock_t, cgroup_cpu_stat_lock); +static DEFINE_MUTEX(cgroup_rstat_mutex); +static DEFINE_PER_CPU(raw_spinlock_t, cgroup_rstat_cpu_lock); -static struct cgroup_cpu_stat *cgroup_cpu_stat(struct cgroup *cgrp, int cpu) +static struct cgroup_rstat_cpu *cgroup_rstat_cpu(struct cgroup *cgrp, int cpu) { - return per_cpu_ptr(cgrp->cpu_stat, cpu); + return per_cpu_ptr(cgrp->rstat_cpu, cpu); } /** - * cgroup_cpu_stat_updated - keep track of updated cpu_stat + * cgroup_rstat_cpu_updated - keep track of updated rstat_cpu * @cgrp: target cgroup - * @cpu: cpu on which cpu_stat was updated + * @cpu: cpu on which rstat_cpu was updated * - * @cgrp's cpu_stat on @cpu was updated. Put it on the parent's matching - * cpu_stat->updated_children list. See the comment on top of - * cgroup_cpu_stat definition for details. + * @cgrp's rstat_cpu on @cpu was updated. Put it on the parent's matching + * rstat_cpu->updated_children list. See the comment on top of + * cgroup_rstat_cpu definition for details. */ -static void cgroup_cpu_stat_updated(struct cgroup *cgrp, int cpu) +static void cgroup_rstat_cpu_updated(struct cgroup *cgrp, int cpu) { - raw_spinlock_t *cpu_lock = per_cpu_ptr(&cgroup_cpu_stat_lock, cpu); + raw_spinlock_t *cpu_lock = per_cpu_ptr(&cgroup_rstat_cpu_lock, cpu); struct cgroup *parent; unsigned long flags; @@ -33,7 +33,7 @@ static void cgroup_cpu_stat_updated(struct cgroup *cgrp, int cpu) * instead of NULL, we can tell whether @cgrp is on the list by * testing the next pointer for NULL. */ - if (cgroup_cpu_stat(cgrp, cpu)->updated_next) + if (cgroup_rstat_cpu(cgrp, cpu)->updated_next) return; raw_spin_lock_irqsave(cpu_lock, flags); @@ -41,42 +41,42 @@ static void cgroup_cpu_stat_updated(struct cgroup *cgrp, int cpu) /* put @cgrp and all ancestors on the corresponding updated lists */ for (parent = cgroup_parent(cgrp); parent; cgrp = parent, parent = cgroup_parent(cgrp)) { - struct cgroup_cpu_stat *cstat = cgroup_cpu_stat(cgrp, cpu); - struct cgroup_cpu_stat *pcstat = cgroup_cpu_stat(parent, cpu); + struct cgroup_rstat_cpu *rstatc = cgroup_rstat_cpu(cgrp, cpu); + struct cgroup_rstat_cpu *prstatc = cgroup_rstat_cpu(parent, cpu); /* * Both additions and removals are bottom-up. If a cgroup * is already in the tree, all ancestors are. */ - if (cstat->updated_next) + if (rstatc->updated_next) break; - cstat->updated_next = pcstat->updated_children; - pcstat->updated_children = cgrp; + rstatc->updated_next = prstatc->updated_children; + prstatc->updated_children = cgrp; } raw_spin_unlock_irqrestore(cpu_lock, flags); } /** - * cgroup_cpu_stat_pop_updated - iterate and dismantle cpu_stat updated tree + * cgroup_rstat_cpu_pop_updated - iterate and dismantle rstat_cpu updated tree * @pos: current position * @root: root of the tree to traversal * @cpu: target cpu * - * Walks the udpated cpu_stat tree on @cpu from @root. %NULL @pos starts + * Walks the udpated rstat_cpu tree on @cpu from @root. %NULL @pos starts * the traversal and %NULL return indicates the end. During traversal, * each returned cgroup is unlinked from the tree. Must be called with the - * matching cgroup_cpu_stat_lock held. + * matching cgroup_rstat_cpu_lock held. * * The only ordering guarantee is that, for a parent and a child pair * covered by a given traversal, if a child is visited, its parent is * guaranteed to be visited afterwards. */ -static struct cgroup *cgroup_cpu_stat_pop_updated(struct cgroup *pos, - struct cgroup *root, int cpu) +static struct cgroup *cgroup_rstat_cpu_pop_updated(struct cgroup *pos, + struct cgroup *root, int cpu) { - struct cgroup_cpu_stat *cstat; + struct cgroup_rstat_cpu *rstatc; struct cgroup *parent; if (pos == root) @@ -93,10 +93,10 @@ static struct cgroup *cgroup_cpu_stat_pop_updated(struct cgroup *pos, /* walk down to the first leaf */ while (true) { - cstat = cgroup_cpu_stat(pos, cpu); - if (cstat->updated_children == pos) + rstatc = cgroup_rstat_cpu(pos, cpu); + if (rstatc->updated_children == pos) break; - pos = cstat->updated_children; + pos = rstatc->updated_children; } /* @@ -106,23 +106,23 @@ static struct cgroup *cgroup_cpu_stat_pop_updated(struct cgroup *pos, * child in most cases. The only exception is @root. */ parent = cgroup_parent(pos); - if (parent && cstat->updated_next) { - struct cgroup_cpu_stat *pcstat = cgroup_cpu_stat(parent, cpu); - struct cgroup_cpu_stat *ncstat; + if (parent && rstatc->updated_next) { + struct cgroup_rstat_cpu *prstatc = cgroup_rstat_cpu(parent, cpu); + struct cgroup_rstat_cpu *nrstatc; struct cgroup **nextp; - nextp = &pcstat->updated_children; + nextp = &prstatc->updated_children; while (true) { - ncstat = cgroup_cpu_stat(*nextp, cpu); + nrstatc = cgroup_rstat_cpu(*nextp, cpu); if (*nextp == pos) break; WARN_ON_ONCE(*nextp == parent); - nextp = &ncstat->updated_next; + nextp = &nrstatc->updated_next; } - *nextp = cstat->updated_next; - cstat->updated_next = NULL; + *nextp = rstatc->updated_next; + rstatc->updated_next = NULL; } return pos; @@ -139,19 +139,19 @@ static void cgroup_stat_accumulate(struct cgroup_stat *dst_stat, static void cgroup_cpu_stat_flush_one(struct cgroup *cgrp, int cpu) { struct cgroup *parent = cgroup_parent(cgrp); - struct cgroup_cpu_stat *cstat = cgroup_cpu_stat(cgrp, cpu); - struct task_cputime *last_cputime = &cstat->last_cputime; + struct cgroup_rstat_cpu *rstatc = cgroup_rstat_cpu(cgrp, cpu); + struct task_cputime *last_cputime = &rstatc->last_cputime; struct task_cputime cputime; struct cgroup_stat delta; unsigned seq; - lockdep_assert_held(&cgroup_stat_mutex); + lockdep_assert_held(&cgroup_rstat_mutex); /* fetch the current per-cpu values */ do { - seq = __u64_stats_fetch_begin(&cstat->sync); - cputime = cstat->cputime; - } while (__u64_stats_fetch_retry(&cstat->sync, seq)); + seq = __u64_stats_fetch_begin(&rstatc->sync); + cputime = rstatc->cputime; + } while (__u64_stats_fetch_retry(&rstatc->sync, seq)); /* accumulate the deltas to propgate */ delta.cputime.utime = cputime.utime - last_cputime->utime; @@ -170,26 +170,27 @@ static void cgroup_cpu_stat_flush_one(struct cgroup *cgrp, int cpu) cgroup_stat_accumulate(&parent->pending_stat, &delta); } -/* see cgroup_stat_flush() */ -static void cgroup_stat_flush_locked(struct cgroup *cgrp) +/* see cgroup_rstat_flush() */ +static void cgroup_rstat_flush_locked(struct cgroup *cgrp) { int cpu; - lockdep_assert_held(&cgroup_stat_mutex); + lockdep_assert_held(&cgroup_rstat_mutex); for_each_possible_cpu(cpu) { - raw_spinlock_t *cpu_lock = per_cpu_ptr(&cgroup_cpu_stat_lock, cpu); + raw_spinlock_t *cpu_lock = per_cpu_ptr(&cgroup_rstat_cpu_lock, + cpu); struct cgroup *pos = NULL; raw_spin_lock_irq(cpu_lock); - while ((pos = cgroup_cpu_stat_pop_updated(pos, cgrp, cpu))) + while ((pos = cgroup_rstat_cpu_pop_updated(pos, cgrp, cpu))) cgroup_cpu_stat_flush_one(pos, cpu); raw_spin_unlock_irq(cpu_lock); } } /** - * cgroup_stat_flush - flush stats in @cgrp's subtree + * cgroup_rstat_flush - flush stats in @cgrp's subtree * @cgrp: target cgroup * * Collect all per-cpu stats in @cgrp's subtree into the global counters @@ -199,61 +200,62 @@ static void cgroup_stat_flush_locked(struct cgroup *cgrp) * This also gets all cgroups in the subtree including @cgrp off the * ->updated_children lists. */ -void cgroup_stat_flush(struct cgroup *cgrp) +void cgroup_rstat_flush(struct cgroup *cgrp) { - mutex_lock(&cgroup_stat_mutex); - cgroup_stat_flush_locked(cgrp); - mutex_unlock(&cgroup_stat_mutex); + mutex_lock(&cgroup_rstat_mutex); + cgroup_rstat_flush_locked(cgrp); + mutex_unlock(&cgroup_rstat_mutex); } -static struct cgroup_cpu_stat *cgroup_cpu_stat_account_begin(struct cgroup *cgrp) +static struct cgroup_rstat_cpu * +cgroup_cpu_stat_account_begin(struct cgroup *cgrp) { - struct cgroup_cpu_stat *cstat; + struct cgroup_rstat_cpu *rstatc; - cstat = get_cpu_ptr(cgrp->cpu_stat); - u64_stats_update_begin(&cstat->sync); - return cstat; + rstatc = get_cpu_ptr(cgrp->rstat_cpu); + u64_stats_update_begin(&rstatc->sync); + return rstatc; } static void cgroup_cpu_stat_account_end(struct cgroup *cgrp, - struct cgroup_cpu_stat *cstat) + struct cgroup_rstat_cpu *rstatc) { - u64_stats_update_end(&cstat->sync); - cgroup_cpu_stat_updated(cgrp, smp_processor_id()); - put_cpu_ptr(cstat); + u64_stats_update_end(&rstatc->sync); + cgroup_rstat_cpu_updated(cgrp, smp_processor_id()); + put_cpu_ptr(rstatc); } void __cgroup_account_cputime(struct cgroup *cgrp, u64 delta_exec) { - struct cgroup_cpu_stat *cstat; + struct cgroup_rstat_cpu *rstatc; - cstat = cgroup_cpu_stat_account_begin(cgrp); - cstat->cputime.sum_exec_runtime += delta_exec; - cgroup_cpu_stat_account_end(cgrp, cstat); + rstatc = cgroup_cpu_stat_account_begin(cgrp); + rstatc->cputime.sum_exec_runtime += delta_exec; + cgroup_cpu_stat_account_end(cgrp, rstatc); } void __cgroup_account_cputime_field(struct cgroup *cgrp, enum cpu_usage_stat index, u64 delta_exec) { - struct cgroup_cpu_stat *cstat; + struct cgroup_rstat_cpu *rstatc; - cstat = cgroup_cpu_stat_account_begin(cgrp); + rstatc = cgroup_cpu_stat_account_begin(cgrp); switch (index) { case CPUTIME_USER: case CPUTIME_NICE: - cstat->cputime.utime += delta_exec; + rstatc->cputime.utime += delta_exec; break; case CPUTIME_SYSTEM: case CPUTIME_IRQ: case CPUTIME_SOFTIRQ: - cstat->cputime.stime += delta_exec; + rstatc->cputime.stime += delta_exec; break; default: break; } - cgroup_cpu_stat_account_end(cgrp, cstat); + cgroup_cpu_stat_account_end(cgrp, rstatc); } void cgroup_stat_show_cputime(struct seq_file *seq) @@ -264,15 +266,15 @@ void cgroup_stat_show_cputime(struct seq_file *seq) if (!cgroup_parent(cgrp)) return; - mutex_lock(&cgroup_stat_mutex); + mutex_lock(&cgroup_rstat_mutex); - cgroup_stat_flush_locked(cgrp); + cgroup_rstat_flush_locked(cgrp); usage = cgrp->stat.cputime.sum_exec_runtime; cputime_adjust(&cgrp->stat.cputime, &cgrp->stat.prev_cputime, &utime, &stime); - mutex_unlock(&cgroup_stat_mutex); + mutex_unlock(&cgroup_rstat_mutex); do_div(usage, NSEC_PER_USEC); do_div(utime, NSEC_PER_USEC); @@ -284,23 +286,23 @@ void cgroup_stat_show_cputime(struct seq_file *seq) usage, utime, stime); } -int cgroup_stat_init(struct cgroup *cgrp) +int cgroup_rstat_init(struct cgroup *cgrp) { int cpu; - /* the root cgrp has cpu_stat preallocated */ - if (!cgrp->cpu_stat) { - cgrp->cpu_stat = alloc_percpu(struct cgroup_cpu_stat); - if (!cgrp->cpu_stat) + /* the root cgrp has rstat_cpu preallocated */ + if (!cgrp->rstat_cpu) { + cgrp->rstat_cpu = alloc_percpu(struct cgroup_rstat_cpu); + if (!cgrp->rstat_cpu) return -ENOMEM; } /* ->updated_children list is self terminated */ for_each_possible_cpu(cpu) { - struct cgroup_cpu_stat *cstat = cgroup_cpu_stat(cgrp, cpu); + struct cgroup_rstat_cpu *rstatc = cgroup_rstat_cpu(cgrp, cpu); - cstat->updated_children = cgrp; - u64_stats_init(&cstat->sync); + rstatc->updated_children = cgrp; + u64_stats_init(&rstatc->sync); } prev_cputime_init(&cgrp->stat.prev_cputime); @@ -308,31 +310,31 @@ int cgroup_stat_init(struct cgroup *cgrp) return 0; } -void cgroup_stat_exit(struct cgroup *cgrp) +void cgroup_rstat_exit(struct cgroup *cgrp) { int cpu; - cgroup_stat_flush(cgrp); + cgroup_rstat_flush(cgrp); /* sanity check */ for_each_possible_cpu(cpu) { - struct cgroup_cpu_stat *cstat = cgroup_cpu_stat(cgrp, cpu); + struct cgroup_rstat_cpu *rstatc = cgroup_rstat_cpu(cgrp, cpu); - if (WARN_ON_ONCE(cstat->updated_children != cgrp) || - WARN_ON_ONCE(cstat->updated_next)) + if (WARN_ON_ONCE(rstatc->updated_children != cgrp) || + WARN_ON_ONCE(rstatc->updated_next)) return; } - free_percpu(cgrp->cpu_stat); - cgrp->cpu_stat = NULL; + free_percpu(cgrp->rstat_cpu); + cgrp->rstat_cpu = NULL; } -void __init cgroup_stat_boot(void) +void __init cgroup_rstat_boot(void) { int cpu; for_each_possible_cpu(cpu) - raw_spin_lock_init(per_cpu_ptr(&cgroup_cpu_stat_lock, cpu)); + raw_spin_lock_init(per_cpu_ptr(&cgroup_rstat_cpu_lock, cpu)); - BUG_ON(cgroup_stat_init(&cgrp_dfl_root.cgrp)); + BUG_ON(cgroup_rstat_init(&cgrp_dfl_root.cgrp)); } |