diff options
| -rw-r--r-- | Documentation/cgroup-v2.txt | 42 | ||||
| -rw-r--r-- | MAINTAINERS | 2 | ||||
| -rw-r--r-- | include/linux/cgroup-defs.h | 59 | ||||
| -rw-r--r-- | include/linux/cgroup.h | 58 | ||||
| -rw-r--r-- | include/linux/sched/cputime.h | 3 | ||||
| -rw-r--r-- | kernel/cgroup/Makefile | 2 | ||||
| -rw-r--r-- | kernel/cgroup/cgroup-internal.h | 9 | ||||
| -rw-r--r-- | kernel/cgroup/cgroup.c | 157 | ||||
| -rw-r--r-- | kernel/cgroup/stat.c | 334 | ||||
| -rw-r--r-- | kernel/sched/core.c | 174 | ||||
| -rw-r--r-- | kernel/sched/cpuacct.h | 18 | ||||
| -rw-r--r-- | kernel/sched/cputime.c | 14 | ||||
| -rw-r--r-- | kernel/sched/deadline.c | 2 | ||||
| -rw-r--r-- | kernel/sched/fair.c | 2 | ||||
| -rw-r--r-- | kernel/sched/rt.c | 2 | ||||
| -rw-r--r-- | kernel/sched/sched.h | 2 | ||||
| -rw-r--r-- | kernel/sched/stop_task.c | 2 |
17 files changed, 821 insertions, 61 deletions
diff --git a/Documentation/cgroup-v2.txt b/Documentation/cgroup-v2.txt index dc44785..779211f 100644 --- a/Documentation/cgroup-v2.txt +++ b/Documentation/cgroup-v2.txt @@ -893,10 +893,6 @@ Controllers CPU --- -.. note:: - - The interface for the cpu controller hasn't been merged yet - The "cpu" controllers regulates distribution of CPU cycles. This controller implements weight and absolute bandwidth limit models for normal scheduling policy and absolute bandwidth allocation model for @@ -910,12 +906,16 @@ All time durations are in microseconds. cpu.stat A read-only flat-keyed file which exists on non-root cgroups. + This file exists whether the controller is enabled or not. - It reports the following six stats: + It always reports the following three stats: - usage_usec - user_usec - system_usec + + and the following three when the controller is enabled: + - nr_periods - nr_throttled - throttled_usec @@ -926,6 +926,18 @@ All time durations are in microseconds. The weight in the range [1, 10000]. + cpu.weight.nice + A read-write single value file which exists on non-root + cgroups. The default is "0". + + The nice value is in the range [-20, 19]. + + This interface file is an alternative interface for + "cpu.weight" and allows reading and setting weight using the + same values used by nice(2). Because the range is smaller and + granularity is coarser for the nice values, the read value is + the closest approximation of the current weight. + cpu.max A read-write two value file which exists on non-root cgroups. The default is "max 100000". @@ -938,26 +950,6 @@ All time durations are in microseconds. $PERIOD duration. "max" for $MAX indicates no limit. If only one number is written, $MAX is updated. - cpu.rt.max - .. note:: - - The semantics of this file is still under discussion and the - interface hasn't been merged yet - - A read-write two value file which exists on all cgroups. - The default is "0 100000". - - The maximum realtime runtime allocation. Over-committing - configurations are disallowed and process migrations are - rejected if not enough bandwidth is available. It's in the - following format:: - - $MAX $PERIOD - - which indicates that the group may consume upto $MAX in each - $PERIOD duration. If only one number is written, $MAX is - updated. - Memory ------ diff --git a/MAINTAINERS b/MAINTAINERS index 16e1e6d..a74d6a7 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -3592,7 +3592,7 @@ T: git git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup.git S: Maintained F: Documentation/cgroup-v1/cpusets.txt F: include/linux/cpuset.h -F: kernel/cpuset.c +F: kernel/cgroup/cpuset.c CONTROL GROUP - MEMORY RESOURCE CONTROLLER (MEMCG) M: Johannes Weiner <hannes@cmpxchg.org> diff --git a/include/linux/cgroup-defs.h b/include/linux/cgroup-defs.h index 1dff0a4..8b7fd8e 100644 --- a/include/linux/cgroup-defs.h +++ b/include/linux/cgroup-defs.h @@ -17,6 +17,7 @@ #include <linux/refcount.h> #include <linux/percpu-refcount.h> #include <linux/percpu-rwsem.h> +#include <linux/u64_stats_sync.h> #include <linux/workqueue.h> #include <linux/bpf-cgroup.h> @@ -255,6 +256,57 @@ struct css_set { struct rcu_head rcu_head; }; +/* + * cgroup basic resource usage statistics. Accounting is done per-cpu in + * cgroup_cpu_stat which is then lazily propagated up the hierarchy on + * reads. + * + * When a stat gets updated, the cgroup_cpu_stat 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 + * O(the total number of descendants). + * + * This is important because there can be a lot of (draining) cgroups which + * aren't active and stat may be read frequently. The combination can + * become very expensive. By propagating selectively, increasing reading + * frequency decreases the cost of each read. + */ +struct cgroup_cpu_stat { + /* + * ->sync protects all the current counters. These are the only + * fields which get updated in the hot path. + */ + struct u64_stats_sync sync; + struct task_cputime cputime; + + /* + * Snapshots at the last reading. These are used to calculate the + * deltas to propagate to the global counters. + */ + struct task_cputime last_cputime; + + /* + * Child cgroups with stat updates on this cpu since the last read + * are linked on the parent's ->updated_children through + * ->updated_next. + * + * In addition to being more compact, singly-linked list pointing + * 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. + */ + struct cgroup *updated_children; /* terminated by self cgroup */ + struct cgroup *updated_next; /* NULL iff not on the list */ +}; + +struct cgroup_stat { + /* per-cpu statistics are collected into the folowing global counters */ + struct task_cputime cputime; + struct prev_cputime prev_cputime; +}; + struct cgroup { /* self css with NULL ->ss, points back to this cgroup */ struct cgroup_subsys_state self; @@ -354,6 +406,11 @@ struct cgroup { */ struct cgroup *dom_cgrp; + /* cgroup basic resource statistics */ + struct cgroup_cpu_stat __percpu *cpu_stat; + struct cgroup_stat pending_stat; /* pending from children */ + struct cgroup_stat stat; + /* * list of pidlists, up to two for each namespace (one for procs, one * for tasks); created on demand. @@ -513,6 +570,8 @@ struct cgroup_subsys { void (*css_released)(struct cgroup_subsys_state *css); void (*css_free)(struct cgroup_subsys_state *css); void (*css_reset)(struct cgroup_subsys_state *css); + int (*css_extra_stat_show)(struct seq_file *seq, + struct cgroup_subsys_state *css); int (*can_attach)(struct cgroup_taskset *tset); void (*cancel_attach)(struct cgroup_taskset *tset); diff --git a/include/linux/cgroup.h b/include/linux/cgroup.h index dddbc29..473e0c0 100644 --- a/include/linux/cgroup.h +++ b/include/linux/cgroup.h @@ -23,6 +23,7 @@ #include <linux/nsproxy.h> #include <linux/user_namespace.h> #include <linux/refcount.h> +#include <linux/kernel_stat.h> #include <linux/cgroup-defs.h> @@ -690,6 +691,63 @@ static inline void cgroup_path_from_kernfs_id(const union kernfs_node_id *id, #endif /* !CONFIG_CGROUPS */ /* + * Basic resource stats. + */ +#ifdef CONFIG_CGROUPS + +#ifdef CONFIG_CGROUP_CPUACCT +void cpuacct_charge(struct task_struct *tsk, u64 cputime); +void cpuacct_account_field(struct task_struct *tsk, int index, u64 val); +#else +static inline void cpuacct_charge(struct task_struct *tsk, u64 cputime) {} +static inline void cpuacct_account_field(struct task_struct *tsk, int index, + u64 val) {} +#endif + +void __cgroup_account_cputime(struct cgroup *cgrp, u64 delta_exec); +void __cgroup_account_cputime_field(struct cgroup *cgrp, + enum cpu_usage_stat index, u64 delta_exec); + +static inline void cgroup_account_cputime(struct task_struct *task, + u64 delta_exec) +{ + struct cgroup *cgrp; + + cpuacct_charge(task, delta_exec); + + rcu_read_lock(); + cgrp = task_dfl_cgroup(task); + if (cgroup_parent(cgrp)) + __cgroup_account_cputime(cgrp, delta_exec); + rcu_read_unlock(); +} + +static inline void cgroup_account_cputime_field(struct task_struct *task, + enum cpu_usage_stat index, + u64 delta_exec) +{ + struct cgroup *cgrp; + + cpuacct_account_field(task, index, delta_exec); + + rcu_read_lock(); + cgrp = task_dfl_cgroup(task); + if (cgroup_parent(cgrp)) + __cgroup_account_cputime_field(cgrp, index, delta_exec); + rcu_read_unlock(); +} + +#else /* CONFIG_CGROUPS */ + +static inline void cgroup_account_cputime(struct task_struct *task, + u64 delta_exec) {} +static inline void cgroup_account_cputime_field(struct task_struct *task, + enum cpu_usage_stat index, + u64 delta_exec) {} + +#endif /* CONFIG_CGROUPS */ + +/* * sock->sk_cgrp_data handling. For more info, see sock_cgroup_data * definition in cgroup-defs.h. */ diff --git a/include/linux/sched/cputime.h b/include/linux/sched/cputime.h index d0677f6..53f883f 100644 --- a/include/linux/sched/cputime.h +++ b/include/linux/sched/cputime.h @@ -54,7 +54,8 @@ static inline void task_cputime_scaled(struct task_struct *t, extern void task_cputime_adjusted(struct task_struct *p, u64 *ut, u64 *st); extern void thread_group_cputime_adjusted(struct task_struct *p, u64 *ut, u64 *st); - +extern void cputime_adjust(struct task_cputime *curr, struct prev_cputime *prev, + u64 *ut, u64 *st); /* * Thread group CPU time accounting. diff --git a/kernel/cgroup/Makefile b/kernel/cgroup/Makefile index ae448f7..2be89a00 100644 --- a/kernel/cgroup/Makefile +++ b/kernel/cgroup/Makefile @@ -1,5 +1,5 @@ # SPDX-License-Identifier: GPL-2.0 -obj-y := cgroup.o namespace.o cgroup-v1.o +obj-y := cgroup.o stat.o namespace.o cgroup-v1.o obj-$(CONFIG_CGROUP_FREEZER) += freezer.o obj-$(CONFIG_CGROUP_PIDS) += pids.o diff --git a/kernel/cgroup/cgroup-internal.h b/kernel/cgroup/cgroup-internal.h index bf54ade..b928b27 100644 --- a/kernel/cgroup/cgroup-internal.h +++ b/kernel/cgroup/cgroup-internal.h @@ -201,6 +201,15 @@ int cgroup_show_path(struct seq_file *sf, struct kernfs_node *kf_node, int cgroup_task_count(const struct cgroup *cgrp); /* + * stat.c + */ +void cgroup_stat_flush(struct cgroup *cgrp); +int cgroup_stat_init(struct cgroup *cgrp); +void cgroup_stat_exit(struct cgroup *cgrp); +void cgroup_stat_show_cputime(struct seq_file *seq); +void cgroup_stat_boot(void); + +/* * namespace.c */ extern const struct proc_ns_operations cgroupns_operations; diff --git a/kernel/cgroup/cgroup.c b/kernel/cgroup/cgroup.c index 00f5b35..0b1ffe1 100644 --- a/kernel/cgroup/cgroup.c +++ b/kernel/cgroup/cgroup.c @@ -142,12 +142,14 @@ 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); + /* * 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; +struct cgroup_root cgrp_dfl_root = { .cgrp.cpu_stat = &cgrp_dfl_root_cpu_stat }; EXPORT_SYMBOL_GPL(cgrp_dfl_root); /* @@ -462,6 +464,28 @@ static struct cgroup_subsys_state *cgroup_css(struct cgroup *cgrp, } /** + * cgroup_tryget_css - try to get a cgroup's css for the specified subsystem + * @cgrp: the cgroup of interest + * @ss: the subsystem of interest + * + * Find and get @cgrp's css assocaited with @ss. If the css doesn't exist + * or is offline, %NULL is returned. + */ +static struct cgroup_subsys_state *cgroup_tryget_css(struct cgroup *cgrp, + struct cgroup_subsys *ss) +{ + struct cgroup_subsys_state *css; + + rcu_read_lock(); + css = cgroup_css(cgrp, ss); + if (!css || !css_tryget_online(css)) + css = NULL; + rcu_read_unlock(); + + return css; +} + +/** * cgroup_e_css - obtain a cgroup's effective css for the specified subsystem * @cgrp: the cgroup of interest * @ss: the subsystem of interest (%NULL returns @cgrp->self) @@ -647,6 +671,14 @@ struct css_set init_css_set = { .cgrp_links = LIST_HEAD_INIT(init_css_set.cgrp_links), .mg_preload_node = LIST_HEAD_INIT(init_css_set.mg_preload_node), .mg_node = LIST_HEAD_INIT(init_css_set.mg_node), + + /* + * The following field is re-initialized when this cset gets linked + * in cgroup_init(). However, let's initialize the field + * statically too so that the default cgroup can be accessed safely + * early during boot. + */ + .dfl_cgrp = &cgrp_dfl_root.cgrp, }; static int css_set_count = 1; /* 1 for init_css_set */ @@ -3315,6 +3347,37 @@ static int cgroup_stat_show(struct seq_file *seq, void *v) return 0; } +static int __maybe_unused cgroup_extra_stat_show(struct seq_file *seq, + struct cgroup *cgrp, int ssid) +{ + struct cgroup_subsys *ss = cgroup_subsys[ssid]; + struct cgroup_subsys_state *css; + int ret; + + if (!ss->css_extra_stat_show) + return 0; + + css = cgroup_tryget_css(cgrp, ss); + if (!css) + return 0; + + ret = ss->css_extra_stat_show(seq, css); + css_put(css); + return ret; +} + +static int cpu_stat_show(struct seq_file *seq, void *v) +{ + struct cgroup __maybe_unused *cgrp = seq_css(seq)->cgroup; + int ret = 0; + + cgroup_stat_show_cputime(seq); +#ifdef CONFIG_CGROUP_SCHED + ret = cgroup_extra_stat_show(seq, cgrp, cpu_cgrp_id); +#endif + return ret; +} + static int cgroup_file_open(struct kernfs_open_file *of) { struct cftype *cft = of->kn->priv; @@ -4422,6 +4485,11 @@ static struct cftype cgroup_base_files[] = { .name = "cgroup.stat", .seq_show = cgroup_stat_show, }, + { + .name = "cpu.stat", + .flags = CFTYPE_NOT_ON_ROOT, + .seq_show = cpu_stat_show, + }, { } /* terminate */ }; @@ -4482,6 +4550,8 @@ static void css_free_work_fn(struct work_struct *work) */ cgroup_put(cgroup_parent(cgrp)); kernfs_put(cgrp->kn); + if (cgroup_on_dfl(cgrp)) + cgroup_stat_exit(cgrp); kfree(cgrp); } else { /* @@ -4526,6 +4596,9 @@ static void css_release_work_fn(struct work_struct *work) /* cgroup release path */ trace_cgroup_release(cgrp); + if (cgroup_on_dfl(cgrp)) + cgroup_stat_flush(cgrp); + for (tcgrp = cgroup_parent(cgrp); tcgrp; tcgrp = cgroup_parent(tcgrp)) tcgrp->nr_dying_descendants--; @@ -4709,6 +4782,12 @@ static struct cgroup *cgroup_create(struct cgroup *parent) if (ret) goto out_free_cgrp; + if (cgroup_on_dfl(parent)) { + ret = cgroup_stat_init(cgrp); + if (ret) + goto out_cancel_ref; + } + /* * Temporarily set the pointer to NULL, so idr_find() won't return * a half-baked cgroup. @@ -4716,7 +4795,7 @@ static struct cgroup *cgroup_create(struct cgroup *parent) cgrp->id = cgroup_idr_alloc(&root->cgroup_idr, NULL, 2, 0, GFP_KERNEL); if (cgrp->id < 0) { ret = -ENOMEM; - goto out_cancel_ref; + goto out_stat_exit; } init_cgroup_housekeeping(cgrp); @@ -4767,6 +4846,9 @@ static struct cgroup *cgroup_create(struct cgroup *parent) out_idr_free: cgroup_idr_remove(&root->cgroup_idr, cgrp->id); +out_stat_exit: + if (cgroup_on_dfl(parent)) + cgroup_stat_exit(cgrp); out_cancel_ref: percpu_ref_exit(&cgrp->self.refcnt); out_free_cgrp: @@ -5161,6 +5243,8 @@ 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(); + /* * The latency of the synchronize_sched() is too high for cgroups, * avoid it at the cost of forcing all readers into the slow path. @@ -5780,3 +5864,72 @@ int cgroup_bpf_query(struct cgroup *cgrp, const union bpf_attr *attr, return ret; } #endif /* CONFIG_CGROUP_BPF */ + +#ifdef CONFIG_SYSFS +static ssize_t show_delegatable_files(struct cftype *files, char *buf, + ssize_t size, const char *prefix) +{ + struct cftype *cft; + ssize_t ret = 0; + + for (cft = files; cft && cft->name[0] != '\0'; cft++) { + if (!(cft->flags & CFTYPE_NS_DELEGATABLE)) + continue; + + if (prefix) + ret += snprintf(buf + ret, size - ret, "%s.", prefix); + + ret += snprintf(buf + ret, size - ret, "%s\n", cft->name); + + if (unlikely(ret >= size)) { + WARN_ON(1); + break; + } + } + + return ret; +} + +static ssize_t delegate_show(struct kobject *kobj, struct kobj_attribute *attr, + char *buf) +{ + struct cgroup_subsys *ss; + int ssid; + ssize_t ret = 0; + + ret = show_delegatable_files(cgroup_base_files, buf, PAGE_SIZE - ret, + NULL); + + for_each_subsys(ss, ssid) + ret += show_delegatable_files(ss->dfl_cftypes, buf + ret, + PAGE_SIZE - ret, + cgroup_subsys_name[ssid]); + + return ret; +} +static struct kobj_attribute cgroup_delegate_attr = __ATTR_RO(delegate); + +static ssize_t features_show(struct kobject *kobj, struct kobj_attribute *attr, + char *buf) +{ + return snprintf(buf, PAGE_SIZE, "nsdelegate\n"); +} +static struct kobj_attribute cgroup_features_attr = __ATTR_RO(features); + +static struct attribute *cgroup_sysfs_attrs[] = { + &cgroup_delegate_attr.attr, + &cgroup_features_attr.attr, + NULL, +}; + +static const struct attribute_group cgroup_sysfs_attr_group = { + .attrs = cgroup_sysfs_attrs, + .name = "cgroup", +}; + +static int __init cgroup_sysfs_init(void) +{ + return sysfs_create_group(kernel_kobj, &cgroup_sysfs_attr_group); +} +subsys_initcall(cgroup_sysfs_init); +#endif /* CONFIG_SYSFS */ diff --git a/kernel/cgroup/stat.c b/kernel/cgroup/stat.c new file mode 100644 index 0000000..133b465 --- /dev/null +++ b/kernel/cgroup/stat.c @@ -0,0 +1,334 @@ +#include "cgroup-internal.h" + +#include <linux/sched/cputime.h> + +static DEFINE_MUTEX(cgroup_stat_mutex); +static DEFINE_PER_CPU(raw_spinlock_t, cgroup_cpu_stat_lock); + +static struct cgroup_cpu_stat *cgroup_cpu_stat(struct cgroup *cgrp, int cpu) +{ + return per_cpu_ptr(cgrp->cpu_stat, cpu); +} + +/** + * cgroup_cpu_stat_updated - keep track of updated cpu_stat + * @cgrp: target cgroup + * @cpu: cpu on which cpu_stat 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. + */ +static void cgroup_cpu_stat_updated(struct cgroup *cgrp, int cpu) +{ + raw_spinlock_t *cpu_lock = per_cpu_ptr(&cgroup_cpu_stat_lock, cpu); + struct cgroup *parent; + unsigned long flags; + + /* + * Speculative already-on-list test. This may race leading to + * temporary inaccuracies, which is fine. + * + * Because @parent's updated_children is terminated with @parent + * 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) + return; + + raw_spin_lock_irqsave(cpu_lock, flags); + + /* 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); + + /* + * Both additions and removals are bottom-up. If a cgroup + * is already in the tree, all ancestors are. + */ + if (cstat->updated_next) + break; + + cstat->updated_next = pcstat->updated_children; + pcstat->updated_children = cgrp; + } + + raw_spin_unlock_irqrestore(cpu_lock, flags); +} + +/** + * cgroup_cpu_stat_pop_updated - iterate and dismantle cpu_stat 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 + * 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. + * + * 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) +{ + struct cgroup_cpu_stat *cstat; + struct cgroup *parent; + + if (pos == root) + return NULL; + + /* + * We're gonna walk down to the first leaf and visit/remove it. We + * can pick whatever unvisited node as the starting point. + */ + if (!pos) + pos = root; + else + pos = cgroup_parent(pos); + + /* walk down to the first leaf */ + while (true) { + cstat = cgroup_cpu_stat(pos, cpu); + if (cstat->updated_children == pos) + break; + pos = cstat->updated_children; + } + + /* + * Unlink @pos from the tree. As the updated_children list is + * singly linked, we have to walk it to find the removal point. + * However, due to the way we traverse, @pos will be the first + * 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; + struct cgroup **nextp; + + nextp = &pcstat->updated_children; + while (true) { + ncstat = cgroup_cpu_stat(*nextp, cpu); + if (*nextp == pos) + break; + + WARN_ON_ONCE(*nextp == parent); + nextp = &ncstat->updated_next; + } + + *nextp = cstat->updated_next; + cstat->updated_next = NULL; + } + + return pos; +} + +static void cgroup_stat_accumulate(struct cgroup_stat *dst_stat, + struct cgroup_stat *src_stat) +{ + dst_stat->cputime.utime += src_stat->cputime.utime; + dst_stat->cputime.stime += src_stat->cputime.stime; + dst_stat->cputime.sum_exec_runtime += src_stat->cputime.sum_exec_runtime; +} + +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 task_cputime cputime; + struct cgroup_stat delta; + unsigned seq; + + lockdep_assert_held(&cgroup_stat_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)); + + /* accumulate the deltas to propgate */ + delta.cputime.utime = cputime.utime - last_cputime->utime; + delta.cputime.stime = cputime.stime - last_cputime->stime; + delta.cputime.sum_exec_runtime = cputime.sum_exec_runtime - + last_cputime->sum_exec_runtime; + *last_cputime = cputime; + + /* transfer the pending stat into delta */ + cgroup_stat_accumulate(&delta, &cgrp->pending_stat); + memset(&cgrp->pending_stat, 0, sizeof(cgrp->pending_stat)); + + /* propagate delta into the global stat and the parent's pending */ + cgroup_stat_accumulate(&cgrp->stat, &delta); + if (parent) + cgroup_stat_accumulate(&parent->pending_stat, &delta); +} + +/* see cgroup_stat_flush() */ +static void cgroup_stat_flush_locked(struct cgroup *cgrp) +{ + int cpu; + + lockdep_assert_held(&cgroup_stat_mutex); + + for_each_possible_cpu(cpu) { + raw_spinlock_t *cpu_lock = per_cpu_ptr(&cgroup_cpu_stat_lock, cpu); + struct cgroup *pos = NULL; + + raw_spin_lock_irq(cpu_lock); + while ((pos = cgroup_cpu_stat_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 + * @cgrp: target cgroup + * + * Collect all per-cpu stats in @cgrp's subtree into the global counters + * and propagate them upwards. After this function returns, all cgroups in + * the subtree have up-to-date ->stat. + * + * This also gets all cgroups in the subtree including @cgrp off the + * ->updated_children lists. + */ +void cgroup_stat_flush(struct cgroup *cgrp) +{ + mutex_lock(&cgroup_stat_mutex); + cgroup_stat_flush_locked(cgrp); + mutex_unlock(&cgroup_stat_mutex); +} + +static struct cgroup_cpu_stat *cgroup_cpu_stat_account_begin(struct cgroup *cgrp) +{ + struct cgroup_cpu_stat *cstat; + + cstat = get_cpu_ptr(cgrp->cpu_stat); + u64_stats_update_begin(&cstat->sync); + return cstat; +} + +static void cgroup_cpu_stat_account_end(struct cgroup *cgrp, + struct cgroup_cpu_stat *cstat) +{ + u64_stats_update_end(&cstat->sync); + cgroup_cpu_stat_updated(cgrp, smp_processor_id()); + put_cpu_ptr(cstat); +} + +void __cgroup_account_cputime(struct cgroup *cgrp, u64 delta_exec) +{ + struct cgroup_cpu_stat *cstat; + + cstat = cgroup_cpu_stat_account_begin(cgrp); + cstat->cputime.sum_exec_runtime += delta_exec; + cgroup_cpu_stat_account_end(cgrp, cstat); +} + +void __cgroup_account_cputime_field(struct cgroup *cgrp, + enum cpu_usage_stat index, u64 delta_exec) +{ + struct cgroup_cpu_stat *cstat; + + cstat = cgroup_cpu_stat_account_begin(cgrp); + + switch (index) { + case CPUTIME_USER: + case CPUTIME_NICE: + cstat->cputime.utime += delta_exec; + break; + case CPUTIME_SYSTEM: + case CPUTIME_IRQ: + case CPUTIME_SOFTIRQ: + cstat->cputime.stime += delta_exec; + break; + default: + break; + } + + cgroup_cpu_stat_account_end(cgrp, cstat); +} + +void cgroup_stat_show_cputime(struct seq_file *seq) +{ + struct cgroup *cgrp = seq_css(seq)->cgroup; + u64 usage, utime, stime; + + if (!cgroup_parent(cgrp)) + return; + + mutex_lock(&cgroup_stat_mutex); + + cgroup_stat_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); + + do_div(usage, NSEC_PER_USEC); + do_div(utime, NSEC_PER_USEC); + do_div(stime, NSEC_PER_USEC); + + seq_printf(seq, "usage_usec %llu\n" + "user_usec %llu\n" + "system_usec %llu\n", + usage, utime, stime); +} + +int cgroup_stat_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) + return -ENOMEM; + } + + /* ->updated_children list is self terminated */ + for_each_possible_cpu(cpu) + cgroup_cpu_stat(cgrp, cpu)->updated_children = cgrp; + + prev_cputime_init(&cgrp->stat.prev_cputime); + + return 0; +} + +void cgroup_stat_exit(struct cgroup *cgrp) +{ + int cpu; + + cgroup_stat_flush(cgrp); + + /* sanity check */ + for_each_possible_cpu(cpu) { + struct cgroup_cpu_stat *cstat = cgroup_cpu_stat(cgrp, cpu); + + if (WARN_ON_ONCE(cstat->updated_children != cgrp) || + WARN_ON_ONCE(cstat->updated_next)) + return; + } + + free_percpu(cgrp->cpu_stat); + cgrp->cpu_stat = NULL; +} + +void __init cgroup_stat_boot(void) +{ + int cpu; + + for_each_possible_cpu(cpu) + raw_spin_lock_init(per_cpu_ptr(&cgroup_cpu_stat_lock, cpu)); + + BUG_ON(cgroup_stat_init(&cgrp_dfl_root.cgrp)); +} diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 5b82a00..a092f35 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -6620,7 +6620,7 @@ static int __cfs_schedulable(struct task_group *tg, u64 period, u64 quota) return ret; } -static int cpu_stats_show(struct seq_file *sf, void *v) +static int cpu_cfs_stat_show(struct seq_file *sf, void *v) { struct task_group *tg = css_tg(seq_css(sf)); struct cfs_bandwidth *cfs_b = &tg->cfs_bandwidth; @@ -6660,7 +6660,7 @@ static u64 cpu_rt_period_read_uint(struct cgroup_subsys_state *css, } #endif /* CONFIG_RT_GROUP_SCHED */ -static struct cftype cpu_files[] = { +static struct cftype cpu_legacy_files[] = { #ifdef CONFIG_FAIR_GROUP_SCHED { .name = "shares", @@ -6681,7 +6681,7 @@ static struct cftype cpu_files[] = { }, { .name = "stat", - .seq_show = cpu_stats_show, + .seq_show = cpu_cfs_stat_show, }, #endif #ifdef CONFIG_RT_GROUP_SCHED @@ -6699,16 +6699,182 @@ static struct cftype cpu_files[] = { { } /* Terminate */ }; +static int cpu_extra_stat_show(struct seq_file *sf, + struct cgroup_subsys_state *css) +{ +#ifdef CONFIG_CFS_BANDWIDTH + { + struct task_group *tg = css_tg(css); + struct cfs_bandwidth *cfs_b = &tg->cfs_bandwidth; + u64 throttled_usec; + + throttled_usec = cfs_b->throttled_time; + do_div(throttled_usec, NSEC_PER_USEC); + + seq_printf(sf, "nr_periods %d\n" + "nr_throttled %d\n" + "throttled_usec %llu\n", + cfs_b->nr_periods, cfs_b->nr_throttled, + throttled_usec); + } +#endif + return 0; +} + +#ifdef CONFIG_FAIR_GROUP_SCHED +static u64 cpu_weight_read_u64(struct cgroup_subsys_state *css, + struct cftype *cft) +{ + struct task_group *tg = css_tg(css); + u64 weight = scale_load_down(tg->shares); + + return DIV_ROUND_CLOSEST_ULL(weight * CGROUP_WEIGHT_DFL, 1024); +} + +static int cpu_weight_write_u64(struct cgroup_subsys_state *css, + struct cftype *cft, u64 weight) +{ + /* + * cgroup weight knobs should use the common MIN, DFL and MAX + * values which are 1, 100 and 10000 respectively. While it loses + * a bit of range on both ends, it maps pretty well onto the shares + * value used by scheduler and the round-trip conversions preserve + * the original value over the entire range. + */ + if (weight < CGROUP_WEIGHT_MIN || weight > CGROUP_WEIGHT_MAX) + return -ERANGE; + + weight = DIV_ROUND_CLOSEST_ULL(weight * 1024, CGROUP_WEIGHT_DFL); + + return sched_group_set_shares(css_tg(css), scale_load(weight)); +} + +static s64 cpu_weight_nice_read_s64(struct cgroup_subsys_state *css, + struct cftype *cft) +{ + unsigned long weight = scale_load_down(css_tg(css)->shares); + int last_delta = INT_MAX; + int prio, delta; + + /* find the closest nice value to the current weight */ + for (prio = 0; prio < ARRAY_SIZE(sched_prio_to_weight); prio++) { + delta = abs(sched_prio_to_weight[prio] - weight); + if (delta >= last_delta) + break; + last_delta = delta; + } + + return PRIO_TO_NICE(prio - 1 + MAX_RT_PRIO); +} + +static int cpu_weight_nice_write_s64(struct cgroup_subsys_state *css, + struct cftype *cft, s64 nice) +{ + unsigned long weight; + + if (nice < MIN_NICE || nice > MAX_NICE) + return -ERANGE; + + weight = sched_prio_to_weight[NICE_TO_PRIO(nice) - MAX_RT_PRIO]; + return sched_group_set_shares(css_tg(css), scale_load(weight)); +} +#endif + +static void __maybe_unused cpu_period_quota_print(struct seq_file *sf, + long period, long quota) +{ + if (quota < 0) + seq_puts(sf, "max"); + else + seq_printf(sf, "%ld", quota); + + seq_printf(sf, " %ld\n", period); +} + +/* caller should put the current value in *@periodp before calling */ +static int __maybe_unused cpu_period_quota_parse(char *buf, + u64 *periodp, u64 *quotap) +{ + char tok[21]; /* U64_MAX */ + + if (!sscanf(buf, "%s %llu", tok, periodp)) + return -EINVAL; + + *periodp *= NSEC_PER_USEC; + + if (sscanf(tok, "%llu", quotap)) + *quotap *= NSEC_PER_USEC; + else if (!strcmp(tok, "max")) + *quotap = RUNTIME_INF; + else + return -EINVAL; + + return 0; +} + +#ifdef CONFIG_CFS_BANDWIDTH +static int cpu_max_show(struct seq_file *sf, void *v) +{ + struct task_group *tg = css_tg(seq_css(sf)); + + cpu_period_quota_print(sf, tg_get_cfs_period(tg), tg_get_cfs_quota(tg)); + return 0; +} + +static ssize_t cpu_max_write(struct kernfs_open_file *of, + char *buf, size_t nbytes, loff_t off) +{ + struct task_group *tg = css_tg(of_css(of)); + u64 period = tg_get_cfs_period(tg); + u64 quota; + int ret; + + ret = cpu_period_quota_parse(buf, &period, "a); + if (!ret) + ret = tg_set_cfs_bandwidth(tg, period, quota); + return ret ?: nbytes; +} +#endif + +static struct cftype cpu_files[] = { +#ifdef CONFIG_FAIR_GROUP_SCHED + { + .name = "weight", + .flags = CFTYPE_NOT_ON_ROOT, + .read_u64 = cpu_weight_read_u64, + .write_u64 = cpu_weight_write_u64, + }, + { + .name = "weight.nice", + .flags = CFTYPE_NOT_ON_ROOT, + .read_s64 = cpu_weight_nice_read_s64, + .write_s64 = cpu_weight_nice_write_s64, + }, +#endif +#ifdef CONFIG_CFS_BANDWIDTH + { + .name = "max", + .flags = CFTYPE_NOT_ON_ROOT, + .seq_show = cpu_max_show, + .write = cpu_max_write, + }, +#endif + { } /* terminate */ +}; + struct cgroup_subsys cpu_cgrp_subsys = { .css_alloc = cpu_cgroup_css_alloc, .css_online = cpu_cgroup_css_online, .css_released = cpu_cgroup_css_released, .css_free = cpu_cgroup_css_free, + .css_extra_stat_show = cpu_extra_stat_show, .fork = cpu_cgroup_fork, .can_attach = cpu_cgroup_can_attach, .attach = cpu_cgroup_attach, - .legacy_cftypes = cpu_files, + .legacy_cftypes = cpu_legacy_files, + .dfl_cftypes = cpu_files, .early_init = true, + .threaded = true, }; #endif /* CONFIG_CGROUP_SCHED */ diff --git a/kernel/sched/cpuacct.h b/kernel/sched/cpuacct.h deleted file mode 100644 index a8358a5..0000000 --- a/kernel/sched/cpuacct.h +++ /dev/null @@ -1,18 +0,0 @@ -/* SPDX-License-Identifier: GPL-2.0 */ -#ifdef CONFIG_CGROUP_CPUACCT - -extern void cpuacct_charge(struct task_struct *tsk, u64 cputime); -extern void cpuacct_account_field(struct task_struct *tsk, int index, u64 val); - -#else - -static inline void cpuacct_charge(struct task_struct *tsk, u64 cputime) -{ -} - -static inline void -cpuacct_account_field(struct task_struct *tsk, int index, u64 val) -{ -} - -#endif diff --git a/kernel/sched/cputime.c b/kernel/sched/cputime.c index 9be8b68..bac6ac9 100644 --- a/kernel/sched/cputime.c +++ b/kernel/sched/cputime.c @@ -109,7 +109,7 @@ static inline void task_group_account_field(struct task_struct *p, int index, */ __this_cpu_add(kernel_cpustat.cpustat[index], tmp); - cpuacct_account_field(p, index, tmp); + cgroup_account_cputime_field(p, index, tmp); } /* @@ -446,6 +446,13 @@ void vtime_account_irq_enter(struct task_struct *tsk) EXPORT_SYMBOL_GPL(vtime_account_irq_enter); #endif /* __ARCH_HAS_VTIME_ACCOUNT */ +void cputime_adjust(struct task_cputime *curr, struct prev_cputime *prev, + u64 *ut, u64 *st) +{ + *ut = curr->utime; + *st = curr->stime; +} + void task_cputime_adjusted(struct task_struct *p, u64 *ut, u64 *st) { *ut = p->utime; @@ -584,9 +591,8 @@ drop_precision: * * Assuming that rtime_i+1 >= rtime_i. */ -static void cputime_adjust(struct task_cputime *curr, - struct prev_cputime *prev, - u64 *ut, u64 *st) +void cputime_adjust(struct task_cputime *curr, struct prev_cputime *prev, + u64 *ut, u64 *st) { u64 rtime, stime, utime; unsigned long flags; diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c index f349f7e..2473736 100644 --- a/kernel/sched/deadline.c +++ b/kernel/sched/deadline.c @@ -1144,7 +1144,7 @@ static void update_curr_dl(struct rq *rq) account_group_exec_runtime(curr, delta_exec); curr->se.exec_start = rq_clock_task(rq); - cpuacct_charge(curr, delta_exec); + cgroup_account_cputime(curr, delta_exec); sched_rt_avg_update(rq, delta_exec); diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 0989676..4037e19 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -844,7 +844,7 @@ static void update_curr(struct cfs_rq *cfs_rq) struct task_struct *curtask = task_of(curr); trace_sched_stat_runtime(curtask, delta_exec, curr->vruntime); - cpuacct_charge(curtask, delta_exec); + cgroup_account_cputime(curtask, delta_exec); account_group_exec_runtime(curtask, delta_exec); } diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c index d8c43d7..4056c19 100644 --- a/kernel/sched/rt.c +++ b/kernel/sched/rt.c @@ -969,7 +969,7 @@ static void update_curr_rt(struct rq *rq) account_group_exec_runtime(curr, delta_exec); curr->se.exec_start = rq_clock_task(rq); - cpuacct_charge(curr, delta_exec); + cgroup_account_cputime(curr, delta_exec); sched_rt_avg_update(rq, delta_exec); diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h index 45ab0bf..b19552a2 100644 --- a/kernel/sched/sched.h +++ b/kernel/sched/sched.h @@ -30,6 +30,7 @@ #include <linux/irq_work.h> #include <linux/tick.h> #include <linux/slab.h> +#include <linux/cgroup.h> #ifdef CONFIG_PARAVIRT #include <asm/paravirt.h> @@ -37,7 +38,6 @@ #include "cpupri.h" #include "cpudeadline.h" -#include "cpuacct.h" #ifdef CONFIG_SCHED_DEBUG # define SCHED_WARN_ON(x) WARN_ONCE(x, #x) diff --git a/kernel/sched/stop_task.c b/kernel/sched/stop_task.c index 45caf90..210b1f2 100644 --- a/kernel/sched/stop_task.c +++ b/kernel/sched/stop_task.c @@ -72,7 +72,7 @@ static void put_prev_task_stop(struct rq *rq, struct task_struct *prev) account_group_exec_runtime(curr, delta_exec); curr->se.exec_start = rq_clock_task(rq); - cpuacct_charge(curr, delta_exec); + cgroup_account_cputime(curr, delta_exec); } static void task_tick_stop(struct rq *rq, struct task_struct *curr, int queued) |
