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authorLinus Torvalds <torvalds@linux-foundation.org>2017-11-15 14:29:44 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2017-11-15 14:29:44 -0800
commit22714a2ba4b55737cd7d5299db7aaf1fa8287354 (patch)
tree32b25f2e3e40732156a8a8d0dcb2ddf38410776f
parent766ec76a27aa9dfdfee3a80f29ddc1f7539c71f9 (diff)
parent5f2e673405b742be64e7c3604ed4ed3ac14f35ce (diff)
Merge branch 'for-4.15' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup
Pull cgroup updates from Tejun Heo: "Cgroup2 cpu controller support is finally merged. - Basic cpu statistics support to allow monitoring by default without the CPU controller enabled. - cgroup2 cpu controller support. - /sys/kernel/cgroup files to help dealing with new / optional features" * 'for-4.15' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: cgroup: export list of cgroups v2 features using sysfs cgroup: export list of delegatable control files using sysfs cgroup: mark @cgrp __maybe_unused in cpu_stat_show() MAINTAINERS: relocate cpuset.c cgroup, sched: Move basic cpu stats from cgroup.stat to cpu.stat sched: Implement interface for cgroup unified hierarchy sched: Misc preps for cgroup unified hierarchy interface sched/cputime: Add dummy cputime_adjust() implementation for CONFIG_VIRT_CPU_ACCOUNTING_NATIVE cgroup: statically initialize init_css_set->dfl_cgrp cgroup: Implement cgroup2 basic CPU usage accounting cpuacct: Introduce cgroup_account_cputime[_field]() sched/cputime: Expose cputime_adjust()
-rw-r--r--Documentation/cgroup-v2.txt42
-rw-r--r--MAINTAINERS2
-rw-r--r--include/linux/cgroup-defs.h59
-rw-r--r--include/linux/cgroup.h58
-rw-r--r--include/linux/sched/cputime.h3
-rw-r--r--kernel/cgroup/Makefile2
-rw-r--r--kernel/cgroup/cgroup-internal.h9
-rw-r--r--kernel/cgroup/cgroup.c157
-rw-r--r--kernel/cgroup/stat.c334
-rw-r--r--kernel/sched/core.c174
-rw-r--r--kernel/sched/cpuacct.h18
-rw-r--r--kernel/sched/cputime.c14
-rw-r--r--kernel/sched/deadline.c2
-rw-r--r--kernel/sched/fair.c2
-rw-r--r--kernel/sched/rt.c2
-rw-r--r--kernel/sched/sched.h2
-rw-r--r--kernel/sched/stop_task.c2
17 files changed, 821 insertions, 61 deletions
diff --git a/Documentation/cgroup-v2.txt b/Documentation/cgroup-v2.txt
index dc44785dc0fa..779211fbb69f 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 16e1e6dc89f2..a74d6a738864 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 1dff0a478b45..8b7fd8eeccee 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 dddbc29e2009..473e0c0abb86 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 d0677f6739f6..53f883f5a2fd 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 ae448f7632cc..2be89a003185 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 bf54ade001be..b928b27050c6 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 00f5b358aeac..0b1ffe147f24 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 000000000000..133b465691d6
--- /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 5b82a0073532..a092f350f3a2 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, &quota);
+ 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 a8358a57a316..000000000000
--- 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 9be8b68a66da..bac6ac9a4ec7 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 f349f7e98dec..2473736c7616 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 0989676c50e9..4037e19bbca2 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 d8c43d73e078..4056c19ca3f0 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 45ab0bf564e7..b19552a212de 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 45caf90b24cd..210b1f2146ff 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)