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()

8 files changed, 185 insertions, 31 deletions

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)