cgroup: move cgroup files under kernel/cgroup/

They're growing to be too many and planned to get split further.  Move
them under their own directory.

 kernel/cgroup.c		-> kernel/cgroup/cgroup.c
 kernel/cgroup_freezer.c	-> kernel/cgroup/freezer.c
 kernel/cgroup_pids.c		-> kernel/cgroup/pids.c
 kernel/cpuset.c		-> kernel/cgroup/cpuset.c

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Acked-by: Zefan Li <lizefan@huawei.com>

1 files changed, 0 insertions, 2752 deletions

diff --git a/kernel/cpuset.c b/kernel/cpuset.c
deleted file mode 100644
index b3088886cd37..000000000000
--- a/kernel/cpuset.c
+++ /dev/null
@@ -1,2752 +0,0 @@
-/*
- *  kernel/cpuset.c
- *
- *  Processor and Memory placement constraints for sets of tasks.
- *
- *  Copyright (C) 2003 BULL SA.
- *  Copyright (C) 2004-2007 Silicon Graphics, Inc.
- *  Copyright (C) 2006 Google, Inc
- *
- *  Portions derived from Patrick Mochel's sysfs code.
- *  sysfs is Copyright (c) 2001-3 Patrick Mochel
- *
- *  2003-10-10 Written by Simon Derr.
- *  2003-10-22 Updates by Stephen Hemminger.
- *  2004 May-July Rework by Paul Jackson.
- *  2006 Rework by Paul Menage to use generic cgroups
- *  2008 Rework of the scheduler domains and CPU hotplug handling
- *       by Max Krasnyansky
- *
- *  This file is subject to the terms and conditions of the GNU General Public
- *  License.  See the file COPYING in the main directory of the Linux
- *  distribution for more details.
- */
-
-#include <linux/cpu.h>
-#include <linux/cpumask.h>
-#include <linux/cpuset.h>
-#include <linux/err.h>
-#include <linux/errno.h>
-#include <linux/file.h>
-#include <linux/fs.h>
-#include <linux/init.h>
-#include <linux/interrupt.h>
-#include <linux/kernel.h>
-#include <linux/kmod.h>
-#include <linux/list.h>
-#include <linux/mempolicy.h>
-#include <linux/mm.h>
-#include <linux/memory.h>
-#include <linux/export.h>
-#include <linux/mount.h>
-#include <linux/namei.h>
-#include <linux/pagemap.h>
-#include <linux/proc_fs.h>
-#include <linux/rcupdate.h>
-#include <linux/sched.h>
-#include <linux/seq_file.h>
-#include <linux/security.h>
-#include <linux/slab.h>
-#include <linux/spinlock.h>
-#include <linux/stat.h>
-#include <linux/string.h>
-#include <linux/time.h>
-#include <linux/time64.h>
-#include <linux/backing-dev.h>
-#include <linux/sort.h>
-
-#include <linux/uaccess.h>
-#include <linux/atomic.h>
-#include <linux/mutex.h>
-#include <linux/cgroup.h>
-#include <linux/wait.h>
-
-DEFINE_STATIC_KEY_FALSE(cpusets_enabled_key);
-
-/* See "Frequency meter" comments, below. */
-
-struct fmeter {
-	int cnt;		/* unprocessed events count */
-	int val;		/* most recent output value */
-	time64_t time;		/* clock (secs) when val computed */
-	spinlock_t lock;	/* guards read or write of above */
-};
-
-struct cpuset {
-	struct cgroup_subsys_state css;
-
-	unsigned long flags;		/* "unsigned long" so bitops work */
-
-	/*
-	 * On default hierarchy:
-	 *
-	 * The user-configured masks can only be changed by writing to
-	 * cpuset.cpus and cpuset.mems, and won't be limited by the
-	 * parent masks.
-	 *
-	 * The effective masks is the real masks that apply to the tasks
-	 * in the cpuset. They may be changed if the configured masks are
-	 * changed or hotplug happens.
-	 *
-	 * effective_mask == configured_mask & parent's effective_mask,
-	 * and if it ends up empty, it will inherit the parent's mask.
-	 *
-	 *
-	 * On legacy hierachy:
-	 *
-	 * The user-configured masks are always the same with effective masks.
-	 */
-
-	/* user-configured CPUs and Memory Nodes allow to tasks */
-	cpumask_var_t cpus_allowed;
-	nodemask_t mems_allowed;
-
-	/* effective CPUs and Memory Nodes allow to tasks */
-	cpumask_var_t effective_cpus;
-	nodemask_t effective_mems;
-
-	/*
-	 * This is old Memory Nodes tasks took on.
-	 *
-	 * - top_cpuset.old_mems_allowed is initialized to mems_allowed.
-	 * - A new cpuset's old_mems_allowed is initialized when some
-	 *   task is moved into it.
-	 * - old_mems_allowed is used in cpuset_migrate_mm() when we change
-	 *   cpuset.mems_allowed and have tasks' nodemask updated, and
-	 *   then old_mems_allowed is updated to mems_allowed.
-	 */
-	nodemask_t old_mems_allowed;
-
-	struct fmeter fmeter;		/* memory_pressure filter */
-
-	/*
-	 * Tasks are being attached to this cpuset.  Used to prevent
-	 * zeroing cpus/mems_allowed between ->can_attach() and ->attach().
-	 */
-	int attach_in_progress;
-
-	/* partition number for rebuild_sched_domains() */
-	int pn;
-
-	/* for custom sched domain */
-	int relax_domain_level;
-};
-
-static inline struct cpuset *css_cs(struct cgroup_subsys_state *css)
-{
-	return css ? container_of(css, struct cpuset, css) : NULL;
-}
-
-/* Retrieve the cpuset for a task */
-static inline struct cpuset *task_cs(struct task_struct *task)
-{
-	return css_cs(task_css(task, cpuset_cgrp_id));
-}
-
-static inline struct cpuset *parent_cs(struct cpuset *cs)
-{
-	return css_cs(cs->css.parent);
-}
-
-#ifdef CONFIG_NUMA
-static inline bool task_has_mempolicy(struct task_struct *task)
-{
-	return task->mempolicy;
-}
-#else
-static inline bool task_has_mempolicy(struct task_struct *task)
-{
-	return false;
-}
-#endif
-
-
-/* bits in struct cpuset flags field */
-typedef enum {
-	CS_ONLINE,
-	CS_CPU_EXCLUSIVE,
-	CS_MEM_EXCLUSIVE,
-	CS_MEM_HARDWALL,
-	CS_MEMORY_MIGRATE,
-	CS_SCHED_LOAD_BALANCE,
-	CS_SPREAD_PAGE,
-	CS_SPREAD_SLAB,
-} cpuset_flagbits_t;
-
-/* convenient tests for these bits */
-static inline bool is_cpuset_online(const struct cpuset *cs)
-{
-	return test_bit(CS_ONLINE, &cs->flags);
-}
-
-static inline int is_cpu_exclusive(const struct cpuset *cs)
-{
-	return test_bit(CS_CPU_EXCLUSIVE, &cs->flags);
-}
-
-static inline int is_mem_exclusive(const struct cpuset *cs)
-{
-	return test_bit(CS_MEM_EXCLUSIVE, &cs->flags);
-}
-
-static inline int is_mem_hardwall(const struct cpuset *cs)
-{
-	return test_bit(CS_MEM_HARDWALL, &cs->flags);
-}
-
-static inline int is_sched_load_balance(const struct cpuset *cs)
-{
-	return test_bit(CS_SCHED_LOAD_BALANCE, &cs->flags);
-}
-
-static inline int is_memory_migrate(const struct cpuset *cs)
-{
-	return test_bit(CS_MEMORY_MIGRATE, &cs->flags);
-}
-
-static inline int is_spread_page(const struct cpuset *cs)
-{
-	return test_bit(CS_SPREAD_PAGE, &cs->flags);
-}
-
-static inline int is_spread_slab(const struct cpuset *cs)
-{
-	return test_bit(CS_SPREAD_SLAB, &cs->flags);
-}
-
-static struct cpuset top_cpuset = {
-	.flags = ((1 << CS_ONLINE) | (1 << CS_CPU_EXCLUSIVE) |
-		  (1 << CS_MEM_EXCLUSIVE)),
-};
-
-/**
- * cpuset_for_each_child - traverse online children of a cpuset
- * @child_cs: loop cursor pointing to the current child
- * @pos_css: used for iteration
- * @parent_cs: target cpuset to walk children of
- *
- * Walk @child_cs through the online children of @parent_cs.  Must be used
- * with RCU read locked.
- */
-#define cpuset_for_each_child(child_cs, pos_css, parent_cs)		\
-	css_for_each_child((pos_css), &(parent_cs)->css)		\
-		if (is_cpuset_online(((child_cs) = css_cs((pos_css)))))
-
-/**
- * cpuset_for_each_descendant_pre - pre-order walk of a cpuset's descendants
- * @des_cs: loop cursor pointing to the current descendant
- * @pos_css: used for iteration
- * @root_cs: target cpuset to walk ancestor of
- *
- * Walk @des_cs through the online descendants of @root_cs.  Must be used
- * with RCU read locked.  The caller may modify @pos_css by calling
- * css_rightmost_descendant() to skip subtree.  @root_cs is included in the
- * iteration and the first node to be visited.
- */
-#define cpuset_for_each_descendant_pre(des_cs, pos_css, root_cs)	\
-	css_for_each_descendant_pre((pos_css), &(root_cs)->css)		\
-		if (is_cpuset_online(((des_cs) = css_cs((pos_css)))))
-
-/*
- * There are two global locks guarding cpuset structures - cpuset_mutex and
- * callback_lock. We also require taking task_lock() when dereferencing a
- * task's cpuset pointer. See "The task_lock() exception", at the end of this
- * comment.
- *
- * A task must hold both locks to modify cpusets.  If a task holds
- * cpuset_mutex, then it blocks others wanting that mutex, ensuring that it
- * is the only task able to also acquire callback_lock and be able to
- * modify cpusets.  It can perform various checks on the cpuset structure
- * first, knowing nothing will change.  It can also allocate memory while
- * just holding cpuset_mutex.  While it is performing these checks, various
- * callback routines can briefly acquire callback_lock to query cpusets.
- * Once it is ready to make the changes, it takes callback_lock, blocking
- * everyone else.
- *
- * Calls to the kernel memory allocator can not be made while holding
- * callback_lock, as that would risk double tripping on callback_lock
- * from one of the callbacks into the cpuset code from within
- * __alloc_pages().
- *
- * If a task is only holding callback_lock, then it has read-only
- * access to cpusets.
- *
- * Now, the task_struct fields mems_allowed and mempolicy may be changed
- * by other task, we use alloc_lock in the task_struct fields to protect
- * them.
- *
- * The cpuset_common_file_read() handlers only hold callback_lock across
- * small pieces of code, such as when reading out possibly multi-word
- * cpumasks and nodemasks.
- *
- * Accessing a task's cpuset should be done in accordance with the
- * guidelines for accessing subsystem state in kernel/cgroup.c
- */
-
-static DEFINE_MUTEX(cpuset_mutex);
-static DEFINE_SPINLOCK(callback_lock);
-
-static struct workqueue_struct *cpuset_migrate_mm_wq;
-
-/*
- * CPU / memory hotplug is handled asynchronously.
- */
-static void cpuset_hotplug_workfn(struct work_struct *work);
-static DECLARE_WORK(cpuset_hotplug_work, cpuset_hotplug_workfn);
-
-static DECLARE_WAIT_QUEUE_HEAD(cpuset_attach_wq);
-
-/*
- * This is ugly, but preserves the userspace API for existing cpuset
- * users. If someone tries to mount the "cpuset" filesystem, we
- * silently switch it to mount "cgroup" instead
- */
-static struct dentry *cpuset_mount(struct file_system_type *fs_type,
-			 int flags, const char *unused_dev_name, void *data)
-{
-	struct file_system_type *cgroup_fs = get_fs_type("cgroup");
-	struct dentry *ret = ERR_PTR(-ENODEV);
-	if (cgroup_fs) {
-		char mountopts[] =
-			"cpuset,noprefix,"
-			"release_agent=/sbin/cpuset_release_agent";
-		ret = cgroup_fs->mount(cgroup_fs, flags,
-					   unused_dev_name, mountopts);
-		put_filesystem(cgroup_fs);
-	}
-	return ret;
-}
-
-static struct file_system_type cpuset_fs_type = {
-	.name = "cpuset",
-	.mount = cpuset_mount,
-};
-
-/*
- * Return in pmask the portion of a cpusets's cpus_allowed that
- * are online.  If none are online, walk up the cpuset hierarchy
- * until we find one that does have some online cpus.
- *
- * One way or another, we guarantee to return some non-empty subset
- * of cpu_online_mask.
- *
- * Call with callback_lock or cpuset_mutex held.
- */
-static void guarantee_online_cpus(struct cpuset *cs, struct cpumask *pmask)
-{
-	while (!cpumask_intersects(cs->effective_cpus, cpu_online_mask)) {
-		cs = parent_cs(cs);
-		if (unlikely(!cs)) {
-			/*
-			 * The top cpuset doesn't have any online cpu as a
-			 * consequence of a race between cpuset_hotplug_work
-			 * and cpu hotplug notifier.  But we know the top
-			 * cpuset's effective_cpus is on its way to to be
-			 * identical to cpu_online_mask.
-			 */
-			cpumask_copy(pmask, cpu_online_mask);
-			return;
-		}
-	}
-	cpumask_and(pmask, cs->effective_cpus, cpu_online_mask);
-}
-
-/*
- * Return in *pmask the portion of a cpusets's mems_allowed that
- * are online, with memory.  If none are online with memory, walk
- * up the cpuset hierarchy until we find one that does have some
- * online mems.  The top cpuset always has some mems online.
- *
- * One way or another, we guarantee to return some non-empty subset
- * of node_states[N_MEMORY].
- *
- * Call with callback_lock or cpuset_mutex held.
- */
-static void guarantee_online_mems(struct cpuset *cs, nodemask_t *pmask)
-{
-	while (!nodes_intersects(cs->effective_mems, node_states[N_MEMORY]))
-		cs = parent_cs(cs);
-	nodes_and(*pmask, cs->effective_mems, node_states[N_MEMORY]);
-}
-
-/*
- * update task's spread flag if cpuset's page/slab spread flag is set
- *
- * Call with callback_lock or cpuset_mutex held.
- */
-static void cpuset_update_task_spread_flag(struct cpuset *cs,
-					struct task_struct *tsk)
-{
-	if (is_spread_page(cs))
-		task_set_spread_page(tsk);
-	else
-		task_clear_spread_page(tsk);
-
-	if (is_spread_slab(cs))
-		task_set_spread_slab(tsk);
-	else
-		task_clear_spread_slab(tsk);
-}
-
-/*
- * is_cpuset_subset(p, q) - Is cpuset p a subset of cpuset q?
- *
- * One cpuset is a subset of another if all its allowed CPUs and
- * Memory Nodes are a subset of the other, and its exclusive flags
- * are only set if the other's are set.  Call holding cpuset_mutex.
- */
-
-static int is_cpuset_subset(const struct cpuset *p, const struct cpuset *q)
-{
-	return	cpumask_subset(p->cpus_allowed, q->cpus_allowed) &&
-		nodes_subset(p->mems_allowed, q->mems_allowed) &&
-		is_cpu_exclusive(p) <= is_cpu_exclusive(q) &&
-		is_mem_exclusive(p) <= is_mem_exclusive(q);
-}
-
-/**
- * alloc_trial_cpuset - allocate a trial cpuset
- * @cs: the cpuset that the trial cpuset duplicates
- */
-static struct cpuset *alloc_trial_cpuset(struct cpuset *cs)
-{
-	struct cpuset *trial;
-
-	trial = kmemdup(cs, sizeof(*cs), GFP_KERNEL);
-	if (!trial)
-		return NULL;
-
-	if (!alloc_cpumask_var(&trial->cpus_allowed, GFP_KERNEL))
-		goto free_cs;
-	if (!alloc_cpumask_var(&trial->effective_cpus, GFP_KERNEL))
-		goto free_cpus;
-
-	cpumask_copy(trial->cpus_allowed, cs->cpus_allowed);
-	cpumask_copy(trial->effective_cpus, cs->effective_cpus);
-	return trial;
-
-free_cpus:
-	free_cpumask_var(trial->cpus_allowed);
-free_cs:
-	kfree(trial);
-	return NULL;
-}
-
-/**
- * free_trial_cpuset - free the trial cpuset
- * @trial: the trial cpuset to be freed
- */
-static void free_trial_cpuset(struct cpuset *trial)
-{
-	free_cpumask_var(trial->effective_cpus);
-	free_cpumask_var(trial->cpus_allowed);
-	kfree(trial);
-}
-
-/*
- * validate_change() - Used to validate that any proposed cpuset change
- *		       follows the structural rules for cpusets.
- *
- * If we replaced the flag and mask values of the current cpuset
- * (cur) with those values in the trial cpuset (trial), would
- * our various subset and exclusive rules still be valid?  Presumes
- * cpuset_mutex held.
- *
- * 'cur' is the address of an actual, in-use cpuset.  Operations
- * such as list traversal that depend on the actual address of the
- * cpuset in the list must use cur below, not trial.
- *
- * 'trial' is the address of bulk structure copy of cur, with
- * perhaps one or more of the fields cpus_allowed, mems_allowed,
- * or flags changed to new, trial values.
- *
- * Return 0 if valid, -errno if not.
- */
-
-static int validate_change(struct cpuset *cur, struct cpuset *trial)
-{
-	struct cgroup_subsys_state *css;
-	struct cpuset *c, *par;
-	int ret;
-
-	rcu_read_lock();
-
-	/* Each of our child cpusets must be a subset of us */
-	ret = -EBUSY;
-	cpuset_for_each_child(c, css, cur)
-		if (!is_cpuset_subset(c, trial))
-			goto out;
-
-	/* Remaining checks don't apply to root cpuset */
-	ret = 0;
-	if (cur == &top_cpuset)
-		goto out;
-
-	par = parent_cs(cur);
-
-	/* On legacy hiearchy, we must be a subset of our parent cpuset. */
-	ret = -EACCES;
-	if (!cgroup_subsys_on_dfl(cpuset_cgrp_subsys) &&
-	    !is_cpuset_subset(trial, par))
-		goto out;
-
-	/*
-	 * If either I or some sibling (!= me) is exclusive, we can't
-	 * overlap
-	 */
-	ret = -EINVAL;
-	cpuset_for_each_child(c, css, par) {
-		if ((is_cpu_exclusive(trial) || is_cpu_exclusive(c)) &&
-		    c != cur &&
-		    cpumask_intersects(trial->cpus_allowed, c->cpus_allowed))
-			goto out;
-		if ((is_mem_exclusive(trial) || is_mem_exclusive(c)) &&
-		    c != cur &&
-		    nodes_intersects(trial->mems_allowed, c->mems_allowed))
-			goto out;
-	}
-
-	/*
-	 * Cpusets with tasks - existing or newly being attached - can't
-	 * be changed to have empty cpus_allowed or mems_allowed.
-	 */
-	ret = -ENOSPC;
-	if ((cgroup_is_populated(cur->css.cgroup) || cur->attach_in_progress)) {
-		if (!cpumask_empty(cur->cpus_allowed) &&
-		    cpumask_empty(trial->cpus_allowed))
-			goto out;
-		if (!nodes_empty(cur->mems_allowed) &&
-		    nodes_empty(trial->mems_allowed))
-			goto out;
-	}
-
-	/*
-	 * We can't shrink if we won't have enough room for SCHED_DEADLINE
-	 * tasks.
-	 */
-	ret = -EBUSY;
-	if (is_cpu_exclusive(cur) &&
-	    !cpuset_cpumask_can_shrink(cur->cpus_allowed,
-				       trial->cpus_allowed))
-		goto out;
-
-	ret = 0;
-out:
-	rcu_read_unlock();
-	return ret;
-}
-
-#ifdef CONFIG_SMP
-/*
- * Helper routine for generate_sched_domains().
- * Do cpusets a, b have overlapping effective cpus_allowed masks?
- */
-static int cpusets_overlap(struct cpuset *a, struct cpuset *b)
-{
-	return cpumask_intersects(a->effective_cpus, b->effective_cpus);
-}
-
-static void
-update_domain_attr(struct sched_domain_attr *dattr, struct cpuset *c)
-{
-	if (dattr->relax_domain_level < c->relax_domain_level)
-		dattr->relax_domain_level = c->relax_domain_level;
-	return;
-}
-
-static void update_domain_attr_tree(struct sched_domain_attr *dattr,
-				    struct cpuset *root_cs)
-{
-	struct cpuset *cp;
-	struct cgroup_subsys_state *pos_css;
-
-	rcu_read_lock();
-	cpuset_for_each_descendant_pre(cp, pos_css, root_cs) {
-		/* skip the whole subtree if @cp doesn't have any CPU */
-		if (cpumask_empty(cp->cpus_allowed)) {
-			pos_css = css_rightmost_descendant(pos_css);
-			continue;
-		}
-
-		if (is_sched_load_balance(cp))
-			update_domain_attr(dattr, cp);
-	}
-	rcu_read_unlock();
-}
-
-/*
- * generate_sched_domains()
- *
- * This function builds a partial partition of the systems CPUs
- * A 'partial partition' is a set of non-overlapping subsets whose
- * union is a subset of that set.
- * The output of this function needs to be passed to kernel/sched/core.c
- * partition_sched_domains() routine, which will rebuild the scheduler's
- * load balancing domains (sched domains) as specified by that partial
- * partition.
- *
- * See "What is sched_load_balance" in Documentation/cgroups/cpusets.txt
- * for a background explanation of this.
- *
- * Does not return errors, on the theory that the callers of this
- * routine would rather not worry about failures to rebuild sched
- * domains when operating in the severe memory shortage situations
- * that could cause allocation failures below.
- *
- * Must be called with cpuset_mutex held.
- *
- * The three key local variables below are:
- *    q  - a linked-list queue of cpuset pointers, used to implement a
- *	   top-down scan of all cpusets.  This scan loads a pointer
- *	   to each cpuset marked is_sched_load_balance into the
- *	   array 'csa'.  For our purposes, rebuilding the schedulers
- *	   sched domains, we can ignore !is_sched_load_balance cpusets.
- *  csa  - (for CpuSet Array) Array of pointers to all the cpusets
- *	   that need to be load balanced, for convenient iterative
- *	   access by the subsequent code that finds the best partition,
- *	   i.e the set of domains (subsets) of CPUs such that the
- *	   cpus_allowed of every cpuset marked is_sched_load_balance
- *	   is a subset of one of these domains, while there are as
- *	   many such domains as possible, each as small as possible.
- * doms  - Conversion of 'csa' to an array of cpumasks, for passing to
- *	   the kernel/sched/core.c routine partition_sched_domains() in a
- *	   convenient format, that can be easily compared to the prior
- *	   value to determine what partition elements (sched domains)
- *	   were changed (added or removed.)
- *
- * Finding the best partition (set of domains):
- *	The triple nested loops below over i, j, k scan over the
- *	load balanced cpusets (using the array of cpuset pointers in
- *	csa[]) looking for pairs of cpusets that have overlapping
- *	cpus_allowed, but which don't have the same 'pn' partition
- *	number and gives them in the same partition number.  It keeps
- *	looping on the 'restart' label until it can no longer find
- *	any such pairs.
- *
- *	The union of the cpus_allowed masks from the set of
- *	all cpusets having the same 'pn' value then form the one
- *	element of the partition (one sched domain) to be passed to
- *	partition_sched_domains().
- */
-static int generate_sched_domains(cpumask_var_t **domains,
-			struct sched_domain_attr **attributes)
-{
-	struct cpuset *cp;	/* scans q */
-	struct cpuset **csa;	/* array of all cpuset ptrs */
-	int csn;		/* how many cpuset ptrs in csa so far */
-	int i, j, k;		/* indices for partition finding loops */
-	cpumask_var_t *doms;	/* resulting partition; i.e. sched domains */
-	cpumask_var_t non_isolated_cpus;  /* load balanced CPUs */
-	struct sched_domain_attr *dattr;  /* attributes for custom domains */
-	int ndoms = 0;		/* number of sched domains in result */
-	int nslot;		/* next empty doms[] struct cpumask slot */
-	struct cgroup_subsys_state *pos_css;
-
-	doms = NULL;
-	dattr = NULL;
-	csa = NULL;
-
-	if (!alloc_cpumask_var(&non_isolated_cpus, GFP_KERNEL))
-		goto done;
-	cpumask_andnot(non_isolated_cpus, cpu_possible_mask, cpu_isolated_map);
-
-	/* Special case for the 99% of systems with one, full, sched domain */
-	if (is_sched_load_balance(&top_cpuset)) {
-		ndoms = 1;
-		doms = alloc_sched_domains(ndoms);
-		if (!doms)
-			goto done;
-
-		dattr = kmalloc(sizeof(struct sched_domain_attr), GFP_KERNEL);
-		if (dattr) {
-			*dattr = SD_ATTR_INIT;
-			update_domain_attr_tree(dattr, &top_cpuset);
-		}
-		cpumask_and(doms[0], top_cpuset.effective_cpus,
-				     non_isolated_cpus);
-
-		goto done;
-	}
-
-	csa = kmalloc(nr_cpusets() * sizeof(cp), GFP_KERNEL);
-	if (!csa)
-		goto done;
-	csn = 0;
-
-	rcu_read_lock();
-	cpuset_for_each_descendant_pre(cp, pos_css, &top_cpuset) {
-		if (cp == &top_cpuset)
-			continue;
-		/*
-		 * Continue traversing beyond @cp iff @cp has some CPUs and
-		 * isn't load balancing.  The former is obvious.  The
-		 * latter: All child cpusets contain a subset of the
-		 * parent's cpus, so just skip them, and then we call
-		 * update_domain_attr_tree() to calc relax_domain_level of
-		 * the corresponding sched domain.
-		 */
-		if (!cpumask_empty(cp->cpus_allowed) &&
-		    !(is_sched_load_balance(cp) &&
-		      cpumask_intersects(cp->cpus_allowed, non_isolated_cpus)))
-			continue;
-
-		if (is_sched_load_balance(cp))
-			csa[csn++] = cp;
-
-		/* skip @cp's subtree */
-		pos_css = css_rightmost_descendant(pos_css);
-	}
-	rcu_read_unlock();
-
-	for (i = 0; i < csn; i++)
-		csa[i]->pn = i;
-	ndoms = csn;
-
-restart:
-	/* Find the best partition (set of sched domains) */
-	for (i = 0; i < csn; i++) {
-		struct cpuset *a = csa[i];
-		int apn = a->pn;
-
-		for (j = 0; j < csn; j++) {
-			struct cpuset *b = csa[j];
-			int bpn = b->pn;
-
-			if (apn != bpn && cpusets_overlap(a, b)) {
-				for (k = 0; k < csn; k++) {
-					struct cpuset *c = csa[k];
-
-					if (c->pn == bpn)
-						c->pn = apn;
-				}
-				ndoms--;	/* one less element */
-				goto restart;
-			}
-		}
-	}
-
-	/*
-	 * Now we know how many domains to create.
-	 * Convert <csn, csa> to <ndoms, doms> and populate cpu masks.
-	 */
-	doms = alloc_sched_domains(ndoms);
-	if (!doms)
-		goto done;
-
-	/*
-	 * The rest of the code, including the scheduler, can deal with
-	 * dattr==NULL case. No need to abort if alloc fails.
-	 */
-	dattr = kmalloc(ndoms * sizeof(struct sched_domain_attr), GFP_KERNEL);
-
-	for (nslot = 0, i = 0; i < csn; i++) {
-		struct cpuset *a = csa[i];
-		struct cpumask *dp;
-		int apn = a->pn;
-
-		if (apn < 0) {
-			/* Skip completed partitions */
-			continue;
-		}
-
-		dp = doms[nslot];
-
-		if (nslot == ndoms) {
-			static int warnings = 10;
-			if (warnings) {
-				pr_warn("rebuild_sched_domains confused: nslot %d, ndoms %d, csn %d, i %d, apn %d\n",
-					nslot, ndoms, csn, i, apn);
-				warnings--;
-			}
-			continue;
-		}
-
-		cpumask_clear(dp);
-		if (dattr)
-			*(dattr + nslot) = SD_ATTR_INIT;
-		for (j = i; j < csn; j++) {
-			struct cpuset *b = csa[j];
-
-			if (apn == b->pn) {
-				cpumask_or(dp, dp, b->effective_cpus);
-				cpumask_and(dp, dp, non_isolated_cpus);
-				if (dattr)
-					update_domain_attr_tree(dattr + nslot, b);
-
-				/* Done with this partition */
-				b->pn = -1;
-			}
-		}
-		nslot++;
-	}
-	BUG_ON(nslot != ndoms);
-
-done:
-	free_cpumask_var(non_isolated_cpus);
-	kfree(csa);
-
-	/*
-	 * Fallback to the default domain if kmalloc() failed.
-	 * See comments in partition_sched_domains().
-	 */
-	if (doms == NULL)
-		ndoms = 1;
-
-	*domains    = doms;
-	*attributes = dattr;
-	return ndoms;
-}
-
-/*
- * Rebuild scheduler domains.
- *
- * If the flag 'sched_load_balance' of any cpuset with non-empty
- * 'cpus' changes, or if the 'cpus' allowed changes in any cpuset
- * which has that flag enabled, or if any cpuset with a non-empty
- * 'cpus' is removed, then call this routine to rebuild the
- * scheduler's dynamic sched domains.
- *
- * Call with cpuset_mutex held.  Takes get_online_cpus().
- */
-static void rebuild_sched_domains_locked(void)
-{
-	struct sched_domain_attr *attr;
-	cpumask_var_t *doms;
-	int ndoms;
-
-	lockdep_assert_held(&cpuset_mutex);
-	get_online_cpus();
-
-	/*
-	 * We have raced with CPU hotplug. Don't do anything to avoid
-	 * passing doms with offlined cpu to partition_sched_domains().
-	 * Anyways, hotplug work item will rebuild sched domains.
-	 */
-	if (!cpumask_equal(top_cpuset.effective_cpus, cpu_active_mask))
-		goto out;
-
-	/* Generate domain masks and attrs */
-	ndoms = generate_sched_domains(&doms, &attr);
-
-	/* Have scheduler rebuild the domains */
-	partition_sched_domains(ndoms, doms, attr);
-out:
-	put_online_cpus();
-}
-#else /* !CONFIG_SMP */
-static void rebuild_sched_domains_locked(void)
-{
-}
-#endif /* CONFIG_SMP */
-
-void rebuild_sched_domains(void)
-{
-	mutex_lock(&cpuset_mutex);
-	rebuild_sched_domains_locked();
-	mutex_unlock(&cpuset_mutex);
-}
-
-/**
- * update_tasks_cpumask - Update the cpumasks of tasks in the cpuset.
- * @cs: the cpuset in which each task's cpus_allowed mask needs to be changed
- *
- * Iterate through each task of @cs updating its cpus_allowed to the
- * effective cpuset's.  As this function is called with cpuset_mutex held,
- * cpuset membership stays stable.
- */
-static void update_tasks_cpumask(struct cpuset *cs)
-{
-	struct css_task_iter it;
-	struct task_struct *task;
-
-	css_task_iter_start(&cs->css, &it);
-	while ((task = css_task_iter_next(&it)))
-		set_cpus_allowed_ptr(task, cs->effective_cpus);
-	css_task_iter_end(&it);
-}
-
-/*
- * update_cpumasks_hier - Update effective cpumasks and tasks in the subtree
- * @cs: the cpuset to consider
- * @new_cpus: temp variable for calculating new effective_cpus
- *
- * When congifured cpumask is changed, the effective cpumasks of this cpuset
- * and all its descendants need to be updated.
- *
- * On legacy hierachy, effective_cpus will be the same with cpu_allowed.
- *
- * Called with cpuset_mutex held
- */
-static void update_cpumasks_hier(struct cpuset *cs, struct cpumask *new_cpus)
-{
-	struct cpuset *cp;
-	struct cgroup_subsys_state *pos_css;
-	bool need_rebuild_sched_domains = false;
-
-	rcu_read_lock();
-	cpuset_for_each_descendant_pre(cp, pos_css, cs) {
-		struct cpuset *parent = parent_cs(cp);
-
-		cpumask_and(new_cpus, cp->cpus_allowed, parent->effective_cpus);
-
-		/*
-		 * If it becomes empty, inherit the effective mask of the
-		 * parent, which is guaranteed to have some CPUs.
-		 */
-		if (cgroup_subsys_on_dfl(cpuset_cgrp_subsys) &&
-		    cpumask_empty(new_cpus))
-			cpumask_copy(new_cpus, parent->effective_cpus);
-
-		/* Skip the whole subtree if the cpumask remains the same. */
-		if (cpumask_equal(new_cpus, cp->effective_cpus)) {
-			pos_css = css_rightmost_descendant(pos_css);
-			continue;
-		}
-
-		if (!css_tryget_online(&cp->css))
-			continue;
-		rcu_read_unlock();
-
-		spin_lock_irq(&callback_lock);
-		cpumask_copy(cp->effective_cpus, new_cpus);
-		spin_unlock_irq(&callback_lock);
-
-		WARN_ON(!cgroup_subsys_on_dfl(cpuset_cgrp_subsys) &&
-			!cpumask_equal(cp->cpus_allowed, cp->effective_cpus));
-
-		update_tasks_cpumask(cp);
-
-		/*
-		 * If the effective cpumask of any non-empty cpuset is changed,
-		 * we need to rebuild sched domains.
-		 */
-		if (!cpumask_empty(cp->cpus_allowed) &&
-		    is_sched_load_balance(cp))
-			need_rebuild_sched_domains = true;
-
-		rcu_read_lock();
-		css_put(&cp->css);
-	}
-	rcu_read_unlock();
-
-	if (need_rebuild_sched_domains)
-		rebuild_sched_domains_locked();
-}
-
-/**
- * update_cpumask - update the cpus_allowed mask of a cpuset and all tasks in it
- * @cs: the cpuset to consider
- * @trialcs: trial cpuset
- * @buf: buffer of cpu numbers written to this cpuset
- */
-static int update_cpumask(struct cpuset *cs, struct cpuset *trialcs,
-			  const char *buf)
-{
-	int retval;
-
-	/* top_cpuset.cpus_allowed tracks cpu_online_mask; it's read-only */
-	if (cs == &top_cpuset)
-		return -EACCES;
-
-	/*
-	 * An empty cpus_allowed is ok only if the cpuset has no tasks.
-	 * Since cpulist_parse() fails on an empty mask, we special case
-	 * that parsing.  The validate_change() call ensures that cpusets
-	 * with tasks have cpus.
-	 */
-	if (!*buf) {
-		cpumask_clear(trialcs->cpus_allowed);
-	} else {
-		retval = cpulist_parse(buf, trialcs->cpus_allowed);
-		if (retval < 0)
-			return retval;
-
-		if (!cpumask_subset(trialcs->cpus_allowed,
-				    top_cpuset.cpus_allowed))
-			return -EINVAL;
-	}
-
-	/* Nothing to do if the cpus didn't change */
-	if (cpumask_equal(cs->cpus_allowed, trialcs->cpus_allowed))
-		return 0;
-
-	retval = validate_change(cs, trialcs);
-	if (retval < 0)
-		return retval;
-
-	spin_lock_irq(&callback_lock);
-	cpumask_copy(cs->cpus_allowed, trialcs->cpus_allowed);
-	spin_unlock_irq(&callback_lock);
-
-	/* use trialcs->cpus_allowed as a temp variable */
-	update_cpumasks_hier(cs, trialcs->cpus_allowed);
-	return 0;
-}
-
-/*
- * Migrate memory region from one set of nodes to another.  This is
- * performed asynchronously as it can be called from process migration path
- * holding locks involved in process management.  All mm migrations are
- * performed in the queued order and can be waited for by flushing
- * cpuset_migrate_mm_wq.
- */
-
-struct cpuset_migrate_mm_work {
-	struct work_struct	work;
-	struct mm_struct	*mm;
-	nodemask_t		from;
-	nodemask_t		to;
-};
-
-static void cpuset_migrate_mm_workfn(struct work_struct *work)
-{
-	struct cpuset_migrate_mm_work *mwork =
-		container_of(work, struct cpuset_migrate_mm_work, work);
-
-	/* on a wq worker, no need to worry about %current's mems_allowed */
-	do_migrate_pages(mwork->mm, &mwork->from, &mwork->to, MPOL_MF_MOVE_ALL);
-	mmput(mwork->mm);
-	kfree(mwork);
-}
-
-static void cpuset_migrate_mm(struct mm_struct *mm, const nodemask_t *from,
-							const nodemask_t *to)
-{
-	struct cpuset_migrate_mm_work *mwork;
-
-	mwork = kzalloc(sizeof(*mwork), GFP_KERNEL);
-	if (mwork) {
-		mwork->mm = mm;
-		mwork->from = *from;
-		mwork->to = *to;
-		INIT_WORK(&mwork->work, cpuset_migrate_mm_workfn);
-		queue_work(cpuset_migrate_mm_wq, &mwork->work);
-	} else {
-		mmput(mm);
-	}
-}
-
-static void cpuset_post_attach(void)
-{
-	flush_workqueue(cpuset_migrate_mm_wq);
-}
-
-/*
- * cpuset_change_task_nodemask - change task's mems_allowed and mempolicy
- * @tsk: the task to change
- * @newmems: new nodes that the task will be set
- *
- * In order to avoid seeing no nodes if the old and new nodes are disjoint,
- * we structure updates as setting all new allowed nodes, then clearing newly
- * disallowed ones.
- */
-static void cpuset_change_task_nodemask(struct task_struct *tsk,
-					nodemask_t *newmems)
-{
-	bool need_loop;
-
-	task_lock(tsk);
-	/*
-	 * Determine if a loop is necessary if another thread is doing
-	 * read_mems_allowed_begin().  If at least one node remains unchanged and
-	 * tsk does not have a mempolicy, then an empty nodemask will not be
-	 * possible when mems_allowed is larger than a word.
-	 */
-	need_loop = task_has_mempolicy(tsk) ||
-			!nodes_intersects(*newmems, tsk->mems_allowed);
-
-	if (need_loop) {
-		local_irq_disable();
-		write_seqcount_begin(&tsk->mems_allowed_seq);
-	}
-
-	nodes_or(tsk->mems_allowed, tsk->mems_allowed, *newmems);
-	mpol_rebind_task(tsk, newmems, MPOL_REBIND_STEP1);
-
-	mpol_rebind_task(tsk, newmems, MPOL_REBIND_STEP2);
-	tsk->mems_allowed = *newmems;
-
-	if (need_loop) {
-		write_seqcount_end(&tsk->mems_allowed_seq);
-		local_irq_enable();
-	}
-
-	task_unlock(tsk);
-}
-
-static void *cpuset_being_rebound;
-
-/**
- * update_tasks_nodemask - Update the nodemasks of tasks in the cpuset.
- * @cs: the cpuset in which each task's mems_allowed mask needs to be changed
- *
- * Iterate through each task of @cs updating its mems_allowed to the
- * effective cpuset's.  As this function is called with cpuset_mutex held,
- * cpuset membership stays stable.
- */
-static void update_tasks_nodemask(struct cpuset *cs)
-{
-	static nodemask_t newmems;	/* protected by cpuset_mutex */
-	struct css_task_iter it;
-	struct task_struct *task;
-
-	cpuset_being_rebound = cs;		/* causes mpol_dup() rebind */
-
-	guarantee_online_mems(cs, &newmems);
-
-	/*
-	 * The mpol_rebind_mm() call takes mmap_sem, which we couldn't
-	 * take while holding tasklist_lock.  Forks can happen - the
-	 * mpol_dup() cpuset_being_rebound check will catch such forks,
-	 * and rebind their vma mempolicies too.  Because we still hold
-	 * the global cpuset_mutex, we know that no other rebind effort
-	 * will be contending for the global variable cpuset_being_rebound.
-	 * It's ok if we rebind the same mm twice; mpol_rebind_mm()
-	 * is idempotent.  Also migrate pages in each mm to new nodes.
-	 */
-	css_task_iter_start(&cs->css, &it);
-	while ((task = css_task_iter_next(&it))) {
-		struct mm_struct *mm;
-		bool migrate;
-
-		cpuset_change_task_nodemask(task, &newmems);
-
-		mm = get_task_mm(task);
-		if (!mm)
-			continue;
-
-		migrate = is_memory_migrate(cs);
-
-		mpol_rebind_mm(mm, &cs->mems_allowed);
-		if (migrate)
-			cpuset_migrate_mm(mm, &cs->old_mems_allowed, &newmems);
-		else
-			mmput(mm);
-	}
-	css_task_iter_end(&it);
-
-	/*
-	 * All the tasks' nodemasks have been updated, update
-	 * cs->old_mems_allowed.
-	 */
-	cs->old_mems_allowed = newmems;
-
-	/* We're done rebinding vmas to this cpuset's new mems_allowed. */
-	cpuset_being_rebound = NULL;
-}
-
-/*
- * update_nodemasks_hier - Update effective nodemasks and tasks in the subtree
- * @cs: the cpuset to consider
- * @new_mems: a temp variable for calculating new effective_mems
- *
- * When configured nodemask is changed, the effective nodemasks of this cpuset
- * and all its descendants need to be updated.
- *
- * On legacy hiearchy, effective_mems will be the same with mems_allowed.
- *
- * Called with cpuset_mutex held
- */
-static void update_nodemasks_hier(struct cpuset *cs, nodemask_t *new_mems)
-{
-	struct cpuset *cp;
-	struct cgroup_subsys_state *pos_css;
-
-	rcu_read_lock();
-	cpuset_for_each_descendant_pre(cp, pos_css, cs) {
-		struct cpuset *parent = parent_cs(cp);
-
-		nodes_and(*new_mems, cp->mems_allowed, parent->effective_mems);
-
-		/*
-		 * If it becomes empty, inherit the effective mask of the
-		 * parent, which is guaranteed to have some MEMs.
-		 */
-		if (cgroup_subsys_on_dfl(cpuset_cgrp_subsys) &&
-		    nodes_empty(*new_mems))
-			*new_mems = parent->effective_mems;
-
-		/* Skip the whole subtree if the nodemask remains the same. */
-		if (nodes_equal(*new_mems, cp->effective_mems)) {
-			pos_css = css_rightmost_descendant(pos_css);
-			continue;
-		}
-
-		if (!css_tryget_online(&cp->css))
-			continue;
-		rcu_read_unlock();
-
-		spin_lock_irq(&callback_lock);
-		cp->effective_mems = *new_mems;
-		spin_unlock_irq(&callback_lock);
-
-		WARN_ON(!cgroup_subsys_on_dfl(cpuset_cgrp_subsys) &&
-			!nodes_equal(cp->mems_allowed, cp->effective_mems));
-
-		update_tasks_nodemask(cp);
-
-		rcu_read_lock();
-		css_put(&cp->css);
-	}
-	rcu_read_unlock();
-}
-
-/*
- * Handle user request to change the 'mems' memory placement
- * of a cpuset.  Needs to validate the request, update the
- * cpusets mems_allowed, and for each task in the cpuset,
- * update mems_allowed and rebind task's mempolicy and any vma
- * mempolicies and if the cpuset is marked 'memory_migrate',
- * migrate the tasks pages to the new memory.
- *
- * Call with cpuset_mutex held. May take callback_lock during call.
- * Will take tasklist_lock, scan tasklist for tasks in cpuset cs,
- * lock each such tasks mm->mmap_sem, scan its vma's and rebind
- * their mempolicies to the cpusets new mems_allowed.
- */
-static int update_nodemask(struct cpuset *cs, struct cpuset *trialcs,
-			   const char *buf)
-{
-	int retval;
-
-	/*
-	 * top_cpuset.mems_allowed tracks node_stats[N_MEMORY];
-	 * it's read-only
-	 */
-	if (cs == &top_cpuset) {
-		retval = -EACCES;
-		goto done;
-	}
-
-	/*
-	 * An empty mems_allowed is ok iff there are no tasks in the cpuset.
-	 * Since nodelist_parse() fails on an empty mask, we special case
-	 * that parsing.  The validate_change() call ensures that cpusets
-	 * with tasks have memory.
-	 */
-	if (!*buf) {
-		nodes_clear(trialcs->mems_allowed);
-	} else {
-		retval = nodelist_parse(buf, trialcs->mems_allowed);
-		if (retval < 0)
-			goto done;
-
-		if (!nodes_subset(trialcs->mems_allowed,
-				  top_cpuset.mems_allowed)) {
-			retval = -EINVAL;
-			goto done;
-		}
-	}
-
-	if (nodes_equal(cs->mems_allowed, trialcs->mems_allowed)) {
-		retval = 0;		/* Too easy - nothing to do */
-		goto done;
-	}
-	retval = validate_change(cs, trialcs);
-	if (retval < 0)
-		goto done;
-
-	spin_lock_irq(&callback_lock);
-	cs->mems_allowed = trialcs->mems_allowed;
-	spin_unlock_irq(&callback_lock);
-
-	/* use trialcs->mems_allowed as a temp variable */
-	update_nodemasks_hier(cs, &trialcs->mems_allowed);
-done:
-	return retval;
-}
-
-int current_cpuset_is_being_rebound(void)
-{
-	int ret;
-
-	rcu_read_lock();
-	ret = task_cs(current) == cpuset_being_rebound;
-	rcu_read_unlock();
-
-	return ret;
-}
-
-static int update_relax_domain_level(struct cpuset *cs, s64 val)
-{
-#ifdef CONFIG_SMP
-	if (val < -1 || val >= sched_domain_level_max)
-		return -EINVAL;
-#endif
-
-	if (val != cs->relax_domain_level) {
-		cs->relax_domain_level = val;
-		if (!cpumask_empty(cs->cpus_allowed) &&
-		    is_sched_load_balance(cs))
-			rebuild_sched_domains_locked();
-	}
-
-	return 0;
-}
-
-/**
- * update_tasks_flags - update the spread flags of tasks in the cpuset.
- * @cs: the cpuset in which each task's spread flags needs to be changed
- *
- * Iterate through each task of @cs updating its spread flags.  As this
- * function is called with cpuset_mutex held, cpuset membership stays
- * stable.
- */
-static void update_tasks_flags(struct cpuset *cs)
-{
-	struct css_task_iter it;
-	struct task_struct *task;
-
-	css_task_iter_start(&cs->css, &it);
-	while ((task = css_task_iter_next(&it)))
-		cpuset_update_task_spread_flag(cs, task);
-	css_task_iter_end(&it);
-}
-
-/*
- * update_flag - read a 0 or a 1 in a file and update associated flag
- * bit:		the bit to update (see cpuset_flagbits_t)
- * cs:		the cpuset to update
- * turning_on: 	whether the flag is being set or cleared
- *
- * Call with cpuset_mutex held.
- */
-
-static int update_flag(cpuset_flagbits_t bit, struct cpuset *cs,
-		       int turning_on)
-{
-	struct cpuset *trialcs;
-	int balance_flag_changed;
-	int spread_flag_changed;
-	int err;
-
-	trialcs = alloc_trial_cpuset(cs);
-	if (!trialcs)
-		return -ENOMEM;
-
-	if (turning_on)
-		set_bit(bit, &trialcs->flags);
-	else
-		clear_bit(bit, &trialcs->flags);
-
-	err = validate_change(cs, trialcs);
-	if (err < 0)
-		goto out;
-
-	balance_flag_changed = (is_sched_load_balance(cs) !=
-				is_sched_load_balance(trialcs));
-
-	spread_flag_changed = ((is_spread_slab(cs) != is_spread_slab(trialcs))
-			|| (is_spread_page(cs) != is_spread_page(trialcs)));
-
-	spin_lock_irq(&callback_lock);
-	cs->flags = trialcs->flags;
-	spin_unlock_irq(&callback_lock);
-
-	if (!cpumask_empty(trialcs->cpus_allowed) && balance_flag_changed)
-		rebuild_sched_domains_locked();
-
-	if (spread_flag_changed)
-		update_tasks_flags(cs);
-out:
-	free_trial_cpuset(trialcs);
-	return err;
-}
-
-/*
- * Frequency meter - How fast is some event occurring?
- *
- * These routines manage a digitally filtered, constant time based,
- * event frequency meter.  There are four routines:
- *   fmeter_init() - initialize a frequency meter.
- *   fmeter_markevent() - called each time the event happens.
- *   fmeter_getrate() - returns the recent rate of such events.
- *   fmeter_update() - internal routine used to update fmeter.
- *
- * A common data structure is passed to each of these routines,
- * which is used to keep track of the state required to manage the
- * frequency meter and its digital filter.
- *
- * The filter works on the number of events marked per unit time.
- * The filter is single-pole low-pass recursive (IIR).  The time unit
- * is 1 second.  Arithmetic is done using 32-bit integers scaled to
- * simulate 3 decimal digits of precision (multiplied by 1000).
- *
- * With an FM_COEF of 933, and a time base of 1 second, the filter
- * has a half-life of 10 seconds, meaning that if the events quit
- * happening, then the rate returned from the fmeter_getrate()
- * will be cut in half each 10 seconds, until it converges to zero.
- *
- * It is not worth doing a real infinitely recursive filter.  If more
- * than FM_MAXTICKS ticks have elapsed since the last filter event,
- * just compute FM_MAXTICKS ticks worth, by which point the level
- * will be stable.
- *
- * Limit the count of unprocessed events to FM_MAXCNT, so as to avoid
- * arithmetic overflow in the fmeter_update() routine.
- *
- * Given the simple 32 bit integer arithmetic used, this meter works
- * best for reporting rates between one per millisecond (msec) and
- * one per 32 (approx) seconds.  At constant rates faster than one
- * per msec it maxes out at values just under 1,000,000.  At constant
- * rates between one per msec, and one per second it will stabilize
- * to a value N*1000, where N is the rate of events per second.
- * At constant rates between one per second and one per 32 seconds,
- * it will be choppy, moving up on the seconds that have an event,
- * and then decaying until the next event.  At rates slower than
- * about one in 32 seconds, it decays all the way back to zero between
- * each event.
- */
-
-#define FM_COEF 933		/* coefficient for half-life of 10 secs */
-#define FM_MAXTICKS ((u32)99)   /* useless computing more ticks than this */
-#define FM_MAXCNT 1000000	/* limit cnt to avoid overflow */
-#define FM_SCALE 1000		/* faux fixed point scale */
-
-/* Initialize a frequency meter */
-static void fmeter_init(struct fmeter *fmp)
-{
-	fmp->cnt = 0;
-	fmp->val = 0;
-	fmp->time = 0;
-	spin_lock_init(&fmp->lock);
-}
-
-/* Internal meter update - process cnt events and update value */
-static void fmeter_update(struct fmeter *fmp)
-{
-	time64_t now;
-	u32 ticks;
-
-	now = ktime_get_seconds();
-	ticks = now - fmp->time;
-
-	if (ticks == 0)
-		return;
-
-	ticks = min(FM_MAXTICKS, ticks);
-	while (ticks-- > 0)
-		fmp->val = (FM_COEF * fmp->val) / FM_SCALE;
-	fmp->time = now;
-
-	fmp->val += ((FM_SCALE - FM_COEF) * fmp->cnt) / FM_SCALE;
-	fmp->cnt = 0;
-}
-
-/* Process any previous ticks, then bump cnt by one (times scale). */
-static void fmeter_markevent(struct fmeter *fmp)
-{
-	spin_lock(&fmp->lock);
-	fmeter_update(fmp);
-	fmp->cnt = min(FM_MAXCNT, fmp->cnt + FM_SCALE);
-	spin_unlock(&fmp->lock);
-}
-
-/* Process any previous ticks, then return current value. */
-static int fmeter_getrate(struct fmeter *fmp)
-{
-	int val;
-
-	spin_lock(&fmp->lock);
-	fmeter_update(fmp);
-	val = fmp->val;
-	spin_unlock(&fmp->lock);
-	return val;
-}
-
-static struct cpuset *cpuset_attach_old_cs;
-
-/* Called by cgroups to determine if a cpuset is usable; cpuset_mutex held */
-static int cpuset_can_attach(struct cgroup_taskset *tset)
-{
-	struct cgroup_subsys_state *css;
-	struct cpuset *cs;
-	struct task_struct *task;
-	int ret;
-
-	/* used later by cpuset_attach() */
-	cpuset_attach_old_cs = task_cs(cgroup_taskset_first(tset, &css));
-	cs = css_cs(css);
-
-	mutex_lock(&cpuset_mutex);
-
-	/* allow moving tasks into an empty cpuset if on default hierarchy */
-	ret = -ENOSPC;
-	if (!cgroup_subsys_on_dfl(cpuset_cgrp_subsys) &&
-	    (cpumask_empty(cs->cpus_allowed) || nodes_empty(cs->mems_allowed)))
-		goto out_unlock;
-
-	cgroup_taskset_for_each(task, css, tset) {
-		ret = task_can_attach(task, cs->cpus_allowed);
-		if (ret)
-			goto out_unlock;
-		ret = security_task_setscheduler(task);
-		if (ret)
-			goto out_unlock;
-	}
-
-	/*
-	 * Mark attach is in progress.  This makes validate_change() fail
-	 * changes which zero cpus/mems_allowed.
-	 */
-	cs->attach_in_progress++;
-	ret = 0;
-out_unlock:
-	mutex_unlock(&cpuset_mutex);
-	return ret;
-}
-
-static void cpuset_cancel_attach(struct cgroup_taskset *tset)
-{
-	struct cgroup_subsys_state *css;
-	struct cpuset *cs;
-
-	cgroup_taskset_first(tset, &css);
-	cs = css_cs(css);
-
-	mutex_lock(&cpuset_mutex);
-	css_cs(css)->attach_in_progress--;
-	mutex_unlock(&cpuset_mutex);
-}
-
-/*
- * Protected by cpuset_mutex.  cpus_attach is used only by cpuset_attach()
- * but we can't allocate it dynamically there.  Define it global and
- * allocate from cpuset_init().
- */
-static cpumask_var_t cpus_attach;
-
-static void cpuset_attach(struct cgroup_taskset *tset)
-{
-	/* static buf protected by cpuset_mutex */
-	static nodemask_t cpuset_attach_nodemask_to;
-	struct task_struct *task;
-	struct task_struct *leader;
-	struct cgroup_subsys_state *css;
-	struct cpuset *cs;
-	struct cpuset *oldcs = cpuset_attach_old_cs;
-
-	cgroup_taskset_first(tset, &css);
-	cs = css_cs(css);
-
-	mutex_lock(&cpuset_mutex);
-
-	/* prepare for attach */
-	if (cs == &top_cpuset)
-		cpumask_copy(cpus_attach, cpu_possible_mask);
-	else
-		guarantee_online_cpus(cs, cpus_attach);
-
-	guarantee_online_mems(cs, &cpuset_attach_nodemask_to);
-
-	cgroup_taskset_for_each(task, css, tset) {
-		/*
-		 * can_attach beforehand should guarantee that this doesn't
-		 * fail.  TODO: have a better way to handle failure here
-		 */
-		WARN_ON_ONCE(set_cpus_allowed_ptr(task, cpus_attach));
-
-		cpuset_change_task_nodemask(task, &cpuset_attach_nodemask_to);
-		cpuset_update_task_spread_flag(cs, task);
-	}
-
-	/*
-	 * Change mm for all threadgroup leaders. This is expensive and may
-	 * sleep and should be moved outside migration path proper.
-	 */
-	cpuset_attach_nodemask_to = cs->effective_mems;
-	cgroup_taskset_for_each_leader(leader, css, tset) {
-		struct mm_struct *mm = get_task_mm(leader);
-
-		if (mm) {
-			mpol_rebind_mm(mm, &cpuset_attach_nodemask_to);
-
-			/*
-			 * old_mems_allowed is the same with mems_allowed
-			 * here, except if this task is being moved
-			 * automatically due to hotplug.  In that case
-			 * @mems_allowed has been updated and is empty, so
-			 * @old_mems_allowed is the right nodesets that we
-			 * migrate mm from.
-			 */
-			if (is_memory_migrate(cs))
-				cpuset_migrate_mm(mm, &oldcs->old_mems_allowed,
-						  &cpuset_attach_nodemask_to);
-			else
-				mmput(mm);
-		}
-	}
-
-	cs->old_mems_allowed = cpuset_attach_nodemask_to;
-
-	cs->attach_in_progress--;
-	if (!cs->attach_in_progress)
-		wake_up(&cpuset_attach_wq);
-
-	mutex_unlock(&cpuset_mutex);
-}
-
-/* The various types of files and directories in a cpuset file system */
-
-typedef enum {
-	FILE_MEMORY_MIGRATE,
-	FILE_CPULIST,
-	FILE_MEMLIST,
-	FILE_EFFECTIVE_CPULIST,
-	FILE_EFFECTIVE_MEMLIST,
-	FILE_CPU_EXCLUSIVE,
-	FILE_MEM_EXCLUSIVE,
-	FILE_MEM_HARDWALL,
-	FILE_SCHED_LOAD_BALANCE,
-	FILE_SCHED_RELAX_DOMAIN_LEVEL,
-	FILE_MEMORY_PRESSURE_ENABLED,
-	FILE_MEMORY_PRESSURE,
-	FILE_SPREAD_PAGE,
-	FILE_SPREAD_SLAB,
-} cpuset_filetype_t;
-
-static int cpuset_write_u64(struct cgroup_subsys_state *css, struct cftype *cft,
-			    u64 val)
-{
-	struct cpuset *cs = css_cs(css);
-	cpuset_filetype_t type = cft->private;
-	int retval = 0;
-
-	mutex_lock(&cpuset_mutex);
-	if (!is_cpuset_online(cs)) {
-		retval = -ENODEV;
-		goto out_unlock;
-	}
-
-	switch (type) {
-	case FILE_CPU_EXCLUSIVE:
-		retval = update_flag(CS_CPU_EXCLUSIVE, cs, val);
-		break;
-	case FILE_MEM_EXCLUSIVE:
-		retval = update_flag(CS_MEM_EXCLUSIVE, cs, val);
-		break;
-	case FILE_MEM_HARDWALL:
-		retval = update_flag(CS_MEM_HARDWALL, cs, val);
-		break;
-	case FILE_SCHED_LOAD_BALANCE:
-		retval = update_flag(CS_SCHED_LOAD_BALANCE, cs, val);
-		break;
-	case FILE_MEMORY_MIGRATE:
-		retval = update_flag(CS_MEMORY_MIGRATE, cs, val);
-		break;
-	case FILE_MEMORY_PRESSURE_ENABLED:
-		cpuset_memory_pressure_enabled = !!val;
-		break;
-	case FILE_SPREAD_PAGE:
-		retval = update_flag(CS_SPREAD_PAGE, cs, val);
-		break;
-	case FILE_SPREAD_SLAB:
-		retval = update_flag(CS_SPREAD_SLAB, cs, val);
-		break;
-	default:
-		retval = -EINVAL;
-		break;
-	}
-out_unlock:
-	mutex_unlock(&cpuset_mutex);
-	return retval;
-}
-
-static int cpuset_write_s64(struct cgroup_subsys_state *css, struct cftype *cft,
-			    s64 val)
-{
-	struct cpuset *cs = css_cs(css);
-	cpuset_filetype_t type = cft->private;
-	int retval = -ENODEV;
-
-	mutex_lock(&cpuset_mutex);
-	if (!is_cpuset_online(cs))
-		goto out_unlock;
-
-	switch (type) {
-	case FILE_SCHED_RELAX_DOMAIN_LEVEL:
-		retval = update_relax_domain_level(cs, val);
-		break;
-	default:
-		retval = -EINVAL;
-		break;
-	}
-out_unlock:
-	mutex_unlock(&cpuset_mutex);
-	return retval;
-}
-
-/*
- * Common handling for a write to a "cpus" or "mems" file.
- */
-static ssize_t cpuset_write_resmask(struct kernfs_open_file *of,
-				    char *buf, size_t nbytes, loff_t off)
-{
-	struct cpuset *cs = css_cs(of_css(of));
-	struct cpuset *trialcs;
-	int retval = -ENODEV;
-
-	buf = strstrip(buf);
-
-	/*
-	 * CPU or memory hotunplug may leave @cs w/o any execution
-	 * resources, in which case the hotplug code asynchronously updates
-	 * configuration and transfers all tasks to the nearest ancestor
-	 * which can execute.
-	 *
-	 * As writes to "cpus" or "mems" may restore @cs's execution
-	 * resources, wait for the previously scheduled operations before
-	 * proceeding, so that we don't end up keep removing tasks added
-	 * after execution capability is restored.
-	 *
-	 * cpuset_hotplug_work calls back into cgroup core via
-	 * cgroup_transfer_tasks() and waiting for it from a cgroupfs
-	 * operation like this one can lead to a deadlock through kernfs
-	 * active_ref protection.  Let's break the protection.  Losing the
-	 * protection is okay as we check whether @cs is online after
-	 * grabbing cpuset_mutex anyway.  This only happens on the legacy
-	 * hierarchies.
-	 */
-	css_get(&cs->css);
-	kernfs_break_active_protection(of->kn);
-	flush_work(&cpuset_hotplug_work);
-
-	mutex_lock(&cpuset_mutex);
-	if (!is_cpuset_online(cs))
-		goto out_unlock;
-
-	trialcs = alloc_trial_cpuset(cs);
-	if (!trialcs) {
-		retval = -ENOMEM;
-		goto out_unlock;
-	}
-
-	switch (of_cft(of)->private) {
-	case FILE_CPULIST:
-		retval = update_cpumask(cs, trialcs, buf);
-		break;
-	case FILE_MEMLIST:
-		retval = update_nodemask(cs, trialcs, buf);
-		break;
-	default:
-		retval = -EINVAL;
-		break;
-	}
-
-	free_trial_cpuset(trialcs);
-out_unlock:
-	mutex_unlock(&cpuset_mutex);
-	kernfs_unbreak_active_protection(of->kn);
-	css_put(&cs->css);
-	flush_workqueue(cpuset_migrate_mm_wq);
-	return retval ?: nbytes;
-}
-
-/*
- * These ascii lists should be read in a single call, by using a user
- * buffer large enough to hold the entire map.  If read in smaller
- * chunks, there is no guarantee of atomicity.  Since the display format
- * used, list of ranges of sequential numbers, is variable length,
- * and since these maps can change value dynamically, one could read
- * gibberish by doing partial reads while a list was changing.
- */
-static int cpuset_common_seq_show(struct seq_file *sf, void *v)
-{
-	struct cpuset *cs = css_cs(seq_css(sf));
-	cpuset_filetype_t type = seq_cft(sf)->private;
-	int ret = 0;
-
-	spin_lock_irq(&callback_lock);
-
-	switch (type) {
-	case FILE_CPULIST:
-		seq_printf(sf, "%*pbl\n", cpumask_pr_args(cs->cpus_allowed));
-		break;
-	case FILE_MEMLIST:
-		seq_printf(sf, "%*pbl\n", nodemask_pr_args(&cs->mems_allowed));
-		break;
-	case FILE_EFFECTIVE_CPULIST:
-		seq_printf(sf, "%*pbl\n", cpumask_pr_args(cs->effective_cpus));
-		break;
-	case FILE_EFFECTIVE_MEMLIST:
-		seq_printf(sf, "%*pbl\n", nodemask_pr_args(&cs->effective_mems));
-		break;
-	default:
-		ret = -EINVAL;
-	}
-
-	spin_unlock_irq(&callback_lock);
-	return ret;
-}
-
-static u64 cpuset_read_u64(struct cgroup_subsys_state *css, struct cftype *cft)
-{
-	struct cpuset *cs = css_cs(css);
-	cpuset_filetype_t type = cft->private;
-	switch (type) {
-	case FILE_CPU_EXCLUSIVE:
-		return is_cpu_exclusive(cs);
-	case FILE_MEM_EXCLUSIVE:
-		return is_mem_exclusive(cs);
-	case FILE_MEM_HARDWALL:
-		return is_mem_hardwall(cs);
-	case FILE_SCHED_LOAD_BALANCE:
-		return is_sched_load_balance(cs);
-	case FILE_MEMORY_MIGRATE:
-		return is_memory_migrate(cs);
-	case FILE_MEMORY_PRESSURE_ENABLED:
-		return cpuset_memory_pressure_enabled;
-	case FILE_MEMORY_PRESSURE:
-		return fmeter_getrate(&cs->fmeter);
-	case FILE_SPREAD_PAGE:
-		return is_spread_page(cs);
-	case FILE_SPREAD_SLAB:
-		return is_spread_slab(cs);
-	default:
-		BUG();
-	}
-
-	/* Unreachable but makes gcc happy */
-	return 0;
-}
-
-static s64 cpuset_read_s64(struct cgroup_subsys_state *css, struct cftype *cft)
-{
-	struct cpuset *cs = css_cs(css);
-	cpuset_filetype_t type = cft->private;
-	switch (type) {
-	case FILE_SCHED_RELAX_DOMAIN_LEVEL:
-		return cs->relax_domain_level;
-	default:
-		BUG();
-	}
-
-	/* Unrechable but makes gcc happy */
-	return 0;
-}
-
-
-/*
- * for the common functions, 'private' gives the type of file
- */
-
-static struct cftype files[] = {
-	{
-		.name = "cpus",
-		.seq_show = cpuset_common_seq_show,
-		.write = cpuset_write_resmask,
-		.max_write_len = (100U + 6 * NR_CPUS),
-		.private = FILE_CPULIST,
-	},
-
-	{
-		.name = "mems",
-		.seq_show = cpuset_common_seq_show,
-		.write = cpuset_write_resmask,
-		.max_write_len = (100U + 6 * MAX_NUMNODES),
-		.private = FILE_MEMLIST,
-	},
-
-	{
-		.name = "effective_cpus",
-		.seq_show = cpuset_common_seq_show,
-		.private = FILE_EFFECTIVE_CPULIST,
-	},
-
-	{
-		.name = "effective_mems",
-		.seq_show = cpuset_common_seq_show,
-		.private = FILE_EFFECTIVE_MEMLIST,
-	},
-
-	{
-		.name = "cpu_exclusive",
-		.read_u64 = cpuset_read_u64,
-		.write_u64 = cpuset_write_u64,
-		.private = FILE_CPU_EXCLUSIVE,
-	},
-
-	{
-		.name = "mem_exclusive",
-		.read_u64 = cpuset_read_u64,
-		.write_u64 = cpuset_write_u64,
-		.private = FILE_MEM_EXCLUSIVE,
-	},
-
-	{
-		.name = "mem_hardwall",
-		.read_u64 = cpuset_read_u64,
-		.write_u64 = cpuset_write_u64,
-		.private = FILE_MEM_HARDWALL,
-	},
-
-	{
-		.name = "sched_load_balance",
-		.read_u64 = cpuset_read_u64,
-		.write_u64 = cpuset_write_u64,
-		.private = FILE_SCHED_LOAD_BALANCE,
-	},
-
-	{
-		.name = "sched_relax_domain_level",
-		.read_s64 = cpuset_read_s64,
-		.write_s64 = cpuset_write_s64,
-		.private = FILE_SCHED_RELAX_DOMAIN_LEVEL,
-	},
-
-	{
-		.name = "memory_migrate",
-		.read_u64 = cpuset_read_u64,
-		.write_u64 = cpuset_write_u64,
-		.private = FILE_MEMORY_MIGRATE,
-	},
-
-	{
-		.name = "memory_pressure",
-		.read_u64 = cpuset_read_u64,
-	},
-
-	{
-		.name = "memory_spread_page",
-		.read_u64 = cpuset_read_u64,
-		.write_u64 = cpuset_write_u64,
-		.private = FILE_SPREAD_PAGE,
-	},
-
-	{
-		.name = "memory_spread_slab",
-		.read_u64 = cpuset_read_u64,
-		.write_u64 = cpuset_write_u64,
-		.private = FILE_SPREAD_SLAB,
-	},
-
-	{
-		.name = "memory_pressure_enabled",
-		.flags = CFTYPE_ONLY_ON_ROOT,
-		.read_u64 = cpuset_read_u64,
-		.write_u64 = cpuset_write_u64,
-		.private = FILE_MEMORY_PRESSURE_ENABLED,
-	},
-
-	{ }	/* terminate */
-};
-
-/*
- *	cpuset_css_alloc - allocate a cpuset css
- *	cgrp:	control group that the new cpuset will be part of
- */
-
-static struct cgroup_subsys_state *
-cpuset_css_alloc(struct cgroup_subsys_state *parent_css)
-{
-	struct cpuset *cs;
-
-	if (!parent_css)
-		return &top_cpuset.css;
-
-	cs = kzalloc(sizeof(*cs), GFP_KERNEL);
-	if (!cs)
-		return ERR_PTR(-ENOMEM);
-	if (!alloc_cpumask_var(&cs->cpus_allowed, GFP_KERNEL))
-		goto free_cs;
-	if (!alloc_cpumask_var(&cs->effective_cpus, GFP_KERNEL))
-		goto free_cpus;
-
-	set_bit(CS_SCHED_LOAD_BALANCE, &cs->flags);
-	cpumask_clear(cs->cpus_allowed);
-	nodes_clear(cs->mems_allowed);
-	cpumask_clear(cs->effective_cpus);
-	nodes_clear(cs->effective_mems);
-	fmeter_init(&cs->fmeter);
-	cs->relax_domain_level = -1;
-
-	return &cs->css;
-
-free_cpus:
-	free_cpumask_var(cs->cpus_allowed);
-free_cs:
-	kfree(cs);
-	return ERR_PTR(-ENOMEM);
-}
-
-static int cpuset_css_online(struct cgroup_subsys_state *css)
-{
-	struct cpuset *cs = css_cs(css);
-	struct cpuset *parent = parent_cs(cs);
-	struct cpuset *tmp_cs;
-	struct cgroup_subsys_state *pos_css;
-
-	if (!parent)
-		return 0;
-
-	mutex_lock(&cpuset_mutex);
-
-	set_bit(CS_ONLINE, &cs->flags);
-	if (is_spread_page(parent))
-		set_bit(CS_SPREAD_PAGE, &cs->flags);
-	if (is_spread_slab(parent))
-		set_bit(CS_SPREAD_SLAB, &cs->flags);
-
-	cpuset_inc();
-
-	spin_lock_irq(&callback_lock);
-	if (cgroup_subsys_on_dfl(cpuset_cgrp_subsys)) {
-		cpumask_copy(cs->effective_cpus, parent->effective_cpus);
-		cs->effective_mems = parent->effective_mems;
-	}
-	spin_unlock_irq(&callback_lock);
-
-	if (!test_bit(CGRP_CPUSET_CLONE_CHILDREN, &css->cgroup->flags))
-		goto out_unlock;
-
-	/*
-	 * Clone @parent's configuration if CGRP_CPUSET_CLONE_CHILDREN is
-	 * set.  This flag handling is implemented in cgroup core for
-	 * histrical reasons - the flag may be specified during mount.
-	 *
-	 * Currently, if any sibling cpusets have exclusive cpus or mem, we
-	 * refuse to clone the configuration - thereby refusing the task to
-	 * be entered, and as a result refusing the sys_unshare() or
-	 * clone() which initiated it.  If this becomes a problem for some
-	 * users who wish to allow that scenario, then this could be
-	 * changed to grant parent->cpus_allowed-sibling_cpus_exclusive
-	 * (and likewise for mems) to the new cgroup.
-	 */
-	rcu_read_lock();
-	cpuset_for_each_child(tmp_cs, pos_css, parent) {
-		if (is_mem_exclusive(tmp_cs) || is_cpu_exclusive(tmp_cs)) {
-			rcu_read_unlock();
-			goto out_unlock;
-		}
-	}
-	rcu_read_unlock();
-
-	spin_lock_irq(&callback_lock);
-	cs->mems_allowed = parent->mems_allowed;
-	cs->effective_mems = parent->mems_allowed;
-	cpumask_copy(cs->cpus_allowed, parent->cpus_allowed);
-	cpumask_copy(cs->effective_cpus, parent->cpus_allowed);
-	spin_unlock_irq(&callback_lock);
-out_unlock:
-	mutex_unlock(&cpuset_mutex);
-	return 0;
-}
-
-/*
- * If the cpuset being removed has its flag 'sched_load_balance'
- * enabled, then simulate turning sched_load_balance off, which
- * will call rebuild_sched_domains_locked().
- */
-
-static void cpuset_css_offline(struct cgroup_subsys_state *css)
-{
-	struct cpuset *cs = css_cs(css);
-
-	mutex_lock(&cpuset_mutex);
-
-	if (is_sched_load_balance(cs))
-		update_flag(CS_SCHED_LOAD_BALANCE, cs, 0);
-
-	cpuset_dec();
-	clear_bit(CS_ONLINE, &cs->flags);
-
-	mutex_unlock(&cpuset_mutex);
-}
-
-static void cpuset_css_free(struct cgroup_subsys_state *css)
-{
-	struct cpuset *cs = css_cs(css);
-
-	free_cpumask_var(cs->effective_cpus);
-	free_cpumask_var(cs->cpus_allowed);
-	kfree(cs);
-}
-
-static void cpuset_bind(struct cgroup_subsys_state *root_css)
-{
-	mutex_lock(&cpuset_mutex);
-	spin_lock_irq(&callback_lock);
-
-	if (cgroup_subsys_on_dfl(cpuset_cgrp_subsys)) {
-		cpumask_copy(top_cpuset.cpus_allowed, cpu_possible_mask);
-		top_cpuset.mems_allowed = node_possible_map;
-	} else {
-		cpumask_copy(top_cpuset.cpus_allowed,
-			     top_cpuset.effective_cpus);
-		top_cpuset.mems_allowed = top_cpuset.effective_mems;
-	}
-
-	spin_unlock_irq(&callback_lock);
-	mutex_unlock(&cpuset_mutex);
-}
-
-/*
- * Make sure the new task conform to the current state of its parent,
- * which could have been changed by cpuset just after it inherits the
- * state from the parent and before it sits on the cgroup's task list.
- */
-static void cpuset_fork(struct task_struct *task)
-{
-	if (task_css_is_root(task, cpuset_cgrp_id))
-		return;
-
-	set_cpus_allowed_ptr(task, &current->cpus_allowed);
-	task->mems_allowed = current->mems_allowed;
-}
-
-struct cgroup_subsys cpuset_cgrp_subsys = {
-	.css_alloc	= cpuset_css_alloc,
-	.css_online	= cpuset_css_online,
-	.css_offline	= cpuset_css_offline,
-	.css_free	= cpuset_css_free,
-	.can_attach	= cpuset_can_attach,
-	.cancel_attach	= cpuset_cancel_attach,
-	.attach		= cpuset_attach,
-	.post_attach	= cpuset_post_attach,
-	.bind		= cpuset_bind,
-	.fork		= cpuset_fork,
-	.legacy_cftypes	= files,
-	.early_init	= true,
-};
-
-/**
- * cpuset_init - initialize cpusets at system boot
- *
- * Description: Initialize top_cpuset and the cpuset internal file system,
- **/
-
-int __init cpuset_init(void)
-{
-	int err = 0;
-
-	if (!alloc_cpumask_var(&top_cpuset.cpus_allowed, GFP_KERNEL))
-		BUG();
-	if (!alloc_cpumask_var(&top_cpuset.effective_cpus, GFP_KERNEL))
-		BUG();
-
-	cpumask_setall(top_cpuset.cpus_allowed);
-	nodes_setall(top_cpuset.mems_allowed);
-	cpumask_setall(top_cpuset.effective_cpus);
-	nodes_setall(top_cpuset.effective_mems);
-
-	fmeter_init(&top_cpuset.fmeter);
-	set_bit(CS_SCHED_LOAD_BALANCE, &top_cpuset.flags);
-	top_cpuset.relax_domain_level = -1;
-
-	err = register_filesystem(&cpuset_fs_type);
-	if (err < 0)
-		return err;
-
-	if (!alloc_cpumask_var(&cpus_attach, GFP_KERNEL))
-		BUG();
-
-	return 0;
-}
-
-/*
- * If CPU and/or memory hotplug handlers, below, unplug any CPUs
- * or memory nodes, we need to walk over the cpuset hierarchy,
- * removing that CPU or node from all cpusets.  If this removes the
- * last CPU or node from a cpuset, then move the tasks in the empty
- * cpuset to its next-highest non-empty parent.
- */
-static void remove_tasks_in_empty_cpuset(struct cpuset *cs)
-{
-	struct cpuset *parent;
-
-	/*
-	 * Find its next-highest non-empty parent, (top cpuset
-	 * has online cpus, so can't be empty).
-	 */
-	parent = parent_cs(cs);
-	while (cpumask_empty(parent->cpus_allowed) ||
-			nodes_empty(parent->mems_allowed))
-		parent = parent_cs(parent);
-
-	if (cgroup_transfer_tasks(parent->css.cgroup, cs->css.cgroup)) {
-		pr_err("cpuset: failed to transfer tasks out of empty cpuset ");
-		pr_cont_cgroup_name(cs->css.cgroup);
-		pr_cont("\n");
-	}
-}
-
-static void
-hotplug_update_tasks_legacy(struct cpuset *cs,
-			    struct cpumask *new_cpus, nodemask_t *new_mems,
-			    bool cpus_updated, bool mems_updated)
-{
-	bool is_empty;
-
-	spin_lock_irq(&callback_lock);
-	cpumask_copy(cs->cpus_allowed, new_cpus);
-	cpumask_copy(cs->effective_cpus, new_cpus);
-	cs->mems_allowed = *new_mems;
-	cs->effective_mems = *new_mems;
-	spin_unlock_irq(&callback_lock);
-
-	/*
-	 * Don't call update_tasks_cpumask() if the cpuset becomes empty,
-	 * as the tasks will be migratecd to an ancestor.
-	 */
-	if (cpus_updated && !cpumask_empty(cs->cpus_allowed))
-		update_tasks_cpumask(cs);
-	if (mems_updated && !nodes_empty(cs->mems_allowed))
-		update_tasks_nodemask(cs);
-
-	is_empty = cpumask_empty(cs->cpus_allowed) ||
-		   nodes_empty(cs->mems_allowed);
-
-	mutex_unlock(&cpuset_mutex);
-
-	/*
-	 * Move tasks to the nearest ancestor with execution resources,
-	 * This is full cgroup operation which will also call back into
-	 * cpuset. Should be done outside any lock.
-	 */
-	if (is_empty)
-		remove_tasks_in_empty_cpuset(cs);
-
-	mutex_lock(&cpuset_mutex);
-}
-
-static void
-hotplug_update_tasks(struct cpuset *cs,
-		     struct cpumask *new_cpus, nodemask_t *new_mems,
-		     bool cpus_updated, bool mems_updated)
-{
-	if (cpumask_empty(new_cpus))
-		cpumask_copy(new_cpus, parent_cs(cs)->effective_cpus);
-	if (nodes_empty(*new_mems))
-		*new_mems = parent_cs(cs)->effective_mems;
-
-	spin_lock_irq(&callback_lock);
-	cpumask_copy(cs->effective_cpus, new_cpus);
-	cs->effective_mems = *new_mems;
-	spin_unlock_irq(&callback_lock);
-
-	if (cpus_updated)
-		update_tasks_cpumask(cs);
-	if (mems_updated)
-		update_tasks_nodemask(cs);
-}
-
-/**
- * cpuset_hotplug_update_tasks - update tasks in a cpuset for hotunplug
- * @cs: cpuset in interest
- *
- * Compare @cs's cpu and mem masks against top_cpuset and if some have gone
- * offline, update @cs accordingly.  If @cs ends up with no CPU or memory,
- * all its tasks are moved to the nearest ancestor with both resources.
- */
-static void cpuset_hotplug_update_tasks(struct cpuset *cs)
-{
-	static cpumask_t new_cpus;
-	static nodemask_t new_mems;
-	bool cpus_updated;
-	bool mems_updated;
-retry:
-	wait_event(cpuset_attach_wq, cs->attach_in_progress == 0);
-
-	mutex_lock(&cpuset_mutex);
-
-	/*
-	 * We have raced with task attaching. We wait until attaching
-	 * is finished, so we won't attach a task to an empty cpuset.
-	 */
-	if (cs->attach_in_progress) {
-		mutex_unlock(&cpuset_mutex);
-		goto retry;
-	}
-
-	cpumask_and(&new_cpus, cs->cpus_allowed, parent_cs(cs)->effective_cpus);
-	nodes_and(new_mems, cs->mems_allowed, parent_cs(cs)->effective_mems);
-
-	cpus_updated = !cpumask_equal(&new_cpus, cs->effective_cpus);
-	mems_updated = !nodes_equal(new_mems, cs->effective_mems);
-
-	if (cgroup_subsys_on_dfl(cpuset_cgrp_subsys))
-		hotplug_update_tasks(cs, &new_cpus, &new_mems,
-				     cpus_updated, mems_updated);
-	else
-		hotplug_update_tasks_legacy(cs, &new_cpus, &new_mems,
-					    cpus_updated, mems_updated);
-
-	mutex_unlock(&cpuset_mutex);
-}
-
-/**
- * cpuset_hotplug_workfn - handle CPU/memory hotunplug for a cpuset
- *
- * This function is called after either CPU or memory configuration has
- * changed and updates cpuset accordingly.  The top_cpuset is always
- * synchronized to cpu_active_mask and N_MEMORY, which is necessary in
- * order to make cpusets transparent (of no affect) on systems that are
- * actively using CPU hotplug but making no active use of cpusets.
- *
- * Non-root cpusets are only affected by offlining.  If any CPUs or memory
- * nodes have been taken down, cpuset_hotplug_update_tasks() is invoked on
- * all descendants.
- *
- * Note that CPU offlining during suspend is ignored.  We don't modify
- * cpusets across suspend/resume cycles at all.
- */
-static void cpuset_hotplug_workfn(struct work_struct *work)
-{
-	static cpumask_t new_cpus;
-	static nodemask_t new_mems;
-	bool cpus_updated, mems_updated;
-	bool on_dfl = cgroup_subsys_on_dfl(cpuset_cgrp_subsys);
-
-	mutex_lock(&cpuset_mutex);
-
-	/* fetch the available cpus/mems and find out which changed how */
-	cpumask_copy(&new_cpus, cpu_active_mask);
-	new_mems = node_states[N_MEMORY];
-
-	cpus_updated = !cpumask_equal(top_cpuset.effective_cpus, &new_cpus);
-	mems_updated = !nodes_equal(top_cpuset.effective_mems, new_mems);
-
-	/* synchronize cpus_allowed to cpu_active_mask */
-	if (cpus_updated) {
-		spin_lock_irq(&callback_lock);
-		if (!on_dfl)
-			cpumask_copy(top_cpuset.cpus_allowed, &new_cpus);
-		cpumask_copy(top_cpuset.effective_cpus, &new_cpus);
-		spin_unlock_irq(&callback_lock);
-		/* we don't mess with cpumasks of tasks in top_cpuset */
-	}
-
-	/* synchronize mems_allowed to N_MEMORY */
-	if (mems_updated) {
-		spin_lock_irq(&callback_lock);
-		if (!on_dfl)
-			top_cpuset.mems_allowed = new_mems;
-		top_cpuset.effective_mems = new_mems;
-		spin_unlock_irq(&callback_lock);
-		update_tasks_nodemask(&top_cpuset);
-	}
-
-	mutex_unlock(&cpuset_mutex);
-
-	/* if cpus or mems changed, we need to propagate to descendants */
-	if (cpus_updated || mems_updated) {
-		struct cpuset *cs;
-		struct cgroup_subsys_state *pos_css;
-
-		rcu_read_lock();
-		cpuset_for_each_descendant_pre(cs, pos_css, &top_cpuset) {
-			if (cs == &top_cpuset || !css_tryget_online(&cs->css))
-				continue;
-			rcu_read_unlock();
-
-			cpuset_hotplug_update_tasks(cs);
-
-			rcu_read_lock();
-			css_put(&cs->css);
-		}
-		rcu_read_unlock();
-	}
-
-	/* rebuild sched domains if cpus_allowed has changed */
-	if (cpus_updated)
-		rebuild_sched_domains();
-}
-
-void cpuset_update_active_cpus(bool cpu_online)
-{
-	/*
-	 * We're inside cpu hotplug critical region which usually nests
-	 * inside cgroup synchronization.  Bounce actual hotplug processing
-	 * to a work item to avoid reverse locking order.
-	 *
-	 * We still need to do partition_sched_domains() synchronously;
-	 * otherwise, the scheduler will get confused and put tasks to the
-	 * dead CPU.  Fall back to the default single domain.
-	 * cpuset_hotplug_workfn() will rebuild it as necessary.
-	 */
-	partition_sched_domains(1, NULL, NULL);
-	schedule_work(&cpuset_hotplug_work);
-}
-
-/*
- * Keep top_cpuset.mems_allowed tracking node_states[N_MEMORY].
- * Call this routine anytime after node_states[N_MEMORY] changes.
- * See cpuset_update_active_cpus() for CPU hotplug handling.
- */
-static int cpuset_track_online_nodes(struct notifier_block *self,
-				unsigned long action, void *arg)
-{
-	schedule_work(&cpuset_hotplug_work);
-	return NOTIFY_OK;
-}
-
-static struct notifier_block cpuset_track_online_nodes_nb = {
-	.notifier_call = cpuset_track_online_nodes,
-	.priority = 10,		/* ??! */
-};
-
-/**
- * cpuset_init_smp - initialize cpus_allowed
- *
- * Description: Finish top cpuset after cpu, node maps are initialized
- */
-void __init cpuset_init_smp(void)
-{
-	cpumask_copy(top_cpuset.cpus_allowed, cpu_active_mask);
-	top_cpuset.mems_allowed = node_states[N_MEMORY];
-	top_cpuset.old_mems_allowed = top_cpuset.mems_allowed;
-
-	cpumask_copy(top_cpuset.effective_cpus, cpu_active_mask);
-	top_cpuset.effective_mems = node_states[N_MEMORY];
-
-	register_hotmemory_notifier(&cpuset_track_online_nodes_nb);
-
-	cpuset_migrate_mm_wq = alloc_ordered_workqueue("cpuset_migrate_mm", 0);
-	BUG_ON(!cpuset_migrate_mm_wq);
-}
-
-/**
- * cpuset_cpus_allowed - return cpus_allowed mask from a tasks cpuset.
- * @tsk: pointer to task_struct from which to obtain cpuset->cpus_allowed.
- * @pmask: pointer to struct cpumask variable to receive cpus_allowed set.
- *
- * Description: Returns the cpumask_var_t cpus_allowed of the cpuset
- * attached to the specified @tsk.  Guaranteed to return some non-empty
- * subset of cpu_online_mask, even if this means going outside the
- * tasks cpuset.
- **/
-
-void cpuset_cpus_allowed(struct task_struct *tsk, struct cpumask *pmask)
-{
-	unsigned long flags;
-
-	spin_lock_irqsave(&callback_lock, flags);
-	rcu_read_lock();
-	guarantee_online_cpus(task_cs(tsk), pmask);
-	rcu_read_unlock();
-	spin_unlock_irqrestore(&callback_lock, flags);
-}
-
-void cpuset_cpus_allowed_fallback(struct task_struct *tsk)
-{
-	rcu_read_lock();
-	do_set_cpus_allowed(tsk, task_cs(tsk)->effective_cpus);
-	rcu_read_unlock();
-
-	/*
-	 * We own tsk->cpus_allowed, nobody can change it under us.
-	 *
-	 * But we used cs && cs->cpus_allowed lockless and thus can
-	 * race with cgroup_attach_task() or update_cpumask() and get
-	 * the wrong tsk->cpus_allowed. However, both cases imply the
-	 * subsequent cpuset_change_cpumask()->set_cpus_allowed_ptr()
-	 * which takes task_rq_lock().
-	 *
-	 * If we are called after it dropped the lock we must see all
-	 * changes in tsk_cs()->cpus_allowed. Otherwise we can temporary
-	 * set any mask even if it is not right from task_cs() pov,
-	 * the pending set_cpus_allowed_ptr() will fix things.
-	 *
-	 * select_fallback_rq() will fix things ups and set cpu_possible_mask
-	 * if required.
-	 */
-}
-
-void __init cpuset_init_current_mems_allowed(void)
-{
-	nodes_setall(current->mems_allowed);
-}
-
-/**
- * cpuset_mems_allowed - return mems_allowed mask from a tasks cpuset.
- * @tsk: pointer to task_struct from which to obtain cpuset->mems_allowed.
- *
- * Description: Returns the nodemask_t mems_allowed of the cpuset
- * attached to the specified @tsk.  Guaranteed to return some non-empty
- * subset of node_states[N_MEMORY], even if this means going outside the
- * tasks cpuset.
- **/
-
-nodemask_t cpuset_mems_allowed(struct task_struct *tsk)
-{
-	nodemask_t mask;
-	unsigned long flags;
-
-	spin_lock_irqsave(&callback_lock, flags);
-	rcu_read_lock();
-	guarantee_online_mems(task_cs(tsk), &mask);
-	rcu_read_unlock();
-	spin_unlock_irqrestore(&callback_lock, flags);
-
-	return mask;
-}
-
-/**
- * cpuset_nodemask_valid_mems_allowed - check nodemask vs. curremt mems_allowed
- * @nodemask: the nodemask to be checked
- *
- * Are any of the nodes in the nodemask allowed in current->mems_allowed?
- */
-int cpuset_nodemask_valid_mems_allowed(nodemask_t *nodemask)
-{
-	return nodes_intersects(*nodemask, current->mems_allowed);
-}
-
-/*
- * nearest_hardwall_ancestor() - Returns the nearest mem_exclusive or
- * mem_hardwall ancestor to the specified cpuset.  Call holding
- * callback_lock.  If no ancestor is mem_exclusive or mem_hardwall
- * (an unusual configuration), then returns the root cpuset.
- */
-static struct cpuset *nearest_hardwall_ancestor(struct cpuset *cs)
-{
-	while (!(is_mem_exclusive(cs) || is_mem_hardwall(cs)) && parent_cs(cs))
-		cs = parent_cs(cs);
-	return cs;
-}
-
-/**
- * cpuset_node_allowed - Can we allocate on a memory node?
- * @node: is this an allowed node?
- * @gfp_mask: memory allocation flags
- *
- * If we're in interrupt, yes, we can always allocate.  If @node is set in
- * current's mems_allowed, yes.  If it's not a __GFP_HARDWALL request and this
- * node is set in the nearest hardwalled cpuset ancestor to current's cpuset,
- * yes.  If current has access to memory reserves due to TIF_MEMDIE, yes.
- * Otherwise, no.
- *
- * GFP_USER allocations are marked with the __GFP_HARDWALL bit,
- * and do not allow allocations outside the current tasks cpuset
- * unless the task has been OOM killed as is marked TIF_MEMDIE.
- * GFP_KERNEL allocations are not so marked, so can escape to the
- * nearest enclosing hardwalled ancestor cpuset.
- *
- * Scanning up parent cpusets requires callback_lock.  The
- * __alloc_pages() routine only calls here with __GFP_HARDWALL bit
- * _not_ set if it's a GFP_KERNEL allocation, and all nodes in the
- * current tasks mems_allowed came up empty on the first pass over
- * the zonelist.  So only GFP_KERNEL allocations, if all nodes in the
- * cpuset are short of memory, might require taking the callback_lock.
- *
- * The first call here from mm/page_alloc:get_page_from_freelist()
- * has __GFP_HARDWALL set in gfp_mask, enforcing hardwall cpusets,
- * so no allocation on a node outside the cpuset is allowed (unless
- * in interrupt, of course).
- *
- * The second pass through get_page_from_freelist() doesn't even call
- * here for GFP_ATOMIC calls.  For those calls, the __alloc_pages()
- * variable 'wait' is not set, and the bit ALLOC_CPUSET is not set
- * in alloc_flags.  That logic and the checks below have the combined
- * affect that:
- *	in_interrupt - any node ok (current task context irrelevant)
- *	GFP_ATOMIC   - any node ok
- *	TIF_MEMDIE   - any node ok
- *	GFP_KERNEL   - any node in enclosing hardwalled cpuset ok
- *	GFP_USER     - only nodes in current tasks mems allowed ok.
- */
-bool __cpuset_node_allowed(int node, gfp_t gfp_mask)
-{
-	struct cpuset *cs;		/* current cpuset ancestors */
-	int allowed;			/* is allocation in zone z allowed? */
-	unsigned long flags;
-
-	if (in_interrupt())
-		return true;
-	if (node_isset(node, current->mems_allowed))
-		return true;
-	/*
-	 * Allow tasks that have access to memory reserves because they have
-	 * been OOM killed to get memory anywhere.
-	 */
-	if (unlikely(test_thread_flag(TIF_MEMDIE)))
-		return true;
-	if (gfp_mask & __GFP_HARDWALL)	/* If hardwall request, stop here */
-		return false;
-
-	if (current->flags & PF_EXITING) /* Let dying task have memory */
-		return true;
-
-	/* Not hardwall and node outside mems_allowed: scan up cpusets */
-	spin_lock_irqsave(&callback_lock, flags);
-
-	rcu_read_lock();
-	cs = nearest_hardwall_ancestor(task_cs(current));
-	allowed = node_isset(node, cs->mems_allowed);
-	rcu_read_unlock();
-
-	spin_unlock_irqrestore(&callback_lock, flags);
-	return allowed;
-}
-
-/**
- * cpuset_mem_spread_node() - On which node to begin search for a file page
- * cpuset_slab_spread_node() - On which node to begin search for a slab page
- *
- * If a task is marked PF_SPREAD_PAGE or PF_SPREAD_SLAB (as for
- * tasks in a cpuset with is_spread_page or is_spread_slab set),
- * and if the memory allocation used cpuset_mem_spread_node()
- * to determine on which node to start looking, as it will for
- * certain page cache or slab cache pages such as used for file
- * system buffers and inode caches, then instead of starting on the
- * local node to look for a free page, rather spread the starting
- * node around the tasks mems_allowed nodes.
- *
- * We don't have to worry about the returned node being offline
- * because "it can't happen", and even if it did, it would be ok.
- *
- * The routines calling guarantee_online_mems() are careful to
- * only set nodes in task->mems_allowed that are online.  So it
- * should not be possible for the following code to return an
- * offline node.  But if it did, that would be ok, as this routine
- * is not returning the node where the allocation must be, only
- * the node where the search should start.  The zonelist passed to
- * __alloc_pages() will include all nodes.  If the slab allocator
- * is passed an offline node, it will fall back to the local node.
- * See kmem_cache_alloc_node().
- */
-
-static int cpuset_spread_node(int *rotor)
-{
-	return *rotor = next_node_in(*rotor, current->mems_allowed);
-}
-
-int cpuset_mem_spread_node(void)
-{
-	if (current->cpuset_mem_spread_rotor == NUMA_NO_NODE)
-		current->cpuset_mem_spread_rotor =
-			node_random(&current->mems_allowed);
-
-	return cpuset_spread_node(&current->cpuset_mem_spread_rotor);
-}
-
-int cpuset_slab_spread_node(void)
-{
-	if (current->cpuset_slab_spread_rotor == NUMA_NO_NODE)
-		current->cpuset_slab_spread_rotor =
-			node_random(&current->mems_allowed);
-
-	return cpuset_spread_node(&current->cpuset_slab_spread_rotor);
-}
-
-EXPORT_SYMBOL_GPL(cpuset_mem_spread_node);
-
-/**
- * cpuset_mems_allowed_intersects - Does @tsk1's mems_allowed intersect @tsk2's?
- * @tsk1: pointer to task_struct of some task.
- * @tsk2: pointer to task_struct of some other task.
- *
- * Description: Return true if @tsk1's mems_allowed intersects the
- * mems_allowed of @tsk2.  Used by the OOM killer to determine if
- * one of the task's memory usage might impact the memory available
- * to the other.
- **/
-
-int cpuset_mems_allowed_intersects(const struct task_struct *tsk1,
-				   const struct task_struct *tsk2)
-{
-	return nodes_intersects(tsk1->mems_allowed, tsk2->mems_allowed);
-}
-
-/**
- * cpuset_print_current_mems_allowed - prints current's cpuset and mems_allowed
- *
- * Description: Prints current's name, cpuset name, and cached copy of its
- * mems_allowed to the kernel log.
- */
-void cpuset_print_current_mems_allowed(void)
-{
-	struct cgroup *cgrp;
-
-	rcu_read_lock();
-
-	cgrp = task_cs(current)->css.cgroup;
-	pr_info("%s cpuset=", current->comm);
-	pr_cont_cgroup_name(cgrp);
-	pr_cont(" mems_allowed=%*pbl\n",
-		nodemask_pr_args(&current->mems_allowed));
-
-	rcu_read_unlock();
-}
-
-/*
- * Collection of memory_pressure is suppressed unless
- * this flag is enabled by writing "1" to the special
- * cpuset file 'memory_pressure_enabled' in the root cpuset.
- */
-
-int cpuset_memory_pressure_enabled __read_mostly;
-
-/**
- * cpuset_memory_pressure_bump - keep stats of per-cpuset reclaims.
- *
- * Keep a running average of the rate of synchronous (direct)
- * page reclaim efforts initiated by tasks in each cpuset.
- *
- * This represents the rate at which some task in the cpuset
- * ran low on memory on all nodes it was allowed to use, and
- * had to enter the kernels page reclaim code in an effort to
- * create more free memory by tossing clean pages or swapping
- * or writing dirty pages.
- *
- * Display to user space in the per-cpuset read-only file
- * "memory_pressure".  Value displayed is an integer
- * representing the recent rate of entry into the synchronous
- * (direct) page reclaim by any task attached to the cpuset.
- **/
-
-void __cpuset_memory_pressure_bump(void)
-{
-	rcu_read_lock();
-	fmeter_markevent(&task_cs(current)->fmeter);
-	rcu_read_unlock();
-}
-
-#ifdef CONFIG_PROC_PID_CPUSET
-/*
- * proc_cpuset_show()
- *  - Print tasks cpuset path into seq_file.
- *  - Used for /proc/<pid>/cpuset.
- *  - No need to task_lock(tsk) on this tsk->cpuset reference, as it
- *    doesn't really matter if tsk->cpuset changes after we read it,
- *    and we take cpuset_mutex, keeping cpuset_attach() from changing it
- *    anyway.
- */
-int proc_cpuset_show(struct seq_file *m, struct pid_namespace *ns,
-		     struct pid *pid, struct task_struct *tsk)
-{
-	char *buf;
-	struct cgroup_subsys_state *css;
-	int retval;
-
-	retval = -ENOMEM;
-	buf = kmalloc(PATH_MAX, GFP_KERNEL);
-	if (!buf)
-		goto out;
-
-	css = task_get_css(tsk, cpuset_cgrp_id);
-	retval = cgroup_path_ns(css->cgroup, buf, PATH_MAX,
-				current->nsproxy->cgroup_ns);
-	css_put(css);
-	if (retval >= PATH_MAX)
-		retval = -ENAMETOOLONG;
-	if (retval < 0)
-		goto out_free;
-	seq_puts(m, buf);
-	seq_putc(m, '\n');
-	retval = 0;
-out_free:
-	kfree(buf);
-out:
-	return retval;
-}
-#endif /* CONFIG_PROC_PID_CPUSET */
-
-/* Display task mems_allowed in /proc/<pid>/status file. */
-void cpuset_task_status_allowed(struct seq_file *m, struct task_struct *task)
-{
-	seq_printf(m, "Mems_allowed:\t%*pb\n",
-		   nodemask_pr_args(&task->mems_allowed));
-	seq_printf(m, "Mems_allowed_list:\t%*pbl\n",
-		   nodemask_pr_args(&task->mems_allowed));
-}