[PATCH v2 -next 00/11] cgroup:cpuset:separate legacy cgroup v1 code and put under config option

[PATCH v2 -next 00/11] cgroup:cpuset:separate legacy cgroup v1 code and put under config option

[Chen Ridong]

Cgroups v2 have been around for a while and many users have fully adopted
them, so they never use cgroups v1 features and functionality. Yet they
have to "pay" for the cgroup v1 support anyway:
1) the kernel binary contains an unused cgroup v1 code,
2) some code paths have additional checks which are not needed,
3) some common structures like task_struct and mem_cgroup contain unused
   cgroup v1-specific members.

Cgroup memory controller has already separated legacy code to
memory-v1.c. So it is time to do the same thing for cpuset controller.

This patchset aims to do:
1) moving cgroup v1-specific cpuset code to the new cpuset-v1.c file,
2) putting definitions shared by cpuset.c and cpuset-v1.c into the
   cpuset-internal.h header,
3) introducing the CONFIG_CPUSETS_V1 config option, turned off by default,
4) making cpuset-v1.c to compile only if CONFIG_CPUSETS_V1 is set.

---
V2:
- Update to base on the latest cgroup/for-6.12.
- Add CONFIG_CPUSETS_V1 for cpuset_memory_pressure_bump.

Chen Ridong (11):
  cgroup/cpuset: introduce cpuset-v1.c
  cgroup/cpuset: move common code to cpuset-internal.h
  cgroup/cpuset: move memory_pressure to cpuset-v1.c
  cgroup/cpuset: move relax_domain_level to cpuset-v1.c
  cgroup/cpuset: move memory_spread to cpuset-v1.c
  cgroup/cpuset: add callback_lock helper
  cgroup/cpuset: move legacy hotplug update to cpuset-v1.c
  cgroup/cpuset: move validate_change_legacy to cpuset-v1.c
  cgroup/cpuset: move v1 interfaces to cpuset-v1.c
  cgroup/cpuset: guard cpuset-v1 code under CONFIG_CPUSETS_V1
  cgroup/cpuset: add sefltest for cpuset v1

 MAINTAINERS                                   |   3 +
 include/linux/cpuset.h                        |   4 +
 init/Kconfig                                  |  13 +
 kernel/cgroup/Makefile                        |   1 +
 kernel/cgroup/cpuset-internal.h               | 305 +++++++
 kernel/cgroup/cpuset-v1.c                     | 563 ++++++++++++
 kernel/cgroup/cpuset.c                        | 850 +-----------------
 .../selftests/cgroup/test_cpuset_v1_base.sh   |  77 ++
 8 files changed, 986 insertions(+), 830 deletions(-)
 create mode 100644 kernel/cgroup/cpuset-internal.h
 create mode 100644 kernel/cgroup/cpuset-v1.c
 create mode 100755 tools/testing/selftests/cgroup/test_cpuset_v1_base.sh

-- 
2.34.1

[PATCH v2 -next 01/11] cgroup/cpuset: introduce cpuset-v1.c

[Chen Ridong]

This patch introduces the cgroup/cpuset-v1.c source file which will be
used for all legacy (cgroup v1) cpuset cgroup code. It also introduces
cgroup/cpuset-internal.h to keep declarations shared between
cgroup/cpuset.c and cpuset/cpuset-v1.c.

As of now, let's compile it if CONFIG_CPUSET is set. Later on it can be
switched to use a separate config option, so that the legacy code won't be
compiled if not required.

Signed-off-by: Chen Ridong <chenridong@huawei.com>
---
 MAINTAINERS                     | 2 ++
 kernel/cgroup/Makefile          | 2 +-
 kernel/cgroup/cpuset-internal.h | 7 +++++++
 kernel/cgroup/cpuset-v1.c       | 4 ++++
 4 files changed, 14 insertions(+), 1 deletion(-)
 create mode 100644 kernel/cgroup/cpuset-internal.h
 create mode 100644 kernel/cgroup/cpuset-v1.c

diff --git a/MAINTAINERS b/MAINTAINERS
index 82e3924816d2..3b5ec1cafd95 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -5698,6 +5698,8 @@ S:	Maintained
 T:	git git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup.git
 F:	Documentation/admin-guide/cgroup-v1/cpusets.rst
 F:	include/linux/cpuset.h
+F:	kernel/cgroup/cpuset-internal.h
+F:	kernel/cgroup/cpuset-v1.c
 F:	kernel/cgroup/cpuset.c
 F:	tools/testing/selftests/cgroup/test_cpuset.c
 F:	tools/testing/selftests/cgroup/test_cpuset_prs.sh
diff --git a/kernel/cgroup/Makefile b/kernel/cgroup/Makefile
index 12f8457ad1f9..005ac4c675cb 100644
--- a/kernel/cgroup/Makefile
+++ b/kernel/cgroup/Makefile
@@ -4,6 +4,6 @@ obj-y := cgroup.o rstat.o namespace.o cgroup-v1.o freezer.o
 obj-$(CONFIG_CGROUP_FREEZER) += legacy_freezer.o
 obj-$(CONFIG_CGROUP_PIDS) += pids.o
 obj-$(CONFIG_CGROUP_RDMA) += rdma.o
-obj-$(CONFIG_CPUSETS) += cpuset.o
+obj-$(CONFIG_CPUSETS) += cpuset.o cpuset-v1.o
 obj-$(CONFIG_CGROUP_MISC) += misc.o
 obj-$(CONFIG_CGROUP_DEBUG) += debug.o
diff --git a/kernel/cgroup/cpuset-internal.h b/kernel/cgroup/cpuset-internal.h
new file mode 100644
index 000000000000..6605be417e32
--- /dev/null
+++ b/kernel/cgroup/cpuset-internal.h
@@ -0,0 +1,7 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+
+#ifndef __CPUSET_INTERNAL_H
+#define __CPUSET_INTERNAL_H
+
+#endif /* __CPUSET_INTERNAL_H */
+
diff --git a/kernel/cgroup/cpuset-v1.c b/kernel/cgroup/cpuset-v1.c
new file mode 100644
index 000000000000..ae166eb4f75d
--- /dev/null
+++ b/kernel/cgroup/cpuset-v1.c
@@ -0,0 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#include "cpuset-internal.h"
+
-- 
2.34.1

[PATCH v2 -next 02/11] cgroup/cpuset: move common code to cpuset-internal.h

[Chen Ridong]

Move some declarations that will be used for cpuset v1 and v2,
including 'cpuset struct', 'cpuset_flagbits_t', cpuset_filetype_t,etc.
No logical change.

Signed-off-by: Chen Ridong <chenridong@huawei.com>
---
 kernel/cgroup/cpuset-internal.h | 236 +++++++++++++++++++++++++++++++-
 kernel/cgroup/cpuset.c          | 236 +-------------------------------
 2 files changed, 236 insertions(+), 236 deletions(-)

diff --git a/kernel/cgroup/cpuset-internal.h b/kernel/cgroup/cpuset-internal.h
index 6605be417e32..ffea3eefebdf 100644
--- a/kernel/cgroup/cpuset-internal.h
+++ b/kernel/cgroup/cpuset-internal.h
@@ -3,5 +3,239 @@
 #ifndef __CPUSET_INTERNAL_H
 #define __CPUSET_INTERNAL_H
 
-#endif /* __CPUSET_INTERNAL_H */
+#include <linux/union_find.h>
+#include <linux/cpumask.h>
+#include <linux/spinlock.h>
+#include <linux/cpuset.h>
+#include <linux/cgroup.h>
+
+/* 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 */
+};
+
+/*
+ * Invalid partition error code
+ */
+enum prs_errcode {
+	PERR_NONE = 0,
+	PERR_INVCPUS,
+	PERR_INVPARENT,
+	PERR_NOTPART,
+	PERR_NOTEXCL,
+	PERR_NOCPUS,
+	PERR_HOTPLUG,
+	PERR_CPUSEMPTY,
+	PERR_HKEEPING,
+	PERR_ACCESS,
+};
+
+/* 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;
+
+/* 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_SUBPARTS_CPULIST,
+	FILE_EXCLUSIVE_CPULIST,
+	FILE_EFFECTIVE_XCPULIST,
+	FILE_ISOLATED_CPULIST,
+	FILE_CPU_EXCLUSIVE,
+	FILE_MEM_EXCLUSIVE,
+	FILE_MEM_HARDWALL,
+	FILE_SCHED_LOAD_BALANCE,
+	FILE_PARTITION_ROOT,
+	FILE_SCHED_RELAX_DOMAIN_LEVEL,
+	FILE_MEMORY_PRESSURE_ENABLED,
+	FILE_MEMORY_PRESSURE,
+	FILE_SPREAD_PAGE,
+	FILE_SPREAD_SLAB,
+} cpuset_filetype_t;
+
+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 hierarchy:
+	 *
+	 * 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;
+
+	/*
+	 * Exclusive CPUs dedicated to current cgroup (default hierarchy only)
+	 *
+	 * The effective_cpus of a valid partition root comes solely from its
+	 * effective_xcpus and some of the effective_xcpus may be distributed
+	 * to sub-partitions below & hence excluded from its effective_cpus.
+	 * For a valid partition root, its effective_cpus have no relationship
+	 * with cpus_allowed unless its exclusive_cpus isn't set.
+	 *
+	 * This value will only be set if either exclusive_cpus is set or
+	 * when this cpuset becomes a local partition root.
+	 */
+	cpumask_var_t effective_xcpus;
+
+	/*
+	 * Exclusive CPUs as requested by the user (default hierarchy only)
+	 *
+	 * Its value is independent of cpus_allowed and designates the set of
+	 * CPUs that can be granted to the current cpuset or its children when
+	 * it becomes a valid partition root. The effective set of exclusive
+	 * CPUs granted (effective_xcpus) depends on whether those exclusive
+	 * CPUs are passed down by its ancestors and not yet taken up by
+	 * another sibling partition root along the way.
+	 *
+	 * If its value isn't set, it defaults to cpus_allowed.
+	 */
+	cpumask_var_t exclusive_cpus;
+
+	/*
+	 * 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;
+
+	/* for custom sched domain */
+	int relax_domain_level;
+
+	/* number of valid local child partitions */
+	int nr_subparts;
 
+	/* partition root state */
+	int partition_root_state;
+
+	/*
+	 * number of SCHED_DEADLINE tasks attached to this cpuset, so that we
+	 * know when to rebuild associated root domain bandwidth information.
+	 */
+	int nr_deadline_tasks;
+	int nr_migrate_dl_tasks;
+	u64 sum_migrate_dl_bw;
+
+	/* Invalid partition error code, not lock protected */
+	enum prs_errcode prs_err;
+
+	/* Handle for cpuset.cpus.partition */
+	struct cgroup_file partition_file;
+
+	/* Remote partition silbling list anchored at remote_children */
+	struct list_head remote_sibling;
+
+	/* Used to merge intersecting subsets for generate_sched_domains */
+	struct uf_node node;
+};
+
+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);
+}
+
+/* convenient tests for these bits */
+static inline bool is_cpuset_online(struct cpuset *cs)
+{
+	return test_bit(CS_ONLINE, &cs->flags) && !css_is_dying(&cs->css);
+}
+
+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);
+}
+
+#endif /* __CPUSET_INTERNAL_H */
diff --git a/kernel/cgroup/cpuset.c b/kernel/cgroup/cpuset.c
index 7db55eed63cf..61763dd70de5 100644
--- a/kernel/cgroup/cpuset.c
+++ b/kernel/cgroup/cpuset.c
@@ -22,11 +22,9 @@
  *  distribution for more details.
  */
 #include "cgroup-internal.h"
+#include "cpuset-internal.h"
 
 #include <linux/cpu.h>
-#include <linux/cpumask.h>
-#include <linux/cpuset.h>
-#include <linux/delay.h>
 #include <linux/init.h>
 #include <linux/interrupt.h>
 #include <linux/kernel.h>
@@ -40,13 +38,10 @@
 #include <linux/sched/mm.h>
 #include <linux/sched/task.h>
 #include <linux/security.h>
-#include <linux/spinlock.h>
 #include <linux/oom.h>
 #include <linux/sched/isolation.h>
-#include <linux/cgroup.h>
 #include <linux/wait.h>
 #include <linux/workqueue.h>
-#include <linux/union_find.h>
 
 DEFINE_STATIC_KEY_FALSE(cpusets_pre_enable_key);
 DEFINE_STATIC_KEY_FALSE(cpusets_enabled_key);
@@ -58,31 +53,6 @@ DEFINE_STATIC_KEY_FALSE(cpusets_enabled_key);
  */
 DEFINE_STATIC_KEY_FALSE(cpusets_insane_config_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 */
-};
-
-/*
- * Invalid partition error code
- */
-enum prs_errcode {
-	PERR_NONE = 0,
-	PERR_INVCPUS,
-	PERR_INVPARENT,
-	PERR_NOTPART,
-	PERR_NOTEXCL,
-	PERR_NOCPUS,
-	PERR_HOTPLUG,
-	PERR_CPUSEMPTY,
-	PERR_HKEEPING,
-	PERR_ACCESS,
-};
-
 static const char * const perr_strings[] = {
 	[PERR_INVCPUS]   = "Invalid cpu list in cpuset.cpus.exclusive",
 	[PERR_INVPARENT] = "Parent is an invalid partition root",
@@ -95,117 +65,6 @@ static const char * const perr_strings[] = {
 	[PERR_ACCESS]    = "Enable partition not permitted",
 };
 
-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 hierarchy:
-	 *
-	 * 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;
-
-	/*
-	 * Exclusive CPUs dedicated to current cgroup (default hierarchy only)
-	 *
-	 * The effective_cpus of a valid partition root comes solely from its
-	 * effective_xcpus and some of the effective_xcpus may be distributed
-	 * to sub-partitions below & hence excluded from its effective_cpus.
-	 * For a valid partition root, its effective_cpus have no relationship
-	 * with cpus_allowed unless its exclusive_cpus isn't set.
-	 *
-	 * This value will only be set if either exclusive_cpus is set or
-	 * when this cpuset becomes a local partition root.
-	 */
-	cpumask_var_t effective_xcpus;
-
-	/*
-	 * Exclusive CPUs as requested by the user (default hierarchy only)
-	 *
-	 * Its value is independent of cpus_allowed and designates the set of
-	 * CPUs that can be granted to the current cpuset or its children when
-	 * it becomes a valid partition root. The effective set of exclusive
-	 * CPUs granted (effective_xcpus) depends on whether those exclusive
-	 * CPUs are passed down by its ancestors and not yet taken up by
-	 * another sibling partition root along the way.
-	 *
-	 * If its value isn't set, it defaults to cpus_allowed.
-	 */
-	cpumask_var_t exclusive_cpus;
-
-	/*
-	 * 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;
-
-	/* for custom sched domain */
-	int relax_domain_level;
-
-	/* number of valid local child partitions */
-	int nr_subparts;
-
-	/* partition root state */
-	int partition_root_state;
-
-	/*
-	 * number of SCHED_DEADLINE tasks attached to this cpuset, so that we
-	 * know when to rebuild associated root domain bandwidth information.
-	 */
-	int nr_deadline_tasks;
-	int nr_migrate_dl_tasks;
-	u64 sum_migrate_dl_bw;
-
-	/* Invalid partition error code, not lock protected */
-	enum prs_errcode prs_err;
-
-	/* Handle for cpuset.cpus.partition */
-	struct cgroup_file partition_file;
-
-	/* Remote partition silbling list anchored at remote_children */
-	struct list_head remote_sibling;
-
-	/* Used to merge intersecting subsets for generate_sched_domains */
-	struct uf_node node;
-};
-
 /*
  * Legacy hierarchy call to cgroup_transfer_tasks() is handled asynchrously
  */
@@ -274,22 +133,6 @@ struct tmpmasks {
 	cpumask_var_t new_cpus;		/* For update_cpumasks_hier() */
 };
 
-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);
-}
-
 void inc_dl_tasks_cs(struct task_struct *p)
 {
 	struct cpuset *cs = task_cs(p);
@@ -304,59 +147,6 @@ void dec_dl_tasks_cs(struct task_struct *p)
 	cs->nr_deadline_tasks--;
 }
 
-/* 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(struct cpuset *cs)
-{
-	return test_bit(CS_ONLINE, &cs->flags) && !css_is_dying(&cs->css);
-}
-
-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 inline int is_partition_valid(const struct cpuset *cs)
 {
 	return cs->partition_root_state > 0;
@@ -3529,30 +3319,6 @@ static void cpuset_attach(struct cgroup_taskset *tset)
 	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_SUBPARTS_CPULIST,
-	FILE_EXCLUSIVE_CPULIST,
-	FILE_EFFECTIVE_XCPULIST,
-	FILE_ISOLATED_CPULIST,
-	FILE_CPU_EXCLUSIVE,
-	FILE_MEM_EXCLUSIVE,
-	FILE_MEM_HARDWALL,
-	FILE_SCHED_LOAD_BALANCE,
-	FILE_PARTITION_ROOT,
-	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)
 {
-- 
2.34.1

[PATCH v2 -next 03/11] cgroup/cpuset: move memory_pressure to cpuset-v1.c

[Chen Ridong]

Collection of memory_pressure can be enabled by writing 1 to the cpuset
file 'memory_pressure_enabled', which is only for cpuset-v1. Therefore,
move the corresponding code to cpuset-v1.c.

Currently, the 'fmeter_init' and 'fmeter_getrate' functions are called
at cpuset.c, so expose them to cpuset.c.

Signed-off-by: Chen Ridong <chenridong@huawei.com>
---
 kernel/cgroup/cpuset-internal.h |   7 ++
 kernel/cgroup/cpuset-v1.c       | 134 ++++++++++++++++++++++++++++++++
 kernel/cgroup/cpuset.c          | 134 --------------------------------
 3 files changed, 141 insertions(+), 134 deletions(-)

diff --git a/kernel/cgroup/cpuset-internal.h b/kernel/cgroup/cpuset-internal.h
index ffea3eefebdf..7911c86bf012 100644
--- a/kernel/cgroup/cpuset-internal.h
+++ b/kernel/cgroup/cpuset-internal.h
@@ -238,4 +238,11 @@ static inline int is_spread_slab(const struct cpuset *cs)
 	return test_bit(CS_SPREAD_SLAB, &cs->flags);
 }
 
+/*
+ * cpuset-v1.c
+ */
+
+void fmeter_init(struct fmeter *fmp);
+int fmeter_getrate(struct fmeter *fmp);
+
 #endif /* __CPUSET_INTERNAL_H */
diff --git a/kernel/cgroup/cpuset-v1.c b/kernel/cgroup/cpuset-v1.c
index ae166eb4f75d..f17ba44bc566 100644
--- a/kernel/cgroup/cpuset-v1.c
+++ b/kernel/cgroup/cpuset-v1.c
@@ -2,3 +2,137 @@
 
 #include "cpuset-internal.h"
 
+/*
+ * 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 */
+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. */
+int fmeter_getrate(struct fmeter *fmp)
+{
+	int val;
+
+	spin_lock(&fmp->lock);
+	fmeter_update(fmp);
+	val = fmp->val;
+	spin_unlock(&fmp->lock);
+	return val;
+}
+
+/*
+ * 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();
+}
+
diff --git a/kernel/cgroup/cpuset.c b/kernel/cgroup/cpuset.c
index 61763dd70de5..17f7984a41f5 100644
--- a/kernel/cgroup/cpuset.c
+++ b/kernel/cgroup/cpuset.c
@@ -2990,107 +2990,6 @@ static int update_prstate(struct cpuset *cs, int new_prs)
 	return 0;
 }
 
-/*
- * 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;
 
 /*
@@ -4780,39 +4679,6 @@ void cpuset_print_current_mems_allowed(void)
 	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()
-- 
2.34.1

[PATCH v2 -next 04/11] cgroup/cpuset: move relax_domain_level to cpuset-v1.c

[Chen Ridong]

Setting domain level is not supported at cpuset v2, so move corresponding
code into cpuset-v1.c.

The 'cpuset_write_s64' and 'cpuset_read_s64' are only used for setting
domain level, move them to cpuset-v1.c. Currently, expose to cpuset.c.
After cpuset legacy interface files are move to cpuset-v1.c, they can
be static. The 'rebuild_sched_domains_locked' is exposed to cpuset-v1.c.

The change from original code is that using 'cpuset_lock' and
'cpuset_unlock' functions to lock or unlock cpuset_mutex.

Signed-off-by: Chen Ridong <chenridong@huawei.com>
---
 kernel/cgroup/cpuset-internal.h |  6 +++-
 kernel/cgroup/cpuset-v1.c       | 59 +++++++++++++++++++++++++++++++
 kernel/cgroup/cpuset.c          | 62 ++-------------------------------
 3 files changed, 66 insertions(+), 61 deletions(-)

diff --git a/kernel/cgroup/cpuset-internal.h b/kernel/cgroup/cpuset-internal.h
index 7911c86bf012..1058a45f05ec 100644
--- a/kernel/cgroup/cpuset-internal.h
+++ b/kernel/cgroup/cpuset-internal.h
@@ -238,11 +238,15 @@ static inline int is_spread_slab(const struct cpuset *cs)
 	return test_bit(CS_SPREAD_SLAB, &cs->flags);
 }
 
+void rebuild_sched_domains_locked(void);
+
 /*
  * cpuset-v1.c
  */
-
 void fmeter_init(struct fmeter *fmp);
 int fmeter_getrate(struct fmeter *fmp);
+int cpuset_write_s64(struct cgroup_subsys_state *css, struct cftype *cft,
+			    s64 val);
+s64 cpuset_read_s64(struct cgroup_subsys_state *css, struct cftype *cft);
 
 #endif /* __CPUSET_INTERNAL_H */
diff --git a/kernel/cgroup/cpuset-v1.c b/kernel/cgroup/cpuset-v1.c
index f17ba44bc566..175638f2e7b7 100644
--- a/kernel/cgroup/cpuset-v1.c
+++ b/kernel/cgroup/cpuset-v1.c
@@ -136,3 +136,62 @@ void __cpuset_memory_pressure_bump(void)
 	rcu_read_unlock();
 }
 
+static int update_relax_domain_level(struct cpuset *cs, s64 val)
+{
+#ifdef CONFIG_SMP
+	if (val < -1 || val > sched_domain_level_max + 1)
+		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;
+}
+
+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;
+
+	cpus_read_lock();
+	cpuset_lock();
+	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:
+	cpuset_unlock();
+	cpus_read_unlock();
+	return retval;
+}
+
+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();
+	}
+
+	/* Unreachable but makes gcc happy */
+	return 0;
+}
+
diff --git a/kernel/cgroup/cpuset.c b/kernel/cgroup/cpuset.c
index 17f7984a41f5..45031a17e068 100644
--- a/kernel/cgroup/cpuset.c
+++ b/kernel/cgroup/cpuset.c
@@ -1069,7 +1069,7 @@ partition_and_rebuild_sched_domains(int ndoms_new, cpumask_var_t doms_new[],
  *
  * Call with cpuset_mutex held.  Takes cpus_read_lock().
  */
-static void rebuild_sched_domains_locked(void)
+void rebuild_sched_domains_locked(void)
 {
 	struct cgroup_subsys_state *pos_css;
 	struct sched_domain_attr *attr;
@@ -1121,7 +1121,7 @@ static void rebuild_sched_domains_locked(void)
 	partition_and_rebuild_sched_domains(ndoms, doms, attr);
 }
 #else /* !CONFIG_SMP */
-static void rebuild_sched_domains_locked(void)
+void rebuild_sched_domains_locked(void)
 {
 }
 #endif /* CONFIG_SMP */
@@ -2788,23 +2788,6 @@ bool current_cpuset_is_being_rebound(void)
 	return ret;
 }
 
-static int update_relax_domain_level(struct cpuset *cs, s64 val)
-{
-#ifdef CONFIG_SMP
-	if (val < -1 || val > sched_domain_level_max + 1)
-		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
@@ -3267,32 +3250,6 @@ static int cpuset_write_u64(struct cgroup_subsys_state *css, struct cftype *cft,
 	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;
-
-	cpus_read_lock();
-	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);
-	cpus_read_unlock();
-	return retval;
-}
-
 /*
  * Common handling for a write to a "cpus" or "mems" file.
  */
@@ -3443,21 +3400,6 @@ static u64 cpuset_read_u64(struct cgroup_subsys_state *css, struct cftype *cft)
 	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();
-	}
-
-	/* Unreachable but makes gcc happy */
-	return 0;
-}
-
 static int sched_partition_show(struct seq_file *seq, void *v)
 {
 	struct cpuset *cs = css_cs(seq_css(seq));
-- 
2.34.1

[PATCH v2 -next 05/11] cgroup/cpuset: move memory_spread to cpuset-v1.c

[Chen Ridong]

'memory_spread' is only set in cpuset v1. move corresponding code into
cpuset-v1.c.

Currently, 'cpuset_update_task_spread_flags' and 'update_tasks_flags' are
exposed to cpuset.c.

Signed-off-by: Chen Ridong <chenridong@huawei.com>
---
 kernel/cgroup/cpuset-internal.h |  3 +++
 kernel/cgroup/cpuset-v1.c       | 42 +++++++++++++++++++++++++++++++++
 kernel/cgroup/cpuset.c          | 42 ---------------------------------
 3 files changed, 45 insertions(+), 42 deletions(-)

diff --git a/kernel/cgroup/cpuset-internal.h b/kernel/cgroup/cpuset-internal.h
index 1058a45f05ec..02c4b0c74fa9 100644
--- a/kernel/cgroup/cpuset-internal.h
+++ b/kernel/cgroup/cpuset-internal.h
@@ -248,5 +248,8 @@ int fmeter_getrate(struct fmeter *fmp);
 int cpuset_write_s64(struct cgroup_subsys_state *css, struct cftype *cft,
 			    s64 val);
 s64 cpuset_read_s64(struct cgroup_subsys_state *css, struct cftype *cft);
+void cpuset_update_task_spread_flags(struct cpuset *cs,
+					struct task_struct *tsk);
+void update_tasks_flags(struct cpuset *cs);
 
 #endif /* __CPUSET_INTERNAL_H */
diff --git a/kernel/cgroup/cpuset-v1.c b/kernel/cgroup/cpuset-v1.c
index 175638f2e7b7..320abd4bf2c3 100644
--- a/kernel/cgroup/cpuset-v1.c
+++ b/kernel/cgroup/cpuset-v1.c
@@ -195,3 +195,45 @@ s64 cpuset_read_s64(struct cgroup_subsys_state *css, struct cftype *cft)
 	return 0;
 }
 
+/*
+ * update task's spread flag if cpuset's page/slab spread flag is set
+ *
+ * Call with callback_lock or cpuset_mutex held. The check can be skipped
+ * if on default hierarchy.
+ */
+void cpuset_update_task_spread_flags(struct cpuset *cs,
+					struct task_struct *tsk)
+{
+	if (cgroup_subsys_on_dfl(cpuset_cgrp_subsys))
+		return;
+
+	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);
+}
+
+/**
+ * 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.
+ */
+void update_tasks_flags(struct cpuset *cs)
+{
+	struct css_task_iter it;
+	struct task_struct *task;
+
+	css_task_iter_start(&cs->css, 0, &it);
+	while ((task = css_task_iter_next(&it)))
+		cpuset_update_task_spread_flags(cs, task);
+	css_task_iter_end(&it);
+}
+
diff --git a/kernel/cgroup/cpuset.c b/kernel/cgroup/cpuset.c
index 45031a17e068..0a3347e4dddc 100644
--- a/kernel/cgroup/cpuset.c
+++ b/kernel/cgroup/cpuset.c
@@ -401,29 +401,6 @@ static void guarantee_online_mems(struct cpuset *cs, nodemask_t *pmask)
 	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. The check can be skipped
- * if on default hierarchy.
- */
-static void cpuset_update_task_spread_flags(struct cpuset *cs,
-					struct task_struct *tsk)
-{
-	if (cgroup_subsys_on_dfl(cpuset_cgrp_subsys))
-		return;
-
-	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?
  *
@@ -2788,25 +2765,6 @@ bool current_cpuset_is_being_rebound(void)
 	return ret;
 }
 
-/**
- * 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, 0, &it);
-	while ((task = css_task_iter_next(&it)))
-		cpuset_update_task_spread_flags(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)
-- 
2.34.1

[PATCH v2 -next 06/11] cgroup/cpuset: add callback_lock helper

[Chen Ridong]

To modify cpuset, both cpuset_mutex and callback_lock are needed. Add
helpers for cpuset-v1 to get callback_lock.

Signed-off-by: Chen Ridong <chenridong@huawei.com>
---
 kernel/cgroup/cpuset-internal.h |  2 ++
 kernel/cgroup/cpuset.c          | 10 ++++++++++
 2 files changed, 12 insertions(+)

diff --git a/kernel/cgroup/cpuset-internal.h b/kernel/cgroup/cpuset-internal.h
index 02c4b0c74fa9..9a60dd6681e4 100644
--- a/kernel/cgroup/cpuset-internal.h
+++ b/kernel/cgroup/cpuset-internal.h
@@ -239,6 +239,8 @@ static inline int is_spread_slab(const struct cpuset *cs)
 }
 
 void rebuild_sched_domains_locked(void);
+void callback_lock_irq(void);
+void callback_unlock_irq(void);
 
 /*
  * cpuset-v1.c
diff --git a/kernel/cgroup/cpuset.c b/kernel/cgroup/cpuset.c
index 0a3347e4dddc..2b2dc963299b 100644
--- a/kernel/cgroup/cpuset.c
+++ b/kernel/cgroup/cpuset.c
@@ -269,6 +269,16 @@ void cpuset_unlock(void)
 
 static DEFINE_SPINLOCK(callback_lock);
 
+void callback_lock_irq(void)
+{
+	spin_lock_irq(&callback_lock);
+}
+
+void callback_unlock_irq(void)
+{
+	spin_unlock_irq(&callback_lock);
+}
+
 static struct workqueue_struct *cpuset_migrate_mm_wq;
 
 static DECLARE_WAIT_QUEUE_HEAD(cpuset_attach_wq);
-- 
2.34.1

[PATCH v2 -next 07/11] cgroup/cpuset: move legacy hotplug update to cpuset-v1.c

[Chen Ridong]

There are some differents about hotplug update between cpuset v1 and
cpuset v2. Move the legacy code to cpuset-v1.c.

'update_tasks_cpumask' and 'update_tasks_nodemask' are both used in cpuset
v1 and cpuset v2, declare them in cpuset-internal.h.

The change from original code is that use callback_lock helpers to get
callback_lock lock/unlock.

Signed-off-by: Chen Ridong <chenridong@huawei.com>
---
 kernel/cgroup/cpuset-internal.h |  5 ++
 kernel/cgroup/cpuset-v1.c       | 91 +++++++++++++++++++++++++++++++
 kernel/cgroup/cpuset.c          | 96 +--------------------------------
 3 files changed, 98 insertions(+), 94 deletions(-)

diff --git a/kernel/cgroup/cpuset-internal.h b/kernel/cgroup/cpuset-internal.h
index 9a60dd6681e4..7cd30ad809d5 100644
--- a/kernel/cgroup/cpuset-internal.h
+++ b/kernel/cgroup/cpuset-internal.h
@@ -241,6 +241,8 @@ static inline int is_spread_slab(const struct cpuset *cs)
 void rebuild_sched_domains_locked(void);
 void callback_lock_irq(void);
 void callback_unlock_irq(void);
+void update_tasks_cpumask(struct cpuset *cs, struct cpumask *new_cpus);
+void update_tasks_nodemask(struct cpuset *cs);
 
 /*
  * cpuset-v1.c
@@ -253,5 +255,8 @@ s64 cpuset_read_s64(struct cgroup_subsys_state *css, struct cftype *cft);
 void cpuset_update_task_spread_flags(struct cpuset *cs,
 					struct task_struct *tsk);
 void update_tasks_flags(struct cpuset *cs);
+void hotplug_update_tasks_legacy(struct cpuset *cs,
+			    struct cpumask *new_cpus, nodemask_t *new_mems,
+			    bool cpus_updated, bool mems_updated);
 
 #endif /* __CPUSET_INTERNAL_H */
diff --git a/kernel/cgroup/cpuset-v1.c b/kernel/cgroup/cpuset-v1.c
index 320abd4bf2c3..ce1d00746e92 100644
--- a/kernel/cgroup/cpuset-v1.c
+++ b/kernel/cgroup/cpuset-v1.c
@@ -2,6 +2,14 @@
 
 #include "cpuset-internal.h"
 
+/*
+ * Legacy hierarchy call to cgroup_transfer_tasks() is handled asynchrously
+ */
+struct cpuset_remove_tasks_struct {
+	struct work_struct work;
+	struct cpuset *cs;
+};
+
 /*
  * Frequency meter - How fast is some event occurring?
  *
@@ -237,3 +245,86 @@ void update_tasks_flags(struct cpuset *cs)
 	css_task_iter_end(&it);
 }
 
+/*
+ * 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 cpuset_migrate_tasks_workfn(struct work_struct *work)
+{
+	struct cpuset_remove_tasks_struct *s;
+
+	s = container_of(work, struct cpuset_remove_tasks_struct, work);
+	remove_tasks_in_empty_cpuset(s->cs);
+	css_put(&s->cs->css);
+	kfree(s);
+}
+
+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;
+
+	callback_lock_irq();
+	cpumask_copy(cs->cpus_allowed, new_cpus);
+	cpumask_copy(cs->effective_cpus, new_cpus);
+	cs->mems_allowed = *new_mems;
+	cs->effective_mems = *new_mems;
+	callback_unlock_irq();
+
+	/*
+	 * Don't call update_tasks_cpumask() if the cpuset becomes empty,
+	 * as the tasks will be migrated to an ancestor.
+	 */
+	if (cpus_updated && !cpumask_empty(cs->cpus_allowed))
+		update_tasks_cpumask(cs, new_cpus);
+	if (mems_updated && !nodes_empty(cs->mems_allowed))
+		update_tasks_nodemask(cs);
+
+	is_empty = cpumask_empty(cs->cpus_allowed) ||
+		   nodes_empty(cs->mems_allowed);
+
+	/*
+	 * Move tasks to the nearest ancestor with execution resources,
+	 * This is full cgroup operation which will also call back into
+	 * cpuset. Execute it asynchronously using workqueue.
+	 */
+	if (is_empty && cs->css.cgroup->nr_populated_csets &&
+	    css_tryget_online(&cs->css)) {
+		struct cpuset_remove_tasks_struct *s;
+
+		s = kzalloc(sizeof(*s), GFP_KERNEL);
+		if (WARN_ON_ONCE(!s)) {
+			css_put(&cs->css);
+			return;
+		}
+
+		s->cs = cs;
+		INIT_WORK(&s->work, cpuset_migrate_tasks_workfn);
+		schedule_work(&s->work);
+	}
+}
+
diff --git a/kernel/cgroup/cpuset.c b/kernel/cgroup/cpuset.c
index 2b2dc963299b..b93ef0b48eae 100644
--- a/kernel/cgroup/cpuset.c
+++ b/kernel/cgroup/cpuset.c
@@ -65,14 +65,6 @@ static const char * const perr_strings[] = {
 	[PERR_ACCESS]    = "Enable partition not permitted",
 };
 
-/*
- * Legacy hierarchy call to cgroup_transfer_tasks() is handled asynchrously
- */
-struct cpuset_remove_tasks_struct {
-	struct work_struct work;
-	struct cpuset *cs;
-};
-
 /*
  * Exclusive CPUs distributed out to sub-partitions of top_cpuset
  */
@@ -1138,7 +1130,7 @@ void rebuild_sched_domains(void)
  * is used instead of effective_cpus to make sure all offline CPUs are also
  * included as hotplug code won't update cpumasks for tasks in top_cpuset.
  */
-static void update_tasks_cpumask(struct cpuset *cs, struct cpumask *new_cpus)
+void update_tasks_cpumask(struct cpuset *cs, struct cpumask *new_cpus)
 {
 	struct css_task_iter it;
 	struct task_struct *task;
@@ -2591,7 +2583,7 @@ static void *cpuset_being_rebound;
  * effective cpuset's.  As this function is called with cpuset_mutex held,
  * cpuset membership stays stable.
  */
-static void update_tasks_nodemask(struct cpuset *cs)
+void update_tasks_nodemask(struct cpuset *cs)
 {
 	static nodemask_t newmems;	/* protected by cpuset_mutex */
 	struct css_task_iter it;
@@ -3923,90 +3915,6 @@ int __init cpuset_init(void)
 	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 cpuset_migrate_tasks_workfn(struct work_struct *work)
-{
-	struct cpuset_remove_tasks_struct *s;
-
-	s = container_of(work, struct cpuset_remove_tasks_struct, work);
-	remove_tasks_in_empty_cpuset(s->cs);
-	css_put(&s->cs->css);
-	kfree(s);
-}
-
-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 migrated to an ancestor.
-	 */
-	if (cpus_updated && !cpumask_empty(cs->cpus_allowed))
-		update_tasks_cpumask(cs, new_cpus);
-	if (mems_updated && !nodes_empty(cs->mems_allowed))
-		update_tasks_nodemask(cs);
-
-	is_empty = cpumask_empty(cs->cpus_allowed) ||
-		   nodes_empty(cs->mems_allowed);
-
-	/*
-	 * Move tasks to the nearest ancestor with execution resources,
-	 * This is full cgroup operation which will also call back into
-	 * cpuset. Execute it asynchronously using workqueue.
-	 */
-	if (is_empty && cs->css.cgroup->nr_populated_csets &&
-	    css_tryget_online(&cs->css)) {
-		struct cpuset_remove_tasks_struct *s;
-
-		s = kzalloc(sizeof(*s), GFP_KERNEL);
-		if (WARN_ON_ONCE(!s)) {
-			css_put(&cs->css);
-			return;
-		}
-
-		s->cs = cs;
-		INIT_WORK(&s->work, cpuset_migrate_tasks_workfn);
-		schedule_work(&s->work);
-	}
-}
-
 static void
 hotplug_update_tasks(struct cpuset *cs,
 		     struct cpumask *new_cpus, nodemask_t *new_mems,
-- 
2.34.1

[PATCH v2 -next 08/11] cgroup/cpuset: move validate_change_legacy to cpuset-v1.c

[Chen Ridong]

The validate_change_legacy functions is used for v1, move it to
cpuset-v1.c. And two micro 'cpuset_for_each_child' and
'cpuset_for_each_descendant_pre' are common for v1 and v2, move them to
cpuset-internal.h.

Signed-off-by: Chen Ridong <chenridong@huawei.com>
---
 kernel/cgroup/cpuset-internal.h | 29 +++++++++++++
 kernel/cgroup/cpuset-v1.c       | 45 ++++++++++++++++++++
 kernel/cgroup/cpuset.c          | 73 ---------------------------------
 3 files changed, 74 insertions(+), 73 deletions(-)

diff --git a/kernel/cgroup/cpuset-internal.h b/kernel/cgroup/cpuset-internal.h
index 7cd30ad809d5..07551ff0812e 100644
--- a/kernel/cgroup/cpuset-internal.h
+++ b/kernel/cgroup/cpuset-internal.h
@@ -238,6 +238,34 @@ static inline int is_spread_slab(const struct cpuset *cs)
 	return test_bit(CS_SPREAD_SLAB, &cs->flags);
 }
 
+/**
+ * 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)))))
+
 void rebuild_sched_domains_locked(void);
 void callback_lock_irq(void);
 void callback_unlock_irq(void);
@@ -258,5 +286,6 @@ void update_tasks_flags(struct cpuset *cs);
 void hotplug_update_tasks_legacy(struct cpuset *cs,
 			    struct cpumask *new_cpus, nodemask_t *new_mems,
 			    bool cpus_updated, bool mems_updated);
+int validate_change_legacy(struct cpuset *cur, struct cpuset *trial);
 
 #endif /* __CPUSET_INTERNAL_H */
diff --git a/kernel/cgroup/cpuset-v1.c b/kernel/cgroup/cpuset-v1.c
index ce1d00746e92..246fc962f549 100644
--- a/kernel/cgroup/cpuset-v1.c
+++ b/kernel/cgroup/cpuset-v1.c
@@ -328,3 +328,48 @@ void hotplug_update_tasks_legacy(struct cpuset *cs,
 	}
 }
 
+/*
+ * 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);
+}
+
+/*
+ * validate_change_legacy() - Validate conditions specific to legacy (v1)
+ *                            behavior.
+ */
+int validate_change_legacy(struct cpuset *cur, struct cpuset *trial)
+{
+	struct cgroup_subsys_state *css;
+	struct cpuset *c, *par;
+	int ret;
+
+	WARN_ON_ONCE(!rcu_read_lock_held());
+
+	/* 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;
+
+	/* On legacy hierarchy, we must be a subset of our parent cpuset. */
+	ret = -EACCES;
+	par = parent_cs(cur);
+	if (par && !is_cpuset_subset(trial, par))
+		goto out;
+
+	ret = 0;
+out:
+	return ret;
+}
+
diff --git a/kernel/cgroup/cpuset.c b/kernel/cgroup/cpuset.c
index b93ef0b48eae..4412a4168902 100644
--- a/kernel/cgroup/cpuset.c
+++ b/kernel/cgroup/cpuset.c
@@ -180,34 +180,6 @@ static struct cpuset top_cpuset = {
 	.remote_sibling = LIST_HEAD_INIT(top_cpuset.remote_sibling),
 };
 
-/**
- * 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
@@ -403,22 +375,6 @@ static void guarantee_online_mems(struct cpuset *cs, nodemask_t *pmask)
 	nodes_and(*pmask, cs->effective_mems, node_states[N_MEMORY]);
 }
 
-/*
- * 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_cpumasks - allocate three cpumasks for cpuset
  * @cs:  the cpuset that have cpumasks to be allocated.
@@ -549,35 +505,6 @@ static inline bool cpusets_are_exclusive(struct cpuset *cs1, struct cpuset *cs2)
 	return true;
 }
 
-/*
- * validate_change_legacy() - Validate conditions specific to legacy (v1)
- *                            behavior.
- */
-static int validate_change_legacy(struct cpuset *cur, struct cpuset *trial)
-{
-	struct cgroup_subsys_state *css;
-	struct cpuset *c, *par;
-	int ret;
-
-	WARN_ON_ONCE(!rcu_read_lock_held());
-
-	/* 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;
-
-	/* On legacy hierarchy, we must be a subset of our parent cpuset. */
-	ret = -EACCES;
-	par = parent_cs(cur);
-	if (par && !is_cpuset_subset(trial, par))
-		goto out;
-
-	ret = 0;
-out:
-	return ret;
-}
-
 /*
  * validate_change() - Used to validate that any proposed cpuset change
  *		       follows the structural rules for cpusets.
-- 
2.34.1

[PATCH v2 -next 09/11] cgroup/cpuset: move v1 interfaces to cpuset-v1.c

[Chen Ridong]

Move legacy cpuset controller interfaces files and corresponding code
into cpuset-v1.c. 'update_flag', 'cpuset_write_resmask' and
'cpuset_common_seq_show' are also used for v1, so declare them in
cpuset-internal.h.

'cpuset_write_s64', 'cpuset_read_s64' and 'fmeter_getrate' are only used
cpuset-v1.c now, make it static.

Signed-off-by: Chen Ridong <chenridong@huawei.com>
---
 kernel/cgroup/cpuset-internal.h |   9 +-
 kernel/cgroup/cpuset-v1.c       | 194 ++++++++++++++++++++++++++++++-
 kernel/cgroup/cpuset.c          | 195 +-------------------------------
 3 files changed, 199 insertions(+), 199 deletions(-)

diff --git a/kernel/cgroup/cpuset-internal.h b/kernel/cgroup/cpuset-internal.h
index 07551ff0812e..a6c71c86e58d 100644
--- a/kernel/cgroup/cpuset-internal.h
+++ b/kernel/cgroup/cpuset-internal.h
@@ -271,15 +271,16 @@ void callback_lock_irq(void);
 void callback_unlock_irq(void);
 void update_tasks_cpumask(struct cpuset *cs, struct cpumask *new_cpus);
 void update_tasks_nodemask(struct cpuset *cs);
+int update_flag(cpuset_flagbits_t bit, struct cpuset *cs, int turning_on);
+ssize_t cpuset_write_resmask(struct kernfs_open_file *of,
+				    char *buf, size_t nbytes, loff_t off);
+int cpuset_common_seq_show(struct seq_file *sf, void *v);
 
 /*
  * cpuset-v1.c
  */
+extern struct cftype legacy_files[];
 void fmeter_init(struct fmeter *fmp);
-int fmeter_getrate(struct fmeter *fmp);
-int cpuset_write_s64(struct cgroup_subsys_state *css, struct cftype *cft,
-			    s64 val);
-s64 cpuset_read_s64(struct cgroup_subsys_state *css, struct cftype *cft);
 void cpuset_update_task_spread_flags(struct cpuset *cs,
 					struct task_struct *tsk);
 void update_tasks_flags(struct cpuset *cs);
diff --git a/kernel/cgroup/cpuset-v1.c b/kernel/cgroup/cpuset-v1.c
index 246fc962f549..ffb8711cc8fa 100644
--- a/kernel/cgroup/cpuset-v1.c
+++ b/kernel/cgroup/cpuset-v1.c
@@ -100,7 +100,7 @@ static void fmeter_markevent(struct fmeter *fmp)
 }
 
 /* Process any previous ticks, then return current value. */
-int fmeter_getrate(struct fmeter *fmp)
+static int fmeter_getrate(struct fmeter *fmp)
 {
 	int val;
 
@@ -161,7 +161,7 @@ static int update_relax_domain_level(struct cpuset *cs, s64 val)
 	return 0;
 }
 
-int cpuset_write_s64(struct cgroup_subsys_state *css, struct cftype *cft,
+static int cpuset_write_s64(struct cgroup_subsys_state *css, struct cftype *cft,
 			    s64 val)
 {
 	struct cpuset *cs = css_cs(css);
@@ -187,7 +187,7 @@ int cpuset_write_s64(struct cgroup_subsys_state *css, struct cftype *cft,
 	return retval;
 }
 
-s64 cpuset_read_s64(struct cgroup_subsys_state *css, struct cftype *cft)
+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;
@@ -373,3 +373,191 @@ int validate_change_legacy(struct cpuset *cur, struct cpuset *trial)
 	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 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;
+
+	cpus_read_lock();
+	cpuset_lock();
+	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:
+	cpuset_unlock();
+	cpus_read_unlock();
+	return retval;
+}
+
+/*
+ * for the common functions, 'private' gives the type of file
+ */
+
+struct cftype legacy_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,
+		.private = FILE_MEMORY_PRESSURE,
+	},
+
+	{
+		.name = "memory_spread_page",
+		.read_u64 = cpuset_read_u64,
+		.write_u64 = cpuset_write_u64,
+		.private = FILE_SPREAD_PAGE,
+	},
+
+	{
+		/* obsolete, may be removed in the future */
+		.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 */
+};
+
diff --git a/kernel/cgroup/cpuset.c b/kernel/cgroup/cpuset.c
index 4412a4168902..2f52fe488f3a 100644
--- a/kernel/cgroup/cpuset.c
+++ b/kernel/cgroup/cpuset.c
@@ -1107,8 +1107,6 @@ enum partition_cmd {
 	partcmd_invalidate,	/* Make partition invalid	  */
 };
 
-static int update_flag(cpuset_flagbits_t bit, struct cpuset *cs,
-		       int turning_on);
 static void update_sibling_cpumasks(struct cpuset *parent, struct cpuset *cs,
 				    struct tmpmasks *tmp);
 
@@ -2703,7 +2701,7 @@ bool current_cpuset_is_being_rebound(void)
  * Call with cpuset_mutex held.
  */
 
-static int update_flag(cpuset_flagbits_t bit, struct cpuset *cs,
+int update_flag(cpuset_flagbits_t bit, struct cpuset *cs,
 		       int turning_on)
 {
 	struct cpuset *trialcs;
@@ -3088,59 +3086,10 @@ static void cpuset_attach(struct cgroup_taskset *tset)
 	mutex_unlock(&cpuset_mutex);
 }
 
-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;
-
-	cpus_read_lock();
-	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);
-	cpus_read_unlock();
-	return retval;
-}
-
 /*
  * Common handling for a write to a "cpus" or "mems" file.
  */
-static ssize_t cpuset_write_resmask(struct kernfs_open_file *of,
+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));
@@ -3215,7 +3164,7 @@ static ssize_t cpuset_write_resmask(struct kernfs_open_file *of,
  * 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)
+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;
@@ -3256,37 +3205,6 @@ static int cpuset_common_seq_show(struct seq_file *sf, void *v)
 	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 int sched_partition_show(struct seq_file *seq, void *v)
 {
 	struct cpuset *cs = css_cs(seq_css(seq));
@@ -3350,113 +3268,6 @@ static ssize_t sched_partition_write(struct kernfs_open_file *of, char *buf,
 	return retval ?: nbytes;
 }
 
-/*
- * for the common functions, 'private' gives the type of file
- */
-
-static struct cftype legacy_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,
-		.private = FILE_MEMORY_PRESSURE,
-	},
-
-	{
-		.name = "memory_spread_page",
-		.read_u64 = cpuset_read_u64,
-		.write_u64 = cpuset_write_u64,
-		.private = FILE_SPREAD_PAGE,
-	},
-
-	{
-		/* obsolete, may be removed in the future */
-		.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 */
-};
-
 /*
  * This is currently a minimal set for the default hierarchy. It can be
  * expanded later on by migrating more features and control files from v1.
-- 
2.34.1

[PATCH v2 -next 10/11] cgroup/cpuset: guard cpuset-v1 code under CONFIG_CPUSETS_V1

[Chen Ridong]

This patch introduces CONFIG_CPUSETS_V1 and guard cpuset-v1 code under
CONFIG_CPUSETS_V1. The default value of CONFIG_CPUSETS_V1 is N, so that
user who adopted v2 don't have 'pay' for cpuset v1.

Signed-off-by: Chen Ridong <chenridong@huawei.com>
---
 include/linux/cpuset.h          |  4 ++++
 init/Kconfig                    | 13 +++++++++++++
 kernel/cgroup/Makefile          |  3 ++-
 kernel/cgroup/cpuset-internal.h | 13 +++++++++++++
 kernel/cgroup/cpuset.c          |  2 ++
 5 files changed, 34 insertions(+), 1 deletion(-)

diff --git a/include/linux/cpuset.h b/include/linux/cpuset.h
index 2a6981eeebf8..835e7b793f6a 100644
--- a/include/linux/cpuset.h
+++ b/include/linux/cpuset.h
@@ -99,6 +99,7 @@ static inline bool cpuset_zone_allowed(struct zone *z, gfp_t gfp_mask)
 extern int cpuset_mems_allowed_intersects(const struct task_struct *tsk1,
 					  const struct task_struct *tsk2);
 
+#ifdef CONFIG_CPUSETS_V1
 #define cpuset_memory_pressure_bump() 				\
 	do {							\
 		if (cpuset_memory_pressure_enabled)		\
@@ -106,6 +107,9 @@ extern int cpuset_mems_allowed_intersects(const struct task_struct *tsk1,
 	} while (0)
 extern int cpuset_memory_pressure_enabled;
 extern void __cpuset_memory_pressure_bump(void);
+#else
+static inline void cpuset_memory_pressure_bump(void) { }
+#endif
 
 extern void cpuset_task_status_allowed(struct seq_file *m,
 					struct task_struct *task);
diff --git a/init/Kconfig b/init/Kconfig
index a465ea9525bd..8bf091354bea 100644
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -1143,6 +1143,19 @@ config CPUSETS
 
 	  Say N if unsure.
 
+config CPUSETS_V1
+	bool "Legacy cgroup v1 cpusets controller"
+	depends on CPUSETS
+	default n
+	help
+	  Legacy cgroup v1 cpusets controller which has been deprecated by
+	  cgroup v2 implementation. The v1 is there for legacy applications
+	  which haven't migrated to the new cgroup v2 interface yet. If you
+	  do not have any such application then you are completely fine leaving
+	  this option disabled.
+
+	  Say N if unsure.
+
 config PROC_PID_CPUSET
 	bool "Include legacy /proc/<pid>/cpuset file"
 	depends on CPUSETS
diff --git a/kernel/cgroup/Makefile b/kernel/cgroup/Makefile
index 005ac4c675cb..a5c9359d516f 100644
--- a/kernel/cgroup/Makefile
+++ b/kernel/cgroup/Makefile
@@ -4,6 +4,7 @@ obj-y := cgroup.o rstat.o namespace.o cgroup-v1.o freezer.o
 obj-$(CONFIG_CGROUP_FREEZER) += legacy_freezer.o
 obj-$(CONFIG_CGROUP_PIDS) += pids.o
 obj-$(CONFIG_CGROUP_RDMA) += rdma.o
-obj-$(CONFIG_CPUSETS) += cpuset.o cpuset-v1.o
+obj-$(CONFIG_CPUSETS) += cpuset.o
+obj-$(CONFIG_CPUSETS_V1) += cpuset-v1.o
 obj-$(CONFIG_CGROUP_MISC) += misc.o
 obj-$(CONFIG_CGROUP_DEBUG) += debug.o
diff --git a/kernel/cgroup/cpuset-internal.h b/kernel/cgroup/cpuset-internal.h
index a6c71c86e58d..7ec702dff877 100644
--- a/kernel/cgroup/cpuset-internal.h
+++ b/kernel/cgroup/cpuset-internal.h
@@ -279,6 +279,7 @@ int cpuset_common_seq_show(struct seq_file *sf, void *v);
 /*
  * cpuset-v1.c
  */
+#ifdef CONFIG_CPUSETS_V1
 extern struct cftype legacy_files[];
 void fmeter_init(struct fmeter *fmp);
 void cpuset_update_task_spread_flags(struct cpuset *cs,
@@ -289,4 +290,16 @@ void hotplug_update_tasks_legacy(struct cpuset *cs,
 			    bool cpus_updated, bool mems_updated);
 int validate_change_legacy(struct cpuset *cur, struct cpuset *trial);
 
+#else
+static inline void fmeter_init(struct fmeter *fmp) {}
+static inline void cpuset_update_task_spread_flags(struct cpuset *cs,
+					struct task_struct *tsk) {}
+static inline void update_tasks_flags(struct cpuset *cs) {}
+static inline void hotplug_update_tasks_legacy(struct cpuset *cs,
+			    struct cpumask *new_cpus, nodemask_t *new_mems,
+			    bool cpus_updated, bool mems_updated) {}
+static inline int validate_change_legacy(struct cpuset *cur,
+				struct cpuset *trial) { return 0; }
+
+#endif /* CONFIG_CPUSETS_V1 */
 #endif /* __CPUSET_INTERNAL_H */
diff --git a/kernel/cgroup/cpuset.c b/kernel/cgroup/cpuset.c
index 2f52fe488f3a..2cefeaaff742 100644
--- a/kernel/cgroup/cpuset.c
+++ b/kernel/cgroup/cpuset.c
@@ -3617,7 +3617,9 @@ struct cgroup_subsys cpuset_cgrp_subsys = {
 	.can_fork	= cpuset_can_fork,
 	.cancel_fork	= cpuset_cancel_fork,
 	.fork		= cpuset_fork,
+#ifdef CONFIG_CPUSETS_V1
 	.legacy_cftypes	= legacy_files,
+#endif
 	.dfl_cftypes	= dfl_files,
 	.early_init	= true,
 	.threaded	= true,
-- 
2.34.1

[PATCH v2 -next 11/11] cgroup/cpuset: add sefltest for cpuset v1

[Chen Ridong]

There is only hotplug test for cpuset v1, just add base read/write test
for cpuset v1.

Signed-off-by: Chen Ridong <chenridong@huawei.com>
---
 MAINTAINERS                                   |  1 +
 .../selftests/cgroup/test_cpuset_v1_base.sh   | 77 +++++++++++++++++++
 2 files changed, 78 insertions(+)
 create mode 100755 tools/testing/selftests/cgroup/test_cpuset_v1_base.sh

diff --git a/MAINTAINERS b/MAINTAINERS
index 3b5ec1cafd95..b59f54e1e30d 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -5703,6 +5703,7 @@ F:	kernel/cgroup/cpuset-v1.c
 F:	kernel/cgroup/cpuset.c
 F:	tools/testing/selftests/cgroup/test_cpuset.c
 F:	tools/testing/selftests/cgroup/test_cpuset_prs.sh
+F:	tools/testing/selftests/cgroup/test_cpuset_v1_base.sh
 
 CONTROL GROUP - MEMORY RESOURCE CONTROLLER (MEMCG)
 M:	Johannes Weiner <hannes@cmpxchg.org>
diff --git a/tools/testing/selftests/cgroup/test_cpuset_v1_base.sh b/tools/testing/selftests/cgroup/test_cpuset_v1_base.sh
new file mode 100755
index 000000000000..42a6628fb8bc
--- /dev/null
+++ b/tools/testing/selftests/cgroup/test_cpuset_v1_base.sh
@@ -0,0 +1,77 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+#
+# Basc test for cpuset v1 interfaces write/read
+#
+
+skip_test() {
+	echo "$1"
+	echo "Test SKIPPED"
+	exit 4 # ksft_skip
+}
+
+write_test() {
+	dir=$1
+	interface=$2
+	value=$3
+	original=$(cat $dir/$interface)
+	echo "testing $interface $value"
+	echo $value > $dir/$interface
+	new=$(cat $dir/$interface)
+	[[ $value -ne $(cat $dir/$interface) ]] && {
+		echo "$interface write $value failed: new:$new"
+		exit 1
+	}
+}
+
+[[ $(id -u) -eq 0 ]] || skip_test "Test must be run as root!"
+
+# Find cpuset v1 mount point
+CPUSET=$(mount -t cgroup | grep cpuset | head -1 | awk '{print $3}')
+[[ -n "$CPUSET" ]] || skip_test "cpuset v1 mount point not found!"
+
+#
+# Create a test cpuset, read write test
+#
+TDIR=test$$
+[[ -d $CPUSET/$TDIR ]] || mkdir $CPUSET/$TDIR
+
+ITF_MATRIX=(
+	#interface			value		expect 	root_only
+	'cpuset.cpus			0-1		0-1	0'
+	'cpuset.mem_exclusive		1		1	0'
+	'cpuset.mem_exclusive		0		0	0'
+	'cpuset.mem_hardwall		1		1	0'
+	'cpuset.mem_hardwall		0		0	0'
+	'cpuset.memory_migrate		1		1	0'
+	'cpuset.memory_migrate		0		0	0'
+	'cpuset.memory_spread_page	1		1	0'
+	'cpuset.memory_spread_page	0		0	0'
+	'cpuset.memory_spread_slab	1		1	0'
+	'cpuset.memory_spread_slab	0		0	0'
+	'cpuset.mems			0		0	0'
+	'cpuset.sched_load_balance	1		1	0'
+	'cpuset.sched_load_balance	0		0	0'
+	'cpuset.sched_relax_domain_level	2	2	0'
+	'cpuset.memory_pressure_enabled	1		1	1'
+	'cpuset.memory_pressure_enabled	0		0	1'
+)
+
+run_test()
+{
+	cnt="${ITF_MATRIX[@]}"
+	for i in "${ITF_MATRIX[@]}" ; do
+		args=($i)
+		root_only=${args[3]}
+		[[ $root_only -eq 1 ]] && {
+			write_test "$CPUSET" "${args[0]}" "${args[1]}" "${args[2]}"
+			continue
+		}
+		write_test "$CPUSET/$TDIR" "${args[0]}" "${args[1]}" "${args[2]}"
+	done
+}
+
+run_test
+rmdir $CPUSET/$TDIR
+echo "Test PASSED"
+exit 0
-- 
2.34.1

Re: [PATCH v2 -next 01/11] cgroup/cpuset: introduce cpuset-v1.c

[Waiman Long]

On 8/26/24 09:26, Chen Ridong wrote:
> This patch introduces the cgroup/cpuset-v1.c source file which will be
> used for all legacy (cgroup v1) cpuset cgroup code. It also introduces
> cgroup/cpuset-internal.h to keep declarations shared between
> cgroup/cpuset.c and cpuset/cpuset-v1.c.
>
> As of now, let's compile it if CONFIG_CPUSET is set. Later on it can be
> switched to use a separate config option, so that the legacy code won't be
> compiled if not required.
>
> Signed-off-by: Chen Ridong <chenridong@huawei.com>
> ---
>   MAINTAINERS                     | 2 ++
>   kernel/cgroup/Makefile          | 2 +-
>   kernel/cgroup/cpuset-internal.h | 7 +++++++
>   kernel/cgroup/cpuset-v1.c       | 4 ++++
>   4 files changed, 14 insertions(+), 1 deletion(-)
>   create mode 100644 kernel/cgroup/cpuset-internal.h
>   create mode 100644 kernel/cgroup/cpuset-v1.c
>
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 82e3924816d2..3b5ec1cafd95 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -5698,6 +5698,8 @@ S:	Maintained
>   T:	git git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup.git
>   F:	Documentation/admin-guide/cgroup-v1/cpusets.rst
>   F:	include/linux/cpuset.h
> +F:	kernel/cgroup/cpuset-internal.h
> +F:	kernel/cgroup/cpuset-v1.c
>   F:	kernel/cgroup/cpuset.c
>   F:	tools/testing/selftests/cgroup/test_cpuset.c
>   F:	tools/testing/selftests/cgroup/test_cpuset_prs.sh
> diff --git a/kernel/cgroup/Makefile b/kernel/cgroup/Makefile
> index 12f8457ad1f9..005ac4c675cb 100644
> --- a/kernel/cgroup/Makefile
> +++ b/kernel/cgroup/Makefile
> @@ -4,6 +4,6 @@ obj-y := cgroup.o rstat.o namespace.o cgroup-v1.o freezer.o
>   obj-$(CONFIG_CGROUP_FREEZER) += legacy_freezer.o
>   obj-$(CONFIG_CGROUP_PIDS) += pids.o
>   obj-$(CONFIG_CGROUP_RDMA) += rdma.o
> -obj-$(CONFIG_CPUSETS) += cpuset.o
> +obj-$(CONFIG_CPUSETS) += cpuset.o cpuset-v1.o
>   obj-$(CONFIG_CGROUP_MISC) += misc.o
>   obj-$(CONFIG_CGROUP_DEBUG) += debug.o
> diff --git a/kernel/cgroup/cpuset-internal.h b/kernel/cgroup/cpuset-internal.h
> new file mode 100644
> index 000000000000..6605be417e32
> --- /dev/null
> +++ b/kernel/cgroup/cpuset-internal.h
> @@ -0,0 +1,7 @@
> +/* SPDX-License-Identifier: GPL-2.0-or-later */
> +
> +#ifndef __CPUSET_INTERNAL_H
> +#define __CPUSET_INTERNAL_H
> +
> +#endif /* __CPUSET_INTERNAL_H */
> +
> diff --git a/kernel/cgroup/cpuset-v1.c b/kernel/cgroup/cpuset-v1.c
> new file mode 100644
> index 000000000000..ae166eb4f75d
> --- /dev/null
> +++ b/kernel/cgroup/cpuset-v1.c
> @@ -0,0 +1,4 @@
> +// SPDX-License-Identifier: GPL-2.0-or-later
> +
> +#include "cpuset-internal.h"
> +

Don't leave a blank line at the end of a file. You will get the 
following error when applying the patch.

0001-cgroup_cpuset-introduce-cpuset-v1.c.patch:70: new blank line at EOF.

All your patches except the last one have this problem.

Cheers,
Longman

Re: [PATCH v2 -next 09/11] cgroup/cpuset: move v1 interfaces to cpuset-v1.c

[Waiman Long]

On 8/26/24 09:27, Chen Ridong wrote:
> Move legacy cpuset controller interfaces files and corresponding code
> into cpuset-v1.c. 'update_flag', 'cpuset_write_resmask' and
> 'cpuset_common_seq_show' are also used for v1, so declare them in
> cpuset-internal.h.
>
> 'cpuset_write_s64', 'cpuset_read_s64' and 'fmeter_getrate' are only used
> cpuset-v1.c now, make it static.
>
> Signed-off-by: Chen Ridong <chenridong@huawei.com>
> ---
>   kernel/cgroup/cpuset-internal.h |   9 +-
>   kernel/cgroup/cpuset-v1.c       | 194 ++++++++++++++++++++++++++++++-
>   kernel/cgroup/cpuset.c          | 195 +-------------------------------
>   3 files changed, 199 insertions(+), 199 deletions(-)
>
> diff --git a/kernel/cgroup/cpuset-internal.h b/kernel/cgroup/cpuset-internal.h
> index 07551ff0812e..a6c71c86e58d 100644
> --- a/kernel/cgroup/cpuset-internal.h
> +++ b/kernel/cgroup/cpuset-internal.h
> @@ -271,15 +271,16 @@ void callback_lock_irq(void);
>   void callback_unlock_irq(void);
>   void update_tasks_cpumask(struct cpuset *cs, struct cpumask *new_cpus);
>   void update_tasks_nodemask(struct cpuset *cs);
> +int update_flag(cpuset_flagbits_t bit, struct cpuset *cs, int turning_on);
> +ssize_t cpuset_write_resmask(struct kernfs_open_file *of,
> +				    char *buf, size_t nbytes, loff_t off);
> +int cpuset_common_seq_show(struct seq_file *sf, void *v);
>   
>   /*
>    * cpuset-v1.c
>    */
> +extern struct cftype legacy_files[];

The legacy_files name is rather generic. By making it globally visible 
within the kernel, it runs the risk conflicting with another variable of 
the same name (namespace pollution). I would suggest adding "cpuset_" 
prefix to make it unique to cpuset.

The following functions also have similar issue.

- update_flag()
- update_tasks_flags()
- validate_change_legacy()
- callback_lock_irq()
- callback_unlock_irq().

Another alternative is to include cpuset-v1.c directly into cpuset.c like

#ifdef CONFIG_CPUSETS_V1
#include "cpuset-v1.c"
#else
    ....
#endif

Then you don't need to change the names and will not need 
cpuset-internal.h. It is up to you to decide what you want to do.

Cheers,
Longman

Re: [PATCH v2 -next 09/11] cgroup/cpuset: move v1 interfaces to cpuset-v1.c

[Tejun Heo]

On Mon, Aug 26, 2024 at 03:30:14PM -0400, Waiman Long wrote:
...
> Another alternative is to include cpuset-v1.c directly into cpuset.c like
> 
> #ifdef CONFIG_CPUSETS_V1
> #include "cpuset-v1.c"
> #else
>    ....
> #endif
> 
> Then you don't need to change the names and will not need cpuset-internal.h.
> It is up to you to decide what you want to do.

FWIW, I'd prefer to have cpuset1_ prefixed functions declared in cpuset1.h
or something rather than including .c file.

Thanks.

-- 
tejun

Re: [PATCH v2 -next 09/11] cgroup/cpuset: move v1 interfaces to cpuset-v1.c

[Waiman Long]

On 8/26/24 15:40, Tejun Heo wrote:
> On Mon, Aug 26, 2024 at 03:30:14PM -0400, Waiman Long wrote:
> ...
>> Another alternative is to include cpuset-v1.c directly into cpuset.c like
>>
>> #ifdef CONFIG_CPUSETS_V1
>> #include "cpuset-v1.c"
>> #else
>>     ....
>> #endif
>>
>> Then you don't need to change the names and will not need cpuset-internal.h.
>> It is up to you to decide what you want to do.
> FWIW, I'd prefer to have cpuset1_ prefixed functions declared in cpuset1.h
> or something rather than including .c file.

Sure. Let's have "cpuset1_" prefix if it is v1 specific and "cpuset_" 
prefix if it is used by both v1 and v2. That applies only to newly 
exposed names.

Cheers,
Longman

Re: [PATCH v2 -next 01/11] cgroup/cpuset: introduce cpuset-v1.c

[Chen Ridong]

On 2024/8/27 3:07, Waiman Long wrote:
> On 8/26/24 09:26, Chen Ridong wrote:
>> This patch introduces the cgroup/cpuset-v1.c source file which will be
>> used for all legacy (cgroup v1) cpuset cgroup code. It also introduces
>> cgroup/cpuset-internal.h to keep declarations shared between
>> cgroup/cpuset.c and cpuset/cpuset-v1.c.
>>
>> As of now, let's compile it if CONFIG_CPUSET is set. Later on it can be
>> switched to use a separate config option, so that the legacy code 
>> won't be
>> compiled if not required.
>>
>> Signed-off-by: Chen Ridong <chenridong@huawei.com>
>> ---
>>   MAINTAINERS                     | 2 ++
>>   kernel/cgroup/Makefile          | 2 +-
>>   kernel/cgroup/cpuset-internal.h | 7 +++++++
>>   kernel/cgroup/cpuset-v1.c       | 4 ++++
>>   4 files changed, 14 insertions(+), 1 deletion(-)
>>   create mode 100644 kernel/cgroup/cpuset-internal.h
>>   create mode 100644 kernel/cgroup/cpuset-v1.c
>>
>> diff --git a/MAINTAINERS b/MAINTAINERS
>> index 82e3924816d2..3b5ec1cafd95 100644
>> --- a/MAINTAINERS
>> +++ b/MAINTAINERS
>> @@ -5698,6 +5698,8 @@ S:    Maintained
>>   T:    git git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup.git
>>   F:    Documentation/admin-guide/cgroup-v1/cpusets.rst
>>   F:    include/linux/cpuset.h
>> +F:    kernel/cgroup/cpuset-internal.h
>> +F:    kernel/cgroup/cpuset-v1.c
>>   F:    kernel/cgroup/cpuset.c
>>   F:    tools/testing/selftests/cgroup/test_cpuset.c
>>   F:    tools/testing/selftests/cgroup/test_cpuset_prs.sh
>> diff --git a/kernel/cgroup/Makefile b/kernel/cgroup/Makefile
>> index 12f8457ad1f9..005ac4c675cb 100644
>> --- a/kernel/cgroup/Makefile
>> +++ b/kernel/cgroup/Makefile
>> @@ -4,6 +4,6 @@ obj-y := cgroup.o rstat.o namespace.o cgroup-v1.o 
>> freezer.o
>>   obj-$(CONFIG_CGROUP_FREEZER) += legacy_freezer.o
>>   obj-$(CONFIG_CGROUP_PIDS) += pids.o
>>   obj-$(CONFIG_CGROUP_RDMA) += rdma.o
>> -obj-$(CONFIG_CPUSETS) += cpuset.o
>> +obj-$(CONFIG_CPUSETS) += cpuset.o cpuset-v1.o
>>   obj-$(CONFIG_CGROUP_MISC) += misc.o
>>   obj-$(CONFIG_CGROUP_DEBUG) += debug.o
>> diff --git a/kernel/cgroup/cpuset-internal.h 
>> b/kernel/cgroup/cpuset-internal.h
>> new file mode 100644
>> index 000000000000..6605be417e32
>> --- /dev/null
>> +++ b/kernel/cgroup/cpuset-internal.h
>> @@ -0,0 +1,7 @@
>> +/* SPDX-License-Identifier: GPL-2.0-or-later */
>> +
>> +#ifndef __CPUSET_INTERNAL_H
>> +#define __CPUSET_INTERNAL_H
>> +
>> +#endif /* __CPUSET_INTERNAL_H */
>> +
>> diff --git a/kernel/cgroup/cpuset-v1.c b/kernel/cgroup/cpuset-v1.c
>> new file mode 100644
>> index 000000000000..ae166eb4f75d
>> --- /dev/null
>> +++ b/kernel/cgroup/cpuset-v1.c
>> @@ -0,0 +1,4 @@
>> +// SPDX-License-Identifier: GPL-2.0-or-later
>> +
>> +#include "cpuset-internal.h"
>> +
> 
> Don't leave a blank line at the end of a file. You will get the 
> following error when applying the patch.
> 
> 0001-cgroup_cpuset-introduce-cpuset-v1.c.patch:70: new blank line at EOF.
> 
> All your patches except the last one have this problem.
> 
> Cheers,
> Longman

Thank you, will fix it.

Best regards,
Ridong

Re: [PATCH v2 -next 09/11] cgroup/cpuset: move v1 interfaces to cpuset-v1.c

[chenridong]

On 2024/8/27 3:47, Waiman Long wrote:
> 
> On 8/26/24 15:40, Tejun Heo wrote:
>> On Mon, Aug 26, 2024 at 03:30:14PM -0400, Waiman Long wrote:
>> ...
>>> Another alternative is to include cpuset-v1.c directly into cpuset.c 
>>> like
>>>
>>> #ifdef CONFIG_CPUSETS_V1
>>> #include "cpuset-v1.c"
>>> #else
>>>     ....
>>> #endif
>>>
>>> Then you don't need to change the names and will not need 
>>> cpuset-internal.h.
>>> It is up to you to decide what you want to do.
>> FWIW, I'd prefer to have cpuset1_ prefixed functions declared in 
>> cpuset1.h
>> or something rather than including .c file.
> 
> Sure. Let's have "cpuset1_" prefix if it is v1 specific and "cpuset_" 
> prefix if it is used by both v1 and v2. That applies only to newly 
> exposed names.
> 
> Cheers,
> Longman
> 
I will rename the functions with cpuset1_/cpuset_ prefix.

Thanks,
Ridong