Commit 94dc216a authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge tag 'cgroup-for-6.15' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup 

Pull cgroup updates from Tejun Heo:

 - Add deprecation info messages to cgroup1-only features

 - rstat updates including a bug fix and breaking up a critical section
   to reduce interrupt latency impact

 - Other misc and doc updates

* tag 'cgroup-for-6.15' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
  cgroup: rstat: Cleanup flushing functions and locking
  cgroup/rstat: avoid disabling irqs for O(num_cpu)
  mm: Fix a build breakage in memcontrol-v1.c
  blk-cgroup: Simplify policy files registration
  cgroup: Update file naming comment
  cgroup: Add deprecation message to legacy freezer controller
  mm: Add transformation message for per-memcg swappiness
  RFC cgroup/cpuset-v1: Add deprecation messages to sched_relax_domain_level
  cgroup/cpuset-v1: Add deprecation messages to memory_migrate
  cgroup/cpuset-v1: Add deprecation messages to mem_exclusive and mem_hardwall
  cgroup: Print message when /proc/cgroups is read on v2-only system
  cgroup/blkio: Add deprecation messages to reset_stats
  cgroup/cpuset-v1: Add deprecation messages to memory_spread_page and memory_spread_slab
  cgroup/cpuset-v1: Add deprecation messages to sched_load_balance and memory_pressure_enabled
  cgroup, docs: Be explicit about independence of RT_GROUP_SCHED and non-cpu controllers
  cgroup/rstat: Fix forceidle time in cpu.stat
  cgroup/misc: Remove unused misc_cg_res_total_usage
  cgroup/cpuset: Move procfs cpuset attribute under cgroup-v1.c
  cgroup: update comment about dropping cgroup kn refs
parents b05f8fbe 093c8812

Documentation/admin-guide/cgroup-v1/freezer-subsystem.rst

+4 −0
Original line number Diff line number Diff line
@@ -125,3 +125,7 @@ to unfreeze all tasks in the container:: 


This is the basic mechanism which should do the right thing for user space task

in a simple scenario.



This freezer implementation is affected by shortcomings (see commit

76f969e8948d8 ("cgroup: cgroup v2 freezer")) and cgroup v2 freezer is

recommended.

Documentation/admin-guide/cgroup-v1/memory.rst

+1 −0
Original line number Diff line number Diff line
@@ -90,6 +90,7 @@ Brief summary of control files. 
                                     used.

 memory.swappiness		     set/show swappiness parameter of vmscan

				     (See sysctl's vm.swappiness)

				     Per memcg knob does not exist in cgroup v2.

 memory.move_charge_at_immigrate     This knob is deprecated.

 memory.oom_control		     set/show oom controls.

                                     This knob is deprecated and shouldn't be

Documentation/admin-guide/cgroup-v2.rst

+14 −9
Original line number Diff line number Diff line
@@ -1076,15 +1076,20 @@ cpufreq governor about the minimum desired frequency which should always be 
provided by a CPU, as well as the maximum desired frequency, which should not

be exceeded by a CPU.



WARNING: cgroup2 doesn't yet support control of realtime processes. For

a kernel built with the CONFIG_RT_GROUP_SCHED option enabled for group

scheduling of realtime processes, the cpu controller can only be enabled

when all RT processes are in the root cgroup.  This limitation does

not apply if CONFIG_RT_GROUP_SCHED is disabled.  Be aware that system

management software may already have placed RT processes into nonroot

cgroups during the system boot process, and these processes may need

to be moved to the root cgroup before the cpu controller can be enabled

with a CONFIG_RT_GROUP_SCHED enabled kernel.

WARNING: cgroup2 cpu controller doesn't yet fully support the control of

realtime processes. For a kernel built with the CONFIG_RT_GROUP_SCHED option

enabled for group scheduling of realtime processes, the cpu controller can only

be enabled when all RT processes are in the root cgroup. Be aware that system

management software may already have placed RT processes into non-root cgroups

during the system boot process, and these processes may need to be moved to the

root cgroup before the cpu controller can be enabled with a

CONFIG_RT_GROUP_SCHED enabled kernel.



With CONFIG_RT_GROUP_SCHED disabled, this limitation does not apply and some of

the interface files either affect realtime processes or account for them. See

the following section for details. Only the cpu controller is affected by

CONFIG_RT_GROUP_SCHED. Other controllers can be used for the resource control of

realtime processes irrespective of CONFIG_RT_GROUP_SCHED.





CPU Interface Files

block/blk-cgroup.c

+6 −2
Original line number Diff line number Diff line
@@ -659,6 +659,7 @@ static int blkcg_reset_stats(struct cgroup_subsys_state *css, 
	struct blkcg_gq *blkg;

	int i;



	pr_info_once("blkio.%s is deprecated\n", cftype->name);

	mutex_lock(&blkcg_pol_mutex);

	spin_lock_irq(&blkcg->lock);
@@ -1770,12 +1771,15 @@ int blkcg_policy_register(struct blkcg_policy *pol) 
	mutex_unlock(&blkcg_pol_mutex);



	/* everything is in place, add intf files for the new policy */

	if (pol->dfl_cftypes)

	if (pol->dfl_cftypes == pol->legacy_cftypes) {

		WARN_ON(cgroup_add_cftypes(&io_cgrp_subsys,

					   pol->dfl_cftypes));

	} else {

		WARN_ON(cgroup_add_dfl_cftypes(&io_cgrp_subsys,

					       pol->dfl_cftypes));

	if (pol->legacy_cftypes)

		WARN_ON(cgroup_add_legacy_cftypes(&io_cgrp_subsys,

						  pol->legacy_cftypes));

	}

	mutex_unlock(&blkcg_pol_register_mutex);

	return 0;

block/blk-ioprio.c

+7 −16
Original line number Diff line number Diff line
@@ -113,27 +113,18 @@ static void ioprio_free_cpd(struct blkcg_policy_data *cpd) 
	kfree(blkcg);

}



#define IOPRIO_ATTRS						\

	{							\

		.name		= "prio.class",			\

		.seq_show	= ioprio_show_prio_policy,	\

		.write		= ioprio_set_prio_policy,	\

	},							\

	{ } /* sentinel */



/* cgroup v2 attributes */

static struct cftype ioprio_files[] = {

	IOPRIO_ATTRS

};



/* cgroup v1 attributes */

static struct cftype ioprio_legacy_files[] = {

	IOPRIO_ATTRS

	{

		.name		= "prio.class",

		.seq_show	= ioprio_show_prio_policy,

		.write		= ioprio_set_prio_policy,

	},

	{ } /* sentinel */

};



static struct blkcg_policy ioprio_policy = {

	.dfl_cftypes	= ioprio_files,

	.legacy_cftypes = ioprio_legacy_files,

	.legacy_cftypes = ioprio_files,



	.cpd_alloc_fn	= ioprio_alloc_cpd,

	.cpd_free_fn	= ioprio_free_cpd,