!4582 cgroup/hugetlb: hugetlb accounting (d68969ba) · Commits · EulixOS / Software / Kernel

Documentation/admin-guide/cgroup-v2.rst

+29 −0

Original line number	Diff line number	Diff line
		@@ -210,6 +210,35 @@ cgroup v2 currently supports the following mount options.
		relying on the original semantics (e.g. specifying bogusly
		high 'bypass' protection values at higher tree levels).

		memory_hugetlb_accounting
		Count HugeTLB memory usage towards the cgroup's overall
		memory usage for the memory controller (for the purpose of
		statistics reporting and memory protetion). This is a new
		behavior that could regress existing setups, so it must be
		explicitly opted in with this mount option.

		A few caveats to keep in mind:

		* There is no HugeTLB pool management involved in the memory
		controller. The pre-allocated pool does not belong to anyone.
		Specifically, when a new HugeTLB folio is allocated to
		the pool, it is not accounted for from the perspective of the
		memory controller. It is only charged to a cgroup when it is
		actually used (for e.g at page fault time). Host memory
		overcommit management has to consider this when configuring
		hard limits. In general, HugeTLB pool management should be
		done via other mechanisms (such as the HugeTLB controller).
		* Failure to charge a HugeTLB folio to the memory controller
		results in SIGBUS. This could happen even if the HugeTLB pool
		still has pages available (but the cgroup limit is hit and
		reclaim attempt fails).
		* Charging HugeTLB memory towards the memory controller affects
		memory protection and reclaim dynamics. Any userspace tuning
		(of low, min limits for e.g) needs to take this into account.
		* HugeTLB pages utilized while this option is not selected
		will not be tracked by the memory controller (even if cgroup
		v2 is remounted later on).


		Organizing Processes and Threads
		--------------------------------

include/linux/cgroup-defs.h

+5 −0

Original line number	Diff line number	Diff line
		@@ -116,6 +116,11 @@ enum {
		* Enable recursive subtree protection
		*/
		CGRP_ROOT_MEMORY_RECURSIVE_PROT = (1 << 18),

		/*
		* Enable hugetlb accounting for the memory controller.
		*/
		CGRP_ROOT_MEMORY_HUGETLB_ACCOUNTING = (1 << 19),
		};

		/* cftype->flags */

include/linux/memcontrol.h

+37 −0

Original line number	Diff line number	Diff line
		@@ -781,6 +781,8 @@ static inline bool mem_cgroup_below_min(struct mem_cgroup *target,
		page_counter_read(&memcg->memory);
		}

		void mem_cgroup_commit_charge(struct folio folio, struct mem_cgroup memcg);

		int __mem_cgroup_charge(struct folio folio, struct mm_struct mm, gfp_t gfp);

		/**
		@@ -805,6 +807,9 @@ static inline int mem_cgroup_charge(struct folio folio, struct mm_struct mm,
		return __mem_cgroup_charge(folio, mm, gfp);
		}

		int mem_cgroup_hugetlb_try_charge(struct mem_cgroup *memcg, gfp_t gfp,
		long nr_pages);

		int mem_cgroup_swapin_charge_folio(struct folio folio, struct mm_struct mm,
		gfp_t gfp, swp_entry_t entry);
		void mem_cgroup_swapin_uncharge_swap(swp_entry_t entry);
		@@ -832,6 +837,10 @@ static inline void mem_cgroup_uncharge_list(struct list_head *page_list)
		__mem_cgroup_uncharge_list(page_list);
		}

		void mem_cgroup_cancel_charge(struct mem_cgroup *memcg, unsigned int nr_pages);

		void mem_cgroup_replace_folio(struct folio old, struct folio new);

		void mem_cgroup_migrate(struct folio old, struct folio new);

		/**
		@@ -888,6 +897,8 @@ struct mem_cgroup mem_cgroup_from_task(struct task_struct p);

		struct mem_cgroup get_mem_cgroup_from_mm(struct mm_struct mm);

		struct mem_cgroup *get_mem_cgroup_from_current(void);

		struct lruvec folio_lruvec_lock(struct folio folio);
		struct lruvec folio_lruvec_lock_irq(struct folio folio);
		struct lruvec folio_lruvec_lock_irqsave(struct folio folio,
		@@ -1388,12 +1399,23 @@ static inline bool mem_cgroup_below_min(struct mem_cgroup *target,
		return false;
		}

		static inline void mem_cgroup_commit_charge(struct folio *folio,
		struct mem_cgroup *memcg)
		{
		}

		static inline int mem_cgroup_charge(struct folio *folio,
		struct mm_struct *mm, gfp_t gfp)
		{
		return 0;
		}

		static inline int mem_cgroup_hugetlb_try_charge(struct mem_cgroup *memcg,
		gfp_t gfp, long nr_pages)
		{
		return 0;
		}

		static inline int mem_cgroup_swapin_charge_folio(struct folio *folio,
		struct mm_struct *mm, gfp_t gfp, swp_entry_t entry)
		{
		@@ -1412,6 +1434,16 @@ static inline void mem_cgroup_uncharge_list(struct list_head *page_list)
		{
		}

		static inline void mem_cgroup_cancel_charge(struct mem_cgroup *memcg,
		unsigned int nr_pages)
		{
		}

		static inline void mem_cgroup_replace_folio(struct folio *old,
		struct folio *new)
		{
		}

		static inline void mem_cgroup_migrate(struct folio old, struct folio new)
		{
		}
		@@ -1449,6 +1481,11 @@ static inline struct mem_cgroup get_mem_cgroup_from_mm(struct mm_struct mm)
		return NULL;
		}

		static inline struct mem_cgroup *get_mem_cgroup_from_current(void)
		{
		return NULL;
		}

		static inline
		struct mem_cgroup mem_cgroup_from_css(struct cgroup_subsys_state css)
		{

kernel/cgroup/cgroup.c

+14 −1

Original line number	Diff line number	Diff line
		@@ -1906,6 +1906,7 @@ enum cgroup2_param {
		Opt_favordynmods,
		Opt_memory_localevents,
		Opt_memory_recursiveprot,
		Opt_memory_hugetlb_accounting,
		nr__cgroup2_params
		};

		@@ -1914,6 +1915,7 @@ static const struct fs_parameter_spec cgroup2_fs_parameters[] = {
		fsparam_flag("favordynmods", Opt_favordynmods),
		fsparam_flag("memory_localevents", Opt_memory_localevents),
		fsparam_flag("memory_recursiveprot", Opt_memory_recursiveprot),
		fsparam_flag("memory_hugetlb_accounting", Opt_memory_hugetlb_accounting),
		{}
		};

		@@ -1940,6 +1942,9 @@ static int cgroup2_parse_param(struct fs_context fc, struct fs_parameter param
		case Opt_memory_recursiveprot:
		ctx->flags \|= CGRP_ROOT_MEMORY_RECURSIVE_PROT;
		return 0;
		case Opt_memory_hugetlb_accounting:
		ctx->flags \|= CGRP_ROOT_MEMORY_HUGETLB_ACCOUNTING;
		return 0;
		}
		return -EINVAL;
		}
		@@ -1964,6 +1969,11 @@ static void apply_cgroup_root_flags(unsigned int root_flags)
		cgrp_dfl_root.flags \|= CGRP_ROOT_MEMORY_RECURSIVE_PROT;
		else
		cgrp_dfl_root.flags &= ~CGRP_ROOT_MEMORY_RECURSIVE_PROT;

		if (root_flags & CGRP_ROOT_MEMORY_HUGETLB_ACCOUNTING)
		cgrp_dfl_root.flags \|= CGRP_ROOT_MEMORY_HUGETLB_ACCOUNTING;
		else
		cgrp_dfl_root.flags &= ~CGRP_ROOT_MEMORY_HUGETLB_ACCOUNTING;
		}
		}

		@@ -1977,6 +1987,8 @@ static int cgroup_show_options(struct seq_file seq, struct kernfs_root kf_root
		seq_puts(seq, ",memory_localevents");
		if (cgrp_dfl_root.flags & CGRP_ROOT_MEMORY_RECURSIVE_PROT)
		seq_puts(seq, ",memory_recursiveprot");
		if (cgrp_dfl_root.flags & CGRP_ROOT_MEMORY_HUGETLB_ACCOUNTING)
		seq_puts(seq, ",memory_hugetlb_accounting");
		return 0;
		}

		@@ -7163,7 +7175,8 @@ static ssize_t features_show(struct kobject kobj, struct kobj_attribute attr,
		"nsdelegate\n"
		"favordynmods\n"
		"memory_localevents\n"
		"memory_recursiveprot\n");
		"memory_recursiveprot\n"
		"memory_hugetlb_accounting\n");
		}
		static struct kobj_attribute cgroup_features_attr = __ATTR_RO(features);

mm/filemap.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -820,7 +820,7 @@ void replace_page_cache_folio(struct folio old, struct folio new)
		new->mapping = mapping;
		new->index = offset;

		mem_cgroup_migrate(old, new);
		mem_cgroup_replace_folio(old, new);

		xas_lock_irq(&xas);
		xas_store(&xas, new);