From 8b21ca0218d29cc6bb7028125c7e5a10dfb4730c Mon Sep 17 00:00:00 2001 From: Muchun Song Date: Fri, 13 Nov 2020 22:52:13 -0800 Subject: mm: memcontrol: fix missing wakeup polling thread When we poll the swap.events, we can miss being woken up when the swap event occurs. Because we didn't notify. Fixes: f3a53a3a1e5b ("mm, memcontrol: implement memory.swap.events") Signed-off-by: Muchun Song Signed-off-by: Andrew Morton Reviewed-by: Shakeel Butt Acked-by: Johannes Weiner Cc: Roman Gushchin Cc: Michal Hocko Cc: Yafang Shao Cc: Chris Down Cc: Tejun Heo Link: https://lkml.kernel.org/r/20201105161936.98312-1-songmuchun@bytedance.com Signed-off-by: Linus Torvalds --- include/linux/memcontrol.h | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) (limited to 'include/linux/memcontrol.h') diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h index e391e3c56de5..a80c59af2c60 100644 --- a/include/linux/memcontrol.h +++ b/include/linux/memcontrol.h @@ -900,12 +900,19 @@ static inline void count_memcg_event_mm(struct mm_struct *mm, static inline void memcg_memory_event(struct mem_cgroup *memcg, enum memcg_memory_event event) { + bool swap_event = event == MEMCG_SWAP_HIGH || event == MEMCG_SWAP_MAX || + event == MEMCG_SWAP_FAIL; + atomic_long_inc(&memcg->memory_events_local[event]); - cgroup_file_notify(&memcg->events_local_file); + if (!swap_event) + cgroup_file_notify(&memcg->events_local_file); do { atomic_long_inc(&memcg->memory_events[event]); - cgroup_file_notify(&memcg->events_file); + if (swap_event) + cgroup_file_notify(&memcg->swap_events_file); + else + cgroup_file_notify(&memcg->events_file); if (!cgroup_subsys_on_dfl(memory_cgrp_subsys)) break; -- cgit v1.3-14-g43fede From 4df910620bebb5cfe234af16ac8f6474b60215fd Mon Sep 17 00:00:00 2001 From: Feng Tang Date: Wed, 25 Nov 2020 13:22:21 +0800 Subject: mm: memcg: relayout structure mem_cgroup to avoid cache interference 0day reported one -22.7% regression for will-it-scale page_fault2 case [1] on a 4 sockets 144 CPU platform, and bisected to it to be caused by Waiman's optimization (commit bd0b230fe1) of saving one 'struct page_counter' space for 'struct mem_cgroup'. Initially we thought it was due to the cache alignment change introduced by the patch, but further debug shows that it is due to some hot data members ('vmstats_local', 'vmstats_percpu', 'vmstats') sit in 2 adjacent cacheline (2N and 2N+1 cacheline), and when adjacent cache line prefetch is enabled, it triggers an "extended level" of cache false sharing for 2 adjacent cache lines. So exchange the 2 member blocks, while keeping mostly the original cache alignment, which can restore and even enhance the performance, and save 64 bytes of space for 'struct mem_cgroup' (from 2880 to 2816, with 0day's default RHEL-8.3 kernel config) [1]. https://lore.kernel.org/lkml/20201102091543.GM31092@shao2-debian/ Fixes: bd0b230fe145 ("mm/memcg: unify swap and memsw page counters") Reported-by: kernel test robot Signed-off-by: Feng Tang Acked-by: Waiman Long Signed-off-by: Linus Torvalds --- include/linux/memcontrol.h | 28 ++++++++++++++-------------- 1 file changed, 14 insertions(+), 14 deletions(-) (limited to 'include/linux/memcontrol.h') diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h index a80c59af2c60..922a7f600465 100644 --- a/include/linux/memcontrol.h +++ b/include/linux/memcontrol.h @@ -282,20 +282,6 @@ struct mem_cgroup { MEMCG_PADDING(_pad1_); - /* - * set > 0 if pages under this cgroup are moving to other cgroup. - */ - atomic_t moving_account; - struct task_struct *move_lock_task; - - /* Legacy local VM stats and events */ - struct memcg_vmstats_percpu __percpu *vmstats_local; - - /* Subtree VM stats and events (batched updates) */ - struct memcg_vmstats_percpu __percpu *vmstats_percpu; - - MEMCG_PADDING(_pad2_); - atomic_long_t vmstats[MEMCG_NR_STAT]; atomic_long_t vmevents[NR_VM_EVENT_ITEMS]; @@ -317,6 +303,20 @@ struct mem_cgroup { struct list_head objcg_list; /* list of inherited objcgs */ #endif + MEMCG_PADDING(_pad2_); + + /* + * set > 0 if pages under this cgroup are moving to other cgroup. + */ + atomic_t moving_account; + struct task_struct *move_lock_task; + + /* Legacy local VM stats and events */ + struct memcg_vmstats_percpu __percpu *vmstats_local; + + /* Subtree VM stats and events (batched updates) */ + struct memcg_vmstats_percpu __percpu *vmstats_percpu; + #ifdef CONFIG_CGROUP_WRITEBACK struct list_head cgwb_list; struct wb_domain cgwb_domain; -- cgit v1.3-14-g43fede From bcfe06bf2622f7c4899468e427683aec49070687 Mon Sep 17 00:00:00 2001 From: Roman Gushchin Date: Tue, 1 Dec 2020 13:58:27 -0800 Subject: mm: memcontrol: Use helpers to read page's memcg data Patch series "mm: allow mapping accounted kernel pages to userspace", v6. Currently a non-slab kernel page which has been charged to a memory cgroup can't be mapped to userspace. The underlying reason is simple: PageKmemcg flag is defined as a page type (like buddy, offline, etc), so it takes a bit from a page->mapped counter. Pages with a type set can't be mapped to userspace. But in general the kmemcg flag has nothing to do with mapping to userspace. It only means that the page has been accounted by the page allocator, so it has to be properly uncharged on release. Some bpf maps are mapping the vmalloc-based memory to userspace, and their memory can't be accounted because of this implementation detail. This patchset removes this limitation by moving the PageKmemcg flag into one of the free bits of the page->mem_cgroup pointer. Also it formalizes accesses to the page->mem_cgroup and page->obj_cgroups using new helpers, adds several checks and removes a couple of obsolete functions. As the result the code became more robust with fewer open-coded bit tricks. This patch (of 4): Currently there are many open-coded reads of the page->mem_cgroup pointer, as well as a couple of read helpers, which are barely used. It creates an obstacle on a way to reuse some bits of the pointer for storing additional bits of information. In fact, we already do this for slab pages, where the last bit indicates that a pointer has an attached vector of objcg pointers instead of a regular memcg pointer. This commits uses 2 existing helpers and introduces a new helper to converts all read sides to calls of these helpers: struct mem_cgroup *page_memcg(struct page *page); struct mem_cgroup *page_memcg_rcu(struct page *page); struct mem_cgroup *page_memcg_check(struct page *page); page_memcg_check() is intended to be used in cases when the page can be a slab page and have a memcg pointer pointing at objcg vector. It does check the lowest bit, and if set, returns NULL. page_memcg() contains a VM_BUG_ON_PAGE() check for the page not being a slab page. To make sure nobody uses a direct access, struct page's mem_cgroup/obj_cgroups is converted to unsigned long memcg_data. Signed-off-by: Roman Gushchin Signed-off-by: Andrew Morton Signed-off-by: Alexei Starovoitov Reviewed-by: Shakeel Butt Acked-by: Johannes Weiner Acked-by: Michal Hocko Link: https://lkml.kernel.org/r/20201027001657.3398190-1-guro@fb.com Link: https://lkml.kernel.org/r/20201027001657.3398190-2-guro@fb.com Link: https://lore.kernel.org/bpf/20201201215900.3569844-2-guro@fb.com --- fs/buffer.c | 2 +- fs/iomap/buffered-io.c | 2 +- include/linux/memcontrol.h | 114 +++++++++++++++++++++++++++++++++--- include/linux/mm.h | 22 ------- include/linux/mm_types.h | 5 +- include/trace/events/writeback.h | 2 +- kernel/fork.c | 7 ++- mm/debug.c | 4 +- mm/huge_memory.c | 4 +- mm/memcontrol.c | 121 ++++++++++++++++++--------------------- mm/page_alloc.c | 4 +- mm/page_io.c | 6 +- mm/slab.h | 9 ++- mm/workingset.c | 2 +- 14 files changed, 184 insertions(+), 120 deletions(-) (limited to 'include/linux/memcontrol.h') diff --git a/fs/buffer.c b/fs/buffer.c index 23f645657488..b56f99f82b5b 100644 --- a/fs/buffer.c +++ b/fs/buffer.c @@ -657,7 +657,7 @@ int __set_page_dirty_buffers(struct page *page) } while (bh != head); } /* - * Lock out page->mem_cgroup migration to keep PageDirty + * Lock out page's memcg migration to keep PageDirty * synchronized with per-memcg dirty page counters. */ lock_page_memcg(page); diff --git a/fs/iomap/buffered-io.c b/fs/iomap/buffered-io.c index 10cc7979ce38..16a1e82e3aeb 100644 --- a/fs/iomap/buffered-io.c +++ b/fs/iomap/buffered-io.c @@ -650,7 +650,7 @@ iomap_set_page_dirty(struct page *page) return !TestSetPageDirty(page); /* - * Lock out page->mem_cgroup migration to keep PageDirty + * Lock out page's memcg migration to keep PageDirty * synchronized with per-memcg dirty page counters. */ lock_page_memcg(page); diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h index e391e3c56de5..f95c1433461c 100644 --- a/include/linux/memcontrol.h +++ b/include/linux/memcontrol.h @@ -343,6 +343,79 @@ struct mem_cgroup { extern struct mem_cgroup *root_mem_cgroup; +/* + * page_memcg - get the memory cgroup associated with a page + * @page: a pointer to the page struct + * + * Returns a pointer to the memory cgroup associated with the page, + * or NULL. This function assumes that the page is known to have a + * proper memory cgroup pointer. It's not safe to call this function + * against some type of pages, e.g. slab pages or ex-slab pages. + * + * Any of the following ensures page and memcg binding stability: + * - the page lock + * - LRU isolation + * - lock_page_memcg() + * - exclusive reference + */ +static inline struct mem_cgroup *page_memcg(struct page *page) +{ + VM_BUG_ON_PAGE(PageSlab(page), page); + return (struct mem_cgroup *)page->memcg_data; +} + +/* + * page_memcg_rcu - locklessly get the memory cgroup associated with a page + * @page: a pointer to the page struct + * + * Returns a pointer to the memory cgroup associated with the page, + * or NULL. This function assumes that the page is known to have a + * proper memory cgroup pointer. It's not safe to call this function + * against some type of pages, e.g. slab pages or ex-slab pages. + */ +static inline struct mem_cgroup *page_memcg_rcu(struct page *page) +{ + VM_BUG_ON_PAGE(PageSlab(page), page); + WARN_ON_ONCE(!rcu_read_lock_held()); + + return (struct mem_cgroup *)READ_ONCE(page->memcg_data); +} + +/* + * page_memcg_check - get the memory cgroup associated with a page + * @page: a pointer to the page struct + * + * Returns a pointer to the memory cgroup associated with the page, + * or NULL. This function unlike page_memcg() can take any page + * as an argument. It has to be used in cases when it's not known if a page + * has an associated memory cgroup pointer or an object cgroups vector. + * + * Any of the following ensures page and memcg binding stability: + * - the page lock + * - LRU isolation + * - lock_page_memcg() + * - exclusive reference + */ +static inline struct mem_cgroup *page_memcg_check(struct page *page) +{ + /* + * Because page->memcg_data might be changed asynchronously + * for slab pages, READ_ONCE() should be used here. + */ + unsigned long memcg_data = READ_ONCE(page->memcg_data); + + /* + * The lowest bit set means that memcg isn't a valid + * memcg pointer, but a obj_cgroups pointer. + * In this case the page is shared and doesn't belong + * to any specific memory cgroup. + */ + if (memcg_data & 0x1UL) + return NULL; + + return (struct mem_cgroup *)memcg_data; +} + static __always_inline bool memcg_stat_item_in_bytes(int idx) { if (idx == MEMCG_PERCPU_B) @@ -743,15 +816,19 @@ static inline void mod_memcg_state(struct mem_cgroup *memcg, static inline void __mod_memcg_page_state(struct page *page, int idx, int val) { - if (page->mem_cgroup) - __mod_memcg_state(page->mem_cgroup, idx, val); + struct mem_cgroup *memcg = page_memcg(page); + + if (memcg) + __mod_memcg_state(memcg, idx, val); } static inline void mod_memcg_page_state(struct page *page, int idx, int val) { - if (page->mem_cgroup) - mod_memcg_state(page->mem_cgroup, idx, val); + struct mem_cgroup *memcg = page_memcg(page); + + if (memcg) + mod_memcg_state(memcg, idx, val); } static inline unsigned long lruvec_page_state(struct lruvec *lruvec, @@ -834,16 +911,17 @@ static inline void __mod_lruvec_page_state(struct page *page, enum node_stat_item idx, int val) { struct page *head = compound_head(page); /* rmap on tail pages */ + struct mem_cgroup *memcg = page_memcg(head); pg_data_t *pgdat = page_pgdat(page); struct lruvec *lruvec; /* Untracked pages have no memcg, no lruvec. Update only the node */ - if (!head->mem_cgroup) { + if (!memcg) { __mod_node_page_state(pgdat, idx, val); return; } - lruvec = mem_cgroup_lruvec(head->mem_cgroup, pgdat); + lruvec = mem_cgroup_lruvec(memcg, pgdat); __mod_lruvec_state(lruvec, idx, val); } @@ -878,8 +956,10 @@ static inline void count_memcg_events(struct mem_cgroup *memcg, static inline void count_memcg_page_event(struct page *page, enum vm_event_item idx) { - if (page->mem_cgroup) - count_memcg_events(page->mem_cgroup, idx, 1); + struct mem_cgroup *memcg = page_memcg(page); + + if (memcg) + count_memcg_events(memcg, idx, 1); } static inline void count_memcg_event_mm(struct mm_struct *mm, @@ -941,6 +1021,22 @@ void mem_cgroup_split_huge_fixup(struct page *head); struct mem_cgroup; +static inline struct mem_cgroup *page_memcg(struct page *page) +{ + return NULL; +} + +static inline struct mem_cgroup *page_memcg_rcu(struct page *page) +{ + WARN_ON_ONCE(!rcu_read_lock_held()); + return NULL; +} + +static inline struct mem_cgroup *page_memcg_check(struct page *page) +{ + return NULL; +} + static inline bool mem_cgroup_is_root(struct mem_cgroup *memcg) { return true; @@ -1430,7 +1526,7 @@ static inline void mem_cgroup_track_foreign_dirty(struct page *page, if (mem_cgroup_disabled()) return; - if (unlikely(&page->mem_cgroup->css != wb->memcg_css)) + if (unlikely(&page_memcg(page)->css != wb->memcg_css)) mem_cgroup_track_foreign_dirty_slowpath(page, wb); } diff --git a/include/linux/mm.h b/include/linux/mm.h index db6ae4d3fb4e..6b0c9d2c1d10 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -1484,28 +1484,6 @@ static inline void set_page_links(struct page *page, enum zone_type zone, #endif } -#ifdef CONFIG_MEMCG -static inline struct mem_cgroup *page_memcg(struct page *page) -{ - return page->mem_cgroup; -} -static inline struct mem_cgroup *page_memcg_rcu(struct page *page) -{ - WARN_ON_ONCE(!rcu_read_lock_held()); - return READ_ONCE(page->mem_cgroup); -} -#else -static inline struct mem_cgroup *page_memcg(struct page *page) -{ - return NULL; -} -static inline struct mem_cgroup *page_memcg_rcu(struct page *page) -{ - WARN_ON_ONCE(!rcu_read_lock_held()); - return NULL; -} -#endif - /* * Some inline functions in vmstat.h depend on page_zone() */ diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h index 5a9238f6caad..80f5d755c037 100644 --- a/include/linux/mm_types.h +++ b/include/linux/mm_types.h @@ -199,10 +199,7 @@ struct page { atomic_t _refcount; #ifdef CONFIG_MEMCG - union { - struct mem_cgroup *mem_cgroup; - struct obj_cgroup **obj_cgroups; - }; + unsigned long memcg_data; #endif /* diff --git a/include/trace/events/writeback.h b/include/trace/events/writeback.h index e7cbccc7c14c..39a40dfb578a 100644 --- a/include/trace/events/writeback.h +++ b/include/trace/events/writeback.h @@ -257,7 +257,7 @@ TRACE_EVENT(track_foreign_dirty, __entry->ino = inode ? inode->i_ino : 0; __entry->memcg_id = wb->memcg_css->id; __entry->cgroup_ino = __trace_wb_assign_cgroup(wb); - __entry->page_cgroup_ino = cgroup_ino(page->mem_cgroup->css.cgroup); + __entry->page_cgroup_ino = cgroup_ino(page_memcg(page)->css.cgroup); ), TP_printk("bdi %s[%llu]: ino=%lu memcg_id=%u cgroup_ino=%lu page_cgroup_ino=%lu", diff --git a/kernel/fork.c b/kernel/fork.c index 6d266388d380..cbd4f6f58409 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -404,9 +404,10 @@ static int memcg_charge_kernel_stack(struct task_struct *tsk) for (i = 0; i < THREAD_SIZE / PAGE_SIZE; i++) { /* - * If memcg_kmem_charge_page() fails, page->mem_cgroup - * pointer is NULL, and memcg_kmem_uncharge_page() in - * free_thread_stack() will ignore this page. + * If memcg_kmem_charge_page() fails, page's + * memory cgroup pointer is NULL, and + * memcg_kmem_uncharge_page() in free_thread_stack() + * will ignore this page. */ ret = memcg_kmem_charge_page(vm->pages[i], GFP_KERNEL, 0); diff --git a/mm/debug.c b/mm/debug.c index ccca576b2899..8a40b3fefbeb 100644 --- a/mm/debug.c +++ b/mm/debug.c @@ -182,8 +182,8 @@ hex_only: pr_warn("page dumped because: %s\n", reason); #ifdef CONFIG_MEMCG - if (!page_poisoned && page->mem_cgroup) - pr_warn("page->mem_cgroup:%px\n", page->mem_cgroup); + if (!page_poisoned && page->memcg_data) + pr_warn("pages's memcg:%lx\n", page->memcg_data); #endif } diff --git a/mm/huge_memory.c b/mm/huge_memory.c index 9474dbc150ed..cedfb3503411 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -470,7 +470,7 @@ pmd_t maybe_pmd_mkwrite(pmd_t pmd, struct vm_area_struct *vma) #ifdef CONFIG_MEMCG static inline struct deferred_split *get_deferred_split_queue(struct page *page) { - struct mem_cgroup *memcg = compound_head(page)->mem_cgroup; + struct mem_cgroup *memcg = page_memcg(compound_head(page)); struct pglist_data *pgdat = NODE_DATA(page_to_nid(page)); if (memcg) @@ -2765,7 +2765,7 @@ void deferred_split_huge_page(struct page *page) { struct deferred_split *ds_queue = get_deferred_split_queue(page); #ifdef CONFIG_MEMCG - struct mem_cgroup *memcg = compound_head(page)->mem_cgroup; + struct mem_cgroup *memcg = page_memcg(compound_head(page)); #endif unsigned long flags; diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 3dcbf24d2227..3968d68503cb 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -533,7 +533,7 @@ struct cgroup_subsys_state *mem_cgroup_css_from_page(struct page *page) { struct mem_cgroup *memcg; - memcg = page->mem_cgroup; + memcg = page_memcg(page); if (!memcg || !cgroup_subsys_on_dfl(memory_cgrp_subsys)) memcg = root_mem_cgroup; @@ -560,16 +560,7 @@ ino_t page_cgroup_ino(struct page *page) unsigned long ino = 0; rcu_read_lock(); - memcg = page->mem_cgroup; - - /* - * The lowest bit set means that memcg isn't a valid - * memcg pointer, but a obj_cgroups pointer. - * In this case the page is shared and doesn't belong - * to any specific memory cgroup. - */ - if ((unsigned long) memcg & 0x1UL) - memcg = NULL; + memcg = page_memcg_check(page); while (memcg && !(memcg->css.flags & CSS_ONLINE)) memcg = parent_mem_cgroup(memcg); @@ -1050,7 +1041,7 @@ EXPORT_SYMBOL(get_mem_cgroup_from_mm); */ struct mem_cgroup *get_mem_cgroup_from_page(struct page *page) { - struct mem_cgroup *memcg = page->mem_cgroup; + struct mem_cgroup *memcg = page_memcg(page); if (mem_cgroup_disabled()) return NULL; @@ -1349,7 +1340,7 @@ struct lruvec *mem_cgroup_page_lruvec(struct page *page, struct pglist_data *pgd goto out; } - memcg = page->mem_cgroup; + memcg = page_memcg(page); /* * Swapcache readahead pages are added to the LRU - and * possibly migrated - before they are charged. @@ -2109,7 +2100,7 @@ void mem_cgroup_print_oom_group(struct mem_cgroup *memcg) } /** - * lock_page_memcg - lock a page->mem_cgroup binding + * lock_page_memcg - lock a page and memcg binding * @page: the page * * This function protects unlocked LRU pages from being moved to @@ -2141,7 +2132,7 @@ struct mem_cgroup *lock_page_memcg(struct page *page) if (mem_cgroup_disabled()) return NULL; again: - memcg = head->mem_cgroup; + memcg = page_memcg(head); if (unlikely(!memcg)) return NULL; @@ -2149,7 +2140,7 @@ again: return memcg; spin_lock_irqsave(&memcg->move_lock, flags); - if (memcg != head->mem_cgroup) { + if (memcg != page_memcg(head)) { spin_unlock_irqrestore(&memcg->move_lock, flags); goto again; } @@ -2187,14 +2178,14 @@ void __unlock_page_memcg(struct mem_cgroup *memcg) } /** - * unlock_page_memcg - unlock a page->mem_cgroup binding + * unlock_page_memcg - unlock a page and memcg binding * @page: the page */ void unlock_page_memcg(struct page *page) { struct page *head = compound_head(page); - __unlock_page_memcg(head->mem_cgroup); + __unlock_page_memcg(page_memcg(head)); } EXPORT_SYMBOL(unlock_page_memcg); @@ -2884,7 +2875,7 @@ static void cancel_charge(struct mem_cgroup *memcg, unsigned int nr_pages) static void commit_charge(struct page *page, struct mem_cgroup *memcg) { - VM_BUG_ON_PAGE(page->mem_cgroup, page); + VM_BUG_ON_PAGE(page_memcg(page), page); /* * Any of the following ensures page->mem_cgroup stability: * @@ -2893,7 +2884,7 @@ static void commit_charge(struct page *page, struct mem_cgroup *memcg) * - lock_page_memcg() * - exclusive reference */ - page->mem_cgroup = memcg; + page->memcg_data = (unsigned long)memcg; } #ifdef CONFIG_MEMCG_KMEM @@ -2908,8 +2899,7 @@ int memcg_alloc_page_obj_cgroups(struct page *page, struct kmem_cache *s, if (!vec) return -ENOMEM; - if (cmpxchg(&page->obj_cgroups, NULL, - (struct obj_cgroup **) ((unsigned long)vec | 0x1UL))) + if (cmpxchg(&page->memcg_data, 0, (unsigned long)vec | 0x1UL)) kfree(vec); else kmemleak_not_leak(vec); @@ -2920,6 +2910,12 @@ int memcg_alloc_page_obj_cgroups(struct page *page, struct kmem_cache *s, /* * Returns a pointer to the memory cgroup to which the kernel object is charged. * + * A passed kernel object can be a slab object or a generic kernel page, so + * different mechanisms for getting the memory cgroup pointer should be used. + * In certain cases (e.g. kernel stacks or large kmallocs with SLUB) the caller + * can not know for sure how the kernel object is implemented. + * mem_cgroup_from_obj() can be safely used in such cases. + * * The caller must ensure the memcg lifetime, e.g. by taking rcu_read_lock(), * cgroup_mutex, etc. */ @@ -2932,17 +2928,6 @@ struct mem_cgroup *mem_cgroup_from_obj(void *p) page = virt_to_head_page(p); - /* - * If page->mem_cgroup is set, it's either a simple mem_cgroup pointer - * or a pointer to obj_cgroup vector. In the latter case the lowest - * bit of the pointer is set. - * The page->mem_cgroup pointer can be asynchronously changed - * from NULL to (obj_cgroup_vec | 0x1UL), but can't be changed - * from a valid memcg pointer to objcg vector or back. - */ - if (!page->mem_cgroup) - return NULL; - /* * Slab objects are accounted individually, not per-page. * Memcg membership data for each individual object is saved in @@ -2960,8 +2945,14 @@ struct mem_cgroup *mem_cgroup_from_obj(void *p) return NULL; } - /* All other pages use page->mem_cgroup */ - return page->mem_cgroup; + /* + * page_memcg_check() is used here, because page_has_obj_cgroups() + * check above could fail because the object cgroups vector wasn't set + * at that moment, but it can be set concurrently. + * page_memcg_check(page) will guarantee that a proper memory + * cgroup pointer or NULL will be returned. + */ + return page_memcg_check(page); } __always_inline struct obj_cgroup *get_obj_cgroup_from_current(void) @@ -3099,7 +3090,7 @@ int __memcg_kmem_charge_page(struct page *page, gfp_t gfp, int order) if (memcg && !mem_cgroup_is_root(memcg)) { ret = __memcg_kmem_charge(memcg, gfp, 1 << order); if (!ret) { - page->mem_cgroup = memcg; + page->memcg_data = (unsigned long)memcg; __SetPageKmemcg(page); return 0; } @@ -3115,7 +3106,7 @@ int __memcg_kmem_charge_page(struct page *page, gfp_t gfp, int order) */ void __memcg_kmem_uncharge_page(struct page *page, int order) { - struct mem_cgroup *memcg = page->mem_cgroup; + struct mem_cgroup *memcg = page_memcg(page); unsigned int nr_pages = 1 << order; if (!memcg) @@ -3123,7 +3114,7 @@ void __memcg_kmem_uncharge_page(struct page *page, int order) VM_BUG_ON_PAGE(mem_cgroup_is_root(memcg), page); __memcg_kmem_uncharge(memcg, nr_pages); - page->mem_cgroup = NULL; + page->memcg_data = 0; css_put(&memcg->css); /* slab pages do not have PageKmemcg flag set */ @@ -3274,7 +3265,7 @@ void obj_cgroup_uncharge(struct obj_cgroup *objcg, size_t size) */ void mem_cgroup_split_huge_fixup(struct page *head) { - struct mem_cgroup *memcg = head->mem_cgroup; + struct mem_cgroup *memcg = page_memcg(head); int i; if (mem_cgroup_disabled()) @@ -3282,7 +3273,7 @@ void mem_cgroup_split_huge_fixup(struct page *head) for (i = 1; i < HPAGE_PMD_NR; i++) { css_get(&memcg->css); - head[i].mem_cgroup = memcg; + head[i].memcg_data = (unsigned long)memcg; } } #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ @@ -4664,7 +4655,7 @@ void mem_cgroup_wb_stats(struct bdi_writeback *wb, unsigned long *pfilepages, void mem_cgroup_track_foreign_dirty_slowpath(struct page *page, struct bdi_writeback *wb) { - struct mem_cgroup *memcg = page->mem_cgroup; + struct mem_cgroup *memcg = page_memcg(page); struct memcg_cgwb_frn *frn; u64 now = get_jiffies_64(); u64 oldest_at = now; @@ -5641,14 +5632,14 @@ static int mem_cgroup_move_account(struct page *page, /* * Prevent mem_cgroup_migrate() from looking at - * page->mem_cgroup of its source page while we change it. + * page's memory cgroup of its source page while we change it. */ ret = -EBUSY; if (!trylock_page(page)) goto out; ret = -EINVAL; - if (page->mem_cgroup != from) + if (page_memcg(page) != from) goto out_unlock; pgdat = page_pgdat(page); @@ -5703,13 +5694,13 @@ static int mem_cgroup_move_account(struct page *page, /* * All state has been migrated, let's switch to the new memcg. * - * It is safe to change page->mem_cgroup here because the page + * It is safe to change page's memcg here because the page * is referenced, charged, isolated, and locked: we can't race * with (un)charging, migration, LRU putback, or anything else - * that would rely on a stable page->mem_cgroup. + * that would rely on a stable page's memory cgroup. * * Note that lock_page_memcg is a memcg lock, not a page lock, - * to save space. As soon as we switch page->mem_cgroup to a + * to save space. As soon as we switch page's memory cgroup to a * new memcg that isn't locked, the above state can change * concurrently again. Make sure we're truly done with it. */ @@ -5718,7 +5709,7 @@ static int mem_cgroup_move_account(struct page *page, css_get(&to->css); css_put(&from->css); - page->mem_cgroup = to; + page->memcg_data = (unsigned long)to; __unlock_page_memcg(from); @@ -5784,7 +5775,7 @@ static enum mc_target_type get_mctgt_type(struct vm_area_struct *vma, * mem_cgroup_move_account() checks the page is valid or * not under LRU exclusion. */ - if (page->mem_cgroup == mc.from) { + if (page_memcg(page) == mc.from) { ret = MC_TARGET_PAGE; if (is_device_private_page(page)) ret = MC_TARGET_DEVICE; @@ -5828,7 +5819,7 @@ static enum mc_target_type get_mctgt_type_thp(struct vm_area_struct *vma, VM_BUG_ON_PAGE(!page || !PageHead(page), page); if (!(mc.flags & MOVE_ANON)) return ret; - if (page->mem_cgroup == mc.from) { + if (page_memcg(page) == mc.from) { ret = MC_TARGET_PAGE; if (target) { get_page(page); @@ -6774,12 +6765,12 @@ int mem_cgroup_charge(struct page *page, struct mm_struct *mm, gfp_t gfp_mask) /* * Every swap fault against a single page tries to charge the * page, bail as early as possible. shmem_unuse() encounters - * already charged pages, too. page->mem_cgroup is protected - * by the page lock, which serializes swap cache removal, which - * in turn serializes uncharging. + * already charged pages, too. page and memcg binding is + * protected by the page lock, which serializes swap cache + * removal, which in turn serializes uncharging. */ VM_BUG_ON_PAGE(!PageLocked(page), page); - if (compound_head(page)->mem_cgroup) + if (page_memcg(compound_head(page))) goto out; id = lookup_swap_cgroup_id(ent); @@ -6863,21 +6854,21 @@ static void uncharge_page(struct page *page, struct uncharge_gather *ug) VM_BUG_ON_PAGE(PageLRU(page), page); - if (!page->mem_cgroup) + if (!page_memcg(page)) return; /* * Nobody should be changing or seriously looking at - * page->mem_cgroup at this point, we have fully + * page_memcg(page) at this point, we have fully * exclusive access to the page. */ - if (ug->memcg != page->mem_cgroup) { + if (ug->memcg != page_memcg(page)) { if (ug->memcg) { uncharge_batch(ug); uncharge_gather_clear(ug); } - ug->memcg = page->mem_cgroup; + ug->memcg = page_memcg(page); /* pairs with css_put in uncharge_batch */ css_get(&ug->memcg->css); @@ -6894,7 +6885,7 @@ static void uncharge_page(struct page *page, struct uncharge_gather *ug) } ug->dummy_page = page; - page->mem_cgroup = NULL; + page->memcg_data = 0; css_put(&ug->memcg->css); } @@ -6937,7 +6928,7 @@ void mem_cgroup_uncharge(struct page *page) return; /* Don't touch page->lru of any random page, pre-check: */ - if (!page->mem_cgroup) + if (!page_memcg(page)) return; uncharge_gather_clear(&ug); @@ -6987,11 +6978,11 @@ void mem_cgroup_migrate(struct page *oldpage, struct page *newpage) return; /* Page cache replacement: new page already charged? */ - if (newpage->mem_cgroup) + if (page_memcg(newpage)) return; /* Swapcache readahead pages can get replaced before being charged */ - memcg = oldpage->mem_cgroup; + memcg = page_memcg(oldpage); if (!memcg) return; @@ -7186,7 +7177,7 @@ void mem_cgroup_swapout(struct page *page, swp_entry_t entry) if (cgroup_subsys_on_dfl(memory_cgrp_subsys)) return; - memcg = page->mem_cgroup; + memcg = page_memcg(page); /* Readahead page, never charged */ if (!memcg) @@ -7207,7 +7198,7 @@ void mem_cgroup_swapout(struct page *page, swp_entry_t entry) VM_BUG_ON_PAGE(oldid, page); mod_memcg_state(swap_memcg, MEMCG_SWAP, nr_entries); - page->mem_cgroup = NULL; + page->memcg_data = 0; if (!mem_cgroup_is_root(memcg)) page_counter_uncharge(&memcg->memory, nr_entries); @@ -7250,7 +7241,7 @@ int mem_cgroup_try_charge_swap(struct page *page, swp_entry_t entry) if (!cgroup_subsys_on_dfl(memory_cgrp_subsys)) return 0; - memcg = page->mem_cgroup; + memcg = page_memcg(page); /* Readahead page, never charged */ if (!memcg) @@ -7331,7 +7322,7 @@ bool mem_cgroup_swap_full(struct page *page) if (cgroup_memory_noswap || !cgroup_subsys_on_dfl(memory_cgrp_subsys)) return false; - memcg = page->mem_cgroup; + memcg = page_memcg(page); if (!memcg) return false; diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 23f5066bd4a5..271133b8243b 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -1092,7 +1092,7 @@ static inline bool page_expected_state(struct page *page, if (unlikely((unsigned long)page->mapping | page_ref_count(page) | #ifdef CONFIG_MEMCG - (unsigned long)page->mem_cgroup | + (unsigned long)page_memcg(page) | #endif (page->flags & check_flags))) return false; @@ -1117,7 +1117,7 @@ static const char *page_bad_reason(struct page *page, unsigned long flags) bad_reason = "PAGE_FLAGS_CHECK_AT_FREE flag(s) set"; } #ifdef CONFIG_MEMCG - if (unlikely(page->mem_cgroup)) + if (unlikely(page_memcg(page))) bad_reason = "page still charged to cgroup"; #endif return bad_reason; diff --git a/mm/page_io.c b/mm/page_io.c index 433df1263349..9bca17ecc4df 100644 --- a/mm/page_io.c +++ b/mm/page_io.c @@ -291,12 +291,14 @@ static inline void count_swpout_vm_event(struct page *page) static void bio_associate_blkg_from_page(struct bio *bio, struct page *page) { struct cgroup_subsys_state *css; + struct mem_cgroup *memcg; - if (!page->mem_cgroup) + memcg = page_memcg(page); + if (!memcg) return; rcu_read_lock(); - css = cgroup_e_css(page->mem_cgroup->css.cgroup, &io_cgrp_subsys); + css = cgroup_e_css(memcg->css.cgroup, &io_cgrp_subsys); bio_associate_blkg_from_css(bio, css); rcu_read_unlock(); } diff --git a/mm/slab.h b/mm/slab.h index 6d7c6a5056ba..e2535cee0d33 100644 --- a/mm/slab.h +++ b/mm/slab.h @@ -242,18 +242,17 @@ static inline bool kmem_cache_debug_flags(struct kmem_cache *s, slab_flags_t fla static inline struct obj_cgroup **page_obj_cgroups(struct page *page) { /* - * page->mem_cgroup and page->obj_cgroups are sharing the same + * Page's memory cgroup and obj_cgroups vector are sharing the same * space. To distinguish between them in case we don't know for sure * that the page is a slab page (e.g. page_cgroup_ino()), let's * always set the lowest bit of obj_cgroups. */ - return (struct obj_cgroup **) - ((unsigned long)page->obj_cgroups & ~0x1UL); + return (struct obj_cgroup **)(page->memcg_data & ~0x1UL); } static inline bool page_has_obj_cgroups(struct page *page) { - return ((unsigned long)page->obj_cgroups & 0x1UL); + return page->memcg_data & 0x1UL; } int memcg_alloc_page_obj_cgroups(struct page *page, struct kmem_cache *s, @@ -262,7 +261,7 @@ int memcg_alloc_page_obj_cgroups(struct page *page, struct kmem_cache *s, static inline void memcg_free_page_obj_cgroups(struct page *page) { kfree(page_obj_cgroups(page)); - page->obj_cgroups = NULL; + page->memcg_data = 0; } static inline size_t obj_full_size(struct kmem_cache *s) diff --git a/mm/workingset.c b/mm/workingset.c index 975a4d2dd02e..130348cbf40a 100644 --- a/mm/workingset.c +++ b/mm/workingset.c @@ -257,7 +257,7 @@ void *workingset_eviction(struct page *page, struct mem_cgroup *target_memcg) struct lruvec *lruvec; int memcgid; - /* Page is fully exclusive and pins page->mem_cgroup */ + /* Page is fully exclusive and pins page's memory cgroup pointer */ VM_BUG_ON_PAGE(PageLRU(page), page); VM_BUG_ON_PAGE(page_count(page), page); VM_BUG_ON_PAGE(!PageLocked(page), page); -- cgit v1.3-14-g43fede From 270c6a71460e12b07b1dcadf7457ff95b6c6e8f4 Mon Sep 17 00:00:00 2001 From: Roman Gushchin Date: Tue, 1 Dec 2020 13:58:28 -0800 Subject: mm: memcontrol/slab: Use helpers to access slab page's memcg_data To gather all direct accesses to struct page's memcg_data field in one place, let's introduce 3 new helpers to use in the slab accounting code: struct obj_cgroup **page_objcgs(struct page *page); struct obj_cgroup **page_objcgs_check(struct page *page); bool set_page_objcgs(struct page *page, struct obj_cgroup **objcgs); They are similar to the corresponding API for generic pages, except that the setter can return false, indicating that the value has been already set from a different thread. Signed-off-by: Roman Gushchin Signed-off-by: Andrew Morton Signed-off-by: Alexei Starovoitov Reviewed-by: Shakeel Butt Acked-by: Johannes Weiner Link: https://lkml.kernel.org/r/20201027001657.3398190-3-guro@fb.com Link: https://lore.kernel.org/bpf/20201201215900.3569844-3-guro@fb.com --- include/linux/memcontrol.h | 64 ++++++++++++++++++++++++++++++++++++++++++++++ mm/memcontrol.c | 6 ++--- mm/slab.h | 35 ++++++------------------- 3 files changed, 75 insertions(+), 30 deletions(-) (limited to 'include/linux/memcontrol.h') diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h index f95c1433461c..c7ac0a5b8989 100644 --- a/include/linux/memcontrol.h +++ b/include/linux/memcontrol.h @@ -416,6 +416,70 @@ static inline struct mem_cgroup *page_memcg_check(struct page *page) return (struct mem_cgroup *)memcg_data; } +#ifdef CONFIG_MEMCG_KMEM +/* + * page_objcgs - get the object cgroups vector associated with a page + * @page: a pointer to the page struct + * + * Returns a pointer to the object cgroups vector associated with the page, + * or NULL. This function assumes that the page is known to have an + * associated object cgroups vector. It's not safe to call this function + * against pages, which might have an associated memory cgroup: e.g. + * kernel stack pages. + */ +static inline struct obj_cgroup **page_objcgs(struct page *page) +{ + return (struct obj_cgroup **)(READ_ONCE(page->memcg_data) & ~0x1UL); +} + +/* + * page_objcgs_check - get the object cgroups vector associated with a page + * @page: a pointer to the page struct + * + * Returns a pointer to the object cgroups vector associated with the page, + * or NULL. This function is safe to use if the page can be directly associated + * with a memory cgroup. + */ +static inline struct obj_cgroup **page_objcgs_check(struct page *page) +{ + unsigned long memcg_data = READ_ONCE(page->memcg_data); + + if (memcg_data && (memcg_data & 0x1UL)) + return (struct obj_cgroup **)(memcg_data & ~0x1UL); + + return NULL; +} + +/* + * set_page_objcgs - associate a page with a object cgroups vector + * @page: a pointer to the page struct + * @objcgs: a pointer to the object cgroups vector + * + * Atomically associates a page with a vector of object cgroups. + */ +static inline bool set_page_objcgs(struct page *page, + struct obj_cgroup **objcgs) +{ + return !cmpxchg(&page->memcg_data, 0, (unsigned long)objcgs | 0x1UL); +} +#else +static inline struct obj_cgroup **page_objcgs(struct page *page) +{ + return NULL; +} + +static inline struct obj_cgroup **page_objcgs_check(struct page *page) +{ + return NULL; +} + +static inline bool set_page_objcgs(struct page *page, + struct obj_cgroup **objcgs) +{ + return true; +} +#endif + static __always_inline bool memcg_stat_item_in_bytes(int idx) { if (idx == MEMCG_PERCPU_B) diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 3968d68503cb..0054b4846770 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -2899,7 +2899,7 @@ int memcg_alloc_page_obj_cgroups(struct page *page, struct kmem_cache *s, if (!vec) return -ENOMEM; - if (cmpxchg(&page->memcg_data, 0, (unsigned long)vec | 0x1UL)) + if (!set_page_objcgs(page, vec)) kfree(vec); else kmemleak_not_leak(vec); @@ -2933,12 +2933,12 @@ struct mem_cgroup *mem_cgroup_from_obj(void *p) * Memcg membership data for each individual object is saved in * the page->obj_cgroups. */ - if (page_has_obj_cgroups(page)) { + if (page_objcgs_check(page)) { struct obj_cgroup *objcg; unsigned int off; off = obj_to_index(page->slab_cache, page, p); - objcg = page_obj_cgroups(page)[off]; + objcg = page_objcgs(page)[off]; if (objcg) return obj_cgroup_memcg(objcg); diff --git a/mm/slab.h b/mm/slab.h index e2535cee0d33..9a54a0cb5cca 100644 --- a/mm/slab.h +++ b/mm/slab.h @@ -239,28 +239,12 @@ static inline bool kmem_cache_debug_flags(struct kmem_cache *s, slab_flags_t fla } #ifdef CONFIG_MEMCG_KMEM -static inline struct obj_cgroup **page_obj_cgroups(struct page *page) -{ - /* - * Page's memory cgroup and obj_cgroups vector are sharing the same - * space. To distinguish between them in case we don't know for sure - * that the page is a slab page (e.g. page_cgroup_ino()), let's - * always set the lowest bit of obj_cgroups. - */ - return (struct obj_cgroup **)(page->memcg_data & ~0x1UL); -} - -static inline bool page_has_obj_cgroups(struct page *page) -{ - return page->memcg_data & 0x1UL; -} - int memcg_alloc_page_obj_cgroups(struct page *page, struct kmem_cache *s, gfp_t gfp); static inline void memcg_free_page_obj_cgroups(struct page *page) { - kfree(page_obj_cgroups(page)); + kfree(page_objcgs(page)); page->memcg_data = 0; } @@ -322,7 +306,7 @@ static inline void memcg_slab_post_alloc_hook(struct kmem_cache *s, if (likely(p[i])) { page = virt_to_head_page(p[i]); - if (!page_has_obj_cgroups(page) && + if (!page_objcgs(page) && memcg_alloc_page_obj_cgroups(page, s, flags)) { obj_cgroup_uncharge(objcg, obj_full_size(s)); continue; @@ -330,7 +314,7 @@ static inline void memcg_slab_post_alloc_hook(struct kmem_cache *s, off = obj_to_index(s, page, p[i]); obj_cgroup_get(objcg); - page_obj_cgroups(page)[off] = objcg; + page_objcgs(page)[off] = objcg; mod_objcg_state(objcg, page_pgdat(page), cache_vmstat_idx(s), obj_full_size(s)); } else { @@ -344,6 +328,7 @@ static inline void memcg_slab_free_hook(struct kmem_cache *s_orig, void **p, int objects) { struct kmem_cache *s; + struct obj_cgroup **objcgs; struct obj_cgroup *objcg; struct page *page; unsigned int off; @@ -357,7 +342,8 @@ static inline void memcg_slab_free_hook(struct kmem_cache *s_orig, continue; page = virt_to_head_page(p[i]); - if (!page_has_obj_cgroups(page)) + objcgs = page_objcgs(page); + if (!objcgs) continue; if (!s_orig) @@ -366,11 +352,11 @@ static inline void memcg_slab_free_hook(struct kmem_cache *s_orig, s = s_orig; off = obj_to_index(s, page, p[i]); - objcg = page_obj_cgroups(page)[off]; + objcg = objcgs[off]; if (!objcg) continue; - page_obj_cgroups(page)[off] = NULL; + objcgs[off] = NULL; obj_cgroup_uncharge(objcg, obj_full_size(s)); mod_objcg_state(objcg, page_pgdat(page), cache_vmstat_idx(s), -obj_full_size(s)); @@ -379,11 +365,6 @@ static inline void memcg_slab_free_hook(struct kmem_cache *s_orig, } #else /* CONFIG_MEMCG_KMEM */ -static inline bool page_has_obj_cgroups(struct page *page) -{ - return false; -} - static inline struct mem_cgroup *memcg_from_slab_obj(void *ptr) { return NULL; -- cgit v1.3-14-g43fede From 87944e2992bd28098c6806086a1e96bb4d0e502b Mon Sep 17 00:00:00 2001 From: Roman Gushchin Date: Tue, 1 Dec 2020 13:58:29 -0800 Subject: mm: Introduce page memcg flags The lowest bit in page->memcg_data is used to distinguish between struct memory_cgroup pointer and a pointer to a objcgs array. All checks and modifications of this bit are open-coded. Let's formalize it using page memcg flags, defined in enum page_memcg_data_flags. Additional flags might be added later. Signed-off-by: Roman Gushchin Signed-off-by: Andrew Morton Signed-off-by: Alexei Starovoitov Reviewed-by: Shakeel Butt Acked-by: Johannes Weiner Acked-by: Michal Hocko Link: https://lkml.kernel.org/r/20201027001657.3398190-4-guro@fb.com Link: https://lore.kernel.org/bpf/20201201215900.3569844-4-guro@fb.com --- include/linux/memcontrol.h | 32 ++++++++++++++++++++------------ 1 file changed, 20 insertions(+), 12 deletions(-) (limited to 'include/linux/memcontrol.h') diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h index c7ac0a5b8989..99a4841d658b 100644 --- a/include/linux/memcontrol.h +++ b/include/linux/memcontrol.h @@ -343,6 +343,15 @@ struct mem_cgroup { extern struct mem_cgroup *root_mem_cgroup; +enum page_memcg_data_flags { + /* page->memcg_data is a pointer to an objcgs vector */ + MEMCG_DATA_OBJCGS = (1UL << 0), + /* the next bit after the last actual flag */ + __NR_MEMCG_DATA_FLAGS = (1UL << 1), +}; + +#define MEMCG_DATA_FLAGS_MASK (__NR_MEMCG_DATA_FLAGS - 1) + /* * page_memcg - get the memory cgroup associated with a page * @page: a pointer to the page struct @@ -404,13 +413,7 @@ static inline struct mem_cgroup *page_memcg_check(struct page *page) */ unsigned long memcg_data = READ_ONCE(page->memcg_data); - /* - * The lowest bit set means that memcg isn't a valid - * memcg pointer, but a obj_cgroups pointer. - * In this case the page is shared and doesn't belong - * to any specific memory cgroup. - */ - if (memcg_data & 0x1UL) + if (memcg_data & MEMCG_DATA_OBJCGS) return NULL; return (struct mem_cgroup *)memcg_data; @@ -429,7 +432,11 @@ static inline struct mem_cgroup *page_memcg_check(struct page *page) */ static inline struct obj_cgroup **page_objcgs(struct page *page) { - return (struct obj_cgroup **)(READ_ONCE(page->memcg_data) & ~0x1UL); + unsigned long memcg_data = READ_ONCE(page->memcg_data); + + VM_BUG_ON_PAGE(memcg_data && !(memcg_data & MEMCG_DATA_OBJCGS), page); + + return (struct obj_cgroup **)(memcg_data & ~MEMCG_DATA_FLAGS_MASK); } /* @@ -444,10 +451,10 @@ static inline struct obj_cgroup **page_objcgs_check(struct page *page) { unsigned long memcg_data = READ_ONCE(page->memcg_data); - if (memcg_data && (memcg_data & 0x1UL)) - return (struct obj_cgroup **)(memcg_data & ~0x1UL); + if (!memcg_data || !(memcg_data & MEMCG_DATA_OBJCGS)) + return NULL; - return NULL; + return (struct obj_cgroup **)(memcg_data & ~MEMCG_DATA_FLAGS_MASK); } /* @@ -460,7 +467,8 @@ static inline struct obj_cgroup **page_objcgs_check(struct page *page) static inline bool set_page_objcgs(struct page *page, struct obj_cgroup **objcgs) { - return !cmpxchg(&page->memcg_data, 0, (unsigned long)objcgs | 0x1UL); + return !cmpxchg(&page->memcg_data, 0, (unsigned long)objcgs | + MEMCG_DATA_OBJCGS); } #else static inline struct obj_cgroup **page_objcgs(struct page *page) -- cgit v1.3-14-g43fede From 18b2db3b0385226b71cb3288474fa5a6e4a45474 Mon Sep 17 00:00:00 2001 From: Roman Gushchin Date: Tue, 1 Dec 2020 13:58:30 -0800 Subject: mm: Convert page kmemcg type to a page memcg flag PageKmemcg flag is currently defined as a page type (like buddy, offline, table and guard). Semantically it means that the page was accounted as a kernel memory by the page allocator and has to be uncharged on the release. As a side effect of defining the flag as a page type, the accounted page can't be mapped to userspace (look at page_has_type() and comments above). In particular, this blocks the accounting of vmalloc-backed memory used by some bpf maps, because these maps do map the memory to userspace. One option is to fix it by complicating the access to page->mapcount, which provides some free bits for page->page_type. But it's way better to move this flag into page->memcg_data flags. Indeed, the flag makes no sense without enabled memory cgroups and memory cgroup pointer set in particular. This commit replaces PageKmemcg() and __SetPageKmemcg() with PageMemcgKmem() and an open-coded OR operation setting the memcg pointer with the MEMCG_DATA_KMEM bit. __ClearPageKmemcg() can be simple deleted, as the whole memcg_data is zeroed at once. As a bonus, on !CONFIG_MEMCG build the PageMemcgKmem() check will be compiled out. Signed-off-by: Roman Gushchin Signed-off-by: Andrew Morton Signed-off-by: Alexei Starovoitov Reviewed-by: Shakeel Butt Acked-by: Johannes Weiner Acked-by: Michal Hocko Link: https://lkml.kernel.org/r/20201027001657.3398190-5-guro@fb.com Link: https://lore.kernel.org/bpf/20201201215900.3569844-5-guro@fb.com --- include/linux/memcontrol.h | 37 +++++++++++++++++++++++++++++++++---- include/linux/page-flags.h | 11 ++--------- mm/memcontrol.c | 16 +++++----------- mm/page_alloc.c | 4 ++-- 4 files changed, 42 insertions(+), 26 deletions(-) (limited to 'include/linux/memcontrol.h') diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h index 99a4841d658b..7c9d43476166 100644 --- a/include/linux/memcontrol.h +++ b/include/linux/memcontrol.h @@ -346,8 +346,10 @@ extern struct mem_cgroup *root_mem_cgroup; enum page_memcg_data_flags { /* page->memcg_data is a pointer to an objcgs vector */ MEMCG_DATA_OBJCGS = (1UL << 0), + /* page has been accounted as a non-slab kernel page */ + MEMCG_DATA_KMEM = (1UL << 1), /* the next bit after the last actual flag */ - __NR_MEMCG_DATA_FLAGS = (1UL << 1), + __NR_MEMCG_DATA_FLAGS = (1UL << 2), }; #define MEMCG_DATA_FLAGS_MASK (__NR_MEMCG_DATA_FLAGS - 1) @@ -369,8 +371,12 @@ enum page_memcg_data_flags { */ static inline struct mem_cgroup *page_memcg(struct page *page) { + unsigned long memcg_data = page->memcg_data; + VM_BUG_ON_PAGE(PageSlab(page), page); - return (struct mem_cgroup *)page->memcg_data; + VM_BUG_ON_PAGE(memcg_data & MEMCG_DATA_OBJCGS, page); + + return (struct mem_cgroup *)(memcg_data & ~MEMCG_DATA_FLAGS_MASK); } /* @@ -387,7 +393,8 @@ static inline struct mem_cgroup *page_memcg_rcu(struct page *page) VM_BUG_ON_PAGE(PageSlab(page), page); WARN_ON_ONCE(!rcu_read_lock_held()); - return (struct mem_cgroup *)READ_ONCE(page->memcg_data); + return (struct mem_cgroup *)(READ_ONCE(page->memcg_data) & + ~MEMCG_DATA_FLAGS_MASK); } /* @@ -416,7 +423,21 @@ static inline struct mem_cgroup *page_memcg_check(struct page *page) if (memcg_data & MEMCG_DATA_OBJCGS) return NULL; - return (struct mem_cgroup *)memcg_data; + return (struct mem_cgroup *)(memcg_data & ~MEMCG_DATA_FLAGS_MASK); +} + +/* + * PageMemcgKmem - check if the page has MemcgKmem flag set + * @page: a pointer to the page struct + * + * Checks if the page has MemcgKmem flag set. The caller must ensure that + * the page has an associated memory cgroup. It's not safe to call this function + * against some types of pages, e.g. slab pages. + */ +static inline bool PageMemcgKmem(struct page *page) +{ + VM_BUG_ON_PAGE(page->memcg_data & MEMCG_DATA_OBJCGS, page); + return page->memcg_data & MEMCG_DATA_KMEM; } #ifdef CONFIG_MEMCG_KMEM @@ -435,6 +456,7 @@ static inline struct obj_cgroup **page_objcgs(struct page *page) unsigned long memcg_data = READ_ONCE(page->memcg_data); VM_BUG_ON_PAGE(memcg_data && !(memcg_data & MEMCG_DATA_OBJCGS), page); + VM_BUG_ON_PAGE(memcg_data & MEMCG_DATA_KMEM, page); return (struct obj_cgroup **)(memcg_data & ~MEMCG_DATA_FLAGS_MASK); } @@ -454,6 +476,8 @@ static inline struct obj_cgroup **page_objcgs_check(struct page *page) if (!memcg_data || !(memcg_data & MEMCG_DATA_OBJCGS)) return NULL; + VM_BUG_ON_PAGE(memcg_data & MEMCG_DATA_KMEM, page); + return (struct obj_cgroup **)(memcg_data & ~MEMCG_DATA_FLAGS_MASK); } @@ -1109,6 +1133,11 @@ static inline struct mem_cgroup *page_memcg_check(struct page *page) return NULL; } +static inline bool PageMemcgKmem(struct page *page) +{ + return false; +} + static inline bool mem_cgroup_is_root(struct mem_cgroup *memcg) { return true; diff --git a/include/linux/page-flags.h b/include/linux/page-flags.h index 4f6ba9379112..fc0e1bd48e73 100644 --- a/include/linux/page-flags.h +++ b/include/linux/page-flags.h @@ -715,9 +715,8 @@ PAGEFLAG_FALSE(DoubleMap) #define PAGE_MAPCOUNT_RESERVE -128 #define PG_buddy 0x00000080 #define PG_offline 0x00000100 -#define PG_kmemcg 0x00000200 -#define PG_table 0x00000400 -#define PG_guard 0x00000800 +#define PG_table 0x00000200 +#define PG_guard 0x00000400 #define PageType(page, flag) \ ((page->page_type & (PAGE_TYPE_BASE | flag)) == PAGE_TYPE_BASE) @@ -768,12 +767,6 @@ PAGE_TYPE_OPS(Buddy, buddy) */ PAGE_TYPE_OPS(Offline, offline) -/* - * If kmemcg is enabled, the buddy allocator will set PageKmemcg() on - * pages allocated with __GFP_ACCOUNT. It gets cleared on page free. - */ -PAGE_TYPE_OPS(Kmemcg, kmemcg) - /* * Marks pages in use as page tables. */ diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 0054b4846770..e0366e306221 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -3090,8 +3090,8 @@ int __memcg_kmem_charge_page(struct page *page, gfp_t gfp, int order) if (memcg && !mem_cgroup_is_root(memcg)) { ret = __memcg_kmem_charge(memcg, gfp, 1 << order); if (!ret) { - page->memcg_data = (unsigned long)memcg; - __SetPageKmemcg(page); + page->memcg_data = (unsigned long)memcg | + MEMCG_DATA_KMEM; return 0; } css_put(&memcg->css); @@ -3116,10 +3116,6 @@ void __memcg_kmem_uncharge_page(struct page *page, int order) __memcg_kmem_uncharge(memcg, nr_pages); page->memcg_data = 0; css_put(&memcg->css); - - /* slab pages do not have PageKmemcg flag set */ - if (PageKmemcg(page)) - __ClearPageKmemcg(page); } static bool consume_obj_stock(struct obj_cgroup *objcg, unsigned int nr_bytes) @@ -6877,12 +6873,10 @@ static void uncharge_page(struct page *page, struct uncharge_gather *ug) nr_pages = compound_nr(page); ug->nr_pages += nr_pages; - if (!PageKmemcg(page)) { - ug->pgpgout++; - } else { + if (PageMemcgKmem(page)) ug->nr_kmem += nr_pages; - __ClearPageKmemcg(page); - } + else + ug->pgpgout++; ug->dummy_page = page; page->memcg_data = 0; diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 271133b8243b..3c53018c9c61 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -1214,7 +1214,7 @@ static __always_inline bool free_pages_prepare(struct page *page, * Do not let hwpoison pages hit pcplists/buddy * Untie memcg state and reset page's owner */ - if (memcg_kmem_enabled() && PageKmemcg(page)) + if (memcg_kmem_enabled() && PageMemcgKmem(page)) __memcg_kmem_uncharge_page(page, order); reset_page_owner(page, order); return false; @@ -1244,7 +1244,7 @@ static __always_inline bool free_pages_prepare(struct page *page, } if (PageMappingFlags(page)) page->mapping = NULL; - if (memcg_kmem_enabled() && PageKmemcg(page)) + if (memcg_kmem_enabled() && PageMemcgKmem(page)) __memcg_kmem_uncharge_page(page, order); if (check_free) bad += check_free_page(page); -- cgit v1.3-14-g43fede From 1a984c4e8200e0e58bb316f14a4bebb28d32d15a Mon Sep 17 00:00:00 2001 From: Muchun Song Date: Mon, 14 Dec 2020 19:06:24 -0800 Subject: mm: memcontrol: remove unused mod_memcg_obj_state() Since commit 991e7673859e ("mm: memcontrol: account kernel stack per node") there is no user of the mod_memcg_obj_state(). So just remove it. Also rework type of the idx parameter of the mod_objcg_state() from int to enum node_stat_item. Link: https://lkml.kernel.org/r/20201013153504.92602-1-songmuchun@bytedance.com Signed-off-by: Muchun Song Acked-by: Roman Gushchin Acked-by: David Rientjes Reviewed-by: Shakeel Butt Cc: Johannes Weiner Cc: Michal Hocko Cc: Vladimir Davydov Cc: Christopher Lameter Cc: Pekka Enberg Cc: Joonsoo Kim Cc: Vlastimil Babka Cc: Yafang Shao Cc: Chris Down Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/memcontrol.h | 6 ------ mm/memcontrol.c | 11 ----------- mm/slab.h | 4 ++-- 3 files changed, 2 insertions(+), 19 deletions(-) (limited to 'include/linux/memcontrol.h') diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h index 922a7f600465..28bf65560084 100644 --- a/include/linux/memcontrol.h +++ b/include/linux/memcontrol.h @@ -798,8 +798,6 @@ void __mod_lruvec_state(struct lruvec *lruvec, enum node_stat_item idx, int val); void __mod_lruvec_slab_state(void *p, enum node_stat_item idx, int val); -void mod_memcg_obj_state(void *p, int idx, int val); - static inline void mod_lruvec_slab_state(void *p, enum node_stat_item idx, int val) { @@ -1255,10 +1253,6 @@ static inline void mod_lruvec_slab_state(void *p, enum node_stat_item idx, mod_node_page_state(page_pgdat(page), idx, val); } -static inline void mod_memcg_obj_state(void *p, int idx, int val) -{ -} - static inline unsigned long mem_cgroup_soft_limit_reclaim(pg_data_t *pgdat, int order, gfp_t gfp_mask, diff --git a/mm/memcontrol.c b/mm/memcontrol.c index c3654510fb70..83f2e5f84bdc 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -882,17 +882,6 @@ void __mod_lruvec_slab_state(void *p, enum node_stat_item idx, int val) rcu_read_unlock(); } -void mod_memcg_obj_state(void *p, int idx, int val) -{ - struct mem_cgroup *memcg; - - rcu_read_lock(); - memcg = mem_cgroup_from_obj(p); - if (memcg) - mod_memcg_state(memcg, idx, val); - rcu_read_unlock(); -} - /** * __count_memcg_events - account VM events in a cgroup * @memcg: the memory cgroup diff --git a/mm/slab.h b/mm/slab.h index f9977d6613d6..65f4647f1286 100644 --- a/mm/slab.h +++ b/mm/slab.h @@ -204,7 +204,7 @@ ssize_t slabinfo_write(struct file *file, const char __user *buffer, void __kmem_cache_free_bulk(struct kmem_cache *, size_t, void **); int __kmem_cache_alloc_bulk(struct kmem_cache *, gfp_t, size_t, void **); -static inline int cache_vmstat_idx(struct kmem_cache *s) +static inline enum node_stat_item cache_vmstat_idx(struct kmem_cache *s) { return (s->flags & SLAB_RECLAIM_ACCOUNT) ? NR_SLAB_RECLAIMABLE_B : NR_SLAB_UNRECLAIMABLE_B; @@ -304,7 +304,7 @@ static inline bool memcg_slab_pre_alloc_hook(struct kmem_cache *s, static inline void mod_objcg_state(struct obj_cgroup *objcg, struct pglist_data *pgdat, - int idx, int nr) + enum node_stat_item idx, int nr) { struct mem_cgroup *memcg; struct lruvec *lruvec; -- cgit v1.3-14-g43fede From a7cb874bfff785d39de6cc847673539cb3540821 Mon Sep 17 00:00:00 2001 From: Roman Gushchin Date: Mon, 14 Dec 2020 19:06:45 -0800 Subject: mm: memcg: fix obsolete code comments This patch fixes/removes some obsolete comments in the code related to the kernel memory accounting: - kmem_cache->memcg_params.memcg_caches has been removed by commit 9855609bde03 ("mm: memcg/slab: use a single set of kmem_caches for all accounted allocations") - memcg->kmemcg_id is not used as a gate for kmem accounting since commit 0b8f73e10428 ("mm: memcontrol: clean up alloc, online, offline, free functions") Link: https://lkml.kernel.org/r/20201110184615.311974-1-guro@fb.com Signed-off-by: Roman Gushchin Acked-by: Johannes Weiner Reviewed-by: Shakeel Butt Cc: Michal Hocko Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/memcontrol.h | 6 ++---- mm/memcontrol.c | 6 ------ 2 files changed, 2 insertions(+), 10 deletions(-) (limited to 'include/linux/memcontrol.h') diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h index 28bf65560084..1f0f64fa3ccd 100644 --- a/include/linux/memcontrol.h +++ b/include/linux/memcontrol.h @@ -296,7 +296,6 @@ struct mem_cgroup { int tcpmem_pressure; #ifdef CONFIG_MEMCG_KMEM - /* Index in the kmem_cache->memcg_params.memcg_caches array */ int kmemcg_id; enum memcg_kmem_state kmem_state; struct obj_cgroup __rcu *objcg; @@ -1562,9 +1561,8 @@ static inline void memcg_kmem_uncharge(struct mem_cgroup *memcg, } /* - * helper for accessing a memcg's index. It will be used as an index in the - * child cache array in kmem_cache, and also to derive its name. This function - * will return -1 when this is not a kmem-limited memcg. + * A helper for accessing memcg's kmem_id, used for getting + * corresponding LRU lists. */ static inline int memcg_cache_id(struct mem_cgroup *memcg) { diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 758613277286..466d9aed6cc8 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -3703,12 +3703,6 @@ static int memcg_online_kmem(struct mem_cgroup *memcg) static_branch_enable(&memcg_kmem_enabled_key); - /* - * A memory cgroup is considered kmem-online as soon as it gets - * kmemcg_id. Setting the id after enabling static branching will - * guarantee no one starts accounting before all call sites are - * patched. - */ memcg->kmemcg_id = memcg_id; memcg->kmem_state = KMEM_ONLINE; -- cgit v1.3-14-g43fede From bef8620cd8e0a117c1a0719604052e424eb418f9 Mon Sep 17 00:00:00 2001 From: Roman Gushchin Date: Mon, 14 Dec 2020 19:06:49 -0800 Subject: mm: memcg: deprecate the non-hierarchical mode Patch series "mm: memcg: deprecate cgroup v1 non-hierarchical mode", v1. The non-hierarchical cgroup v1 mode is a legacy of early days of the memory controller and doesn't bring any value today. However, it complicates the code and creates many edge cases all over the memory controller code. It's a good time to deprecate it completely. This patchset removes the internal logic, adjusts the user interface and updates the documentation. The alt patch removes some bits of the cgroup core code, which become obsolete. Michal Hocko said: "All that we know today is that we have a warning in place to complain loudly when somebody relies on use_hierarchy=0 with a deeper hierarchy. For all those years we have seen _zero_ reports that would describe a sensible usecase. Moreover we (SUSE) have backported this warning into old distribution kernels (since 3.0 based kernels) to extend the coverage and didn't hear even for users who adopt new kernels only very slowly. The only report we have seen so far was a LTP test suite which doesn't really reflect any real life usecase" This patch (of 3): The non-hierarchical cgroup v1 mode is a legacy of early days of the memory controller and doesn't bring any value today. However, it complicates the code and creates many edge cases all over the memory controller code. It's a good time to deprecate it completely. Functionally this patch enabled is by default for all cgroups and forbids switching it off. Nothing changes if cgroup v2 is used: hierarchical mode was enforced from scratch. To protect the ABI memory.use_hierarchy interface is preserved with a limited functionality: reading always returns "1", writing of "1" passes silently, writing of any other value fails with -EINVAL and a warning to dmesg (on the first occasion). Link: https://lkml.kernel.org/r/20201110220800.929549-1-guro@fb.com Link: https://lkml.kernel.org/r/20201110220800.929549-2-guro@fb.com Signed-off-by: Roman Gushchin Acked-by: Michal Hocko Reviewed-by: Shakeel Butt Acked-by: David Rientjes Acked-by: Johannes Weiner Cc: Tejun Heo Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/memcontrol.h | 7 ---- kernel/cgroup/cgroup.c | 5 --- mm/memcontrol.c | 90 +++++++--------------------------------------- 3 files changed, 13 insertions(+), 89 deletions(-) (limited to 'include/linux/memcontrol.h') diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h index 1f0f64fa3ccd..dd992b81bcb7 100644 --- a/include/linux/memcontrol.h +++ b/include/linux/memcontrol.h @@ -234,11 +234,6 @@ struct mem_cgroup { /* vmpressure notifications */ struct vmpressure vmpressure; - /* - * Should the accounting and control be hierarchical, per subtree? - */ - bool use_hierarchy; - /* * Should the OOM killer kill all belonging tasks, had it kill one? */ @@ -588,8 +583,6 @@ static inline bool mem_cgroup_is_descendant(struct mem_cgroup *memcg, { if (root == memcg) return true; - if (!root->use_hierarchy) - return false; return cgroup_is_descendant(memcg->css.cgroup, root->css.cgroup); } diff --git a/kernel/cgroup/cgroup.c b/kernel/cgroup/cgroup.c index e41c21819ba0..80c5c34416e8 100644 --- a/kernel/cgroup/cgroup.c +++ b/kernel/cgroup/cgroup.c @@ -281,9 +281,6 @@ bool cgroup_ssid_enabled(int ssid) * - cpuset: a task can be moved into an empty cpuset, and again it takes * masks of ancestors. * - * - memcg: use_hierarchy is on by default and the cgroup file for the flag - * is not created. - * * - blkcg: blk-throttle becomes properly hierarchical. * * - debug: disallowed on the default hierarchy. @@ -5156,8 +5153,6 @@ static struct cgroup_subsys_state *css_create(struct cgroup *cgrp, cgroup_parent(parent)) { pr_warn("%s (%d) created nested cgroup for controller \"%s\" which has incomplete hierarchy support. Nested cgroups may change behavior in the future.\n", current->comm, current->pid, ss->name); - if (!strcmp(ss->name, "memory")) - pr_warn("\"memory\" requires setting use_hierarchy to 1 on the root\n"); ss->warned_broken_hierarchy = true; } diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 466d9aed6cc8..fc18a2b7d25a 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -1141,12 +1141,6 @@ struct mem_cgroup *mem_cgroup_iter(struct mem_cgroup *root, if (prev && !reclaim) pos = prev; - if (!root->use_hierarchy && root != root_mem_cgroup) { - if (prev) - goto out; - return root; - } - rcu_read_lock(); if (reclaim) { @@ -1226,7 +1220,6 @@ struct mem_cgroup *mem_cgroup_iter(struct mem_cgroup *root, out_unlock: rcu_read_unlock(); -out: if (prev && prev != root) css_put(&prev->css); @@ -3461,10 +3454,7 @@ unsigned long mem_cgroup_soft_limit_reclaim(pg_data_t *pgdat, int order, } /* - * Test whether @memcg has children, dead or alive. Note that this - * function doesn't care whether @memcg has use_hierarchy enabled and - * returns %true if there are child csses according to the cgroup - * hierarchy. Testing use_hierarchy is the caller's responsibility. + * Test whether @memcg has children, dead or alive. */ static inline bool memcg_has_children(struct mem_cgroup *memcg) { @@ -3524,37 +3514,20 @@ static ssize_t mem_cgroup_force_empty_write(struct kernfs_open_file *of, static u64 mem_cgroup_hierarchy_read(struct cgroup_subsys_state *css, struct cftype *cft) { - return mem_cgroup_from_css(css)->use_hierarchy; + return 1; } static int mem_cgroup_hierarchy_write(struct cgroup_subsys_state *css, struct cftype *cft, u64 val) { - int retval = 0; - struct mem_cgroup *memcg = mem_cgroup_from_css(css); - struct mem_cgroup *parent_memcg = mem_cgroup_from_css(memcg->css.parent); - - if (memcg->use_hierarchy == val) + if (val == 1) return 0; - /* - * If parent's use_hierarchy is set, we can't make any modifications - * in the child subtrees. If it is unset, then the change can - * occur, provided the current cgroup has no children. - * - * For the root cgroup, parent_mem is NULL, we allow value to be - * set if there are no children. - */ - if ((!parent_memcg || !parent_memcg->use_hierarchy) && - (val == 1 || val == 0)) { - if (!memcg_has_children(memcg)) - memcg->use_hierarchy = val; - else - retval = -EBUSY; - } else - retval = -EINVAL; + pr_warn_once("Non-hierarchical mode is deprecated. " + "Please report your usecase to linux-mm@kvack.org if you " + "depend on this functionality.\n"); - return retval; + return -EINVAL; } static unsigned long mem_cgroup_usage(struct mem_cgroup *memcg, bool swap) @@ -3742,8 +3715,6 @@ static void memcg_offline_kmem(struct mem_cgroup *memcg) child = mem_cgroup_from_css(css); BUG_ON(child->kmemcg_id != kmemcg_id); child->kmemcg_id = parent->kmemcg_id; - if (!memcg->use_hierarchy) - break; } rcu_read_unlock(); @@ -5334,38 +5305,22 @@ mem_cgroup_css_alloc(struct cgroup_subsys_state *parent_css) if (parent) { memcg->swappiness = mem_cgroup_swappiness(parent); memcg->oom_kill_disable = parent->oom_kill_disable; - } - if (!parent) { - page_counter_init(&memcg->memory, NULL); - page_counter_init(&memcg->swap, NULL); - page_counter_init(&memcg->kmem, NULL); - page_counter_init(&memcg->tcpmem, NULL); - } else if (parent->use_hierarchy) { - memcg->use_hierarchy = true; + page_counter_init(&memcg->memory, &parent->memory); page_counter_init(&memcg->swap, &parent->swap); page_counter_init(&memcg->kmem, &parent->kmem); page_counter_init(&memcg->tcpmem, &parent->tcpmem); } else { - page_counter_init(&memcg->memory, &root_mem_cgroup->memory); - page_counter_init(&memcg->swap, &root_mem_cgroup->swap); - page_counter_init(&memcg->kmem, &root_mem_cgroup->kmem); - page_counter_init(&memcg->tcpmem, &root_mem_cgroup->tcpmem); - /* - * Deeper hierachy with use_hierarchy == false doesn't make - * much sense so let cgroup subsystem know about this - * unfortunate state in our controller. - */ - if (parent != root_mem_cgroup) - memory_cgrp_subsys.broken_hierarchy = true; - } + page_counter_init(&memcg->memory, NULL); + page_counter_init(&memcg->swap, NULL); + page_counter_init(&memcg->kmem, NULL); + page_counter_init(&memcg->tcpmem, NULL); - /* The following stuff does not apply to the root */ - if (!parent) { root_mem_cgroup = memcg; return &memcg->css; } + /* The following stuff does not apply to the root */ error = memcg_online_kmem(memcg); if (error) goto fail; @@ -6202,24 +6157,6 @@ static void mem_cgroup_move_task(void) } #endif -/* - * Cgroup retains root cgroups across [un]mount cycles making it necessary - * to verify whether we're attached to the default hierarchy on each mount - * attempt. - */ -static void mem_cgroup_bind(struct cgroup_subsys_state *root_css) -{ - /* - * use_hierarchy is forced on the default hierarchy. cgroup core - * guarantees that @root doesn't have any children, so turning it - * on for the root memcg is enough. - */ - if (cgroup_subsys_on_dfl(memory_cgrp_subsys)) - root_mem_cgroup->use_hierarchy = true; - else - root_mem_cgroup->use_hierarchy = false; -} - static int seq_puts_memcg_tunable(struct seq_file *m, unsigned long value) { if (value == PAGE_COUNTER_MAX) @@ -6557,7 +6494,6 @@ struct cgroup_subsys memory_cgrp_subsys = { .can_attach = mem_cgroup_can_attach, .cancel_attach = mem_cgroup_cancel_attach, .post_attach = mem_cgroup_move_task, - .bind = mem_cgroup_bind, .dfl_cftypes = memory_files, .legacy_cftypes = mem_cgroup_legacy_files, .early_init = 0, -- cgit v1.3-14-g43fede From da3ceeff923e3bc750a8423c840462760c463926 Mon Sep 17 00:00:00 2001 From: Muchun Song Date: Mon, 14 Dec 2020 19:07:04 -0800 Subject: mm: memcg/slab: rename *_lruvec_slab_state to *_lruvec_kmem_state The *_lruvec_slab_state is also suitable for pages allocated from buddy, not just for the slab objects. But the function name seems to tell us that only slab object is applicable. So we can rename the keyword of slab to kmem. Link: https://lkml.kernel.org/r/20201117085249.24319-1-songmuchun@bytedance.com Signed-off-by: Muchun Song Acked-by: Roman Gushchin Reviewed-by: Shakeel Butt Acked-by: Johannes Weiner Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/memcontrol.h | 18 +++++++++--------- kernel/fork.c | 2 +- mm/memcontrol.c | 2 +- mm/workingset.c | 8 ++++---- 4 files changed, 15 insertions(+), 15 deletions(-) (limited to 'include/linux/memcontrol.h') diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h index dd992b81bcb7..71c961452d9a 100644 --- a/include/linux/memcontrol.h +++ b/include/linux/memcontrol.h @@ -788,15 +788,15 @@ void __mod_memcg_lruvec_state(struct lruvec *lruvec, enum node_stat_item idx, int val); void __mod_lruvec_state(struct lruvec *lruvec, enum node_stat_item idx, int val); -void __mod_lruvec_slab_state(void *p, enum node_stat_item idx, int val); +void __mod_lruvec_kmem_state(void *p, enum node_stat_item idx, int val); -static inline void mod_lruvec_slab_state(void *p, enum node_stat_item idx, +static inline void mod_lruvec_kmem_state(void *p, enum node_stat_item idx, int val) { unsigned long flags; local_irq_save(flags); - __mod_lruvec_slab_state(p, idx, val); + __mod_lruvec_kmem_state(p, idx, val); local_irq_restore(flags); } @@ -1229,7 +1229,7 @@ static inline void mod_lruvec_page_state(struct page *page, mod_node_page_state(page_pgdat(page), idx, val); } -static inline void __mod_lruvec_slab_state(void *p, enum node_stat_item idx, +static inline void __mod_lruvec_kmem_state(void *p, enum node_stat_item idx, int val) { struct page *page = virt_to_head_page(p); @@ -1237,7 +1237,7 @@ static inline void __mod_lruvec_slab_state(void *p, enum node_stat_item idx, __mod_node_page_state(page_pgdat(page), idx, val); } -static inline void mod_lruvec_slab_state(void *p, enum node_stat_item idx, +static inline void mod_lruvec_kmem_state(void *p, enum node_stat_item idx, int val) { struct page *page = virt_to_head_page(p); @@ -1332,14 +1332,14 @@ static inline void __dec_lruvec_page_state(struct page *page, __mod_lruvec_page_state(page, idx, -1); } -static inline void __inc_lruvec_slab_state(void *p, enum node_stat_item idx) +static inline void __inc_lruvec_kmem_state(void *p, enum node_stat_item idx) { - __mod_lruvec_slab_state(p, idx, 1); + __mod_lruvec_kmem_state(p, idx, 1); } -static inline void __dec_lruvec_slab_state(void *p, enum node_stat_item idx) +static inline void __dec_lruvec_kmem_state(void *p, enum node_stat_item idx) { - __mod_lruvec_slab_state(p, idx, -1); + __mod_lruvec_kmem_state(p, idx, -1); } /* idx can be of type enum memcg_stat_item or node_stat_item */ diff --git a/kernel/fork.c b/kernel/fork.c index dc55f68a6ee3..5e7cc88eadb5 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -385,7 +385,7 @@ static void account_kernel_stack(struct task_struct *tsk, int account) mod_lruvec_page_state(vm->pages[0], NR_KERNEL_STACK_KB, account * (THREAD_SIZE / 1024)); else - mod_lruvec_slab_state(stack, NR_KERNEL_STACK_KB, + mod_lruvec_kmem_state(stack, NR_KERNEL_STACK_KB, account * (THREAD_SIZE / 1024)); } diff --git a/mm/memcontrol.c b/mm/memcontrol.c index ce19e8484c89..b50f7f336b16 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -853,7 +853,7 @@ void __mod_lruvec_state(struct lruvec *lruvec, enum node_stat_item idx, __mod_memcg_lruvec_state(lruvec, idx, val); } -void __mod_lruvec_slab_state(void *p, enum node_stat_item idx, int val) +void __mod_lruvec_kmem_state(void *p, enum node_stat_item idx, int val) { pg_data_t *pgdat = page_pgdat(virt_to_page(p)); struct mem_cgroup *memcg; diff --git a/mm/workingset.c b/mm/workingset.c index 975a4d2dd02e..25f75bbe80e0 100644 --- a/mm/workingset.c +++ b/mm/workingset.c @@ -445,12 +445,12 @@ void workingset_update_node(struct xa_node *node) if (node->count && node->count == node->nr_values) { if (list_empty(&node->private_list)) { list_lru_add(&shadow_nodes, &node->private_list); - __inc_lruvec_slab_state(node, WORKINGSET_NODES); + __inc_lruvec_kmem_state(node, WORKINGSET_NODES); } } else { if (!list_empty(&node->private_list)) { list_lru_del(&shadow_nodes, &node->private_list); - __dec_lruvec_slab_state(node, WORKINGSET_NODES); + __dec_lruvec_kmem_state(node, WORKINGSET_NODES); } } } @@ -544,7 +544,7 @@ static enum lru_status shadow_lru_isolate(struct list_head *item, } list_lru_isolate(lru, item); - __dec_lruvec_slab_state(node, WORKINGSET_NODES); + __dec_lruvec_kmem_state(node, WORKINGSET_NODES); spin_unlock(lru_lock); @@ -559,7 +559,7 @@ static enum lru_status shadow_lru_isolate(struct list_head *item, goto out_invalid; mapping->nrexceptional -= node->nr_values; xa_delete_node(node, workingset_update_node); - __inc_lruvec_slab_state(node, WORKINGSET_NODERECLAIM); + __inc_lruvec_kmem_state(node, WORKINGSET_NODERECLAIM); out_invalid: xa_unlock_irq(&mapping->i_pages); -- cgit v1.3-14-g43fede From c47d5032ed3002311a4188eae51f4641ec436beb Mon Sep 17 00:00:00 2001 From: Shakeel Butt Date: Mon, 14 Dec 2020 19:07:14 -0800 Subject: mm: move lruvec stats update functions to vmstat.h Patch series "memcg: add pagetable comsumption to memory.stat", v2. Many workloads consumes significant amount of memory in pagetables. One specific use-case is the user space network driver which mmaps the application memory to provide zero copy transfer. This driver can consume a large amount memory in page tables. This patch series exposes the pagetable comsumption for each memory cgroup. This patch (of 2): This does not change any functionality and only move the functions which update the lruvec stats to vmstat.h from memcontrol.h. The main reason for this patch is to be able to use these functions in the page table contructor function which is defined in mm.h and we can not include the memcontrol.h in that file. Also this is a better place for this interface in general. The lruvec abstraction, while invented for memcg, isn't specific to memcg at all. Link: https://lkml.kernel.org/r/20201130212541.2781790-2-shakeelb@google.com Signed-off-by: Shakeel Butt Acked-by: Johannes Weiner Acked-by: Roman Gushchin Cc: Michal Hocko Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/memcontrol.h | 111 --------------------------------------------- include/linux/vmstat.h | 104 ++++++++++++++++++++++++++++++++++++++++++ mm/memcontrol.c | 17 +++++++ 3 files changed, 121 insertions(+), 111 deletions(-) (limited to 'include/linux/memcontrol.h') diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h index 71c961452d9a..f530d634f055 100644 --- a/include/linux/memcontrol.h +++ b/include/linux/memcontrol.h @@ -786,8 +786,6 @@ static inline unsigned long lruvec_page_state_local(struct lruvec *lruvec, void __mod_memcg_lruvec_state(struct lruvec *lruvec, enum node_stat_item idx, int val); -void __mod_lruvec_state(struct lruvec *lruvec, enum node_stat_item idx, - int val); void __mod_lruvec_kmem_state(void *p, enum node_stat_item idx, int val); static inline void mod_lruvec_kmem_state(void *p, enum node_stat_item idx, @@ -810,43 +808,6 @@ static inline void mod_memcg_lruvec_state(struct lruvec *lruvec, local_irq_restore(flags); } -static inline void mod_lruvec_state(struct lruvec *lruvec, - enum node_stat_item idx, int val) -{ - unsigned long flags; - - local_irq_save(flags); - __mod_lruvec_state(lruvec, idx, val); - local_irq_restore(flags); -} - -static inline void __mod_lruvec_page_state(struct page *page, - enum node_stat_item idx, int val) -{ - struct page *head = compound_head(page); /* rmap on tail pages */ - pg_data_t *pgdat = page_pgdat(page); - struct lruvec *lruvec; - - /* Untracked pages have no memcg, no lruvec. Update only the node */ - if (!head->mem_cgroup) { - __mod_node_page_state(pgdat, idx, val); - return; - } - - lruvec = mem_cgroup_lruvec(head->mem_cgroup, pgdat); - __mod_lruvec_state(lruvec, idx, val); -} - -static inline void mod_lruvec_page_state(struct page *page, - enum node_stat_item idx, int val) -{ - unsigned long flags; - - local_irq_save(flags); - __mod_lruvec_page_state(page, idx, val); - local_irq_restore(flags); -} - unsigned long mem_cgroup_soft_limit_reclaim(pg_data_t *pgdat, int order, gfp_t gfp_mask, unsigned long *total_scanned); @@ -1205,30 +1166,6 @@ static inline void __mod_memcg_lruvec_state(struct lruvec *lruvec, { } -static inline void __mod_lruvec_state(struct lruvec *lruvec, - enum node_stat_item idx, int val) -{ - __mod_node_page_state(lruvec_pgdat(lruvec), idx, val); -} - -static inline void mod_lruvec_state(struct lruvec *lruvec, - enum node_stat_item idx, int val) -{ - mod_node_page_state(lruvec_pgdat(lruvec), idx, val); -} - -static inline void __mod_lruvec_page_state(struct page *page, - enum node_stat_item idx, int val) -{ - __mod_node_page_state(page_pgdat(page), idx, val); -} - -static inline void mod_lruvec_page_state(struct page *page, - enum node_stat_item idx, int val) -{ - mod_node_page_state(page_pgdat(page), idx, val); -} - static inline void __mod_lruvec_kmem_state(void *p, enum node_stat_item idx, int val) { @@ -1308,30 +1245,6 @@ static inline void __dec_memcg_page_state(struct page *page, __mod_memcg_page_state(page, idx, -1); } -static inline void __inc_lruvec_state(struct lruvec *lruvec, - enum node_stat_item idx) -{ - __mod_lruvec_state(lruvec, idx, 1); -} - -static inline void __dec_lruvec_state(struct lruvec *lruvec, - enum node_stat_item idx) -{ - __mod_lruvec_state(lruvec, idx, -1); -} - -static inline void __inc_lruvec_page_state(struct page *page, - enum node_stat_item idx) -{ - __mod_lruvec_page_state(page, idx, 1); -} - -static inline void __dec_lruvec_page_state(struct page *page, - enum node_stat_item idx) -{ - __mod_lruvec_page_state(page, idx, -1); -} - static inline void __inc_lruvec_kmem_state(void *p, enum node_stat_item idx) { __mod_lruvec_kmem_state(p, idx, 1); @@ -1370,30 +1283,6 @@ static inline void dec_memcg_page_state(struct page *page, mod_memcg_page_state(page, idx, -1); } -static inline void inc_lruvec_state(struct lruvec *lruvec, - enum node_stat_item idx) -{ - mod_lruvec_state(lruvec, idx, 1); -} - -static inline void dec_lruvec_state(struct lruvec *lruvec, - enum node_stat_item idx) -{ - mod_lruvec_state(lruvec, idx, -1); -} - -static inline void inc_lruvec_page_state(struct page *page, - enum node_stat_item idx) -{ - mod_lruvec_page_state(page, idx, 1); -} - -static inline void dec_lruvec_page_state(struct page *page, - enum node_stat_item idx) -{ - mod_lruvec_page_state(page, idx, -1); -} - static inline struct lruvec *parent_lruvec(struct lruvec *lruvec) { struct mem_cgroup *memcg; diff --git a/include/linux/vmstat.h b/include/linux/vmstat.h index 322dcbfcc933..773135fc6e19 100644 --- a/include/linux/vmstat.h +++ b/include/linux/vmstat.h @@ -450,4 +450,108 @@ static inline const char *vm_event_name(enum vm_event_item item) } #endif /* CONFIG_VM_EVENT_COUNTERS || CONFIG_MEMCG */ +#ifdef CONFIG_MEMCG + +void __mod_lruvec_state(struct lruvec *lruvec, enum node_stat_item idx, + int val); + +static inline void mod_lruvec_state(struct lruvec *lruvec, + enum node_stat_item idx, int val) +{ + unsigned long flags; + + local_irq_save(flags); + __mod_lruvec_state(lruvec, idx, val); + local_irq_restore(flags); +} + +void __mod_lruvec_page_state(struct page *page, + enum node_stat_item idx, int val); + +static inline void mod_lruvec_page_state(struct page *page, + enum node_stat_item idx, int val) +{ + unsigned long flags; + + local_irq_save(flags); + __mod_lruvec_page_state(page, idx, val); + local_irq_restore(flags); +} + +#else + +static inline void __mod_lruvec_state(struct lruvec *lruvec, + enum node_stat_item idx, int val) +{ + __mod_node_page_state(lruvec_pgdat(lruvec), idx, val); +} + +static inline void mod_lruvec_state(struct lruvec *lruvec, + enum node_stat_item idx, int val) +{ + mod_node_page_state(lruvec_pgdat(lruvec), idx, val); +} + +static inline void __mod_lruvec_page_state(struct page *page, + enum node_stat_item idx, int val) +{ + __mod_node_page_state(page_pgdat(page), idx, val); +} + +static inline void mod_lruvec_page_state(struct page *page, + enum node_stat_item idx, int val) +{ + mod_node_page_state(page_pgdat(page), idx, val); +} + +#endif /* CONFIG_MEMCG */ + +static inline void __inc_lruvec_state(struct lruvec *lruvec, + enum node_stat_item idx) +{ + __mod_lruvec_state(lruvec, idx, 1); +} + +static inline void __dec_lruvec_state(struct lruvec *lruvec, + enum node_stat_item idx) +{ + __mod_lruvec_state(lruvec, idx, -1); +} + +static inline void __inc_lruvec_page_state(struct page *page, + enum node_stat_item idx) +{ + __mod_lruvec_page_state(page, idx, 1); +} + +static inline void __dec_lruvec_page_state(struct page *page, + enum node_stat_item idx) +{ + __mod_lruvec_page_state(page, idx, -1); +} + +static inline void inc_lruvec_state(struct lruvec *lruvec, + enum node_stat_item idx) +{ + mod_lruvec_state(lruvec, idx, 1); +} + +static inline void dec_lruvec_state(struct lruvec *lruvec, + enum node_stat_item idx) +{ + mod_lruvec_state(lruvec, idx, -1); +} + +static inline void inc_lruvec_page_state(struct page *page, + enum node_stat_item idx) +{ + mod_lruvec_page_state(page, idx, 1); +} + +static inline void dec_lruvec_page_state(struct page *page, + enum node_stat_item idx) +{ + mod_lruvec_page_state(page, idx, -1); +} + #endif /* _LINUX_VMSTAT_H */ diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 0083b69b5cac..52837d68bbec 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -853,6 +853,23 @@ void __mod_lruvec_state(struct lruvec *lruvec, enum node_stat_item idx, __mod_memcg_lruvec_state(lruvec, idx, val); } +void __mod_lruvec_page_state(struct page *page, enum node_stat_item idx, + int val) +{ + struct page *head = compound_head(page); /* rmap on tail pages */ + pg_data_t *pgdat = page_pgdat(page); + struct lruvec *lruvec; + + /* Untracked pages have no memcg, no lruvec. Update only the node */ + if (!head->mem_cgroup) { + __mod_node_page_state(pgdat, idx, val); + return; + } + + lruvec = mem_cgroup_lruvec(head->mem_cgroup, pgdat); + __mod_lruvec_state(lruvec, idx, val); +} + void __mod_lruvec_kmem_state(void *p, enum node_stat_item idx, int val) { pg_data_t *pgdat = page_pgdat(virt_to_page(p)); -- cgit v1.3-14-g43fede From 6168d0da2b479ce25a4647de194045de1bdd1f1d Mon Sep 17 00:00:00 2001 From: Alex Shi Date: Tue, 15 Dec 2020 12:34:29 -0800 Subject: mm/lru: replace pgdat lru_lock with lruvec lock MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This patch moves per node lru_lock into lruvec, thus bring a lru_lock for each of memcg per node. So on a large machine, each of memcg don't have to suffer from per node pgdat->lru_lock competition. They could go fast with their self lru_lock. After move memcg charge before lru inserting, page isolation could serialize page's memcg, then per memcg lruvec lock is stable and could replace per node lru lock. In isolate_migratepages_block(), compact_unlock_should_abort and lock_page_lruvec_irqsave are open coded to work with compact_control. Also add a debug func in locking which may give some clues if there are sth out of hands. Daniel Jordan's testing show 62% improvement on modified readtwice case on his 2P * 10 core * 2 HT broadwell box. https://lore.kernel.org/lkml/20200915165807.kpp7uhiw7l3loofu@ca-dmjordan1.us.oracle.com/ Hugh Dickins helped on the patch polish, thanks! [alex.shi@linux.alibaba.com: fix comment typo] Link: https://lkml.kernel.org/r/5b085715-292a-4b43-50b3-d73dc90d1de5@linux.alibaba.com [alex.shi@linux.alibaba.com: use page_memcg()] Link: https://lkml.kernel.org/r/5a4c2b72-7ee8-2478-fc0e-85eb83aafec4@linux.alibaba.com Link: https://lkml.kernel.org/r/1604566549-62481-18-git-send-email-alex.shi@linux.alibaba.com Signed-off-by: Alex Shi Acked-by: Hugh Dickins Acked-by: Johannes Weiner Cc: Rong Chen Cc: Michal Hocko Cc: Vladimir Davydov Cc: Yang Shi Cc: Matthew Wilcox Cc: Konstantin Khlebnikov Cc: Daniel Jordan Cc: Alexander Duyck Cc: Andrea Arcangeli Cc: Andrey Ryabinin Cc: "Huang, Ying" Cc: Jann Horn Cc: Joonsoo Kim Cc: Kirill A. Shutemov Cc: Kirill A. Shutemov Cc: Mel Gorman Cc: Michal Hocko Cc: Mika Penttilä Cc: Minchan Kim Cc: Shakeel Butt Cc: Tejun Heo Cc: Thomas Gleixner Cc: Vlastimil Babka Cc: Wei Yang Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/memcontrol.h | 58 +++++++++++++++++++++++ include/linux/mmzone.h | 3 +- mm/compaction.c | 56 ++++++++++++++-------- mm/huge_memory.c | 11 ++--- mm/memcontrol.c | 78 ++++++++++++++++++++++++++++-- mm/mlock.c | 22 ++++++--- mm/mmzone.c | 1 + mm/page_alloc.c | 1 - mm/swap.c | 116 ++++++++++++++++++++++----------------------- mm/vmscan.c | 55 ++++++++++----------- 10 files changed, 275 insertions(+), 126 deletions(-) (limited to 'include/linux/memcontrol.h') diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h index f530d634f055..aa5d559853c2 100644 --- a/include/linux/memcontrol.h +++ b/include/linux/memcontrol.h @@ -491,6 +491,19 @@ struct mem_cgroup *get_mem_cgroup_from_mm(struct mm_struct *mm); struct mem_cgroup *get_mem_cgroup_from_page(struct page *page); +struct lruvec *lock_page_lruvec(struct page *page); +struct lruvec *lock_page_lruvec_irq(struct page *page); +struct lruvec *lock_page_lruvec_irqsave(struct page *page, + unsigned long *flags); + +#ifdef CONFIG_DEBUG_VM +void lruvec_memcg_debug(struct lruvec *lruvec, struct page *page); +#else +static inline void lruvec_memcg_debug(struct lruvec *lruvec, struct page *page) +{ +} +#endif + static inline struct mem_cgroup *mem_cgroup_from_css(struct cgroup_subsys_state *css){ return css ? container_of(css, struct mem_cgroup, css) : NULL; @@ -996,6 +1009,31 @@ static inline void mem_cgroup_put(struct mem_cgroup *memcg) { } +static inline struct lruvec *lock_page_lruvec(struct page *page) +{ + struct pglist_data *pgdat = page_pgdat(page); + + spin_lock(&pgdat->__lruvec.lru_lock); + return &pgdat->__lruvec; +} + +static inline struct lruvec *lock_page_lruvec_irq(struct page *page) +{ + struct pglist_data *pgdat = page_pgdat(page); + + spin_lock_irq(&pgdat->__lruvec.lru_lock); + return &pgdat->__lruvec; +} + +static inline struct lruvec *lock_page_lruvec_irqsave(struct page *page, + unsigned long *flagsp) +{ + struct pglist_data *pgdat = page_pgdat(page); + + spin_lock_irqsave(&pgdat->__lruvec.lru_lock, *flagsp); + return &pgdat->__lruvec; +} + static inline struct mem_cgroup * mem_cgroup_iter(struct mem_cgroup *root, struct mem_cgroup *prev, @@ -1215,6 +1253,10 @@ static inline void count_memcg_event_mm(struct mm_struct *mm, enum vm_event_item idx) { } + +static inline void lruvec_memcg_debug(struct lruvec *lruvec, struct page *page) +{ +} #endif /* CONFIG_MEMCG */ /* idx can be of type enum memcg_stat_item or node_stat_item */ @@ -1296,6 +1338,22 @@ static inline struct lruvec *parent_lruvec(struct lruvec *lruvec) return mem_cgroup_lruvec(memcg, lruvec_pgdat(lruvec)); } +static inline void unlock_page_lruvec(struct lruvec *lruvec) +{ + spin_unlock(&lruvec->lru_lock); +} + +static inline void unlock_page_lruvec_irq(struct lruvec *lruvec) +{ + spin_unlock_irq(&lruvec->lru_lock); +} + +static inline void unlock_page_lruvec_irqrestore(struct lruvec *lruvec, + unsigned long flags) +{ + spin_unlock_irqrestore(&lruvec->lru_lock, flags); +} + #ifdef CONFIG_CGROUP_WRITEBACK struct wb_domain *mem_cgroup_wb_domain(struct bdi_writeback *wb); diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h index 98a80c01d150..9da23c019dc5 100644 --- a/include/linux/mmzone.h +++ b/include/linux/mmzone.h @@ -276,6 +276,8 @@ enum lruvec_flags { struct lruvec { struct list_head lists[NR_LRU_LISTS]; + /* per lruvec lru_lock for memcg */ + spinlock_t lru_lock; /* * These track the cost of reclaiming one LRU - file or anon - * over the other. As the observed cost of reclaiming one LRU @@ -782,7 +784,6 @@ typedef struct pglist_data { /* Write-intensive fields used by page reclaim */ ZONE_PADDING(_pad1_) - spinlock_t lru_lock; #ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT /* diff --git a/mm/compaction.c b/mm/compaction.c index 50938e66083c..e5acb9714436 100644 --- a/mm/compaction.c +++ b/mm/compaction.c @@ -804,7 +804,7 @@ isolate_migratepages_block(struct compact_control *cc, unsigned long low_pfn, unsigned long nr_scanned = 0, nr_isolated = 0; struct lruvec *lruvec; unsigned long flags = 0; - bool locked = false; + struct lruvec *locked = NULL; struct page *page = NULL, *valid_page = NULL; unsigned long start_pfn = low_pfn; bool skip_on_failure = false; @@ -868,11 +868,20 @@ isolate_migratepages_block(struct compact_control *cc, unsigned long low_pfn, * contention, to give chance to IRQs. Abort completely if * a fatal signal is pending. */ - if (!(low_pfn % SWAP_CLUSTER_MAX) - && compact_unlock_should_abort(&pgdat->lru_lock, - flags, &locked, cc)) { - low_pfn = 0; - goto fatal_pending; + if (!(low_pfn % SWAP_CLUSTER_MAX)) { + if (locked) { + unlock_page_lruvec_irqrestore(locked, flags); + locked = NULL; + } + + if (fatal_signal_pending(current)) { + cc->contended = true; + + low_pfn = 0; + goto fatal_pending; + } + + cond_resched(); } if (!pfn_valid_within(low_pfn)) @@ -944,9 +953,8 @@ isolate_migratepages_block(struct compact_control *cc, unsigned long low_pfn, if (unlikely(__PageMovable(page)) && !PageIsolated(page)) { if (locked) { - spin_unlock_irqrestore(&pgdat->lru_lock, - flags); - locked = false; + unlock_page_lruvec_irqrestore(locked, flags); + locked = NULL; } if (!isolate_movable_page(page, isolate_mode)) @@ -987,10 +995,19 @@ isolate_migratepages_block(struct compact_control *cc, unsigned long low_pfn, if (!TestClearPageLRU(page)) goto isolate_fail_put; + rcu_read_lock(); + lruvec = mem_cgroup_page_lruvec(page, pgdat); + /* If we already hold the lock, we can skip some rechecking */ - if (!locked) { - locked = compact_lock_irqsave(&pgdat->lru_lock, - &flags, cc); + if (lruvec != locked) { + if (locked) + unlock_page_lruvec_irqrestore(locked, flags); + + compact_lock_irqsave(&lruvec->lru_lock, &flags, cc); + locked = lruvec; + rcu_read_unlock(); + + lruvec_memcg_debug(lruvec, page); /* Try get exclusive access under lock */ if (!skip_updated) { @@ -1009,9 +1026,8 @@ isolate_migratepages_block(struct compact_control *cc, unsigned long low_pfn, SetPageLRU(page); goto isolate_fail_put; } - } - - lruvec = mem_cgroup_page_lruvec(page, pgdat); + } else + rcu_read_unlock(); /* The whole page is taken off the LRU; skip the tail pages. */ if (PageCompound(page)) @@ -1045,8 +1061,8 @@ isolate_success: isolate_fail_put: /* Avoid potential deadlock in freeing page under lru_lock */ if (locked) { - spin_unlock_irqrestore(&pgdat->lru_lock, flags); - locked = false; + unlock_page_lruvec_irqrestore(locked, flags); + locked = NULL; } put_page(page); @@ -1061,8 +1077,8 @@ isolate_fail: */ if (nr_isolated) { if (locked) { - spin_unlock_irqrestore(&pgdat->lru_lock, flags); - locked = false; + unlock_page_lruvec_irqrestore(locked, flags); + locked = NULL; } putback_movable_pages(&cc->migratepages); cc->nr_migratepages = 0; @@ -1090,7 +1106,7 @@ isolate_fail: isolate_abort: if (locked) - spin_unlock_irqrestore(&pgdat->lru_lock, flags); + unlock_page_lruvec_irqrestore(locked, flags); if (page) { SetPageLRU(page); put_page(page); diff --git a/mm/huge_memory.c b/mm/huge_memory.c index a59333aa4020..3c4a8fc9102f 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -2365,7 +2365,7 @@ static void lru_add_page_tail(struct page *head, struct page *tail, VM_BUG_ON_PAGE(!PageHead(head), head); VM_BUG_ON_PAGE(PageCompound(tail), head); VM_BUG_ON_PAGE(PageLRU(tail), head); - lockdep_assert_held(&lruvec_pgdat(lruvec)->lru_lock); + lockdep_assert_held(&lruvec->lru_lock); if (list) { /* page reclaim is reclaiming a huge page */ @@ -2449,7 +2449,6 @@ static void __split_huge_page(struct page *page, struct list_head *list, pgoff_t end) { struct page *head = compound_head(page); - pg_data_t *pgdat = page_pgdat(head); struct lruvec *lruvec; struct address_space *swap_cache = NULL; unsigned long offset = 0; @@ -2467,10 +2466,8 @@ static void __split_huge_page(struct page *page, struct list_head *list, xa_lock(&swap_cache->i_pages); } - /* prevent PageLRU to go away from under us, and freeze lru stats */ - spin_lock(&pgdat->lru_lock); - - lruvec = mem_cgroup_page_lruvec(head, pgdat); + /* lock lru list/PageCompound, ref freezed by page_ref_freeze */ + lruvec = lock_page_lruvec(head); for (i = nr - 1; i >= 1; i--) { __split_huge_page_tail(head, i, lruvec, list); @@ -2491,7 +2488,7 @@ static void __split_huge_page(struct page *page, struct list_head *list, } ClearPageCompound(head); - spin_unlock(&pgdat->lru_lock); + unlock_page_lruvec(lruvec); /* Caller disabled irqs, so they are still disabled here */ split_page_owner(head, nr); diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 827879d8d447..2f7824d0c897 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -20,6 +20,9 @@ * Lockless page tracking & accounting * Unified hierarchy configuration model * Copyright (C) 2015 Red Hat, Inc., Johannes Weiner + * + * Per memcg lru locking + * Copyright (C) 2020 Alibaba, Inc, Alex Shi */ #include @@ -1330,6 +1333,23 @@ int mem_cgroup_scan_tasks(struct mem_cgroup *memcg, return ret; } +#ifdef CONFIG_DEBUG_VM +void lruvec_memcg_debug(struct lruvec *lruvec, struct page *page) +{ + struct mem_cgroup *memcg; + + if (mem_cgroup_disabled()) + return; + + memcg = page_memcg(page); + + if (!memcg) + VM_BUG_ON_PAGE(lruvec_memcg(lruvec) != root_mem_cgroup, page); + else + VM_BUG_ON_PAGE(lruvec_memcg(lruvec) != memcg, page); +} +#endif + /** * mem_cgroup_page_lruvec - return lruvec for isolating/putting an LRU page * @page: the page @@ -1370,6 +1390,60 @@ out: return lruvec; } +/** + * lock_page_lruvec - lock and return lruvec for a given page. + * @page: the page + * + * This series functions should be used in either conditions: + * PageLRU is cleared or unset + * or page->_refcount is zero + * or page is locked. + */ +struct lruvec *lock_page_lruvec(struct page *page) +{ + struct lruvec *lruvec; + struct pglist_data *pgdat = page_pgdat(page); + + rcu_read_lock(); + lruvec = mem_cgroup_page_lruvec(page, pgdat); + spin_lock(&lruvec->lru_lock); + rcu_read_unlock(); + + lruvec_memcg_debug(lruvec, page); + + return lruvec; +} + +struct lruvec *lock_page_lruvec_irq(struct page *page) +{ + struct lruvec *lruvec; + struct pglist_data *pgdat = page_pgdat(page); + + rcu_read_lock(); + lruvec = mem_cgroup_page_lruvec(page, pgdat); + spin_lock_irq(&lruvec->lru_lock); + rcu_read_unlock(); + + lruvec_memcg_debug(lruvec, page); + + return lruvec; +} + +struct lruvec *lock_page_lruvec_irqsave(struct page *page, unsigned long *flags) +{ + struct lruvec *lruvec; + struct pglist_data *pgdat = page_pgdat(page); + + rcu_read_lock(); + lruvec = mem_cgroup_page_lruvec(page, pgdat); + spin_lock_irqsave(&lruvec->lru_lock, *flags); + rcu_read_unlock(); + + lruvec_memcg_debug(lruvec, page); + + return lruvec; +} + /** * mem_cgroup_update_lru_size - account for adding or removing an lru page * @lruvec: mem_cgroup per zone lru vector @@ -3281,10 +3355,8 @@ void obj_cgroup_uncharge(struct obj_cgroup *objcg, size_t size) #endif /* CONFIG_MEMCG_KMEM */ #ifdef CONFIG_TRANSPARENT_HUGEPAGE - /* - * Because tail pages are not marked as "used", set it. We're under - * pgdat->lru_lock and migration entries setup in all page mappings. + * Because page_memcg(head) is not set on compound tails, set it now. */ void mem_cgroup_split_huge_fixup(struct page *head) { diff --git a/mm/mlock.c b/mm/mlock.c index 7b0e6334be6f..ab164a675c25 100644 --- a/mm/mlock.c +++ b/mm/mlock.c @@ -262,12 +262,12 @@ static void __munlock_pagevec(struct pagevec *pvec, struct zone *zone) int nr = pagevec_count(pvec); int delta_munlocked = -nr; struct pagevec pvec_putback; + struct lruvec *lruvec = NULL; int pgrescued = 0; pagevec_init(&pvec_putback); /* Phase 1: page isolation */ - spin_lock_irq(&zone->zone_pgdat->lru_lock); for (i = 0; i < nr; i++) { struct page *page = pvec->pages[i]; @@ -277,10 +277,16 @@ static void __munlock_pagevec(struct pagevec *pvec, struct zone *zone) * so we can spare the get_page() here. */ if (TestClearPageLRU(page)) { - struct lruvec *lruvec; + struct lruvec *new_lruvec; + + new_lruvec = mem_cgroup_page_lruvec(page, + page_pgdat(page)); + if (new_lruvec != lruvec) { + if (lruvec) + unlock_page_lruvec_irq(lruvec); + lruvec = lock_page_lruvec_irq(page); + } - lruvec = mem_cgroup_page_lruvec(page, - page_pgdat(page)); del_page_from_lru_list(page, lruvec, page_lru(page)); continue; @@ -299,8 +305,12 @@ static void __munlock_pagevec(struct pagevec *pvec, struct zone *zone) pagevec_add(&pvec_putback, pvec->pages[i]); pvec->pages[i] = NULL; } - __mod_zone_page_state(zone, NR_MLOCK, delta_munlocked); - spin_unlock_irq(&zone->zone_pgdat->lru_lock); + if (lruvec) { + __mod_zone_page_state(zone, NR_MLOCK, delta_munlocked); + unlock_page_lruvec_irq(lruvec); + } else if (delta_munlocked) { + mod_zone_page_state(zone, NR_MLOCK, delta_munlocked); + } /* Now we can release pins of pages that we are not munlocking */ pagevec_release(&pvec_putback); diff --git a/mm/mmzone.c b/mm/mmzone.c index f337831affc2..eb89d6e018e2 100644 --- a/mm/mmzone.c +++ b/mm/mmzone.c @@ -77,6 +77,7 @@ void lruvec_init(struct lruvec *lruvec) enum lru_list lru; memset(lruvec, 0, sizeof(struct lruvec)); + spin_lock_init(&lruvec->lru_lock); for_each_lru(lru) INIT_LIST_HEAD(&lruvec->lists[lru]); diff --git a/mm/page_alloc.c b/mm/page_alloc.c index b63294517e04..b1cc2b7483a1 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -6870,7 +6870,6 @@ static void __meminit pgdat_init_internals(struct pglist_data *pgdat) init_waitqueue_head(&pgdat->pfmemalloc_wait); pgdat_page_ext_init(pgdat); - spin_lock_init(&pgdat->lru_lock); lruvec_init(&pgdat->__lruvec); } diff --git a/mm/swap.c b/mm/swap.c index d952af770053..ba9fc21b24ea 100644 --- a/mm/swap.c +++ b/mm/swap.c @@ -79,16 +79,14 @@ static DEFINE_PER_CPU(struct lru_pvecs, lru_pvecs) = { static void __page_cache_release(struct page *page) { if (PageLRU(page)) { - pg_data_t *pgdat = page_pgdat(page); struct lruvec *lruvec; unsigned long flags; - spin_lock_irqsave(&pgdat->lru_lock, flags); - lruvec = mem_cgroup_page_lruvec(page, pgdat); + lruvec = lock_page_lruvec_irqsave(page, &flags); VM_BUG_ON_PAGE(!PageLRU(page), page); __ClearPageLRU(page); del_page_from_lru_list(page, lruvec, page_off_lru(page)); - spin_unlock_irqrestore(&pgdat->lru_lock, flags); + unlock_page_lruvec_irqrestore(lruvec, flags); } __ClearPageWaiters(page); } @@ -207,32 +205,30 @@ static void pagevec_lru_move_fn(struct pagevec *pvec, void (*move_fn)(struct page *page, struct lruvec *lruvec)) { int i; - struct pglist_data *pgdat = NULL; - struct lruvec *lruvec; + struct lruvec *lruvec = NULL; unsigned long flags = 0; for (i = 0; i < pagevec_count(pvec); i++) { struct page *page = pvec->pages[i]; - struct pglist_data *pagepgdat = page_pgdat(page); - - if (pagepgdat != pgdat) { - if (pgdat) - spin_unlock_irqrestore(&pgdat->lru_lock, flags); - pgdat = pagepgdat; - spin_lock_irqsave(&pgdat->lru_lock, flags); - } + struct lruvec *new_lruvec; /* block memcg migration during page moving between lru */ if (!TestClearPageLRU(page)) continue; - lruvec = mem_cgroup_page_lruvec(page, pgdat); + new_lruvec = mem_cgroup_page_lruvec(page, page_pgdat(page)); + if (lruvec != new_lruvec) { + if (lruvec) + unlock_page_lruvec_irqrestore(lruvec, flags); + lruvec = lock_page_lruvec_irqsave(page, &flags); + } + (*move_fn)(page, lruvec); SetPageLRU(page); } - if (pgdat) - spin_unlock_irqrestore(&pgdat->lru_lock, flags); + if (lruvec) + unlock_page_lruvec_irqrestore(lruvec, flags); release_pages(pvec->pages, pvec->nr); pagevec_reinit(pvec); } @@ -274,9 +270,15 @@ void lru_note_cost(struct lruvec *lruvec, bool file, unsigned int nr_pages) { do { unsigned long lrusize; - struct pglist_data *pgdat = lruvec_pgdat(lruvec); - spin_lock_irq(&pgdat->lru_lock); + /* + * Hold lruvec->lru_lock is safe here, since + * 1) The pinned lruvec in reclaim, or + * 2) From a pre-LRU page during refault (which also holds the + * rcu lock, so would be safe even if the page was on the LRU + * and could move simultaneously to a new lruvec). + */ + spin_lock_irq(&lruvec->lru_lock); /* Record cost event */ if (file) lruvec->file_cost += nr_pages; @@ -300,7 +302,7 @@ void lru_note_cost(struct lruvec *lruvec, bool file, unsigned int nr_pages) lruvec->file_cost /= 2; lruvec->anon_cost /= 2; } - spin_unlock_irq(&pgdat->lru_lock); + spin_unlock_irq(&lruvec->lru_lock); } while ((lruvec = parent_lruvec(lruvec))); } @@ -364,13 +366,15 @@ static inline void activate_page_drain(int cpu) static void activate_page(struct page *page) { - pg_data_t *pgdat = page_pgdat(page); + struct lruvec *lruvec; page = compound_head(page); - spin_lock_irq(&pgdat->lru_lock); - if (PageLRU(page)) - __activate_page(page, mem_cgroup_page_lruvec(page, pgdat)); - spin_unlock_irq(&pgdat->lru_lock); + if (TestClearPageLRU(page)) { + lruvec = lock_page_lruvec_irq(page); + __activate_page(page, lruvec); + unlock_page_lruvec_irq(lruvec); + SetPageLRU(page); + } } #endif @@ -860,8 +864,7 @@ void release_pages(struct page **pages, int nr) { int i; LIST_HEAD(pages_to_free); - struct pglist_data *locked_pgdat = NULL; - struct lruvec *lruvec; + struct lruvec *lruvec = NULL; unsigned long flags; unsigned int lock_batch; @@ -871,11 +874,11 @@ void release_pages(struct page **pages, int nr) /* * Make sure the IRQ-safe lock-holding time does not get * excessive with a continuous string of pages from the - * same pgdat. The lock is held only if pgdat != NULL. + * same lruvec. The lock is held only if lruvec != NULL. */ - if (locked_pgdat && ++lock_batch == SWAP_CLUSTER_MAX) { - spin_unlock_irqrestore(&locked_pgdat->lru_lock, flags); - locked_pgdat = NULL; + if (lruvec && ++lock_batch == SWAP_CLUSTER_MAX) { + unlock_page_lruvec_irqrestore(lruvec, flags); + lruvec = NULL; } page = compound_head(page); @@ -883,10 +886,9 @@ void release_pages(struct page **pages, int nr) continue; if (is_zone_device_page(page)) { - if (locked_pgdat) { - spin_unlock_irqrestore(&locked_pgdat->lru_lock, - flags); - locked_pgdat = NULL; + if (lruvec) { + unlock_page_lruvec_irqrestore(lruvec, flags); + lruvec = NULL; } /* * ZONE_DEVICE pages that return 'false' from @@ -907,27 +909,27 @@ void release_pages(struct page **pages, int nr) continue; if (PageCompound(page)) { - if (locked_pgdat) { - spin_unlock_irqrestore(&locked_pgdat->lru_lock, flags); - locked_pgdat = NULL; + if (lruvec) { + unlock_page_lruvec_irqrestore(lruvec, flags); + lruvec = NULL; } __put_compound_page(page); continue; } if (PageLRU(page)) { - struct pglist_data *pgdat = page_pgdat(page); + struct lruvec *new_lruvec; - if (pgdat != locked_pgdat) { - if (locked_pgdat) - spin_unlock_irqrestore(&locked_pgdat->lru_lock, + new_lruvec = mem_cgroup_page_lruvec(page, + page_pgdat(page)); + if (new_lruvec != lruvec) { + if (lruvec) + unlock_page_lruvec_irqrestore(lruvec, flags); lock_batch = 0; - locked_pgdat = pgdat; - spin_lock_irqsave(&locked_pgdat->lru_lock, flags); + lruvec = lock_page_lruvec_irqsave(page, &flags); } - lruvec = mem_cgroup_page_lruvec(page, locked_pgdat); VM_BUG_ON_PAGE(!PageLRU(page), page); __ClearPageLRU(page); del_page_from_lru_list(page, lruvec, page_off_lru(page)); @@ -937,8 +939,8 @@ void release_pages(struct page **pages, int nr) list_add(&page->lru, &pages_to_free); } - if (locked_pgdat) - spin_unlock_irqrestore(&locked_pgdat->lru_lock, flags); + if (lruvec) + unlock_page_lruvec_irqrestore(lruvec, flags); mem_cgroup_uncharge_list(&pages_to_free); free_unref_page_list(&pages_to_free); @@ -1026,26 +1028,24 @@ static void __pagevec_lru_add_fn(struct page *page, struct lruvec *lruvec) void __pagevec_lru_add(struct pagevec *pvec) { int i; - struct pglist_data *pgdat = NULL; - struct lruvec *lruvec; + struct lruvec *lruvec = NULL; unsigned long flags = 0; for (i = 0; i < pagevec_count(pvec); i++) { struct page *page = pvec->pages[i]; - struct pglist_data *pagepgdat = page_pgdat(page); + struct lruvec *new_lruvec; - if (pagepgdat != pgdat) { - if (pgdat) - spin_unlock_irqrestore(&pgdat->lru_lock, flags); - pgdat = pagepgdat; - spin_lock_irqsave(&pgdat->lru_lock, flags); + new_lruvec = mem_cgroup_page_lruvec(page, page_pgdat(page)); + if (lruvec != new_lruvec) { + if (lruvec) + unlock_page_lruvec_irqrestore(lruvec, flags); + lruvec = lock_page_lruvec_irqsave(page, &flags); } - lruvec = mem_cgroup_page_lruvec(page, pgdat); __pagevec_lru_add_fn(page, lruvec); } - if (pgdat) - spin_unlock_irqrestore(&pgdat->lru_lock, flags); + if (lruvec) + unlock_page_lruvec_irqrestore(lruvec, flags); release_pages(pvec->pages, pvec->nr); pagevec_reinit(pvec); } diff --git a/mm/vmscan.c b/mm/vmscan.c index cf99e66e7f33..b27b5dba3fdd 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -1764,14 +1764,12 @@ int isolate_lru_page(struct page *page) WARN_RATELIMIT(PageTail(page), "trying to isolate tail page"); if (TestClearPageLRU(page)) { - pg_data_t *pgdat = page_pgdat(page); struct lruvec *lruvec; get_page(page); - lruvec = mem_cgroup_page_lruvec(page, pgdat); - spin_lock_irq(&pgdat->lru_lock); + lruvec = lock_page_lruvec_irq(page); del_page_from_lru_list(page, lruvec, page_lru(page)); - spin_unlock_irq(&pgdat->lru_lock); + unlock_page_lruvec_irq(lruvec); ret = 0; } @@ -1838,7 +1836,6 @@ static int too_many_isolated(struct pglist_data *pgdat, int file, static unsigned noinline_for_stack move_pages_to_lru(struct lruvec *lruvec, struct list_head *list) { - struct pglist_data *pgdat = lruvec_pgdat(lruvec); int nr_pages, nr_moved = 0; LIST_HEAD(pages_to_free); struct page *page; @@ -1849,9 +1846,9 @@ static unsigned noinline_for_stack move_pages_to_lru(struct lruvec *lruvec, VM_BUG_ON_PAGE(PageLRU(page), page); list_del(&page->lru); if (unlikely(!page_evictable(page))) { - spin_unlock_irq(&pgdat->lru_lock); + spin_unlock_irq(&lruvec->lru_lock); putback_lru_page(page); - spin_lock_irq(&pgdat->lru_lock); + spin_lock_irq(&lruvec->lru_lock); continue; } @@ -1873,9 +1870,9 @@ static unsigned noinline_for_stack move_pages_to_lru(struct lruvec *lruvec, __ClearPageActive(page); if (unlikely(PageCompound(page))) { - spin_unlock_irq(&pgdat->lru_lock); + spin_unlock_irq(&lruvec->lru_lock); destroy_compound_page(page); - spin_lock_irq(&pgdat->lru_lock); + spin_lock_irq(&lruvec->lru_lock); } else list_add(&page->lru, &pages_to_free); @@ -1952,7 +1949,7 @@ shrink_inactive_list(unsigned long nr_to_scan, struct lruvec *lruvec, lru_add_drain(); - spin_lock_irq(&pgdat->lru_lock); + spin_lock_irq(&lruvec->lru_lock); nr_taken = isolate_lru_pages(nr_to_scan, lruvec, &page_list, &nr_scanned, sc, lru); @@ -1964,14 +1961,14 @@ shrink_inactive_list(unsigned long nr_to_scan, struct lruvec *lruvec, __count_memcg_events(lruvec_memcg(lruvec), item, nr_scanned); __count_vm_events(PGSCAN_ANON + file, nr_scanned); - spin_unlock_irq(&pgdat->lru_lock); + spin_unlock_irq(&lruvec->lru_lock); if (nr_taken == 0) return 0; nr_reclaimed = shrink_page_list(&page_list, pgdat, sc, &stat, false); - spin_lock_irq(&pgdat->lru_lock); + spin_lock_irq(&lruvec->lru_lock); move_pages_to_lru(lruvec, &page_list); __mod_node_page_state(pgdat, NR_ISOLATED_ANON + file, -nr_taken); @@ -1980,7 +1977,7 @@ shrink_inactive_list(unsigned long nr_to_scan, struct lruvec *lruvec, __count_vm_events(item, nr_reclaimed); __count_memcg_events(lruvec_memcg(lruvec), item, nr_reclaimed); __count_vm_events(PGSTEAL_ANON + file, nr_reclaimed); - spin_unlock_irq(&pgdat->lru_lock); + spin_unlock_irq(&lruvec->lru_lock); lru_note_cost(lruvec, file, stat.nr_pageout); mem_cgroup_uncharge_list(&page_list); @@ -2033,7 +2030,7 @@ static void shrink_active_list(unsigned long nr_to_scan, lru_add_drain(); - spin_lock_irq(&pgdat->lru_lock); + spin_lock_irq(&lruvec->lru_lock); nr_taken = isolate_lru_pages(nr_to_scan, lruvec, &l_hold, &nr_scanned, sc, lru); @@ -2044,7 +2041,7 @@ static void shrink_active_list(unsigned long nr_to_scan, __count_vm_events(PGREFILL, nr_scanned); __count_memcg_events(lruvec_memcg(lruvec), PGREFILL, nr_scanned); - spin_unlock_irq(&pgdat->lru_lock); + spin_unlock_irq(&lruvec->lru_lock); while (!list_empty(&l_hold)) { cond_resched(); @@ -2090,7 +2087,7 @@ static void shrink_active_list(unsigned long nr_to_scan, /* * Move pages back to the lru list. */ - spin_lock_irq(&pgdat->lru_lock); + spin_lock_irq(&lruvec->lru_lock); nr_activate = move_pages_to_lru(lruvec, &l_active); nr_deactivate = move_pages_to_lru(lruvec, &l_inactive); @@ -2101,7 +2098,7 @@ static void shrink_active_list(unsigned long nr_to_scan, __count_memcg_events(lruvec_memcg(lruvec), PGDEACTIVATE, nr_deactivate); __mod_node_page_state(pgdat, NR_ISOLATED_ANON + file, -nr_taken); - spin_unlock_irq(&pgdat->lru_lock); + spin_unlock_irq(&lruvec->lru_lock); mem_cgroup_uncharge_list(&l_active); free_unref_page_list(&l_active); @@ -2689,10 +2686,10 @@ again: /* * Determine the scan balance between anon and file LRUs. */ - spin_lock_irq(&pgdat->lru_lock); + spin_lock_irq(&target_lruvec->lru_lock); sc->anon_cost = target_lruvec->anon_cost; sc->file_cost = target_lruvec->file_cost; - spin_unlock_irq(&pgdat->lru_lock); + spin_unlock_irq(&target_lruvec->lru_lock); /* * Target desirable inactive:active list ratios for the anon @@ -4268,16 +4265,15 @@ int node_reclaim(struct pglist_data *pgdat, gfp_t gfp_mask, unsigned int order) */ void check_move_unevictable_pages(struct pagevec *pvec) { - struct lruvec *lruvec; - struct pglist_data *pgdat = NULL; + struct lruvec *lruvec = NULL; int pgscanned = 0; int pgrescued = 0; int i; for (i = 0; i < pvec->nr; i++) { struct page *page = pvec->pages[i]; - struct pglist_data *pagepgdat = page_pgdat(page); int nr_pages; + struct lruvec *new_lruvec; if (PageTransTail(page)) continue; @@ -4289,13 +4285,12 @@ void check_move_unevictable_pages(struct pagevec *pvec) if (!TestClearPageLRU(page)) continue; - if (pagepgdat != pgdat) { - if (pgdat) - spin_unlock_irq(&pgdat->lru_lock); - pgdat = pagepgdat; - spin_lock_irq(&pgdat->lru_lock); + new_lruvec = mem_cgroup_page_lruvec(page, page_pgdat(page)); + if (lruvec != new_lruvec) { + if (lruvec) + unlock_page_lruvec_irq(lruvec); + lruvec = lock_page_lruvec_irq(page); } - lruvec = mem_cgroup_page_lruvec(page, pgdat); if (page_evictable(page) && PageUnevictable(page)) { enum lru_list lru = page_lru_base_type(page); @@ -4309,10 +4304,10 @@ void check_move_unevictable_pages(struct pagevec *pvec) SetPageLRU(page); } - if (pgdat) { + if (lruvec) { __count_vm_events(UNEVICTABLE_PGRESCUED, pgrescued); __count_vm_events(UNEVICTABLE_PGSCANNED, pgscanned); - spin_unlock_irq(&pgdat->lru_lock); + unlock_page_lruvec_irq(lruvec); } else if (pgscanned) { count_vm_events(UNEVICTABLE_PGSCANNED, pgscanned); } -- cgit v1.3-14-g43fede From 2a5e4e340b0fe0f8d402196a466887db6a270b9b Mon Sep 17 00:00:00 2001 From: Alexander Duyck Date: Tue, 15 Dec 2020 12:34:33 -0800 Subject: mm/lru: introduce relock_page_lruvec() MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Add relock_page_lruvec() to replace repeated same code, no functional change. When testing for relock we can avoid the need for RCU locking if we simply compare the page pgdat and memcg pointers versus those that the lruvec is holding. By doing this we can avoid the extra pointer walks and accesses of the memory cgroup. In addition we can avoid the checks entirely if lruvec is currently NULL. [alex.shi@linux.alibaba.com: use page_memcg()] Link: https://lkml.kernel.org/r/66d8e79d-7ec6-bfbc-1c82-bf32db3ae5b7@linux.alibaba.com Link: https://lkml.kernel.org/r/1604566549-62481-19-git-send-email-alex.shi@linux.alibaba.com Signed-off-by: Alexander Duyck Signed-off-by: Alex Shi Acked-by: Hugh Dickins Acked-by: Johannes Weiner Acked-by: Vlastimil Babka Cc: Thomas Gleixner Cc: Andrey Ryabinin Cc: Matthew Wilcox Cc: Mel Gorman Cc: Konstantin Khlebnikov Cc: Tejun Heo Cc: Andrea Arcangeli Cc: "Chen, Rong A" Cc: Daniel Jordan Cc: "Huang, Ying" Cc: Jann Horn Cc: Joonsoo Kim Cc: Kirill A. Shutemov Cc: Kirill A. Shutemov Cc: Michal Hocko Cc: Michal Hocko Cc: Mika Penttilä Cc: Minchan Kim Cc: Shakeel Butt Cc: Vladimir Davydov Cc: Wei Yang Cc: Yang Shi Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/memcontrol.h | 52 ++++++++++++++++++++++++++++++++++++++++++++++ mm/mlock.c | 11 +--------- mm/swap.c | 33 +++++++---------------------- mm/vmscan.c | 12 ++--------- 4 files changed, 62 insertions(+), 46 deletions(-) (limited to 'include/linux/memcontrol.h') diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h index aa5d559853c2..ff02f831e7e1 100644 --- a/include/linux/memcontrol.h +++ b/include/linux/memcontrol.h @@ -485,6 +485,22 @@ out: struct lruvec *mem_cgroup_page_lruvec(struct page *, struct pglist_data *); +static inline bool lruvec_holds_page_lru_lock(struct page *page, + struct lruvec *lruvec) +{ + pg_data_t *pgdat = page_pgdat(page); + const struct mem_cgroup *memcg; + struct mem_cgroup_per_node *mz; + + if (mem_cgroup_disabled()) + return lruvec == &pgdat->__lruvec; + + mz = container_of(lruvec, struct mem_cgroup_per_node, lruvec); + memcg = page_memcg(page) ? : root_mem_cgroup; + + return lruvec->pgdat == pgdat && mz->memcg == memcg; +} + struct mem_cgroup *mem_cgroup_from_task(struct task_struct *p); struct mem_cgroup *get_mem_cgroup_from_mm(struct mm_struct *mm); @@ -984,6 +1000,14 @@ static inline struct lruvec *mem_cgroup_page_lruvec(struct page *page, return &pgdat->__lruvec; } +static inline bool lruvec_holds_page_lru_lock(struct page *page, + struct lruvec *lruvec) +{ + pg_data_t *pgdat = page_pgdat(page); + + return lruvec == &pgdat->__lruvec; +} + static inline struct mem_cgroup *parent_mem_cgroup(struct mem_cgroup *memcg) { return NULL; @@ -1354,6 +1378,34 @@ static inline void unlock_page_lruvec_irqrestore(struct lruvec *lruvec, spin_unlock_irqrestore(&lruvec->lru_lock, flags); } +/* Don't lock again iff page's lruvec locked */ +static inline struct lruvec *relock_page_lruvec_irq(struct page *page, + struct lruvec *locked_lruvec) +{ + if (locked_lruvec) { + if (lruvec_holds_page_lru_lock(page, locked_lruvec)) + return locked_lruvec; + + unlock_page_lruvec_irq(locked_lruvec); + } + + return lock_page_lruvec_irq(page); +} + +/* Don't lock again iff page's lruvec locked */ +static inline struct lruvec *relock_page_lruvec_irqsave(struct page *page, + struct lruvec *locked_lruvec, unsigned long *flags) +{ + if (locked_lruvec) { + if (lruvec_holds_page_lru_lock(page, locked_lruvec)) + return locked_lruvec; + + unlock_page_lruvec_irqrestore(locked_lruvec, *flags); + } + + return lock_page_lruvec_irqsave(page, flags); +} + #ifdef CONFIG_CGROUP_WRITEBACK struct wb_domain *mem_cgroup_wb_domain(struct bdi_writeback *wb); diff --git a/mm/mlock.c b/mm/mlock.c index ab164a675c25..55b3b3672977 100644 --- a/mm/mlock.c +++ b/mm/mlock.c @@ -277,16 +277,7 @@ static void __munlock_pagevec(struct pagevec *pvec, struct zone *zone) * so we can spare the get_page() here. */ if (TestClearPageLRU(page)) { - struct lruvec *new_lruvec; - - new_lruvec = mem_cgroup_page_lruvec(page, - page_pgdat(page)); - if (new_lruvec != lruvec) { - if (lruvec) - unlock_page_lruvec_irq(lruvec); - lruvec = lock_page_lruvec_irq(page); - } - + lruvec = relock_page_lruvec_irq(page, lruvec); del_page_from_lru_list(page, lruvec, page_lru(page)); continue; diff --git a/mm/swap.c b/mm/swap.c index ba9fc21b24ea..2cca7141470c 100644 --- a/mm/swap.c +++ b/mm/swap.c @@ -210,19 +210,12 @@ static void pagevec_lru_move_fn(struct pagevec *pvec, for (i = 0; i < pagevec_count(pvec); i++) { struct page *page = pvec->pages[i]; - struct lruvec *new_lruvec; /* block memcg migration during page moving between lru */ if (!TestClearPageLRU(page)) continue; - new_lruvec = mem_cgroup_page_lruvec(page, page_pgdat(page)); - if (lruvec != new_lruvec) { - if (lruvec) - unlock_page_lruvec_irqrestore(lruvec, flags); - lruvec = lock_page_lruvec_irqsave(page, &flags); - } - + lruvec = relock_page_lruvec_irqsave(page, lruvec, &flags); (*move_fn)(page, lruvec); SetPageLRU(page); @@ -918,17 +911,12 @@ void release_pages(struct page **pages, int nr) } if (PageLRU(page)) { - struct lruvec *new_lruvec; - - new_lruvec = mem_cgroup_page_lruvec(page, - page_pgdat(page)); - if (new_lruvec != lruvec) { - if (lruvec) - unlock_page_lruvec_irqrestore(lruvec, - flags); + struct lruvec *prev_lruvec = lruvec; + + lruvec = relock_page_lruvec_irqsave(page, lruvec, + &flags); + if (prev_lruvec != lruvec) lock_batch = 0; - lruvec = lock_page_lruvec_irqsave(page, &flags); - } VM_BUG_ON_PAGE(!PageLRU(page), page); __ClearPageLRU(page); @@ -1033,15 +1021,8 @@ void __pagevec_lru_add(struct pagevec *pvec) for (i = 0; i < pagevec_count(pvec); i++) { struct page *page = pvec->pages[i]; - struct lruvec *new_lruvec; - - new_lruvec = mem_cgroup_page_lruvec(page, page_pgdat(page)); - if (lruvec != new_lruvec) { - if (lruvec) - unlock_page_lruvec_irqrestore(lruvec, flags); - lruvec = lock_page_lruvec_irqsave(page, &flags); - } + lruvec = relock_page_lruvec_irqsave(page, lruvec, &flags); __pagevec_lru_add_fn(page, lruvec); } if (lruvec) diff --git a/mm/vmscan.c b/mm/vmscan.c index b27b5dba3fdd..60705ea598ee 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -1883,8 +1883,7 @@ static unsigned noinline_for_stack move_pages_to_lru(struct lruvec *lruvec, * All pages were isolated from the same lruvec (and isolation * inhibits memcg migration). */ - VM_BUG_ON_PAGE(mem_cgroup_page_lruvec(page, page_pgdat(page)) - != lruvec, page); + VM_BUG_ON_PAGE(!lruvec_holds_page_lru_lock(page, lruvec), page); lru = page_lru(page); nr_pages = thp_nr_pages(page); @@ -4273,7 +4272,6 @@ void check_move_unevictable_pages(struct pagevec *pvec) for (i = 0; i < pvec->nr; i++) { struct page *page = pvec->pages[i]; int nr_pages; - struct lruvec *new_lruvec; if (PageTransTail(page)) continue; @@ -4285,13 +4283,7 @@ void check_move_unevictable_pages(struct pagevec *pvec) if (!TestClearPageLRU(page)) continue; - new_lruvec = mem_cgroup_page_lruvec(page, page_pgdat(page)); - if (lruvec != new_lruvec) { - if (lruvec) - unlock_page_lruvec_irq(lruvec); - lruvec = lock_page_lruvec_irq(page); - } - + lruvec = relock_page_lruvec_irq(page, lruvec); if (page_evictable(page) && PageUnevictable(page)) { enum lru_list lru = page_lru_base_type(page); -- cgit v1.3-14-g43fede From bec78efd0061365a76f88e498affd7106b256823 Mon Sep 17 00:00:00 2001 From: Wei Yang Date: Fri, 18 Dec 2020 14:01:35 -0800 Subject: mm/memcg: remove unused definitions Some definitions are left unused, just clean them. Link: https://lkml.kernel.org/r/20201108003834.12669-1-richard.weiyang@gmail.com Signed-off-by: Wei Yang Acked-by: Michal Hocko Reviewed-by: Shakeel Butt Reviewed-by: Roman Gushchin Cc: Johannes Weiner Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/memcontrol.h | 118 --------------------------------------------- 1 file changed, 118 deletions(-) (limited to 'include/linux/memcontrol.h') diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h index 08ed57e02b73..196441f5dc99 100644 --- a/include/linux/memcontrol.h +++ b/include/linux/memcontrol.h @@ -913,41 +913,6 @@ static inline void mod_memcg_state(struct mem_cgroup *memcg, local_irq_restore(flags); } -/** - * mod_memcg_page_state - update page state statistics - * @page: the page - * @idx: page state item to account - * @val: number of pages (positive or negative) - * - * The @page must be locked or the caller must use lock_page_memcg() - * to prevent double accounting when the page is concurrently being - * moved to another memcg: - * - * lock_page(page) or lock_page_memcg(page) - * if (TestClearPageState(page)) - * mod_memcg_page_state(page, state, -1); - * unlock_page(page) or unlock_page_memcg(page) - * - * Kernel pages are an exception to this, since they'll never move. - */ -static inline void __mod_memcg_page_state(struct page *page, - int idx, int val) -{ - struct mem_cgroup *memcg = page_memcg(page); - - if (memcg) - __mod_memcg_state(memcg, idx, val); -} - -static inline void mod_memcg_page_state(struct page *page, - int idx, int val) -{ - struct mem_cgroup *memcg = page_memcg(page); - - if (memcg) - mod_memcg_state(memcg, idx, val); -} - static inline unsigned long lruvec_page_state(struct lruvec *lruvec, enum node_stat_item idx) { @@ -1395,18 +1360,6 @@ static inline void mod_memcg_state(struct mem_cgroup *memcg, { } -static inline void __mod_memcg_page_state(struct page *page, - int idx, - int nr) -{ -} - -static inline void mod_memcg_page_state(struct page *page, - int idx, - int nr) -{ -} - static inline unsigned long lruvec_page_state(struct lruvec *lruvec, enum node_stat_item idx) { @@ -1479,34 +1432,6 @@ static inline void lruvec_memcg_debug(struct lruvec *lruvec, struct page *page) } #endif /* CONFIG_MEMCG */ -/* idx can be of type enum memcg_stat_item or node_stat_item */ -static inline void __inc_memcg_state(struct mem_cgroup *memcg, - int idx) -{ - __mod_memcg_state(memcg, idx, 1); -} - -/* idx can be of type enum memcg_stat_item or node_stat_item */ -static inline void __dec_memcg_state(struct mem_cgroup *memcg, - int idx) -{ - __mod_memcg_state(memcg, idx, -1); -} - -/* idx can be of type enum memcg_stat_item or node_stat_item */ -static inline void __inc_memcg_page_state(struct page *page, - int idx) -{ - __mod_memcg_page_state(page, idx, 1); -} - -/* idx can be of type enum memcg_stat_item or node_stat_item */ -static inline void __dec_memcg_page_state(struct page *page, - int idx) -{ - __mod_memcg_page_state(page, idx, -1); -} - static inline void __inc_lruvec_kmem_state(void *p, enum node_stat_item idx) { __mod_lruvec_kmem_state(p, idx, 1); @@ -1517,34 +1442,6 @@ static inline void __dec_lruvec_kmem_state(void *p, enum node_stat_item idx) __mod_lruvec_kmem_state(p, idx, -1); } -/* idx can be of type enum memcg_stat_item or node_stat_item */ -static inline void inc_memcg_state(struct mem_cgroup *memcg, - int idx) -{ - mod_memcg_state(memcg, idx, 1); -} - -/* idx can be of type enum memcg_stat_item or node_stat_item */ -static inline void dec_memcg_state(struct mem_cgroup *memcg, - int idx) -{ - mod_memcg_state(memcg, idx, -1); -} - -/* idx can be of type enum memcg_stat_item or node_stat_item */ -static inline void inc_memcg_page_state(struct page *page, - int idx) -{ - mod_memcg_page_state(page, idx, 1); -} - -/* idx can be of type enum memcg_stat_item or node_stat_item */ -static inline void dec_memcg_page_state(struct page *page, - int idx) -{ - mod_memcg_page_state(page, idx, -1); -} - static inline struct lruvec *parent_lruvec(struct lruvec *lruvec) { struct mem_cgroup *memcg; @@ -1733,21 +1630,6 @@ static inline void memcg_kmem_uncharge_page(struct page *page, int order) __memcg_kmem_uncharge_page(page, order); } -static inline int memcg_kmem_charge(struct mem_cgroup *memcg, gfp_t gfp, - unsigned int nr_pages) -{ - if (memcg_kmem_enabled()) - return __memcg_kmem_charge(memcg, gfp, nr_pages); - return 0; -} - -static inline void memcg_kmem_uncharge(struct mem_cgroup *memcg, - unsigned int nr_pages) -{ - if (memcg_kmem_enabled()) - __memcg_kmem_uncharge(memcg, nr_pages); -} - /* * A helper for accessing memcg's kmem_id, used for getting * corresponding LRU lists. -- cgit v1.3-14-g43fede From 9a1ac2288cf16f9406ca54ef221bfcf262393b15 Mon Sep 17 00:00:00 2001 From: Hui Su Date: Fri, 18 Dec 2020 14:01:41 -0800 Subject: mm/memcontrol:rewrite mem_cgroup_page_lruvec() mem_cgroup_page_lruvec() in memcontrol.c and mem_cgroup_lruvec() in memcontrol.h is very similar except for the param(page and memcg) which also can be convert to each other. So rewrite mem_cgroup_page_lruvec() with mem_cgroup_lruvec(). [alex.shi@linux.alibaba.com: add missed warning in mem_cgroup_lruvec] Link: https://lkml.kernel.org/r/94f17bb7-ec61-5b72-3555-fabeb5a4d73b@linux.alibaba.com [lstoakes@gmail.com: warn on missing memcg on mem_cgroup_page_lruvec()] Link: https://lkml.kernel.org/r/20201125112202.387009-1-lstoakes@gmail.com Link: https://lkml.kernel.org/r/20201108143731.GA74138@rlk Signed-off-by: Hui Su Signed-off-by: Alex Shi Signed-off-by: Lorenzo Stoakes Acked-by: Michal Hocko Acked-by: Johannes Weiner Reviewed-by: Shakeel Butt Acked-by: Roman Gushchin Cc: Vladimir Davydov Cc: Yafang Shao Cc: Chris Down Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/memcontrol.h | 19 +++++++++++++++++-- mm/memcontrol.c | 37 ------------------------------------- 2 files changed, 17 insertions(+), 39 deletions(-) (limited to 'include/linux/memcontrol.h') diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h index 196441f5dc99..d827bd7f3bfe 100644 --- a/include/linux/memcontrol.h +++ b/include/linux/memcontrol.h @@ -620,9 +620,10 @@ mem_cgroup_nodeinfo(struct mem_cgroup *memcg, int nid) /** * mem_cgroup_lruvec - get the lru list vector for a memcg & node * @memcg: memcg of the wanted lruvec + * @pgdat: pglist_data * * Returns the lru list vector holding pages for a given @memcg & - * @node combination. This can be the node lruvec, if the memory + * @pgdat combination. This can be the node lruvec, if the memory * controller is disabled. */ static inline struct lruvec *mem_cgroup_lruvec(struct mem_cgroup *memcg, @@ -652,7 +653,21 @@ out: return lruvec; } -struct lruvec *mem_cgroup_page_lruvec(struct page *, struct pglist_data *); +/** + * mem_cgroup_page_lruvec - return lruvec for isolating/putting an LRU page + * @page: the page + * @pgdat: pgdat of the page + * + * This function relies on page->mem_cgroup being stable. + */ +static inline struct lruvec *mem_cgroup_page_lruvec(struct page *page, + struct pglist_data *pgdat) +{ + struct mem_cgroup *memcg = page_memcg(page); + + VM_WARN_ON_ONCE_PAGE(!memcg, page); + return mem_cgroup_lruvec(memcg, pgdat); +} static inline bool lruvec_holds_page_lru_lock(struct page *page, struct lruvec *lruvec) diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 7b9766789a27..605f671203ef 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -1342,43 +1342,6 @@ void lruvec_memcg_debug(struct lruvec *lruvec, struct page *page) } #endif -/** - * mem_cgroup_page_lruvec - return lruvec for isolating/putting an LRU page - * @page: the page - * @pgdat: pgdat of the page - * - * This function relies on page's memcg being stable - see the - * access rules in commit_charge(). - */ -struct lruvec *mem_cgroup_page_lruvec(struct page *page, struct pglist_data *pgdat) -{ - struct mem_cgroup_per_node *mz; - struct mem_cgroup *memcg; - struct lruvec *lruvec; - - if (mem_cgroup_disabled()) { - lruvec = &pgdat->__lruvec; - goto out; - } - - memcg = page_memcg(page); - VM_WARN_ON_ONCE_PAGE(!memcg, page); - if (!memcg) - memcg = root_mem_cgroup; - - mz = mem_cgroup_page_nodeinfo(memcg, page); - lruvec = &mz->lruvec; -out: - /* - * Since a node can be onlined after the mem_cgroup was created, - * we have to be prepared to initialize lruvec->zone here; - * and if offlined then reonlined, we need to reinitialize it. - */ - if (unlikely(lruvec->pgdat != pgdat)) - lruvec->pgdat = pgdat; - return lruvec; -} - /** * lock_page_lruvec - lock and return lruvec for a given page. * @page: the page -- cgit v1.3-14-g43fede