The quilt patch titled Subject: mm: thp: make split queue lock safe when LRU pages are reparented has been removed from the -mm tree. Its filename was mm-thp-make-split-queue-lock-safe-when-lru-pages-are-reparented.patch This patch was dropped because an updated version will be merged ------------------------------------------------------ From: Muchun Song <songmuchun@xxxxxxxxxxxxx> Subject: mm: thp: make split queue lock safe when LRU pages are reparented Date: Tue, 21 Jun 2022 20:56:53 +0800 Similar to the lruvec lock, we use the same approach to make the split queue lock safe when LRU pages are reparented. Link: https://lkml.kernel.org/r/20220621125658.64935-7-songmuchun@xxxxxxxxxxxxx Signed-off-by: Muchun Song <songmuchun@xxxxxxxxxxxxx> Acked-by: Roman Gushchin <roman.gushchin@xxxxxxxxx> Cc: Johannes Weiner <hannes@xxxxxxxxxxx> Cc: Michal Hocko <mhocko@xxxxxxxxxx> Cc: Michal Koutný <mkoutny@xxxxxxxx> Cc: Shakeel Butt <shakeelb@xxxxxxxxxx> Cc: Waiman Long <longman@xxxxxxxxxx> Cc: Xiongchun Duan <duanxiongchun@xxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- include/linux/memcontrol.h | 10 +++ mm/huge_memory.c | 116 +++++++++++++++++++++++++++-------- 2 files changed, 100 insertions(+), 26 deletions(-) --- a/include/linux/memcontrol.h~mm-thp-make-split-queue-lock-safe-when-lru-pages-are-reparented +++ a/include/linux/memcontrol.h @@ -1691,6 +1691,11 @@ int alloc_shrinker_info(struct mem_cgrou void free_shrinker_info(struct mem_cgroup *memcg); void set_shrinker_bit(struct mem_cgroup *memcg, int nid, int shrinker_id); void reparent_shrinker_deferred(struct mem_cgroup *memcg); + +static inline int shrinker_id(struct shrinker *shrinker) +{ + return shrinker->id; +} #else #define mem_cgroup_sockets_enabled 0 static inline void mem_cgroup_sk_alloc(struct sock *sk) { }; @@ -1704,6 +1709,11 @@ static inline void set_shrinker_bit(stru int nid, int shrinker_id) { } + +static inline int shrinker_id(struct shrinker *shrinker) +{ + return -1; +} #endif #ifdef CONFIG_MEMCG_KMEM --- a/mm/huge_memory.c~mm-thp-make-split-queue-lock-safe-when-lru-pages-are-reparented +++ a/mm/huge_memory.c @@ -561,25 +561,90 @@ pmd_t maybe_pmd_mkwrite(pmd_t pmd, struc } #ifdef CONFIG_MEMCG -static inline struct deferred_split *get_deferred_split_queue(struct page *page) +static inline struct mem_cgroup *folio_split_queue_memcg(struct folio *folio, + struct deferred_split *queue) { - struct mem_cgroup *memcg = page_memcg(compound_head(page)); - struct pglist_data *pgdat = NODE_DATA(page_to_nid(page)); + if (mem_cgroup_disabled()) + return NULL; + if (&NODE_DATA(folio_nid(folio))->deferred_split_queue == queue) + return NULL; + return container_of(queue, struct mem_cgroup, deferred_split_queue); +} - if (memcg) - return &memcg->deferred_split_queue; - else - return &pgdat->deferred_split_queue; +static inline struct deferred_split *folio_memcg_split_queue(struct folio *folio) +{ + struct mem_cgroup *memcg = folio_memcg(folio); + + return memcg ? &memcg->deferred_split_queue : NULL; } #else -static inline struct deferred_split *get_deferred_split_queue(struct page *page) +static inline struct mem_cgroup *folio_split_queue_memcg(struct folio *folio, + struct deferred_split *queue) { - struct pglist_data *pgdat = NODE_DATA(page_to_nid(page)); + return NULL; +} - return &pgdat->deferred_split_queue; +static inline struct deferred_split *folio_memcg_split_queue(struct folio *folio) +{ + return NULL; } #endif +static struct deferred_split *folio_split_queue(struct folio *folio) +{ + struct deferred_split *queue = folio_memcg_split_queue(folio); + + return queue ? : &NODE_DATA(folio_nid(folio))->deferred_split_queue; +} + +static struct deferred_split *folio_split_queue_lock(struct folio *folio) +{ + struct deferred_split *queue; + + rcu_read_lock(); +retry: + queue = folio_split_queue(folio); + spin_lock(&queue->split_queue_lock); + + if (unlikely(folio_split_queue_memcg(folio, queue) != folio_memcg(folio))) { + spin_unlock(&queue->split_queue_lock); + goto retry; + } + rcu_read_unlock(); + + return queue; +} + +static struct deferred_split * +folio_split_queue_lock_irqsave(struct folio *folio, unsigned long *flags) +{ + struct deferred_split *queue; + + rcu_read_lock(); +retry: + queue = folio_split_queue(folio); + spin_lock_irqsave(&queue->split_queue_lock, *flags); + + if (unlikely(folio_split_queue_memcg(folio, queue) != folio_memcg(folio))) { + spin_unlock_irqrestore(&queue->split_queue_lock, *flags); + goto retry; + } + rcu_read_unlock(); + + return queue; +} + +static inline void split_queue_unlock(struct deferred_split *queue) +{ + spin_unlock(&queue->split_queue_lock); +} + +static inline void split_queue_unlock_irqrestore(struct deferred_split *queue, + unsigned long flags) +{ + spin_unlock_irqrestore(&queue->split_queue_lock, flags); +} + void prep_transhuge_page(struct page *page) { /* @@ -2604,7 +2669,7 @@ int split_huge_page_to_list(struct page { struct folio *folio = page_folio(page); struct page *head = &folio->page; - struct deferred_split *ds_queue = get_deferred_split_queue(head); + struct deferred_split *ds_queue; XA_STATE(xas, &head->mapping->i_pages, head->index); struct anon_vma *anon_vma = NULL; struct address_space *mapping = NULL; @@ -2696,13 +2761,13 @@ int split_huge_page_to_list(struct page } /* Prevent deferred_split_scan() touching ->_refcount */ - spin_lock(&ds_queue->split_queue_lock); + ds_queue = folio_split_queue_lock(folio); if (page_ref_freeze(head, 1 + extra_pins)) { if (!list_empty(page_deferred_list(head))) { ds_queue->split_queue_len--; list_del(page_deferred_list(head)); } - spin_unlock(&ds_queue->split_queue_lock); + split_queue_unlock(ds_queue); if (mapping) { int nr = thp_nr_pages(head); @@ -2720,7 +2785,7 @@ int split_huge_page_to_list(struct page __split_huge_page(page, list, end); ret = 0; } else { - spin_unlock(&ds_queue->split_queue_lock); + split_queue_unlock(ds_queue); fail: if (mapping) xas_unlock(&xas); @@ -2744,25 +2809,23 @@ out: void free_transhuge_page(struct page *page) { - struct deferred_split *ds_queue = get_deferred_split_queue(page); + struct deferred_split *ds_queue; unsigned long flags; - spin_lock_irqsave(&ds_queue->split_queue_lock, flags); + ds_queue = folio_split_queue_lock_irqsave(page_folio(page), &flags); if (!list_empty(page_deferred_list(page))) { ds_queue->split_queue_len--; list_del(page_deferred_list(page)); } - spin_unlock_irqrestore(&ds_queue->split_queue_lock, flags); + split_queue_unlock_irqrestore(ds_queue, flags); free_compound_page(page); } 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 = page_memcg(compound_head(page)); -#endif + struct deferred_split *ds_queue; unsigned long flags; + struct folio *folio = page_folio(page); VM_BUG_ON_PAGE(!PageTransHuge(page), page); @@ -2779,18 +2842,19 @@ void deferred_split_huge_page(struct pag if (PageSwapCache(page)) return; - spin_lock_irqsave(&ds_queue->split_queue_lock, flags); + ds_queue = folio_split_queue_lock_irqsave(folio, &flags); if (list_empty(page_deferred_list(page))) { + struct mem_cgroup *memcg; + + memcg = folio_split_queue_memcg(folio, ds_queue); count_vm_event(THP_DEFERRED_SPLIT_PAGE); list_add_tail(page_deferred_list(page), &ds_queue->split_queue); ds_queue->split_queue_len++; -#ifdef CONFIG_MEMCG if (memcg) set_shrinker_bit(memcg, page_to_nid(page), - deferred_split_shrinker.id); -#endif + shrinker_id(&deferred_split_shrinker)); } - spin_unlock_irqrestore(&ds_queue->split_queue_lock, flags); + split_queue_unlock_irqrestore(ds_queue, flags); } static unsigned long deferred_split_count(struct shrinker *shrink, _ Patches currently in -mm which might be from songmuchun@xxxxxxxxxxxxx are mm-fix-missing-wake-up-event-for-fsdax-pages.patch mm-memcontrol-make-all-the-callers-of-foliopage_memcg-safe.patch mm-memcontrol-introduce-memcg_reparent_ops.patch mm-memcontrol-use-obj_cgroup-apis-to-charge-the-lru-pages.patch mm-lru-add-vm_warn_on_once_folio-to-lru-maintenance-function.patch mm-hugetlb_vmemmap-delete-hugetlb_optimize_vmemmap_enabled.patch mm-hugetlb_vmemmap-optimize-vmemmap_optimize_mode-handling.patch mm-hugetlb_vmemmap-introduce-the-name-hvo.patch mm-hugetlb_vmemmap-move-vmemmap-code-related-to-hugetlb-to-hugetlb_vmemmapc.patch mm-hugetlb_vmemmap-replace-early_param-with-core_param.patch mm-hugetlb_vmemmap-improve-hugetlb_vmemmap-code-readability.patch mm-hugetlb_vmemmap-move-code-comments-to-vmemmap_deduprst.patch mm-hugetlb_vmemmap-use-ptrs_per_pte-instead-of-pmd_size-page_size.patch