From 3e9a13daa61253e28a1c7d8f366931e0a58a2b5a Mon Sep 17 00:00:00 2001 From: "Matthew Wilcox (Oracle)" Date: Fri, 2 Sep 2022 20:46:48 +0100 Subject: huge_memory: convert split_huge_page_to_list() to use a folio Saves many calls to compound_head(). Link: https://lkml.kernel.org/r/20220902194653.1739778-53-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) Signed-off-by: Andrew Morton --- mm/huge_memory.c | 49 ++++++++++++++++++++++++------------------------- 1 file changed, 24 insertions(+), 25 deletions(-) (limited to 'mm') diff --git a/mm/huge_memory.c b/mm/huge_memory.c index 1181e623bf5b..bb8266b099f5 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -2622,27 +2622,26 @@ bool can_split_folio(struct folio *folio, int *pextra_pins) int split_huge_page_to_list(struct page *page, struct list_head *list) { struct folio *folio = page_folio(page); - struct page *head = &folio->page; - struct deferred_split *ds_queue = get_deferred_split_queue(head); - XA_STATE(xas, &head->mapping->i_pages, head->index); + struct deferred_split *ds_queue = get_deferred_split_queue(&folio->page); + XA_STATE(xas, &folio->mapping->i_pages, folio->index); struct anon_vma *anon_vma = NULL; struct address_space *mapping = NULL; int extra_pins, ret; pgoff_t end; bool is_hzp; - VM_BUG_ON_PAGE(!PageLocked(head), head); - VM_BUG_ON_PAGE(!PageCompound(head), head); + VM_BUG_ON_FOLIO(!folio_test_locked(folio), folio); + VM_BUG_ON_FOLIO(!folio_test_large(folio), folio); - is_hzp = is_huge_zero_page(head); - VM_WARN_ON_ONCE_PAGE(is_hzp, head); + is_hzp = is_huge_zero_page(&folio->page); + VM_WARN_ON_ONCE_FOLIO(is_hzp, folio); if (is_hzp) return -EBUSY; - if (PageWriteback(head)) + if (folio_test_writeback(folio)) return -EBUSY; - if (PageAnon(head)) { + if (folio_test_anon(folio)) { /* * The caller does not necessarily hold an mmap_lock that would * prevent the anon_vma disappearing so we first we take a @@ -2651,7 +2650,7 @@ int split_huge_page_to_list(struct page *page, struct list_head *list) * is taken to serialise against parallel split or collapse * operations. */ - anon_vma = page_get_anon_vma(head); + anon_vma = page_get_anon_vma(&folio->page); if (!anon_vma) { ret = -EBUSY; goto out; @@ -2662,7 +2661,7 @@ int split_huge_page_to_list(struct page *page, struct list_head *list) } else { gfp_t gfp; - mapping = head->mapping; + mapping = folio->mapping; /* Truncated ? */ if (!mapping) { @@ -2679,7 +2678,7 @@ int split_huge_page_to_list(struct page *page, struct list_head *list) goto out; } - xas_split_alloc(&xas, head, compound_order(head), gfp); + xas_split_alloc(&xas, folio, folio_order(folio), gfp); if (xas_error(&xas)) { ret = xas_error(&xas); goto out; @@ -2693,7 +2692,7 @@ int split_huge_page_to_list(struct page *page, struct list_head *list) * but on 32-bit, i_size_read() takes an irq-unsafe seqlock, * which cannot be nested inside the page tree lock. So note * end now: i_size itself may be changed at any moment, but - * head page lock is good enough to serialize the trimming. + * folio lock is good enough to serialize the trimming. */ end = DIV_ROUND_UP(i_size_read(mapping->host), PAGE_SIZE); if (shmem_mapping(mapping)) @@ -2709,38 +2708,38 @@ int split_huge_page_to_list(struct page *page, struct list_head *list) goto out_unlock; } - unmap_page(head); + unmap_page(&folio->page); /* block interrupt reentry in xa_lock and spinlock */ local_irq_disable(); if (mapping) { /* - * Check if the head page is present in page cache. - * We assume all tail are present too, if head is there. + * Check if the folio is present in page cache. + * We assume all tail are present too, if folio is there. */ xas_lock(&xas); xas_reset(&xas); - if (xas_load(&xas) != head) + if (xas_load(&xas) != folio) goto fail; } /* Prevent deferred_split_scan() touching ->_refcount */ spin_lock(&ds_queue->split_queue_lock); - if (page_ref_freeze(head, 1 + extra_pins)) { - if (!list_empty(page_deferred_list(head))) { + if (folio_ref_freeze(folio, 1 + extra_pins)) { + if (!list_empty(page_deferred_list(&folio->page))) { ds_queue->split_queue_len--; - list_del(page_deferred_list(head)); + list_del(page_deferred_list(&folio->page)); } spin_unlock(&ds_queue->split_queue_lock); if (mapping) { - int nr = thp_nr_pages(head); + int nr = folio_nr_pages(folio); - xas_split(&xas, head, thp_order(head)); - if (PageSwapBacked(head)) { - __mod_lruvec_page_state(head, NR_SHMEM_THPS, + xas_split(&xas, folio, folio_order(folio)); + if (folio_test_swapbacked(folio)) { + __lruvec_stat_mod_folio(folio, NR_SHMEM_THPS, -nr); } else { - __mod_lruvec_page_state(head, NR_FILE_THPS, + __lruvec_stat_mod_folio(folio, NR_FILE_THPS, -nr); filemap_nr_thps_dec(mapping); } -- cgit v1.2.3