Generalize the order of the collapse_file() function to support future shmem mTHP collapse.
No functional changes in this patch. Signed-off-by: Baolin Wang <[email protected]> --- mm/khugepaged.c | 27 +++++++++++++++------------ 1 file changed, 15 insertions(+), 12 deletions(-) diff --git a/mm/khugepaged.c b/mm/khugepaged.c index 631459172e19..4adc8c6de062 100644 --- a/mm/khugepaged.c +++ b/mm/khugepaged.c @@ -2214,6 +2214,7 @@ static void retract_page_tables(struct address_space *mapping, pgoff_t pgoff) * @file: file that collapse on * @start: collapse start address * @cc: collapse context and scratchpad + * @order: folio order being collapsed to * * Basic scheme is simple, details are more complex: * - allocate and lock a new huge page; @@ -2232,15 +2233,17 @@ static void retract_page_tables(struct address_space *mapping, pgoff_t pgoff) * + unlock and free huge page; */ static enum scan_result collapse_file(struct mm_struct *mm, unsigned long addr, - struct file *file, pgoff_t start, struct collapse_control *cc) + struct file *file, pgoff_t start, struct collapse_control *cc, + int order) { - const unsigned int max_ptes_none = collapse_max_ptes_none(cc, NULL, HPAGE_PMD_ORDER); + const unsigned int max_ptes_none = collapse_max_ptes_none(cc, NULL, order); struct address_space *mapping = file->f_mapping; + const unsigned long nr_pages = 1UL << order; struct page *dst; struct folio *folio, *tmp, *new_folio; - pgoff_t index = 0, end = start + HPAGE_PMD_NR; + pgoff_t index = 0, end = start + nr_pages; LIST_HEAD(pagelist); - XA_STATE_ORDER(xas, &mapping->i_pages, start, HPAGE_PMD_ORDER); + XA_STATE_ORDER(xas, &mapping->i_pages, start, order); enum scan_result result = SCAN_SUCCEED; int nr_none = 0; bool is_shmem = shmem_file(file); @@ -2252,9 +2255,9 @@ static enum scan_result collapse_file(struct mm_struct *mm, unsigned long addr, * mapping, the shmem check can be removed. */ VM_WARN_ON_ONCE(!is_shmem && !mapping_pmd_folio_support(mapping)); - VM_WARN_ON_ONCE(start & (HPAGE_PMD_NR - 1)); + VM_WARN_ON_ONCE(start & (nr_pages - 1)); - result = alloc_charge_folio(&new_folio, mm, cc, HPAGE_PMD_ORDER); + result = alloc_charge_folio(&new_folio, mm, cc, order); if (result != SCAN_SUCCEED) goto out; @@ -2591,12 +2594,12 @@ static enum scan_result collapse_file(struct mm_struct *mm, unsigned long addr, } if (is_shmem) { - lruvec_stat_mod_folio(new_folio, NR_SHMEM, HPAGE_PMD_NR); + lruvec_stat_mod_folio(new_folio, NR_SHMEM, nr_pages); lruvec_stat_mod_folio(new_folio, NR_SHMEM_THPS, HPAGE_PMD_NR); } else { lruvec_stat_mod_folio(new_folio, NR_FILE_THPS, HPAGE_PMD_NR); } - lruvec_stat_mod_folio(new_folio, NR_FILE_PAGES, HPAGE_PMD_NR); + lruvec_stat_mod_folio(new_folio, NR_FILE_PAGES, nr_pages); /* * Mark new_folio as uptodate before inserting it into the @@ -2604,14 +2607,14 @@ static enum scan_result collapse_file(struct mm_struct *mm, unsigned long addr, * unwritten page. */ folio_mark_uptodate(new_folio); - folio_ref_add(new_folio, HPAGE_PMD_NR - 1); + folio_ref_add(new_folio, nr_pages - 1); if (is_shmem) folio_mark_dirty(new_folio); folio_add_lru(new_folio); /* Join all the small entries into a single multi-index entry. */ - xas_set_order(&xas, start, HPAGE_PMD_ORDER); + xas_set_order(&xas, start, order); xas_store(&xas, new_folio); WARN_ON_ONCE(xas_error(&xas)); xas_unlock_irq(&xas); @@ -2666,7 +2669,7 @@ static enum scan_result collapse_file(struct mm_struct *mm, unsigned long addr, folio_put(new_folio); out: VM_BUG_ON(!list_empty(&pagelist)); - trace_mm_khugepaged_collapse_file(mm, new_folio, index, addr, is_shmem, file, HPAGE_PMD_NR, result); + trace_mm_khugepaged_collapse_file(mm, new_folio, index, addr, is_shmem, file, nr_pages, result); return result; } @@ -2769,7 +2772,7 @@ static enum scan_result collapse_scan_file(struct mm_struct *mm, result = SCAN_EXCEED_NONE_PTE; count_vm_event(THP_SCAN_EXCEED_NONE_PTE); } else { - result = collapse_file(mm, addr, file, start, cc); + result = collapse_file(mm, addr, file, start, cc, HPAGE_PMD_ORDER); } } -- 2.47.3
