diff options
Diffstat (limited to 'mm/page_idle.c')
| -rw-r--r-- | mm/page_idle.c | 79 |
1 files changed, 42 insertions, 37 deletions
diff --git a/mm/page_idle.c b/mm/page_idle.c index bc08332a609c..96bb94c7b6c3 100644 --- a/mm/page_idle.c +++ b/mm/page_idle.c @@ -31,19 +31,22 @@ * * This function tries to get a user memory page by pfn as described above. */ -static struct page *page_idle_get_page(unsigned long pfn) +static struct folio *page_idle_get_folio(unsigned long pfn) { struct page *page = pfn_to_online_page(pfn); + struct folio *folio; - if (!page || !PageLRU(page) || - !get_page_unless_zero(page)) + if (!page || PageTail(page)) return NULL; - if (unlikely(!PageLRU(page))) { - put_page(page); - page = NULL; + folio = page_folio(page); + if (!folio_test_lru(folio) || !folio_try_get(folio)) + return NULL; + if (unlikely(page_folio(page) != folio || !folio_test_lru(folio))) { + folio_put(folio); + folio = NULL; } - return page; + return folio; } static bool page_idle_clear_pte_refs_one(struct folio *folio, @@ -59,12 +62,20 @@ static bool page_idle_clear_pte_refs_one(struct folio *folio, /* * For PTE-mapped THP, one sub page is referenced, * the whole THP is referenced. + * + * PFN swap PTEs, such as device-exclusive ones, that + * actually map pages are "old" from a CPU perspective. + * The MMU notifier takes care of any device aspects. */ - if (ptep_clear_young_notify(vma, addr, pvmw.pte)) - referenced = true; + if (likely(pte_present(ptep_get(pvmw.pte)))) + referenced |= ptep_test_and_clear_young(vma, addr, pvmw.pte); + referenced |= mmu_notifier_clear_young(vma->vm_mm, addr, addr + PAGE_SIZE); } else if (IS_ENABLED(CONFIG_TRANSPARENT_HUGEPAGE)) { - if (pmdp_clear_young_notify(vma, addr, pvmw.pmd)) - referenced = true; + pmd_t pmdval = pmdp_get(pvmw.pmd); + + if (likely(pmd_present(pmdval))) + referenced |= pmdp_clear_young_notify(vma, addr, pvmw.pmd); + referenced |= mmu_notifier_clear_young(vma->vm_mm, addr, addr + PMD_SIZE); } else { /* unexpected pmd-mapped page? */ WARN_ON_ONCE(1); @@ -83,10 +94,8 @@ static bool page_idle_clear_pte_refs_one(struct folio *folio, return true; } -static void page_idle_clear_pte_refs(struct page *page) +static void page_idle_clear_pte_refs(struct folio *folio) { - struct folio *folio = page_folio(page); - /* * Since rwc.try_lock is unused, rwc is effectively immutable, so we * can make it static to save some cycles and stack. @@ -95,27 +104,23 @@ static void page_idle_clear_pte_refs(struct page *page) .rmap_one = page_idle_clear_pte_refs_one, .anon_lock = folio_lock_anon_vma_read, }; - bool need_lock; if (!folio_mapped(folio) || !folio_raw_mapping(folio)) return; - need_lock = !folio_test_anon(folio) || folio_test_ksm(folio); - if (need_lock && !folio_trylock(folio)) + if (!folio_trylock(folio)) return; rmap_walk(folio, &rwc); - - if (need_lock) - folio_unlock(folio); + folio_unlock(folio); } static ssize_t page_idle_bitmap_read(struct file *file, struct kobject *kobj, - struct bin_attribute *attr, char *buf, + const struct bin_attribute *attr, char *buf, loff_t pos, size_t count) { u64 *out = (u64 *)buf; - struct page *page; + struct folio *folio; unsigned long pfn, end_pfn; int bit; @@ -134,19 +139,19 @@ static ssize_t page_idle_bitmap_read(struct file *file, struct kobject *kobj, bit = pfn % BITMAP_CHUNK_BITS; if (!bit) *out = 0ULL; - page = page_idle_get_page(pfn); - if (page) { - if (page_is_idle(page)) { + folio = page_idle_get_folio(pfn); + if (folio) { + if (folio_test_idle(folio)) { /* * The page might have been referenced via a * pte, in which case it is not idle. Clear * refs and recheck. */ - page_idle_clear_pte_refs(page); - if (page_is_idle(page)) + page_idle_clear_pte_refs(folio); + if (folio_test_idle(folio)) *out |= 1ULL << bit; } - put_page(page); + folio_put(folio); } if (bit == BITMAP_CHUNK_BITS - 1) out++; @@ -156,11 +161,11 @@ static ssize_t page_idle_bitmap_read(struct file *file, struct kobject *kobj, } static ssize_t page_idle_bitmap_write(struct file *file, struct kobject *kobj, - struct bin_attribute *attr, char *buf, + const struct bin_attribute *attr, char *buf, loff_t pos, size_t count) { const u64 *in = (u64 *)buf; - struct page *page; + struct folio *folio; unsigned long pfn, end_pfn; int bit; @@ -178,11 +183,11 @@ static ssize_t page_idle_bitmap_write(struct file *file, struct kobject *kobj, for (; pfn < end_pfn; pfn++) { bit = pfn % BITMAP_CHUNK_BITS; if ((*in >> bit) & 1) { - page = page_idle_get_page(pfn); - if (page) { - page_idle_clear_pte_refs(page); - set_page_idle(page); - put_page(page); + folio = page_idle_get_folio(pfn); + if (folio) { + page_idle_clear_pte_refs(folio); + folio_set_idle(folio); + folio_put(folio); } } if (bit == BITMAP_CHUNK_BITS - 1) @@ -192,11 +197,11 @@ static ssize_t page_idle_bitmap_write(struct file *file, struct kobject *kobj, return (char *)in - buf; } -static struct bin_attribute page_idle_bitmap_attr = +static const struct bin_attribute page_idle_bitmap_attr = __BIN_ATTR(bitmap, 0600, page_idle_bitmap_read, page_idle_bitmap_write, 0); -static struct bin_attribute *page_idle_bin_attrs[] = { +static const struct bin_attribute *const page_idle_bin_attrs[] = { &page_idle_bitmap_attr, NULL, }; |