diff options
Diffstat (limited to 'mm/rmap.c')
| -rw-r--r-- | mm/rmap.c | 36 |
1 files changed, 32 insertions, 4 deletions
diff --git a/mm/rmap.c b/mm/rmap.c index cdc2a885a4cd..68af2e32f7ed 100644 --- a/mm/rmap.c +++ b/mm/rmap.c @@ -1411,6 +1411,11 @@ void page_remove_rmap(struct page *page, bool compound) */ } +struct rmap_private { + enum ttu_flags flags; + int lazyfreed; +}; + /* * @arg: enum ttu_flags will be passed to this argument */ @@ -1422,7 +1427,8 @@ static int try_to_unmap_one(struct page *page, struct vm_area_struct *vma, pte_t pteval; spinlock_t *ptl; int ret = SWAP_AGAIN; - enum ttu_flags flags = (enum ttu_flags)arg; + struct rmap_private *rp = arg; + enum ttu_flags flags = rp->flags; /* munlock has nothing to gain from examining un-locked vmas */ if ((flags & TTU_MUNLOCK) && !(vma->vm_flags & VM_LOCKED)) @@ -1514,6 +1520,14 @@ static int try_to_unmap_one(struct page *page, struct vm_area_struct *vma, * See handle_pte_fault() ... */ VM_BUG_ON_PAGE(!PageSwapCache(page), page); + + if (!PageDirty(page) && (flags & TTU_LZFREE)) { + /* It's a freeable page by MADV_FREE */ + dec_mm_counter(mm, MM_ANONPAGES); + rp->lazyfreed++; + goto discard; + } + if (swap_duplicate(entry) < 0) { set_pte_at(mm, address, pte, pteval); ret = SWAP_FAIL; @@ -1534,6 +1548,7 @@ static int try_to_unmap_one(struct page *page, struct vm_area_struct *vma, } else dec_mm_counter(mm, mm_counter_file(page)); +discard: page_remove_rmap(page, PageHuge(page)); page_cache_release(page); @@ -1586,9 +1601,14 @@ static int page_not_mapped(struct page *page) int try_to_unmap(struct page *page, enum ttu_flags flags) { int ret; + struct rmap_private rp = { + .flags = flags, + .lazyfreed = 0, + }; + struct rmap_walk_control rwc = { .rmap_one = try_to_unmap_one, - .arg = (void *)flags, + .arg = &rp, .done = page_not_mapped, .anon_lock = page_lock_anon_vma_read, }; @@ -1608,8 +1628,11 @@ int try_to_unmap(struct page *page, enum ttu_flags flags) ret = rmap_walk(page, &rwc); - if (ret != SWAP_MLOCK && !page_mapped(page)) + if (ret != SWAP_MLOCK && !page_mapped(page)) { ret = SWAP_SUCCESS; + if (rp.lazyfreed && !PageDirty(page)) + ret = SWAP_LZFREE; + } return ret; } @@ -1631,9 +1654,14 @@ int try_to_unmap(struct page *page, enum ttu_flags flags) int try_to_munlock(struct page *page) { int ret; + struct rmap_private rp = { + .flags = TTU_MUNLOCK, + .lazyfreed = 0, + }; + struct rmap_walk_control rwc = { .rmap_one = try_to_unmap_one, - .arg = (void *)TTU_MUNLOCK, + .arg = &rp, .done = page_not_mapped, .anon_lock = page_lock_anon_vma_read, |