From: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
To: Hugh Dickins <hughd@google.com>,
Andrea Arcangeli <aarcange@redhat.com>,
Andrew Morton <akpm@linux-foundation.org>
Cc: Dave Hansen <dave.hansen@intel.com>,
Vlastimil Babka <vbabka@suse.cz>,
Christoph Lameter <cl@gentwo.org>,
Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>,
Jerome Marchand <jmarchan@redhat.com>,
Yang Shi <yang.shi@linaro.org>,
Sasha Levin <sasha.levin@oracle.com>,
Andres Lagar-Cavilla <andreslc@google.com>,
Ning Qu <quning@gmail.com>,
linux-kernel@vger.kernel.org, linux-mm@kvack.org,
linux-fsdevel@vger.kernel.org,
"Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Subject: [PATCHv9-rebased 15/32] thp, mlock: do not mlock PTE-mapped file huge pages
Date: Tue, 7 Jun 2016 14:00:29 +0300 [thread overview]
Message-ID: <1465297246-98985-16-git-send-email-kirill.shutemov@linux.intel.com> (raw)
In-Reply-To: <1465297246-98985-1-git-send-email-kirill.shutemov@linux.intel.com>
As with anon THP, we only mlock file huge pages if we can prove that the
page is not mapped with PTE. This way we can avoid mlock leak into
non-mlocked vma on split.
We rely on PageDoubleMap() under lock_page() to check if the the page
may be PTE mapped. PG_double_map is set by page_add_file_rmap() when the
page mapped with PTEs.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
---
include/linux/page-flags.h | 13 ++++++++++++-
mm/huge_memory.c | 27 ++++++++++++++++++++-------
mm/mmap.c | 6 ++++++
mm/page_alloc.c | 2 ++
mm/rmap.c | 16 ++++++++++++++--
5 files changed, 54 insertions(+), 10 deletions(-)
diff --git a/include/linux/page-flags.h b/include/linux/page-flags.h
index 7c8e82ac2eb7..8cf09639185a 100644
--- a/include/linux/page-flags.h
+++ b/include/linux/page-flags.h
@@ -581,6 +581,17 @@ static inline int PageDoubleMap(struct page *page)
return PageHead(page) && test_bit(PG_double_map, &page[1].flags);
}
+static inline void SetPageDoubleMap(struct page *page)
+{
+ VM_BUG_ON_PAGE(!PageHead(page), page);
+ set_bit(PG_double_map, &page[1].flags);
+}
+
+static inline void ClearPageDoubleMap(struct page *page)
+{
+ VM_BUG_ON_PAGE(!PageHead(page), page);
+ clear_bit(PG_double_map, &page[1].flags);
+}
static inline int TestSetPageDoubleMap(struct page *page)
{
VM_BUG_ON_PAGE(!PageHead(page), page);
@@ -598,7 +609,7 @@ TESTPAGEFLAG_FALSE(TransHuge)
TESTPAGEFLAG_FALSE(TransCompound)
TESTPAGEFLAG_FALSE(TransCompoundMap)
TESTPAGEFLAG_FALSE(TransTail)
-TESTPAGEFLAG_FALSE(DoubleMap)
+PAGEFLAG_FALSE(DoubleMap)
TESTSETFLAG_FALSE(DoubleMap)
TESTCLEARFLAG_FALSE(DoubleMap)
#endif
diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index b3b2bf3da167..28e7d963cc1f 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -1438,6 +1438,8 @@ struct page *follow_trans_huge_pmd(struct vm_area_struct *vma,
* We don't mlock() pte-mapped THPs. This way we can avoid
* leaking mlocked pages into non-VM_LOCKED VMAs.
*
+ * For anon THP:
+ *
* In most cases the pmd is the only mapping of the page as we
* break COW for the mlock() -- see gup_flags |= FOLL_WRITE for
* writable private mappings in populate_vma_page_range().
@@ -1445,15 +1447,26 @@ struct page *follow_trans_huge_pmd(struct vm_area_struct *vma,
* The only scenario when we have the page shared here is if we
* mlocking read-only mapping shared over fork(). We skip
* mlocking such pages.
+ *
+ * For file THP:
+ *
+ * We can expect PageDoubleMap() to be stable under page lock:
+ * for file pages we set it in page_add_file_rmap(), which
+ * requires page to be locked.
*/
- if (compound_mapcount(page) == 1 && !PageDoubleMap(page) &&
- page->mapping && trylock_page(page)) {
- lru_add_drain();
- if (page->mapping)
- mlock_vma_page(page);
- unlock_page(page);
- }
+
+ if (PageAnon(page) && compound_mapcount(page) != 1)
+ goto skip_mlock;
+ if (PageDoubleMap(page) || !page->mapping)
+ goto skip_mlock;
+ if (!trylock_page(page))
+ goto skip_mlock;
+ lru_add_drain();
+ if (page->mapping && !PageDoubleMap(page))
+ mlock_vma_page(page);
+ unlock_page(page);
}
+skip_mlock:
page += (addr & ~HPAGE_PMD_MASK) >> PAGE_SHIFT;
VM_BUG_ON_PAGE(!PageCompound(page), page);
if (flags & FOLL_GET)
diff --git a/mm/mmap.c b/mm/mmap.c
index 02990e7dd70e..daabef097c78 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -2591,6 +2591,12 @@ SYSCALL_DEFINE5(remap_file_pages, unsigned long, start, unsigned long, size,
/* drop PG_Mlocked flag for over-mapped range */
for (tmp = vma; tmp->vm_start >= start + size;
tmp = tmp->vm_next) {
+ /*
+ * Split pmd and munlock page on the border
+ * of the range.
+ */
+ vma_adjust_trans_huge(tmp, start, start + size, 0);
+
munlock_vma_pages_range(tmp,
max(tmp->vm_start, start),
min(tmp->vm_end, start + size));
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index a46547389e53..e32ff3abe9da 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -1005,6 +1005,8 @@ static __always_inline bool free_pages_prepare(struct page *page,
VM_BUG_ON_PAGE(compound && compound_order(page) != order, page);
+ if (compound)
+ ClearPageDoubleMap(page);
for (i = 1; i < (1 << order); i++) {
if (compound)
bad += free_tail_pages_check(page, page + i);
diff --git a/mm/rmap.c b/mm/rmap.c
index b78374519bac..26e3e784ad75 100644
--- a/mm/rmap.c
+++ b/mm/rmap.c
@@ -1287,6 +1287,12 @@ void page_add_file_rmap(struct page *page, bool compound)
if (!atomic_inc_and_test(compound_mapcount_ptr(page)))
goto out;
} else {
+ if (PageTransCompound(page)) {
+ VM_BUG_ON_PAGE(!PageLocked(page), page);
+ SetPageDoubleMap(compound_head(page));
+ if (PageMlocked(page))
+ clear_page_mlock(compound_head(page));
+ }
if (!atomic_inc_and_test(&page->_mapcount))
goto out;
}
@@ -1460,8 +1466,14 @@ static int try_to_unmap_one(struct page *page, struct vm_area_struct *vma,
*/
if (!(flags & TTU_IGNORE_MLOCK)) {
if (vma->vm_flags & VM_LOCKED) {
- /* Holding pte lock, we do *not* need mmap_sem here */
- mlock_vma_page(page);
+ /* PTE-mapped THP are never mlocked */
+ if (!PageTransCompound(page)) {
+ /*
+ * Holding pte lock, we do *not* need
+ * mmap_sem here
+ */
+ mlock_vma_page(page);
+ }
ret = SWAP_MLOCK;
goto out_unmap;
}
--
2.8.1
next prev parent reply other threads:[~2016-06-07 11:11 UTC|newest]
Thread overview: 108+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-06-06 14:06 [PATCHv9 00/32] THP-enabled tmpfs/shmem using compound pages Kirill A. Shutemov
2016-06-06 14:06 ` [PATCHv9 01/32] thp, mlock: update unevictable-lru.txt Kirill A. Shutemov
2016-06-06 14:06 ` [PATCHv9 02/32] mm: do not pass mm_struct into handle_mm_fault Kirill A. Shutemov
2016-06-06 14:06 ` [PATCHv9 03/32] mm: introduce fault_env Kirill A. Shutemov
2016-06-06 14:06 ` [PATCHv9 04/32] mm: postpone page table allocation until we have page to map Kirill A. Shutemov
2016-06-06 14:06 ` [PATCHv9 05/32] rmap: support file thp Kirill A. Shutemov
2016-06-06 14:06 ` [PATCHv9 06/32] mm: introduce do_set_pmd() Kirill A. Shutemov
2016-06-06 14:06 ` [PATCHv9 07/32] thp, vmstats: add counters for huge file pages Kirill A. Shutemov
2016-06-06 14:06 ` [PATCHv9 08/32] thp: support file pages in zap_huge_pmd() Kirill A. Shutemov
2016-06-06 14:06 ` [PATCHv9 09/32] thp: handle file pages in split_huge_pmd() Kirill A. Shutemov
2016-06-06 14:06 ` [PATCHv9 10/32] thp: handle file COW faults Kirill A. Shutemov
2016-06-06 14:06 ` [PATCHv9 11/32] thp: skip file huge pmd on copy_huge_pmd() Kirill A. Shutemov
2016-06-06 14:06 ` [PATCHv9 12/32] thp: prepare change_huge_pmd() for file thp Kirill A. Shutemov
2016-06-06 14:06 ` [PATCHv9 13/32] thp: run vma_adjust_trans_huge() outside i_mmap_rwsem Kirill A. Shutemov
2016-06-06 14:06 ` [PATCHv9 14/32] thp: file pages support for split_huge_page() Kirill A. Shutemov
2016-06-06 14:06 ` [PATCHv9 15/32] thp, mlock: do not mlock PTE-mapped file huge pages Kirill A. Shutemov
2016-06-06 14:06 ` [PATCHv9 16/32] vmscan: split file huge pages before paging them out Kirill A. Shutemov
2016-06-06 14:06 ` [PATCHv9 17/32] page-flags: relax policy for PG_mappedtodisk and PG_reclaim Kirill A. Shutemov
2016-06-06 14:06 ` [PATCHv9 18/32] radix-tree: implement radix_tree_maybe_preload_order() Kirill A. Shutemov
2016-06-06 14:06 ` [PATCHv9 19/32] filemap: prepare find and delete operations for huge pages Kirill A. Shutemov
2016-06-06 14:06 ` [PATCHv9 20/32] truncate: handle file thp Kirill A. Shutemov
2016-06-06 14:06 ` [PATCHv9 21/32] mm, rmap: account shmem thp pages Kirill A. Shutemov
2016-06-06 14:06 ` [PATCHv9 22/32] shmem: prepare huge= mount option and sysfs knob Kirill A. Shutemov
2016-06-06 14:07 ` [PATCHv9 23/32] shmem: get_unmapped_area align huge page Kirill A. Shutemov
2016-06-06 14:07 ` [PATCHv9 24/32] shmem: add huge pages support Kirill A. Shutemov
2016-06-06 14:07 ` [PATCHv9 25/32] shmem, thp: respect MADV_{NO,}HUGEPAGE for file mappings Kirill A. Shutemov
2016-06-06 14:07 ` [PATCHv9 26/32] thp: extract khugepaged from mm/huge_memory.c Kirill A. Shutemov
2016-06-06 14:07 ` [PATCHv9 27/32] khugepaged: move up_read(mmap_sem) out of khugepaged_alloc_page() Kirill A. Shutemov
2016-06-06 14:07 ` [PATCHv9 28/32] shmem: make shmem_inode_info::lock irq-safe Kirill A. Shutemov
2016-06-06 14:07 ` [PATCHv9 29/32] khugepaged: add support of collapse for tmpfs/shmem pages Kirill A. Shutemov
2016-06-06 14:07 ` [PATCHv9 30/32] thp: introduce CONFIG_TRANSPARENT_HUGE_PAGECACHE Kirill A. Shutemov
2016-06-06 14:07 ` [PATCHv9 31/32] shmem: split huge pages beyond i_size under memory pressure Kirill A. Shutemov
2016-06-06 14:07 ` [PATCHv9 32/32] thp: update Documentation/{vm/transhuge,filesystems/proc}.txt Kirill A. Shutemov
2016-06-07 11:00 ` [PATCHv9-rebased 00/32] THP-enabled tmpfs/shmem using compound pages Kirill A. Shutemov
2016-06-07 11:00 ` [PATCHv9-rebased 01/32] thp, mlock: update unevictable-lru.txt Kirill A. Shutemov
2016-06-07 11:00 ` [PATCHv9-rebased 02/32] mm: do not pass mm_struct into handle_mm_fault Kirill A. Shutemov
2016-06-07 11:00 ` [PATCHv9-rebased 03/32] mm: introduce fault_env Kirill A. Shutemov
2016-06-07 11:00 ` [PATCHv9-rebased 04/32] mm: postpone page table allocation until we have page to map Kirill A. Shutemov
2016-06-07 11:00 ` [PATCHv9-rebased 05/32] rmap: support file thp Kirill A. Shutemov
2016-06-07 11:00 ` [PATCHv9-rebased 06/32] mm: introduce do_set_pmd() Kirill A. Shutemov
2016-06-07 11:00 ` [PATCHv9-rebased 07/32] thp, vmstats: add counters for huge file pages Kirill A. Shutemov
2016-06-07 11:00 ` [PATCHv9-rebased 08/32] thp: support file pages in zap_huge_pmd() Kirill A. Shutemov
2016-06-07 11:00 ` [PATCHv9-rebased 09/32] thp: handle file pages in split_huge_pmd() Kirill A. Shutemov
2016-06-07 11:00 ` [PATCHv9-rebased 10/32] thp: handle file COW faults Kirill A. Shutemov
2016-06-07 11:00 ` [PATCHv9-rebased 11/32] thp: skip file huge pmd on copy_huge_pmd() Kirill A. Shutemov
2016-06-07 11:00 ` [PATCHv9-rebased 12/32] thp: prepare change_huge_pmd() for file thp Kirill A. Shutemov
2016-06-07 11:00 ` [PATCHv9-rebased 13/32] thp: run vma_adjust_trans_huge() outside i_mmap_rwsem Kirill A. Shutemov
2016-06-07 11:00 ` [PATCHv9-rebased 14/32] thp: file pages support for split_huge_page() Kirill A. Shutemov
2016-06-07 11:00 ` Kirill A. Shutemov [this message]
2016-06-07 11:00 ` [PATCHv9-rebased 16/32] vmscan: split file huge pages before paging them out Kirill A. Shutemov
2016-06-07 11:00 ` [PATCHv9-rebased 17/32] page-flags: relax policy for PG_mappedtodisk and PG_reclaim Kirill A. Shutemov
2016-06-07 11:00 ` [PATCHv9-rebased 18/32] radix-tree: implement radix_tree_maybe_preload_order() Kirill A. Shutemov
2016-06-07 11:00 ` [PATCHv9-rebased 19/32] filemap: prepare find and delete operations for huge pages Kirill A. Shutemov
2016-06-07 11:00 ` [PATCHv9-rebased 20/32] truncate: handle file thp Kirill A. Shutemov
2016-06-07 11:00 ` [PATCHv9-rebased 21/32] mm, rmap: account shmem thp pages Kirill A. Shutemov
2016-06-07 11:00 ` [PATCHv9-rebased 22/32] shmem: prepare huge= mount option and sysfs knob Kirill A. Shutemov
2016-06-07 11:00 ` [PATCHv9-rebased 23/32] shmem: get_unmapped_area align huge page Kirill A. Shutemov
2016-06-07 11:00 ` [PATCHv9-rebased 24/32] shmem: add huge pages support Kirill A. Shutemov
2016-06-07 11:00 ` [PATCHv9-rebased 25/32] shmem, thp: respect MADV_{NO,}HUGEPAGE for file mappings Kirill A. Shutemov
2016-06-07 11:00 ` [PATCHv9-rebased 26/32] thp: extract khugepaged from mm/huge_memory.c Kirill A. Shutemov
2016-06-07 11:00 ` [PATCHv9-rebased 27/32] khugepaged: move up_read(mmap_sem) out of khugepaged_alloc_page() Kirill A. Shutemov
2016-06-07 11:00 ` [PATCHv9-rebased 28/32] shmem: make shmem_inode_info::lock irq-safe Kirill A. Shutemov
2016-06-07 11:00 ` [PATCHv9-rebased 29/32] khugepaged: add support of collapse for tmpfs/shmem pages Kirill A. Shutemov
2016-06-07 11:00 ` [PATCHv9-rebased 30/32] thp: introduce CONFIG_TRANSPARENT_HUGE_PAGECACHE Kirill A. Shutemov
2016-06-07 11:00 ` [PATCHv9-rebased 31/32] shmem: split huge pages beyond i_size under memory pressure Kirill A. Shutemov
2016-06-07 11:00 ` [PATCHv9-rebased 32/32] thp: update Documentation/{vm/transhuge,filesystems/proc}.txt Kirill A. Shutemov
2016-06-15 20:06 ` [PATCHv9-rebased2 00/37] THP-enabled tmpfs/shmem using compound pages Kirill A. Shutemov
2016-06-15 20:06 ` [PATCHv9-rebased2 01/37] mm, thp: make swapin readahead under down_read of mmap_sem Kirill A. Shutemov
2016-06-15 20:06 ` [PATCHv9-rebased2 02/37] mm-thp-make-swapin-readahead-under-down_read-of-mmap_sem-fix Kirill A. Shutemov
2016-06-15 20:06 ` [PATCHv9-rebased2 03/37] mm, thp: fix locking inconsistency in collapse_huge_page Kirill A. Shutemov
2016-06-16 0:43 ` Sergey Senozhatsky
2016-06-16 8:02 ` Kirill A. Shutemov
2016-06-15 20:06 ` [PATCHv9-rebased2 04/37] mm-thp-make-swapin-readahead-under-down_read-of-mmap_sem-fix-2-fix Kirill A. Shutemov
2016-06-15 20:06 ` [PATCHv9-rebased2 05/37] khugepaged: recheck pmd after mmap_sem re-acquired Kirill A. Shutemov
2016-06-16 11:47 ` Ebru Akagunduz
2016-06-16 11:51 ` Kirill A. Shutemov
2016-06-15 20:06 ` [PATCHv9-rebased2 06/37] thp, mlock: update unevictable-lru.txt Kirill A. Shutemov
2016-06-15 20:06 ` [PATCHv9-rebased2 07/37] mm: do not pass mm_struct into handle_mm_fault Kirill A. Shutemov
2016-06-15 20:06 ` [PATCHv9-rebased2 08/37] mm: introduce fault_env Kirill A. Shutemov
2016-06-15 20:06 ` [PATCHv9-rebased2 09/37] mm: postpone page table allocation until we have page to map Kirill A. Shutemov
2016-06-15 20:06 ` [PATCHv9-rebased2 10/37] rmap: support file thp Kirill A. Shutemov
2016-06-15 20:06 ` [PATCHv9-rebased2 11/37] mm: introduce do_set_pmd() Kirill A. Shutemov
2016-06-15 20:06 ` [PATCHv9-rebased2 12/37] thp, vmstats: add counters for huge file pages Kirill A. Shutemov
2016-06-15 20:06 ` [PATCHv9-rebased2 13/37] thp: support file pages in zap_huge_pmd() Kirill A. Shutemov
2016-06-15 20:06 ` [PATCHv9-rebased2 14/37] thp: handle file pages in split_huge_pmd() Kirill A. Shutemov
2016-06-15 20:06 ` [PATCHv9-rebased2 15/37] thp: handle file COW faults Kirill A. Shutemov
2016-06-15 20:06 ` [PATCHv9-rebased2 16/37] thp: skip file huge pmd on copy_huge_pmd() Kirill A. Shutemov
2016-06-15 20:06 ` [PATCHv9-rebased2 17/37] thp: prepare change_huge_pmd() for file thp Kirill A. Shutemov
2016-06-15 20:06 ` [PATCHv9-rebased2 18/37] thp: run vma_adjust_trans_huge() outside i_mmap_rwsem Kirill A. Shutemov
2016-06-15 20:06 ` [PATCHv9-rebased2 19/37] thp: file pages support for split_huge_page() Kirill A. Shutemov
2016-06-15 20:06 ` [PATCHv9-rebased2 20/37] thp, mlock: do not mlock PTE-mapped file huge pages Kirill A. Shutemov
2016-06-15 20:06 ` [PATCHv9-rebased2 21/37] vmscan: split file huge pages before paging them out Kirill A. Shutemov
2016-06-15 20:06 ` [PATCHv9-rebased2 22/37] page-flags: relax policy for PG_mappedtodisk and PG_reclaim Kirill A. Shutemov
2016-06-15 20:06 ` [PATCHv9-rebased2 23/37] radix-tree: implement radix_tree_maybe_preload_order() Kirill A. Shutemov
2016-06-15 20:06 ` [PATCHv9-rebased2 24/37] filemap: prepare find and delete operations for huge pages Kirill A. Shutemov
2016-06-15 20:06 ` [PATCHv9-rebased2 25/37] truncate: handle file thp Kirill A. Shutemov
2016-06-15 20:06 ` [PATCHv9-rebased2 26/37] mm, rmap: account shmem thp pages Kirill A. Shutemov
2016-06-15 20:06 ` [PATCHv9-rebased2 27/37] shmem: prepare huge= mount option and sysfs knob Kirill A. Shutemov
2016-06-15 20:06 ` [PATCHv9-rebased2 28/37] shmem: get_unmapped_area align huge page Kirill A. Shutemov
2016-06-15 20:06 ` [PATCHv9-rebased2 29/37] shmem: add huge pages support Kirill A. Shutemov
2016-06-15 20:06 ` [PATCHv9-rebased2 30/37] shmem, thp: respect MADV_{NO,}HUGEPAGE for file mappings Kirill A. Shutemov
2016-06-15 20:06 ` [PATCHv9-rebased2 31/37] thp: extract khugepaged from mm/huge_memory.c Kirill A. Shutemov
2016-06-15 20:06 ` [PATCHv9-rebased2 32/37] khugepaged: move up_read(mmap_sem) out of khugepaged_alloc_page() Kirill A. Shutemov
2016-06-15 20:06 ` [PATCHv9-rebased2 33/37] shmem: make shmem_inode_info::lock irq-safe Kirill A. Shutemov
2016-06-15 20:06 ` [PATCHv9-rebased2 34/37] khugepaged: add support of collapse for tmpfs/shmem pages Kirill A. Shutemov
2016-06-15 20:06 ` [PATCHv9-rebased2 35/37] thp: introduce CONFIG_TRANSPARENT_HUGE_PAGECACHE Kirill A. Shutemov
2016-06-15 20:06 ` [PATCHv9-rebased2 36/37] shmem: split huge pages beyond i_size under memory pressure Kirill A. Shutemov
2016-06-15 20:06 ` [PATCHv9-rebased2 37/37] thp: update Documentation/{vm/transhuge,filesystems/proc}.txt Kirill A. Shutemov
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