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 25/32] shmem, thp: respect MADV_{NO,}HUGEPAGE for file mappings
Date: Tue, 7 Jun 2016 14:00:39 +0300 [thread overview]
Message-ID: <1465297246-98985-26-git-send-email-kirill.shutemov@linux.intel.com> (raw)
In-Reply-To: <1465297246-98985-1-git-send-email-kirill.shutemov@linux.intel.com>
Let's wire up existing madvise() hugepage hints for file mappings.
MADV_HUGEPAGE advise shmem to allocate huge page on page fault in the
VMA. It only has effect if the filesystem is mounted with huge=advise or
huge=within_size.
MADV_NOHUGEPAGE prevents hugepage from being allocated on page fault in
the VMA. It doesn't prevent a huge page from being allocated by other
means, i.e. page fault into different mapping or write(2) into file.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
---
mm/huge_memory.c | 19 +++++--------------
mm/shmem.c | 20 +++++++++++++++++---
2 files changed, 22 insertions(+), 17 deletions(-)
diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index d6235287f077..abf12f376c36 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -1836,7 +1836,7 @@ spinlock_t *__pmd_trans_huge_lock(pmd_t *pmd, struct vm_area_struct *vma)
return NULL;
}
-#define VM_NO_THP (VM_SPECIAL | VM_HUGETLB | VM_SHARED | VM_MAYSHARE)
+#define VM_NO_KHUGEPAGED (VM_SPECIAL | VM_HUGETLB | VM_SHARED | VM_MAYSHARE)
int hugepage_madvise(struct vm_area_struct *vma,
unsigned long *vm_flags, int advice)
@@ -1852,11 +1852,6 @@ int hugepage_madvise(struct vm_area_struct *vma,
if (mm_has_pgste(vma->vm_mm))
return 0;
#endif
- /*
- * Be somewhat over-protective like KSM for now!
- */
- if (*vm_flags & VM_NO_THP)
- return -EINVAL;
*vm_flags &= ~VM_NOHUGEPAGE;
*vm_flags |= VM_HUGEPAGE;
/*
@@ -1864,15 +1859,11 @@ int hugepage_madvise(struct vm_area_struct *vma,
* register it here without waiting a page fault that
* may not happen any time soon.
*/
- if (unlikely(khugepaged_enter_vma_merge(vma, *vm_flags)))
+ if (!(*vm_flags & VM_NO_KHUGEPAGED) &&
+ khugepaged_enter_vma_merge(vma, *vm_flags))
return -ENOMEM;
break;
case MADV_NOHUGEPAGE:
- /*
- * Be somewhat over-protective like KSM for now!
- */
- if (*vm_flags & VM_NO_THP)
- return -EINVAL;
*vm_flags &= ~VM_HUGEPAGE;
*vm_flags |= VM_NOHUGEPAGE;
/*
@@ -1979,7 +1970,7 @@ int khugepaged_enter_vma_merge(struct vm_area_struct *vma,
* page fault if needed.
*/
return 0;
- if (vma->vm_ops || (vm_flags & VM_NO_THP))
+ if (vma->vm_ops || (vm_flags & VM_NO_KHUGEPAGED))
/* khugepaged not yet working on file or special mappings */
return 0;
hstart = (vma->vm_start + ~HPAGE_PMD_MASK) & HPAGE_PMD_MASK;
@@ -2378,7 +2369,7 @@ static bool hugepage_vma_check(struct vm_area_struct *vma)
return false;
if (is_vma_temporary_stack(vma))
return false;
- return !(vma->vm_flags & VM_NO_THP);
+ return !(vma->vm_flags & VM_NO_KHUGEPAGED);
}
/*
diff --git a/mm/shmem.c b/mm/shmem.c
index c9d50d0802c8..a3d8469b18a7 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -101,6 +101,8 @@ struct shmem_falloc {
enum sgp_type {
SGP_READ, /* don't exceed i_size, don't allocate page */
SGP_CACHE, /* don't exceed i_size, may allocate page */
+ SGP_NOHUGE, /* like SGP_CACHE, but no huge pages */
+ SGP_HUGE, /* like SGP_CACHE, huge pages preferred */
SGP_WRITE, /* may exceed i_size, may allocate !Uptodate page */
SGP_FALLOC, /* like SGP_WRITE, but make existing page Uptodate */
};
@@ -1409,6 +1411,7 @@ static int shmem_getpage_gfp(struct inode *inode, pgoff_t index,
struct mem_cgroup *memcg;
struct page *page;
swp_entry_t swap;
+ enum sgp_type sgp_huge = sgp;
pgoff_t hindex = index;
int error;
int once = 0;
@@ -1416,6 +1419,8 @@ static int shmem_getpage_gfp(struct inode *inode, pgoff_t index,
if (index > (MAX_LFS_FILESIZE >> PAGE_SHIFT))
return -EFBIG;
+ if (sgp == SGP_NOHUGE || sgp == SGP_HUGE)
+ sgp = SGP_CACHE;
repeat:
swap.val = 0;
page = find_lock_entry(mapping, index);
@@ -1534,7 +1539,7 @@ repeat:
/* shmem_symlink() */
if (mapping->a_ops != &shmem_aops)
goto alloc_nohuge;
- if (shmem_huge == SHMEM_HUGE_DENY)
+ if (shmem_huge == SHMEM_HUGE_DENY || sgp_huge == SGP_NOHUGE)
goto alloc_nohuge;
if (shmem_huge == SHMEM_HUGE_FORCE)
goto alloc_huge;
@@ -1551,7 +1556,9 @@ repeat:
goto alloc_huge;
/* fallthrough */
case SHMEM_HUGE_ADVISE:
- /* TODO: wire up fadvise()/madvise() */
+ if (sgp_huge == SGP_HUGE)
+ goto alloc_huge;
+ /* TODO: implement fadvise() hints */
goto alloc_nohuge;
}
@@ -1680,6 +1687,7 @@ static int shmem_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
{
struct inode *inode = file_inode(vma->vm_file);
gfp_t gfp = mapping_gfp_mask(inode->i_mapping);
+ enum sgp_type sgp;
int error;
int ret = VM_FAULT_LOCKED;
@@ -1741,7 +1749,13 @@ static int shmem_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
spin_unlock(&inode->i_lock);
}
- error = shmem_getpage_gfp(inode, vmf->pgoff, &vmf->page, SGP_CACHE,
+ sgp = SGP_CACHE;
+ if (vma->vm_flags & VM_HUGEPAGE)
+ sgp = SGP_HUGE;
+ else if (vma->vm_flags & VM_NOHUGEPAGE)
+ sgp = SGP_NOHUGE;
+
+ error = shmem_getpage_gfp(inode, vmf->pgoff, &vmf->page, sgp,
gfp, vma->vm_mm, &ret);
if (error)
return ((error == -ENOMEM) ? VM_FAULT_OOM : VM_FAULT_SIGBUS);
--
2.8.1
next prev parent reply other threads:[~2016-06-07 11:01 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 ` [PATCHv9-rebased 15/32] thp, mlock: do not mlock PTE-mapped file huge pages Kirill A. Shutemov
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 ` Kirill A. Shutemov [this message]
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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