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| author | Kirill A. Shutemov <kirill.shutemov@linux.intel.com> | 2016-07-27 00:26:21 +0200 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2016-07-27 01:19:19 +0200 |
| commit | 657e3038c4e6fcd3cef41f2b01c655a685a7b8c7 (patch) | |
| tree | ad015c70c6a1befac182b9113ac4d27cf94dadb7 /mm/shmem.c | |
| parent | shmem: add huge pages support (diff) | |
| download | linux-657e3038c4e6fcd3cef41f2b01c655a685a7b8c7.tar.xz linux-657e3038c4e6fcd3cef41f2b01c655a685a7b8c7.zip | |
shmem, thp: respect MADV_{NO,}HUGEPAGE for file mappings
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.
Link: http://lkml.kernel.org/r/1466021202-61880-31-git-send-email-kirill.shutemov@linux.intel.com
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to '')
| -rw-r--r-- | mm/shmem.c | 20 |
1 files changed, 17 insertions, 3 deletions
diff --git a/mm/shmem.c b/mm/shmem.c index 302ae4a0af3d..f19b6b44ae46 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); |