diff options
| author | Rik van Riel <riel@surriel.com> | 2021-02-26 04:16:25 +0300 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2021-02-26 20:40:59 +0300 |
| commit | cd89fb06509903f942a0ffe97ffa63034671ed0c (patch) | |
| tree | a5c530688dfd1109937e3019bd038577dcbeda6b /mm/khugepaged.c | |
| parent | 78cc8cdc54008f54b79711fc027afc3564588a04 (diff) | |
| download | linux-cd89fb06509903f942a0ffe97ffa63034671ed0c.tar.xz | |
mm,thp,shmem: make khugepaged obey tmpfs mount flags
Currently if thp enabled=[madvise], mounting a tmpfs filesystem with
huge=always and mmapping files from that tmpfs does not result in
khugepaged collapsing those mappings, despite the mount flag indicating
that it should.
Fix that by breaking up the blocks of tests in hugepage_vma_check a little
bit, and testing things in the correct order.
Link: https://lkml.kernel.org/r/20201124194925.623931-4-riel@surriel.com
Fixes: c2231020ea7b ("mm: thp: register mm for khugepaged when merging vma for shmem")
Signed-off-by: Rik van Riel <riel@surriel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Xu Yu <xuyu@linux.alibaba.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm/khugepaged.c')
| -rw-r--r-- | mm/khugepaged.c | 22 |
1 files changed, 16 insertions, 6 deletions
diff --git a/mm/khugepaged.c b/mm/khugepaged.c index 75e246f680f4..a7d6cb912b05 100644 --- a/mm/khugepaged.c +++ b/mm/khugepaged.c @@ -442,18 +442,28 @@ static inline int khugepaged_test_exit(struct mm_struct *mm) static bool hugepage_vma_check(struct vm_area_struct *vma, unsigned long vm_flags) { - if ((!(vm_flags & VM_HUGEPAGE) && !khugepaged_always()) || - (vm_flags & VM_NOHUGEPAGE) || + /* Explicitly disabled through madvise. */ + if ((vm_flags & VM_NOHUGEPAGE) || test_bit(MMF_DISABLE_THP, &vma->vm_mm->flags)) return false; - if (shmem_file(vma->vm_file) || - (IS_ENABLED(CONFIG_READ_ONLY_THP_FOR_FS) && - vma->vm_file && - (vm_flags & VM_DENYWRITE))) { + /* Enabled via shmem mount options or sysfs settings. */ + if (shmem_file(vma->vm_file) && shmem_huge_enabled(vma)) { return IS_ALIGNED((vma->vm_start >> PAGE_SHIFT) - vma->vm_pgoff, HPAGE_PMD_NR); } + + /* THP settings require madvise. */ + if (!(vm_flags & VM_HUGEPAGE) && !khugepaged_always()) + return false; + + /* Read-only file mappings need to be aligned for THP to work. */ + if (IS_ENABLED(CONFIG_READ_ONLY_THP_FOR_FS) && vma->vm_file && + (vm_flags & VM_DENYWRITE)) { + return IS_ALIGNED((vma->vm_start >> PAGE_SHIFT) - vma->vm_pgoff, + HPAGE_PMD_NR); + } + if (!vma->anon_vma || vma->vm_ops) return false; if (vma_is_temporary_stack(vma)) |