Messages in this thread Patch in this message | | | From | David Herrmann <> | Subject | [PATCH] mm/madvise: fix WILLNEED on SHM/ANON to actually do something | Date | Fri, 23 May 2014 14:12:15 +0200 |
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Currently, madvise(MADV_WILLNEED) on shmem with swap enabled is a no-op. Problem is, we use find_get_page() to lookup shmem pages in the given range. However, what we're actually interested in is swapped-out pages. Therefore, our current code is a no-op: page = find_get_page(mapping, index); if (!radix_tree_exceptional_entry(page)) bail-out;
find_get_page() never returns exceptional entries. Fix this by using find_get_entry(). This was probably meant to be used right from the beginning.
Signed-off-by: David Herrmann <dh.herrmann@gmail.com> --- mm/madvise.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/mm/madvise.c b/mm/madvise.c index 539eeb9..a402f8f 100644 --- a/mm/madvise.c +++ b/mm/madvise.c @@ -195,7 +195,7 @@ static void force_shm_swapin_readahead(struct vm_area_struct *vma, for (; start < end; start += PAGE_SIZE) { index = ((start - vma->vm_start) >> PAGE_SHIFT) + vma->vm_pgoff; - page = find_get_page(mapping, index); + page = find_get_entry(mapping, index); if (!radix_tree_exceptional_entry(page)) { if (page) page_cache_release(page); -- 1.9.3
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