For now we try to grab a huge cache page if the minimum requirements have been satisfied.
Signed-off-by: Ning Qu <[email protected]> --- mm/shmem.c | 31 ++++++++++++++++++++++++++----- 1 file changed, 26 insertions(+), 5 deletions(-) diff --git a/mm/shmem.c b/mm/shmem.c index 2fc450d..0a423a9 100644 --- a/mm/shmem.c +++ b/mm/shmem.c @@ -1640,8 +1640,21 @@ shmem_write_begin(struct file *file, struct address_space *mapping, struct inode *inode = mapping->host; pgoff_t index = pos >> PAGE_CACHE_SHIFT; gfp_t gfp = mapping_gfp_mask(inode->i_mapping); + int ret = 0; + int getpage_flags = 0; + +#ifdef CONFIG_TRANSPARENT_HUGEPAGE_PAGECACHE + /* + * Do not allocate a huge page in the first huge page range in page + * cache. This way we can avoid most small files overhead. + */ + if (pos >= HPAGE_PMD_SIZE) + getpage_flags |= AOP_FLAG_TRANSHUGE; +#endif + ret = shmem_getpage(inode, index, pagep, SGP_WRITE, gfp, + getpage_flags, NULL); - return shmem_getpage(inode, index, pagep, SGP_WRITE, gfp, 0, NULL); + return ret; } static int @@ -1655,10 +1668,18 @@ shmem_write_end(struct file *file, struct address_space *mapping, i_size_write(inode, pos + copied); if (!PageUptodate(page)) { - if (copied < PAGE_CACHE_SIZE) { - unsigned from = pos & (PAGE_CACHE_SIZE - 1); - zero_user_segments(page, 0, from, - from + copied, PAGE_CACHE_SIZE); + if (copied < len) { + unsigned from; + if (PageTransHugeCache(page)) { + from = pos & ~HPAGE_PMD_MASK; + zero_huge_user(page, 0, from); + zero_huge_user(page, from + copied, + HPAGE_PMD_SIZE); + } else { + from = pos & ~PAGE_CACHE_MASK; + zero_user_segments(page, 0, from, + from + copied, PAGE_CACHE_SIZE); + } } SetPageUptodate(page); } -- 1.8.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
