From: Gao Xiang Date: Thu, 22 Nov 2018 17:21:48 +0000 (+0800) Subject: staging: erofs: decompress asynchronously if PG_readahead page at first X-Git-Tag: v5.0-rc1~97^2~230 X-Git-Url: https://asedeno.scripts.mit.edu/gitweb/?a=commitdiff_plain;h=2d9b5dcd99428f9b8faea7f76c3e30c37c32cc9c;p=linux.git staging: erofs: decompress asynchronously if PG_readahead page at first For the case of nr_to_read == lookahead_size, it is better to decompress asynchronously as well since no page will be needed immediately. Reviewed-by: Chao Yu Signed-off-by: Gao Xiang Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/staging/erofs/unzip_vle.c b/drivers/staging/erofs/unzip_vle.c index 6aa3c989dd4e..fab907e0fe06 100644 --- a/drivers/staging/erofs/unzip_vle.c +++ b/drivers/staging/erofs/unzip_vle.c @@ -1345,8 +1345,8 @@ static int z_erofs_vle_normalaccess_readpages(struct file *filp, { struct inode *const inode = mapping->host; struct erofs_sb_info *const sbi = EROFS_I_SB(inode); - const bool sync = __should_decompress_synchronously(sbi, nr_pages); + bool sync = __should_decompress_synchronously(sbi, nr_pages); struct z_erofs_vle_frontend f = VLE_FRONTEND_INIT(inode); gfp_t gfp = mapping_gfp_constraint(mapping, GFP_KERNEL); struct page *head = NULL; @@ -1364,6 +1364,13 @@ static int z_erofs_vle_normalaccess_readpages(struct file *filp, prefetchw(&page->flags); list_del(&page->lru); + /* + * A pure asynchronous readahead is indicated if + * a PG_readahead marked page is hitted at first. + * Let's also do asynchronous decompression for this case. + */ + sync &= !(PageReadahead(page) && !head); + if (add_to_page_cache_lru(page, mapping, page->index, gfp)) { list_add(&page->lru, &pagepool); continue;