Re: [PATCH 03/12] readahead: Put pages in cache earlier

From: Matthew Wilcox
Date: Sat Jan 25 2020 - 14:44:52 EST


On Fri, Jan 24, 2020 at 05:35:44PM -0800, Matthew Wilcox wrote:
> @@ -192,8 +194,18 @@ unsigned long __do_page_cache_readahead(struct address_space *mapping,
> page = __page_cache_alloc(gfp_mask);
> if (!page)
> break;
> - page->index = page_offset;
> - list_add(&page->lru, &page_pool);
> + if (use_list) {
> + page->index = page_offset;
> + list_add(&page->lru, &page_pool);
> + } else if (!add_to_page_cache_lru(page, mapping, page_offset,
> + gfp_mask)) {
> + if (nr_pages)
> + read_pages(mapping, filp, &page_pool,
> + page_offset - nr_pages,
> + nr_pages);
> + nr_pages = 0;

This is missing a call to put_page().

> + continue;
> + }
> if (page_idx == nr_to_read - lookahead_size)
> SetPageReadahead(page);
> nr_pages++;