From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-12.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id DE712C5517A for ; Mon, 26 Oct 2020 04:41:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 99F1C20878 for ; Mon, 26 Oct 2020 04:41:39 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="YcfZjdNN" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1422266AbgJZElj (ORCPT ); Mon, 26 Oct 2020 00:41:39 -0400 Received: from casper.infradead.org ([90.155.50.34]:60076 "EHLO casper.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1421493AbgJZEli (ORCPT ); Mon, 26 Oct 2020 00:41:38 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=Content-Transfer-Encoding:MIME-Version: References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From:Sender:Reply-To: Content-Type:Content-ID:Content-Description; bh=kpUczdeKYi1+38xZwHEXixHpdmrDrWMrdTwGd2Ba8x0=; b=YcfZjdNN1aDe/LcHqu+I3/RUD7 ZB/2qcxmUEd0z/Z+O9YaxXNnWUummKleEY3HmDXPF9Z9OOL/EfnAFqBUH5T9hRUaOQTScouC78Aq3 xw8jSrszyqXqn+fwCOXxEUMcOyXHpzE8nFgzbwL/2K7eVO4HPakPOm+rnQy6p2csVx+4pPDsObLRm OZKyyMBUt4CJHQbpNVhyAGYa00xjzg9iaQ0UP/sx8iI2v8g0Ng5KC4SMhk37oLj49g8y97KRZo4Y9 keDM8o968FrKmDot2d98jRh6+ozGlQarsJz4VWaUjUssDqRLKqQCDReXLZw7XEU3VvvmQOfpsEwMJ prUEKttw==; Received: from willy by casper.infradead.org with local (Exim 4.92.3 #3 (Red Hat Linux)) id 1kWttd-0006as-1o; Mon, 26 Oct 2020 04:14:13 +0000 From: "Matthew Wilcox (Oracle)" To: linux-mm@kvack.org Cc: "Matthew Wilcox (Oracle)" , linux-fsdevel@vger.kernel.org, Andrew Morton , Hugh Dickins , Johannes Weiner , Yang Shi , Dave Chinner , linux-kernel@vger.kernel.org, Jan Kara , William Kucharski Subject: [PATCH v3 12/12] mm/filemap: Return only head pages from find_get_entries Date: Mon, 26 Oct 2020 04:14:08 +0000 Message-Id: <20201026041408.25230-13-willy@infradead.org> X-Mailer: git-send-email 2.21.3 In-Reply-To: <20201026041408.25230-1-willy@infradead.org> References: <20201026041408.25230-1-willy@infradead.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org All callers now expect head (and base) pages, and can handle multiple head pages in a single batch, so make find_get_entries() behave that way. Also take the opportunity to make it use the pagevec infrastructure instead of open-coding how pvecs behave. This has the side-effect of being able to append to a pagevec with existing contents, although we don't make use of that functionality anywhere yet. Signed-off-by: Matthew Wilcox (Oracle) Reviewed-by: Jan Kara Reviewed-by: William Kucharski --- include/linux/pagemap.h | 2 -- mm/filemap.c | 36 ++++++++---------------------------- mm/internal.h | 2 ++ 3 files changed, 10 insertions(+), 30 deletions(-) diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h index f0bbe29de732..8938c64f418b 100644 --- a/include/linux/pagemap.h +++ b/include/linux/pagemap.h @@ -449,8 +449,6 @@ static inline struct page *find_subpage(struct page *head, pgoff_t index) return head + (index & (thp_nr_pages(head) - 1)); } -unsigned find_get_entries(struct address_space *mapping, pgoff_t start, - pgoff_t end, struct pagevec *pvec, pgoff_t *indices); unsigned find_get_pages_range(struct address_space *mapping, pgoff_t *start, pgoff_t end, unsigned int nr_pages, struct page **pages); diff --git a/mm/filemap.c b/mm/filemap.c index e0fa943011d8..a117718ec1a8 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -1905,49 +1905,29 @@ static inline struct page *xas_find_get_entry(struct xa_state *xas, * the mapping. The entries are placed in @pvec. find_get_entries() * takes a reference on any actual pages it returns. * - * The search returns a group of mapping-contiguous page cache entries - * with ascending indexes. There may be holes in the indices due to - * not-present pages. + * The entries have ascending indexes. The indices may not be consecutive + * due to not-present entries or THPs. * * Any shadow entries of evicted pages, or swap entries from * shmem/tmpfs, are included in the returned array. * - * If it finds a Transparent Huge Page, head or tail, find_get_entries() - * stops at that page: the caller is likely to have a better way to handle - * the compound page as a whole, and then skip its extent, than repeatedly - * calling find_get_entries() to return all its tails. - * - * Return: the number of pages and shadow entries which were found. + * Return: The number of entries which were found. */ unsigned find_get_entries(struct address_space *mapping, pgoff_t start, pgoff_t end, struct pagevec *pvec, pgoff_t *indices) { XA_STATE(xas, &mapping->i_pages, start); struct page *page; - unsigned int ret = 0; - unsigned nr_entries = PAGEVEC_SIZE; rcu_read_lock(); while ((page = xas_find_get_entry(&xas, end, XA_PRESENT))) { - /* - * Terminate early on finding a THP, to allow the caller to - * handle it all at once; but continue if this is hugetlbfs. - */ - if (!xa_is_value(page) && PageTransHuge(page) && - !PageHuge(page)) { - page = find_subpage(page, xas.xa_index); - nr_entries = ret + 1; - } - - indices[ret] = xas.xa_index; - pvec->pages[ret] = page; - if (++ret == nr_entries) + indices[pvec->nr] = xas.xa_index; + if (!pagevec_add(pvec, page)) break; } rcu_read_unlock(); - pvec->nr = ret; - return ret; + return pagevec_count(pvec); } /** @@ -1966,8 +1946,8 @@ unsigned find_get_entries(struct address_space *mapping, pgoff_t start, * not returned. * * The entries have ascending indexes. The indices may not be consecutive - * due to not-present entries, THP pages, pages which could not be locked - * or pages under writeback. + * due to not-present entries, THPs, pages which could not be locked or + * pages under writeback. * * Return: The number of entries which were found. */ diff --git a/mm/internal.h b/mm/internal.h index 194572e1ab49..5aca7d7bc57c 100644 --- a/mm/internal.h +++ b/mm/internal.h @@ -62,6 +62,8 @@ static inline void force_page_cache_readahead(struct address_space *mapping, struct page *find_get_entry(struct address_space *mapping, pgoff_t index); struct page *find_lock_entry(struct address_space *mapping, pgoff_t index); +unsigned find_get_entries(struct address_space *mapping, pgoff_t start, + pgoff_t end, struct pagevec *pvec, pgoff_t *indices); unsigned find_lock_entries(struct address_space *mapping, pgoff_t start, pgoff_t end, struct pagevec *pvec, pgoff_t *indices); -- 2.28.0