From patchwork Tue Mar 6 19:23:43 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Matthew Wilcox X-Patchwork-Id: 10262697 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id DDB21602C8 for ; Tue, 6 Mar 2018 19:38:33 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id CC77A29147 for ; Tue, 6 Mar 2018 19:38:33 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id C16D92915E; Tue, 6 Mar 2018 19:38:33 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.8 required=2.0 tests=BAYES_00,DKIM_SIGNED, RCVD_IN_DNSWL_HI,T_DKIM_INVALID autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 7857229147 for ; Tue, 6 Mar 2018 19:38:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753045AbeCFThg (ORCPT ); Tue, 6 Mar 2018 14:37:36 -0500 Received: from bombadil.infradead.org ([198.137.202.133]:49036 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933183AbeCFTYb (ORCPT ); Tue, 6 Mar 2018 14:24:31 -0500 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=References:In-Reply-To:Message-Id: Date:Subject:Cc:To:From:Sender:Reply-To:MIME-Version:Content-Type: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=TUtEh0M91EPdkADjFqpMeEIRJ3g2LkGH+aLO+Cd7bW8=; b=q4H+4vRQi1lbysigXYE+Xt0WB Te3Qm8zoRmMIUOuDE3uxVK0LLTKOGKoEEpikavsoLvsUWRNRKQEAidAtRUu5Fn0pJAPK86yPgZ5F0 Cnfd/2JubV1FO0wsAF+1b78i9zQADlKys7pjrq0ewLAesRvaXNqRBNMedmvM+B4va7wyOTSgKogXg dfpbQAETi0ASmOJ7TC7npk+kaahuvBq+MUNHZcgAiLa2YWnZ0jf2hsQkouazlS+jPb7QjZR3MpnwF 6NuxoLIN89VS3I+WPU9PYTyDEN7Mb+sXnTg3OEg1hSvPnSJ8DYXvFhamPJDvo2CGD5wpq4pevhv0t Dw6qRA97Q==; Received: from willy by bombadil.infradead.org with local (Exim 4.89 #1 (Red Hat Linux)) id 1etICM-0001YE-JF; Tue, 06 Mar 2018 19:24:30 +0000 From: Matthew Wilcox To: Andrew Morton Cc: Matthew Wilcox , linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-fsdevel@vger.kernel.org, Ryusuke Konishi , linux-nilfs@vger.kernel.org, linux-btrfs@vger.kernel.org Subject: [PATCH v8 33/63] page cache: Convert filemap_range_has_page to XArray Date: Tue, 6 Mar 2018 11:23:43 -0800 Message-Id: <20180306192413.5499-34-willy@infradead.org> X-Mailer: git-send-email 2.14.3 In-Reply-To: <20180306192413.5499-1-willy@infradead.org> References: <20180306192413.5499-1-willy@infradead.org> Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Matthew Wilcox Instead of calling find_get_pages_range() and putting any reference, use xas_find() to iterate over any entries in the range, skipping the shadow/swap entries. Signed-off-by: Matthew Wilcox --- mm/filemap.c | 26 ++++++++++++++++++-------- 1 file changed, 18 insertions(+), 8 deletions(-) diff --git a/mm/filemap.c b/mm/filemap.c index 86c83014c909..9bc417913269 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -458,20 +458,30 @@ EXPORT_SYMBOL(filemap_flush); bool filemap_range_has_page(struct address_space *mapping, loff_t start_byte, loff_t end_byte) { - pgoff_t index = start_byte >> PAGE_SHIFT; - pgoff_t end = end_byte >> PAGE_SHIFT; struct page *page; + XA_STATE(xas, &mapping->i_pages, start_byte >> PAGE_SHIFT); + pgoff_t max = end_byte >> PAGE_SHIFT; if (end_byte < start_byte) return false; - if (mapping->nrpages == 0) - return false; + rcu_read_lock(); + do { + page = xas_find(&xas, max); + if (xas_retry(&xas, page)) + continue; + /* Shadow entries don't count */ + if (xa_is_value(page)) + continue; + /* + * We don't need to try to pin this page; we're about to + * release the RCU lock anyway. It is enough to know that + * there was a page here recently. + */ + } while (0); + rcu_read_unlock(); - if (!find_get_pages_range(mapping, &index, end, 1, &page)) - return false; - put_page(page); - return true; + return page != NULL; } EXPORT_SYMBOL(filemap_range_has_page);