From patchwork Mon Feb 19 19:45:30 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Matthew Wilcox X-Patchwork-Id: 10228691 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 6E96B602B1 for ; Mon, 19 Feb 2018 19:56:19 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 6086528B80 for ; Mon, 19 Feb 2018 19:56:19 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 55B4B28B83; Mon, 19 Feb 2018 19:56:19 +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 DA20D28B80 for ; Mon, 19 Feb 2018 19:56:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753934AbeBSTz0 (ORCPT ); Mon, 19 Feb 2018 14:55:26 -0500 Received: from bombadil.infradead.org ([198.137.202.133]:44838 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753733AbeBSTqU (ORCPT ); Mon, 19 Feb 2018 14:46:20 -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=a7OdpLGx9aHCqe+0ottu9IjOFjhDtgBlUqsQJV+xTG0=; b=PTI4/eLN8+Uvc5i/nCiOqh6Zs 3LOjudk29d/YvHNWFQGUuPXEx1UnYbdkqaPvFcjI1NYY0SaP2ecEmQVWJKg2zoSQ3LFqLBAXxryA7 ZRv7qnk5obAORccTgALpAqbKIg7dJgJe5phNJKC1T0d2fHHXexotVkSMOeVUbb6gKlRqWttpqEHV7 6dK98baBxkqxdjqULWiqUmrOwxywUUdGayLq21CSQej9l5hB8Lz0RU4ahL74zD1chVrfmk0tgQctv 1qYRZsnjOCIriqxBZHEtOoKnv8GiAvfF49Za0JNUmwcMhbz+K+XNz7jYiVFZt/ruNDb6tTgoyMI4s 23Xm3vFLA==; Received: from willy by bombadil.infradead.org with local (Exim 4.89 #1 (Red Hat Linux)) id 1enrOF-0001rV-2V; Mon, 19 Feb 2018 19:46:19 +0000 From: Matthew Wilcox To: Andrew Morton Cc: Matthew Wilcox , linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-fsdevel@vger.kernel.org Subject: [PATCH v7 35/61] mm: Convert truncate to XArray Date: Mon, 19 Feb 2018 11:45:30 -0800 Message-Id: <20180219194556.6575-36-willy@infradead.org> X-Mailer: git-send-email 2.14.3 In-Reply-To: <20180219194556.6575-1-willy@infradead.org> References: <20180219194556.6575-1-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 This is essentially xa_cmpxchg() with the locking handled above us, and it doesn't have to handle replacing a NULL entry. Signed-off-by: Matthew Wilcox --- mm/truncate.c | 15 ++++++--------- 1 file changed, 6 insertions(+), 9 deletions(-) diff --git a/mm/truncate.c b/mm/truncate.c index 3fe1e7461684..9267c1a12a31 100644 --- a/mm/truncate.c +++ b/mm/truncate.c @@ -33,15 +33,12 @@ static inline void __clear_shadow_entry(struct address_space *mapping, pgoff_t index, void *entry) { - struct radix_tree_node *node; - void **slot; + XA_STATE(xas, &mapping->pages, index); - if (!__radix_tree_lookup(&mapping->pages, index, &node, &slot)) + xas_set_update(&xas, workingset_update_node); + if (xas_load(&xas) != entry) return; - if (*slot != entry) - return; - __radix_tree_replace(&mapping->pages, node, slot, NULL, - workingset_update_node); + xas_store(&xas, NULL); mapping->nrexceptional--; } @@ -738,10 +735,10 @@ int invalidate_inode_pages2_range(struct address_space *mapping, index++; } /* - * For DAX we invalidate page tables after invalidating radix tree. We + * For DAX we invalidate page tables after invalidating page cache. We * could invalidate page tables while invalidating each entry however * that would be expensive. And doing range unmapping before doesn't - * work as we have no cheap way to find whether radix tree entry didn't + * work as we have no cheap way to find whether page cache entry didn't * get remapped later. */ if (dax_mapping(mapping)) {