From patchwork Wed Dec 6 00:41:34 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Matthew Wilcox X-Patchwork-Id: 10094421 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 40DC260329 for ; Wed, 6 Dec 2017 00:52:29 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 31DD728D2F for ; Wed, 6 Dec 2017 00:52:29 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 1F78D28A46; Wed, 6 Dec 2017 00:52:29 +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=ham 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 7620B291A1 for ; Wed, 6 Dec 2017 00:52:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753891AbdLFAva (ORCPT ); Tue, 5 Dec 2017 19:51:30 -0500 Received: from bombadil.infradead.org ([65.50.211.133]:37428 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753361AbdLFAmO (ORCPT ); Tue, 5 Dec 2017 19:42:14 -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=f6bcDsvF4QZUZv6JZNNkEzlvmKtPlhOYVamkIxrG9hI=; b=BWN8ETiD5C7ndsrQkBJPZeS7N oPibbwAG/nwXoiT6G00bV8TJMhMPjVxr0L3NkIuTC9hZAv0Fh+YplWR7ygHigHpD4+6BZA4u5vtpM AmDp/PqpHv336CHgp11XQy9pWl2BTGMqZRynt/iEwpZ1WaR9hfTlCnbkB+dsX5P7t3BYcNoJUFuQf Keoj6/mPpV98cdpFOTSxx5t2I3kVqI52M8lnv9Yrg0e1zq4Ul/YorQxD8I+avlf+HFaxU4t47Wlf9 HcUmvQ/CynFsrzQ6gpMpzYbmnAsMHz1iRLgxGAXNlFpOonN70MIuql6b9JArwGNfSOJYj1lHJ/AIu Z7bX8k0Tg==; Received: from willy by bombadil.infradead.org with local (Exim 4.87 #1 (Red Hat Linux)) id 1eMNmt-00018S-9v; Wed, 06 Dec 2017 00:42:11 +0000 From: Matthew Wilcox Cc: Matthew Wilcox , Ross Zwisler , Jens Axboe , Rehas Sachdeva , linux-mm@kvack.org, linux-fsdevel@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net, linux-nilfs@vger.kernel.org, linux-btrfs@vger.kernel.org, linux-xfs@vger.kernel.org, linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v4 48/73] shmem: Convert shmem_free_swap to XArray Date: Tue, 5 Dec 2017 16:41:34 -0800 Message-Id: <20171206004159.3755-49-willy@infradead.org> X-Mailer: git-send-email 2.9.5 In-Reply-To: <20171206004159.3755-1-willy@infradead.org> References: <20171206004159.3755-1-willy@infradead.org> To: unlisted-recipients:; (no To-header on input) Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Matthew Wilcox This is a perfect use for xa_cmpxchg(). Note the use of 0 for GFP flags; we won't be allocating memory. Signed-off-by: Matthew Wilcox --- mm/shmem.c | 7 ++----- 1 file changed, 2 insertions(+), 5 deletions(-) diff --git a/mm/shmem.c b/mm/shmem.c index 768d470a03da..ca45ff493587 100644 --- a/mm/shmem.c +++ b/mm/shmem.c @@ -635,16 +635,13 @@ static void shmem_delete_from_page_cache(struct page *page, void *radswap) } /* - * Remove swap entry from radix tree, free the swap and its page cache. + * Remove swap entry from page cache, free the swap and its page cache. */ static int shmem_free_swap(struct address_space *mapping, pgoff_t index, void *radswap) { - void *old; + void *old = xa_cmpxchg(&mapping->pages, index, radswap, NULL, 0); - xa_lock_irq(&mapping->pages); - old = radix_tree_delete_item(&mapping->pages, index, radswap); - xa_unlock_irq(&mapping->pages); if (old != radswap) return -ENOENT; free_swap_and_cache(radix_to_swp_entry(radswap));