From patchwork Mon Feb 19 19:45:46 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Matthew Wilcox X-Patchwork-Id: 10228581 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 89481602B1 for ; Mon, 19 Feb 2018 19:48:03 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 7B4A828792 for ; Mon, 19 Feb 2018 19:48:03 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 6FD9D287AB; Mon, 19 Feb 2018 19:48:03 +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 0A0A728792 for ; Mon, 19 Feb 2018 19:48:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932084AbeBSTqf (ORCPT ); Mon, 19 Feb 2018 14:46:35 -0500 Received: from bombadil.infradead.org ([198.137.202.133]:45022 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753817AbeBSTq3 (ORCPT ); Mon, 19 Feb 2018 14:46:29 -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=m9hW1qE0SaGYKZaZpg8nqlTwemLV/uq7rzLBK8r5wYw=; b=jGxx7SSdes/38iePHGZsrET7c ZzTMMHDmoSm4vcS3AauiAAFF4VcYPowcOy2LvsZxBwk01cYzxpIPoYyi1hHqipQh3hJihhY4eTOL2 zycL4ub9fFi1RXs1b3MAaNh7kL7ioAihgEpDJAP28dFlOw4FLWsB2FqvIlTTJgv8p+m04hBs7oXJj Zud+ibwKJyUt7vmB0demSi6NK0D7ydc2JVOSB3oUPAf5aBNnzJdl/XR47vVHsZKTmYAeL8RZvVgtr l0alspkPI6nxX/4r96DyciADVqH2DgxLUuPQYseaxXXqDY6WkzpDiSA3CPyv0k/Z6h9Dt7SKFMAkD pzuVaEzjg==; Received: from willy by bombadil.infradead.org with local (Exim 4.89 #1 (Red Hat Linux)) id 1enrON-0001va-Gg; Mon, 19 Feb 2018 19:46:27 +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 51/61] shmem: Convert shmem_free_swap to XArray Date: Mon, 19 Feb 2018 11:45:46 -0800 Message-Id: <20180219194556.6575-52-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 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 50f068f59c82..a7931660897d 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));