From patchwork Fri Dec 15 22:04:21 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Matthew Wilcox (Oracle)" X-Patchwork-Id: 10116519 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 2C90660327 for ; Fri, 15 Dec 2017 22:31:36 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 1F14C292A6 for ; Fri, 15 Dec 2017 22:31:36 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 137CB292AC; Fri, 15 Dec 2017 22:31:36 +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 B47F2292A6 for ; Fri, 15 Dec 2017 22:31:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757078AbdLOW3h (ORCPT ); Fri, 15 Dec 2017 17:29:37 -0500 Received: from bombadil.infradead.org ([65.50.211.133]:53578 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756394AbdLOWFW (ORCPT ); Fri, 15 Dec 2017 17:05:22 -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=xBhPUIl9cv3Z/oFe2KVJVIer6tyvBPl3fPwZBjuWuVE=; b=FQTMu7gahXwoPMGHenIWnKIK/ 3AzjPYPFu3bhUolwu17CPnr2NrBNrZyA2SJcYdWFcIBTnAWDr7UpZ/Ee7xl2MA+PL8yL5ss5YJwhf EqpJhROOw5TtIc1SHoADcJJJXUPJclMfTuExZcuaFGlKTvSf7mzyp6z++L8Icl7KS5s8o0AK0KnH8 XLO87AAGf8OvBRa1mqU1Apx3rnIMelXz+qC49P8DVuNoQirXduzR+VdsIq/6zibzc/TrnJWjpmH3L 6TKGmM+57O3sXB+xrc2kp1LEIQaXvFmGbx2th4YArVpEy7DCpjOjeBKyINIQNuJN+r/1C3u0Rp+1l PTZQTmTFA==; Received: from willy by bombadil.infradead.org with local (Exim 4.87 #1 (Red Hat Linux)) id 1ePy6I-00028w-4Q; Fri, 15 Dec 2017 22:05:02 +0000 From: Matthew Wilcox To: linux-kernel@vger.kernel.org Cc: Matthew Wilcox , Ross Zwisler , David Howells , Shaohua Li , Jens Axboe , Rehas Sachdeva , Marc Zyngier , 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-raid@vger.kernel.org Subject: [PATCH v5 49/78] shmem: Convert shmem_free_swap to XArray Date: Fri, 15 Dec 2017 14:04:21 -0800 Message-Id: <20171215220450.7899-50-willy@infradead.org> X-Mailer: git-send-email 2.9.5 In-Reply-To: <20171215220450.7899-1-willy@infradead.org> References: <20171215220450.7899-1-willy@infradead.org> 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 bd66bbd40499..dd663341e01e 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));