From patchwork Thu May 3 19:24:28 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ross Zwisler X-Patchwork-Id: 10379005 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 1324760541 for ; Thu, 3 May 2018 19:24:38 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 07E7229259 for ; Thu, 3 May 2018 19:24:38 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id F09C229266; Thu, 3 May 2018 19:24:37 +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=-2.9 required=2.0 tests=BAYES_00, MAILING_LIST_MULTI, RCVD_IN_DNSWL_NONE autolearn=ham version=3.3.1 Received: from ml01.01.org (ml01.01.org [198.145.21.10]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id AA93D2925D for ; Thu, 3 May 2018 19:24:37 +0000 (UTC) Received: from [127.0.0.1] (localhost [IPv6:::1]) by ml01.01.org (Postfix) with ESMTP id A70B3203BEA56; Thu, 3 May 2018 12:24:36 -0700 (PDT) X-Original-To: linux-nvdimm@lists.01.org Delivered-To: linux-nvdimm@lists.01.org Received-SPF: None (no SPF record) identity=mailfrom; client-ip=192.55.52.43; helo=mga05.intel.com; envelope-from=ross.zwisler@linux.intel.com; receiver=linux-nvdimm@lists.01.org Received: from mga05.intel.com (mga05.intel.com [192.55.52.43]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ml01.01.org (Postfix) with ESMTPS id 796CC203BEA4C for ; Thu, 3 May 2018 12:24:35 -0700 (PDT) X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by fmsmga105.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 03 May 2018 12:24:35 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.49,359,1520924400"; d="scan'208";a="225573197" Received: from theros.lm.intel.com ([10.232.112.164]) by fmsmga005.fm.intel.com with ESMTP; 03 May 2018 12:24:34 -0700 From: Ross Zwisler To: Andrew Morton , linux-kernel@vger.kernel.org, Matthew Wilcox Subject: [PATCH 3/5] radix tree test suite: add item_delete_rcu() Date: Thu, 3 May 2018 13:24:28 -0600 Message-Id: <20180503192430.7582-4-ross.zwisler@linux.intel.com> X-Mailer: git-send-email 2.14.3 In-Reply-To: <20180503192430.7582-1-ross.zwisler@linux.intel.com> References: <20180503192430.7582-1-ross.zwisler@linux.intel.com> X-BeenThere: linux-nvdimm@lists.01.org X-Mailman-Version: 2.1.26 Precedence: list List-Id: "Linux-nvdimm developer list." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Jan Kara , linux-nvdimm@lists.01.org, Dave Chinner , Christoph Hellwig MIME-Version: 1.0 Errors-To: linux-nvdimm-bounces@lists.01.org Sender: "Linux-nvdimm" X-Virus-Scanned: ClamAV using ClamSMTP Currently the lifetime of "struct item" entries in the radix tree are not controlled by RCU, but are instead deleted inline as they are removed from the tree. In the following patches we add a test which has threads iterating over items pulled from the tree and verifying them in an rcu_read_lock()/rcu_read_unlock() section. This means that though an item has been removed from the tree it could still be being worked on by other threads until the RCU grace period expires. So, we need to actually free the "struct item" structures at the end of the grace period, just as we do with "struct radix_tree_node" items. Signed-off-by: Ross Zwisler --- tools/testing/radix-tree/test.c | 19 +++++++++++++++++++ tools/testing/radix-tree/test.h | 2 ++ 2 files changed, 21 insertions(+) diff --git a/tools/testing/radix-tree/test.c b/tools/testing/radix-tree/test.c index 5978ab1f403d..def6015570b2 100644 --- a/tools/testing/radix-tree/test.c +++ b/tools/testing/radix-tree/test.c @@ -75,6 +75,25 @@ int item_delete(struct radix_tree_root *root, unsigned long index) return 0; } +static void item_free_rcu(struct rcu_head *head) +{ + struct item *item = container_of(head, struct item, rcu_head); + + free(item); +} + +int item_delete_rcu(struct radix_tree_root *root, unsigned long index) +{ + struct item *item = radix_tree_delete(root, index); + + if (item) { + item_sanity(item, index); + call_rcu(&item->rcu_head, item_free_rcu); + return 1; + } + return 0; +} + void item_check_present(struct radix_tree_root *root, unsigned long index) { struct item *item; diff --git a/tools/testing/radix-tree/test.h b/tools/testing/radix-tree/test.h index d9c031dbeb1a..8cf4a7a7f94c 100644 --- a/tools/testing/radix-tree/test.h +++ b/tools/testing/radix-tree/test.h @@ -5,6 +5,7 @@ #include struct item { + struct rcu_head rcu_head; unsigned long index; unsigned int order; }; @@ -15,6 +16,7 @@ int item_insert(struct radix_tree_root *root, unsigned long index); int item_insert_order(struct radix_tree_root *root, unsigned long index, unsigned order); int item_delete(struct radix_tree_root *root, unsigned long index); +int item_delete_rcu(struct radix_tree_root *root, unsigned long index); struct item *item_lookup(struct radix_tree_root *root, unsigned long index); void item_check_present(struct radix_tree_root *root, unsigned long index);