From patchwork Sat Jan 16 09:29:45 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sven Eckelmann X-Patchwork-Id: 4999 Return-Path: Received-SPF: Pass (sender SPF authorized) identity=mailfrom; client-ip=79.140.41.39; helo=v3-1039.vlinux.de; envelope-from=sven@narfation.org; receiver=b.a.t.m.a.n@lists.open-mesh.org Authentication-Results: open-mesh.org; dmarc=pass header.from=narfation.org Authentication-Results: open-mesh.org; dkim=pass reason="1024-bit key; unprotected key" header.d=narfation.org header.i=@narfation.org header.b=aKX4CjhK; dkim-adsp=pass; dkim-atps=neutral Received: from v3-1039.vlinux.de (narfation.org [79.140.41.39]) by open-mesh.org (Postfix) with ESMTPS id 3CDE981B76 for ; Sat, 16 Jan 2016 10:30:07 +0100 (CET) Received: from sven-desktop.home.narfation.org (p200300C593C167FD0000000000002E16.dip0.t-ipconnect.de [IPv6:2003:c5:93c1:67fd::2e16]) by v3-1039.vlinux.de (Postfix) with ESMTPSA id B213A1100E7; Sat, 16 Jan 2016 10:30:06 +0100 (CET) Authentication-Results: v3-1039.vlinux.de; dmarc=none header.from=narfation.org DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=narfation.org; s=20121; t=1452936606; bh=wlTQksXFcRVK1bkUW2yQCIxNX2bKHkMqSEG0O9hbOP8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=aKX4CjhKqk2K/CGapRz6JgxMzmUxK67Cg2sNQJ80UwgCuCJ0ELYAHmMjW5228m7zE 9HdUloPV9jevn+BNJzkqQvF5it0rMPdr1VDy5kfaq3BrIMIO+mnS17ErMXnhb7+qtU m005kCR2Wvd5FTztzUebgHZfKE6UKYTgjp5o4tjY= From: Sven Eckelmann To: b.a.t.m.a.n@lists.open-mesh.org Date: Sat, 16 Jan 2016 10:29:45 +0100 Message-Id: <1452936598-28619-7-git-send-email-sven@narfation.org> X-Mailer: git-send-email 2.7.0.rc3 In-Reply-To: <1452936598-28619-1-git-send-email-sven@narfation.org> References: <1452936598-28619-1-git-send-email-sven@narfation.org> Subject: [B.A.T.M.A.N.] [PATCH v6 07/20] batman-adv: Convert batadv_nc_node to kref X-BeenThere: b.a.t.m.a.n@lists.open-mesh.org X-Mailman-Version: 2.1.18 Precedence: list List-Id: The list for a Better Approach To Mobile Ad-hoc Networking List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 16 Jan 2016 09:30:07 -0000 batman-adv uses a self-written reference implementation which is just based on atomic_t. This is less obvious when reading the code than kref and therefore increases the change that the reference counting will be missed. Signed-off-by: Sven Eckelmann --- v6: - removed patches which are now applied in the branch next - rebased remaining patches on the patch "batman-adv: Avoid recursive call_rcu for batadv_nc_node" which was modified by Marek while he applied the patches (this unfortunately made some of the remaining patches "hard" to apply) v5: - add hack which allows to compile against stable kernel like 3.2.44 which also added the kref_get_unless_zero function v4: - fix function names in commit messages - fix double whitespace in batadv_tt_orig_list_entry_release kerneldoc - add extra patch for batadv_claim_free_ref kerneldoc fix - change the phrase "free it" in all *_free_ref/*_put functions to "release it" v3: - update copyright year v2: - split patchset into fixes and kref migration to make it easier when the decision is made where each patch will be applied net/batman-adv/network-coding.c | 21 +++++++++++++-------- net/batman-adv/types.h | 2 +- 2 files changed, 14 insertions(+), 9 deletions(-) diff --git a/net/batman-adv/network-coding.c b/net/batman-adv/network-coding.c index 0b30c15..7a1216e 100644 --- a/net/batman-adv/network-coding.c +++ b/net/batman-adv/network-coding.c @@ -32,6 +32,7 @@ #include #include #include +#include #include #include #include @@ -209,23 +210,26 @@ void batadv_nc_init_orig(struct batadv_orig_node *orig_node) /** * batadv_nc_node_release - release nc_node from lists and queue for free after * rcu grace period - * @nc_node: the nc node to free + * @ref: kref pointer of the nc_node */ -static void batadv_nc_node_release(struct batadv_nc_node *nc_node) +static void batadv_nc_node_release(struct kref *ref) { + struct batadv_nc_node *nc_node; + + nc_node = container_of(ref, struct batadv_nc_node, refcount); + batadv_orig_node_free_ref(nc_node->orig_node); kfree_rcu(nc_node, rcu); } /** - * batadv_nc_node_free_ref - decrement the nc node refcounter and possibly + * batadv_nc_node_free_ref - decrement the nc_node refcounter and possibly * release it - * @nc_node: the nc node to free + * @nc_node: nc_node to be free'd */ static void batadv_nc_node_free_ref(struct batadv_nc_node *nc_node) { - if (atomic_dec_and_test(&nc_node->refcount)) - batadv_nc_node_release(nc_node); + kref_put(&nc_node->refcount, batadv_nc_node_release); } /** @@ -797,7 +801,7 @@ static struct batadv_nc_node if (!batadv_compare_eth(nc_node->addr, orig_node->orig)) continue; - if (!atomic_inc_not_zero(&nc_node->refcount)) + if (!kref_get_unless_zero(&nc_node->refcount)) continue; /* Found a match */ @@ -848,7 +852,8 @@ static struct batadv_nc_node INIT_LIST_HEAD(&nc_node->list); ether_addr_copy(nc_node->addr, orig_node->orig); nc_node->orig_node = orig_neigh_node; - atomic_set(&nc_node->refcount, 2); + kref_init(&nc_node->refcount); + kref_get(&nc_node->refcount); /* Select ingoing or outgoing coding node */ if (in_coding) { diff --git a/net/batman-adv/types.h b/net/batman-adv/types.h index 34c13b6..05421af 100644 --- a/net/batman-adv/types.h +++ b/net/batman-adv/types.h @@ -1067,7 +1067,7 @@ struct batadv_tt_roam_node { struct batadv_nc_node { struct list_head list; u8 addr[ETH_ALEN]; - atomic_t refcount; + struct kref refcount; struct rcu_head rcu; struct batadv_orig_node *orig_node; unsigned long last_seen;