From patchwork Sat Jan 16 09:29:50 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sven Eckelmann X-Patchwork-Id: 5018 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=Wlb4Sstp; 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 87E7A81B7D for ; Sat, 16 Jan 2016 10:30:12 +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 5C142110114; Sat, 16 Jan 2016 10:30:10 +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=1452936610; bh=xxmEz04ij6r2f5bGaFSTCjK68LevErDT8Hucx8EAThQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Wlb4SstpJyUpKderSCoDbhLayLfwTDV05DDg+EyTCSdVLWQCmLUlehpTZgiXEptka aH66lgy0Gn3Dv9HNStAzcIiBwWbPpOUU7v1YVRWJqlcGSPPydhwde8HdMrodBMZWBC 2XqS7QgrYEFs8pCGWGG66dox+IhV7Xnpj6XpYPM0= From: Sven Eckelmann To: b.a.t.m.a.n@lists.open-mesh.org Date: Sat, 16 Jan 2016 10:29:50 +0100 Message-Id: <1452936598-28619-12-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 12/20] batman-adv: Convert batadv_tt_orig_list_entry 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 09:30:13 -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/translation-table.c | 26 +++++++++++++++++--------- net/batman-adv/types.h | 2 +- 2 files changed, 18 insertions(+), 10 deletions(-) diff --git a/net/batman-adv/translation-table.c b/net/batman-adv/translation-table.c index 0dc8a5c..68494a1 100644 --- a/net/batman-adv/translation-table.c +++ b/net/batman-adv/translation-table.c @@ -31,6 +31,7 @@ #include #include #include +#include #include #include #include @@ -346,22 +347,28 @@ static void batadv_tt_global_size_dec(struct batadv_orig_node *orig_node, /** * batadv_tt_orig_list_entry_release - release tt orig entry from lists and * queue for free after rcu grace period - * @orig_entry: tt orig entry to be free'd + * @ref: kref pointer of the tt orig entry */ -static void -batadv_tt_orig_list_entry_release(struct batadv_tt_orig_list_entry *orig_entry) +static void batadv_tt_orig_list_entry_release(struct kref *ref) { + struct batadv_tt_orig_list_entry *orig_entry; + + orig_entry = container_of(ref, struct batadv_tt_orig_list_entry, + refcount); + batadv_orig_node_free_ref(orig_entry->orig_node); kfree_rcu(orig_entry, rcu); } +/** + * batadv_tt_orig_list_entry_free_ref - decrement the tt orig entry refcounter + * and possibly release it + * @orig_entry: tt orig entry to be free'd + */ static void batadv_tt_orig_list_entry_free_ref(struct batadv_tt_orig_list_entry *orig_entry) { - if (!atomic_dec_and_test(&orig_entry->refcount)) - return; - - batadv_tt_orig_list_entry_release(orig_entry); + kref_put(&orig_entry->refcount, batadv_tt_orig_list_entry_release); } /** @@ -1270,7 +1277,7 @@ batadv_tt_global_orig_entry_find(const struct batadv_tt_global_entry *entry, hlist_for_each_entry_rcu(tmp_orig_entry, head, list) { if (tmp_orig_entry->orig_node != orig_node) continue; - if (!atomic_inc_not_zero(&tmp_orig_entry->refcount)) + if (!kref_get_unless_zero(&tmp_orig_entry->refcount)) continue; orig_entry = tmp_orig_entry; @@ -1331,7 +1338,8 @@ batadv_tt_global_orig_entry_add(struct batadv_tt_global_entry *tt_global, batadv_tt_global_size_inc(orig_node, tt_global->common.vid); orig_entry->orig_node = orig_node; orig_entry->ttvn = ttvn; - atomic_set(&orig_entry->refcount, 2); + kref_init(&orig_entry->refcount); + kref_get(&orig_entry->refcount); spin_lock_bh(&tt_global->list_lock); hlist_add_head_rcu(&orig_entry->list, diff --git a/net/batman-adv/types.h b/net/batman-adv/types.h index f89dd97..17f97ff 100644 --- a/net/batman-adv/types.h +++ b/net/batman-adv/types.h @@ -1014,7 +1014,7 @@ struct batadv_tt_orig_list_entry { struct batadv_orig_node *orig_node; u8 ttvn; struct hlist_node list; - atomic_t refcount; + struct kref refcount; struct rcu_head rcu; };