From patchwork Sat Jan 16 09:29:44 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sven Eckelmann X-Patchwork-Id: 5009 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=vtiMHWBx; 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 5D19B81B74 for ; Sat, 16 Jan 2016 10:30:06 +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 E77901100E7; Sat, 16 Jan 2016 10:30:05 +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=k92hMqsXiMlkAMEAby08ncXz/Q+AhZoD/j/xb9s2m6Y=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=vtiMHWBx1N7rWdEsPYswdTb1frh1RPB0Gp5w2wV8FlsM4FKsYfjt+0K7zkW5XjGpI xlyO8u/i2RvmroCX3kFbqBl0AXqMjiplcnrzA5QaqqK65jVrOGQ8mTd8Wkj8al73RP zgPH6fDV1fIc3aerFNzKB/lJUYViMXRdSend9tlI= From: Sven Eckelmann To: b.a.t.m.a.n@lists.open-mesh.org Date: Sat, 16 Jan 2016 10:29:44 +0100 Message-Id: <1452936598-28619-6-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 06/20] batman-adv: Convert batadv_bla_claim 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 09:30:06 -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/bridge_loop_avoidance.c | 16 ++++++++++------ net/batman-adv/types.h | 2 +- 2 files changed, 11 insertions(+), 7 deletions(-) diff --git a/net/batman-adv/bridge_loop_avoidance.c b/net/batman-adv/bridge_loop_avoidance.c index 0937097..7781f39 100644 --- a/net/batman-adv/bridge_loop_avoidance.c +++ b/net/batman-adv/bridge_loop_avoidance.c @@ -172,10 +172,14 @@ batadv_backbone_gw_free_ref(struct batadv_bla_backbone_gw *backbone_gw) /** * batadv_claim_release - release claim from lists and queue for free after rcu * grace period - * @claim: claim to be free'd + * @ref: kref pointer of the claim */ -static void batadv_claim_release(struct batadv_bla_claim *claim) +static void batadv_claim_release(struct kref *ref) { + struct batadv_bla_claim *claim; + + claim = container_of(ref, struct batadv_bla_claim, refcount); + batadv_backbone_gw_free_ref(claim->backbone_gw); kfree_rcu(claim, rcu); } @@ -187,8 +191,7 @@ static void batadv_claim_release(struct batadv_bla_claim *claim) */ static void batadv_claim_free_ref(struct batadv_bla_claim *claim) { - if (atomic_dec_and_test(&claim->refcount)) - batadv_claim_release(claim); + kref_put(&claim->refcount, batadv_claim_release); } /** @@ -219,7 +222,7 @@ static struct batadv_bla_claim if (!batadv_compare_claim(&claim->hash_entry, data)) continue; - if (!atomic_inc_not_zero(&claim->refcount)) + if (!kref_get_unless_zero(&claim->refcount)) continue; claim_tmp = claim; @@ -651,7 +654,8 @@ static void batadv_bla_add_claim(struct batadv_priv *bat_priv, claim->lasttime = jiffies; claim->backbone_gw = backbone_gw; - atomic_set(&claim->refcount, 2); + kref_init(&claim->refcount); + kref_get(&claim->refcount); batadv_dbg(BATADV_DBG_BLA, bat_priv, "bla_add_claim(): adding new entry %pM, vid %d to hash ...\n", mac, BATADV_PRINT_VID(vid)); diff --git a/net/batman-adv/types.h b/net/batman-adv/types.h index 595f524..34c13b6 100644 --- a/net/batman-adv/types.h +++ b/net/batman-adv/types.h @@ -951,7 +951,7 @@ struct batadv_bla_claim { unsigned long lasttime; struct hlist_node hash_entry; struct rcu_head rcu; - atomic_t refcount; + struct kref refcount; }; #endif