From patchwork Fri May 18 01:47:48 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Marek Lindner X-Patchwork-Id: 17366 X-Patchwork-Delegate: sw@simonwunderlich.de Return-Path: X-Original-To: patchwork@open-mesh.org Delivered-To: patchwork@open-mesh.org Received: from open-mesh.org (localhost [IPv6:::1]) by open-mesh.org (Postfix) with ESMTP id 48D4882522; Fri, 18 May 2018 03:48:22 +0200 (CEST) Received-SPF: Pass (mailfrom) identity=mailfrom; client-ip=5.148.176.60; helo=s2.neomailbox.net; envelope-from=mareklindner@neomailbox.ch; receiver= Received: from s2.neomailbox.net (s2.neomailbox.net [5.148.176.60]) by open-mesh.org (Postfix) with ESMTPS id B4C2F82519 for ; Fri, 18 May 2018 03:48:18 +0200 (CEST) From: Marek Lindner To: b.a.t.m.a.n@lists.open-mesh.org Date: Fri, 18 May 2018 09:47:48 +0800 Message-Id: <20180518014754.23644-2-mareklindner@neomailbox.ch> In-Reply-To: <20180518014754.23644-1-mareklindner@neomailbox.ch> References: <20180518014754.23644-1-mareklindner@neomailbox.ch> Subject: [B.A.T.M.A.N.] [PATCH v2 1/7] batman-adv: tp_meter - prevent concurrent tp_meter sessions by using workqueue X-BeenThere: b.a.t.m.a.n@lists.open-mesh.org X-Mailman-Version: 2.1.23 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: , Reply-To: The list for a Better Approach To Mobile Ad-hoc Networking Cc: Antonio Quartulli Errors-To: b.a.t.m.a.n-bounces@lists.open-mesh.org Sender: "B.A.T.M.A.N" From: Antonio Quartulli To ensure that no more than one tp_meter session runs at the same time, use an ordered workqueue instead of spawning one kthread per session. Signed-off-by: Antonio Quartulli --- net/batman-adv/main.c | 10 ++++- net/batman-adv/tp_meter.c | 77 +++++++++++++++++++-------------------- net/batman-adv/tp_meter.h | 3 +- net/batman-adv/types.h | 3 ++ 4 files changed, 50 insertions(+), 43 deletions(-) diff --git a/net/batman-adv/main.c b/net/batman-adv/main.c index 69c0d85b..cd3f1924 100644 --- a/net/batman-adv/main.c +++ b/net/batman-adv/main.c @@ -91,6 +91,10 @@ static int __init batadv_init(void) if (ret < 0) return ret; + ret = batadv_tp_meter_init(); + if (ret < 0) + goto err_tp_meter; + INIT_LIST_HEAD(&batadv_hardif_list); batadv_algo_init(); @@ -99,7 +103,6 @@ static int __init batadv_init(void) batadv_v_init(); batadv_iv_init(); batadv_nc_init(); - batadv_tp_meter_init(); batadv_event_workqueue = create_singlethread_workqueue("bat_events"); if (!batadv_event_workqueue) @@ -118,9 +121,11 @@ static int __init batadv_init(void) return 0; err_create_wq: + batadv_tp_meter_destroy(); +err_tp_meter: batadv_tt_cache_destroy(); - return -ENOMEM; + return ret; } static void __exit batadv_exit(void) @@ -138,6 +143,7 @@ static void __exit batadv_exit(void) rcu_barrier(); batadv_tt_cache_destroy(); + batadv_tp_meter_destroy(); } /** diff --git a/net/batman-adv/tp_meter.c b/net/batman-adv/tp_meter.c index 11520de9..c0d27f7d 100644 --- a/net/batman-adv/tp_meter.c +++ b/net/batman-adv/tp_meter.c @@ -32,7 +32,6 @@ #include #include #include -#include #include #include #include @@ -97,6 +96,9 @@ static u8 batadv_tp_prerandom[4096] __read_mostly; +/* ordered work queue */ +static struct workqueue_struct *batadv_tp_meter_queue; + /** * batadv_tp_session_cookie() - generate session cookie based on session ids * @session: TP session identifier @@ -808,19 +810,22 @@ static int batadv_tp_wait_available(struct batadv_tp_vars *tp_vars, size_t plen) /** * batadv_tp_send() - main sending thread of a tp meter session - * @arg: address of the related tp_vars + * @work: delayed work reference of the related tp_vars * * Return: nothing, this function never returns */ -static int batadv_tp_send(void *arg) +static void batadv_tp_send(struct work_struct *work) { - struct batadv_tp_vars *tp_vars = arg; - struct batadv_priv *bat_priv = tp_vars->bat_priv; struct batadv_hard_iface *primary_if = NULL; struct batadv_orig_node *orig_node = NULL; + struct batadv_tp_vars *tp_vars; size_t payload_len, packet_len; + struct batadv_priv *bat_priv; int err = 0; + tp_vars = container_of(work, struct batadv_tp_vars, test_work); + bat_priv = tp_vars->bat_priv; + if (unlikely(tp_vars->role != BATADV_TP_SENDER)) { err = BATADV_TP_REASON_DST_UNREACHABLE; tp_vars->reason = err; @@ -901,40 +906,17 @@ static int batadv_tp_send(void *arg) batadv_tp_sender_cleanup(bat_priv, tp_vars); batadv_tp_vars_put(tp_vars); - - do_exit(0); } /** - * batadv_tp_start_kthread() - start new thread which manages the tp meter - * sender + * batadv_tp_start_work - start new thread which manages the tp meter sender * @tp_vars: the private data of the current TP meter session */ -static void batadv_tp_start_kthread(struct batadv_tp_vars *tp_vars) +static void batadv_tp_start_work(struct batadv_tp_vars *tp_vars) { - struct task_struct *kthread; - struct batadv_priv *bat_priv = tp_vars->bat_priv; - u32 session_cookie; - - kref_get(&tp_vars->refcount); - kthread = kthread_create(batadv_tp_send, tp_vars, "kbatadv_tp_meter"); - if (IS_ERR(kthread)) { - session_cookie = batadv_tp_session_cookie(tp_vars->session, - tp_vars->icmp_uid); - pr_err("batadv: cannot create tp meter kthread\n"); - batadv_tp_batctl_error_notify(BATADV_TP_REASON_MEMORY_ERROR, - tp_vars->other_end, - bat_priv, session_cookie); - - /* drop reserved reference for kthread */ - batadv_tp_vars_put(tp_vars); - - /* cleanup of failed tp meter variables */ - batadv_tp_sender_cleanup(bat_priv, tp_vars); - return; - } - - wake_up_process(kthread); + /* init work item that will actually execute the test and schedule it */ + INIT_WORK(&tp_vars->test_work, batadv_tp_send); + queue_work(batadv_tp_meter_queue, &tp_vars->test_work); } /** @@ -1053,13 +1035,10 @@ void batadv_tp_start(struct batadv_priv *bat_priv, const u8 *dst, /* init work item for finished tp tests */ INIT_DELAYED_WORK(&tp_vars->finish_work, batadv_tp_sender_finish); - /* start tp kthread. This way the write() call issued from userspace can - * happily return and avoid to block + /* schedule the tp worker. This way the write() call issued from + * userspace can happily return and avoid to block */ - batadv_tp_start_kthread(tp_vars); - - /* don't return reference to new tp_vars */ - batadv_tp_vars_put(tp_vars); + batadv_tp_start_work(tp_vars); } /** @@ -1498,8 +1477,26 @@ void batadv_tp_meter_recv(struct batadv_priv *bat_priv, struct sk_buff *skb) /** * batadv_tp_meter_init() - initialize global tp_meter structures + * + * Return: 0 on success, -ENOMEM if the tp_meter queue allocation fails */ -void __init batadv_tp_meter_init(void) +int __init batadv_tp_meter_init(void) { get_random_bytes(batadv_tp_prerandom, sizeof(batadv_tp_prerandom)); + + batadv_tp_meter_queue = alloc_ordered_workqueue("bat_tp_meter", 0); + if (!batadv_tp_meter_queue) + return -ENOMEM; + + return 0; +} + +/** + * batadv_tp_meter_destroy() - destroy tp meter memory allocations + */ +void batadv_tp_meter_destroy(void) +{ + flush_workqueue(batadv_tp_meter_queue); + destroy_workqueue(batadv_tp_meter_queue); + batadv_tp_meter_queue = NULL; } diff --git a/net/batman-adv/tp_meter.h b/net/batman-adv/tp_meter.h index 68e60097..ab0bde26 100644 --- a/net/batman-adv/tp_meter.h +++ b/net/batman-adv/tp_meter.h @@ -25,7 +25,8 @@ struct sk_buff; -void batadv_tp_meter_init(void); +int batadv_tp_meter_init(void); +void batadv_tp_meter_destroy(void); void batadv_tp_start(struct batadv_priv *bat_priv, const u8 *dst, u32 test_length, u32 *cookie); void batadv_tp_stop(struct batadv_priv *bat_priv, const u8 *dst, diff --git a/net/batman-adv/types.h b/net/batman-adv/types.h index 360357f8..baae5206 100644 --- a/net/batman-adv/types.h +++ b/net/batman-adv/types.h @@ -1354,6 +1354,9 @@ struct batadv_tp_vars { /** @finish_work: work item for the finishing procedure */ struct delayed_work finish_work; + /** @test_work: work item for the test process */ + struct work_struct test_work; + /** @test_length: test length in milliseconds */ u32 test_length;