From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from dpdk.org (dpdk.org [92.243.14.124]) by inbox.dpdk.org (Postfix) with ESMTP id 64A4FA0518 for ; Fri, 24 Jul 2020 14:07:18 +0200 (CEST) Received: from [92.243.14.124] (localhost [127.0.0.1]) by dpdk.org (Postfix) with ESMTP id 5E3771BFE7; Fri, 24 Jul 2020 14:07:18 +0200 (CEST) Received: from mail-wm1-f52.google.com (mail-wm1-f52.google.com [209.85.128.52]) by dpdk.org (Postfix) with ESMTP id C98C61C13A for ; Fri, 24 Jul 2020 14:07:17 +0200 (CEST) Received: by mail-wm1-f52.google.com with SMTP id o8so7748978wmh.4 for ; Fri, 24 Jul 2020 05:07:17 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=VWHhFD65saCHTq/ZPP+EoqC2vH3QIo3SCYOoKVECniM=; b=NhbJVJHRFMSXMY6u4Ne39Nd0aMl4KStRYg8VQyDX72OgPio3edpWlwVihvFQlPJ2O/ W9m3+Vi2pw0V2rtID5UM4sUQhWU/NLzw0VV8RFhpGne1vACUTxwf73bw7AbXQcH2Xaev /VuONlKEvvb425axehgyQ/indo4yjfBRgFJu+g5afjsu9k8SlWH3mcXalQAggvQHekOq YbhFKCjJCTOmokCvSaKiA5/qf2nnmeQBkhTMtW0zXj/kQHbHFlnu6hlE8NdJYFo33dR+ 9yQzqXZjnsHyyxfv9nwQl7MBf6qSDPF+iGw32AfypFZiu2eyStrpg382XYceBAwHaGRp Q+iA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=VWHhFD65saCHTq/ZPP+EoqC2vH3QIo3SCYOoKVECniM=; b=XlZeq05WRjLwmu/8E2KGHH15M3T7bPsfIaEpHwV8wqiLC9seDOx8aoleWbwpmfU0LT XMKm2NqetdcS36lEJ+IDsztY7Kyp4+zB4T5ax11kTI/jR6Z6LJFFyPKyKA0nbjbjNBC1 J3AwAq1cXb2So28awpmZrU64dCT4m3ebYMc7cKCa+zHSXC86XmhwYt4M3T3dDCiDHTuF kgXNk79i7PT1I75jHiSXbecm54fqYoHa7uUcAW4c/rpzbknmRUV1F6N5Qano7nVyyJh2 3oY8TlGD19QoxP4kjwhIIMhVl3FUkgbm573Jxf3n07u8WCw08lpQGWxpmSPoQiDpBoSA o3gw== X-Gm-Message-State: AOAM532IeclUKtdpfRFrQbXIGneGsTvMnje2t1qBIPhvT/2CpoQUe4y1 BGOXy2S15qQY/g+wLjqqtWs= X-Google-Smtp-Source: ABdhPJwVH1hQQv0SZGmg7MDgqB45BI30sZmw/ZytdVTOmb0wuiCrwytGoIMACt6gGrGsHWZM117Icg== X-Received: by 2002:a7b:ca57:: with SMTP id m23mr8271670wml.35.1595592437516; Fri, 24 Jul 2020 05:07:17 -0700 (PDT) Received: from localhost ([2a01:4b00:f419:6f00:7a8e:ed70:5c52:ea3]) by smtp.gmail.com with ESMTPSA id k204sm6734544wma.21.2020.07.24.05.07.15 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 24 Jul 2020 05:07:16 -0700 (PDT) From: luca.boccassi@gmail.com To: Phil Yang Cc: Dharmik Thakkar , Ruifeng Wang , Erik Gabriel Carrillo , dpdk stable Date: Fri, 24 Jul 2020 12:58:58 +0100 Message-Id: <20200724120030.1863487-100-luca.boccassi@gmail.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200724120030.1863487-1-luca.boccassi@gmail.com> References: <20200724120030.1863487-1-luca.boccassi@gmail.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Subject: [dpdk-stable] patch 'eventdev: fix race condition on timer list counter' has been queued to stable release 19.11.4 X-BeenThere: stable@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: patches for DPDK stable branches List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: stable-bounces@dpdk.org Sender: "stable" Hi, FYI, your patch has been queued to stable release 19.11.4 Note it hasn't been pushed to http://dpdk.org/browse/dpdk-stable yet. It will be pushed if I get no objections before 07/26/20. So please shout if anyone has objections. Also note that after the patch there's a diff of the upstream commit vs the patch applied to the branch. This will indicate if there was any rebasing needed to apply to the stable branch. If there were code changes for rebasing (ie: not only metadata diffs), please double check that the rebase was correctly done. Thanks. Luca Boccassi --- >From b01bf3ceeeb3bfe4c1146cb58f92362f279f11f6 Mon Sep 17 00:00:00 2001 From: Phil Yang Date: Tue, 7 Jul 2020 23:54:50 +0800 Subject: [PATCH] eventdev: fix race condition on timer list counter [ upstream commit aceb737d6f3210556a139514d304bf8f315a043f ] The n_poll_lcores counter and poll_lcore array are shared between lcores and the update of these variables are out of the protection of spinlock on each lcore timer list. The read-modify-write operations of the counter are not atomic, so it has the potential of race condition between lcores. Use c11 atomics with RELAXED ordering to prevent confliction. Fixes: cc7b73ea9e3b ("eventdev: add new software timer adapter") Signed-off-by: Phil Yang Reviewed-by: Dharmik Thakkar Reviewed-by: Ruifeng Wang Acked-by: Erik Gabriel Carrillo --- lib/librte_eventdev/rte_event_timer_adapter.c | 16 ++++++++++++---- 1 file changed, 12 insertions(+), 4 deletions(-) diff --git a/lib/librte_eventdev/rte_event_timer_adapter.c b/lib/librte_eventdev/rte_event_timer_adapter.c index 161e21a68..76885972e 100644 --- a/lib/librte_eventdev/rte_event_timer_adapter.c +++ b/lib/librte_eventdev/rte_event_timer_adapter.c @@ -579,6 +579,7 @@ swtim_callback(struct rte_timer *tim) uint16_t nb_evs_invalid = 0; uint64_t opaque; int ret; + int n_lcores; opaque = evtim->impl_opaque[1]; adapter = (struct rte_event_timer_adapter *)(uintptr_t)opaque; @@ -601,8 +602,12 @@ swtim_callback(struct rte_timer *tim) "with immediate expiry value"); } - if (unlikely(rte_atomic16_test_and_set(&sw->in_use[lcore].v))) - sw->poll_lcores[sw->n_poll_lcores++] = lcore; + if (unlikely(rte_atomic16_test_and_set(&sw->in_use[lcore].v))) { + n_lcores = __atomic_fetch_add(&sw->n_poll_lcores, 1, + __ATOMIC_RELAXED); + __atomic_store_n(&sw->poll_lcores[n_lcores], lcore, + __ATOMIC_RELAXED); + } } else { EVTIM_BUF_LOG_DBG("buffered an event timer expiry event"); @@ -1007,6 +1012,7 @@ __swtim_arm_burst(const struct rte_event_timer_adapter *adapter, uint32_t lcore_id = rte_lcore_id(); struct rte_timer *tim, *tims[nb_evtims]; uint64_t cycles; + int n_lcores; #ifdef RTE_LIBRTE_EVENTDEV_DEBUG /* Check that the service is running. */ @@ -1029,8 +1035,10 @@ __swtim_arm_burst(const struct rte_event_timer_adapter *adapter, if (unlikely(rte_atomic16_test_and_set(&sw->in_use[lcore_id].v))) { EVTIM_LOG_DBG("Adding lcore id = %u to list of lcores to poll", lcore_id); - sw->poll_lcores[sw->n_poll_lcores] = lcore_id; - ++sw->n_poll_lcores; + n_lcores = __atomic_fetch_add(&sw->n_poll_lcores, 1, + __ATOMIC_RELAXED); + __atomic_store_n(&sw->poll_lcores[n_lcores], lcore_id, + __ATOMIC_RELAXED); } ret = rte_mempool_get_bulk(sw->tim_pool, (void **)tims, -- 2.20.1 --- Diff of the applied patch vs upstream commit (please double-check if non-empty: --- --- - 2020-07-24 12:53:52.411591249 +0100 +++ 0100-eventdev-fix-race-condition-on-timer-list-counter.patch 2020-07-24 12:53:48.343007503 +0100 @@ -1,8 +1,10 @@ -From aceb737d6f3210556a139514d304bf8f315a043f Mon Sep 17 00:00:00 2001 +From b01bf3ceeeb3bfe4c1146cb58f92362f279f11f6 Mon Sep 17 00:00:00 2001 From: Phil Yang Date: Tue, 7 Jul 2020 23:54:50 +0800 Subject: [PATCH] eventdev: fix race condition on timer list counter +[ upstream commit aceb737d6f3210556a139514d304bf8f315a043f ] + The n_poll_lcores counter and poll_lcore array are shared between lcores and the update of these variables are out of the protection of spinlock on each lcore timer list. The read-modify-write operations of the counter @@ -11,7 +13,6 @@ Use c11 atomics with RELAXED ordering to prevent confliction. Fixes: cc7b73ea9e3b ("eventdev: add new software timer adapter") -Cc: stable@dpdk.org Signed-off-by: Phil Yang Reviewed-by: Dharmik Thakkar @@ -22,10 +23,10 @@ 1 file changed, 12 insertions(+), 4 deletions(-) diff --git a/lib/librte_eventdev/rte_event_timer_adapter.c b/lib/librte_eventdev/rte_event_timer_adapter.c -index 232180326..370ea40a7 100644 +index 161e21a68..76885972e 100644 --- a/lib/librte_eventdev/rte_event_timer_adapter.c +++ b/lib/librte_eventdev/rte_event_timer_adapter.c -@@ -583,6 +583,7 @@ swtim_callback(struct rte_timer *tim) +@@ -579,6 +579,7 @@ swtim_callback(struct rte_timer *tim) uint16_t nb_evs_invalid = 0; uint64_t opaque; int ret; @@ -33,7 +34,7 @@ opaque = evtim->impl_opaque[1]; adapter = (struct rte_event_timer_adapter *)(uintptr_t)opaque; -@@ -605,8 +606,12 @@ swtim_callback(struct rte_timer *tim) +@@ -601,8 +602,12 @@ swtim_callback(struct rte_timer *tim) "with immediate expiry value"); } @@ -48,7 +49,7 @@ } else { EVTIM_BUF_LOG_DBG("buffered an event timer expiry event"); -@@ -1011,6 +1016,7 @@ __swtim_arm_burst(const struct rte_event_timer_adapter *adapter, +@@ -1007,6 +1012,7 @@ __swtim_arm_burst(const struct rte_event_timer_adapter *adapter, uint32_t lcore_id = rte_lcore_id(); struct rte_timer *tim, *tims[nb_evtims]; uint64_t cycles; @@ -56,7 +57,7 @@ #ifdef RTE_LIBRTE_EVENTDEV_DEBUG /* Check that the service is running. */ -@@ -1033,8 +1039,10 @@ __swtim_arm_burst(const struct rte_event_timer_adapter *adapter, +@@ -1029,8 +1035,10 @@ __swtim_arm_burst(const struct rte_event_timer_adapter *adapter, if (unlikely(rte_atomic16_test_and_set(&sw->in_use[lcore_id].v))) { EVTIM_LOG_DBG("Adding lcore id = %u to list of lcores to poll", lcore_id);