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 A1B15A04DD for ; Wed, 28 Oct 2020 11:55:54 +0100 (CET) Received: from [92.243.14.124] (localhost [127.0.0.1]) by dpdk.org (Postfix) with ESMTP id 97928CAC5; Wed, 28 Oct 2020 11:55:53 +0100 (CET) Received: from mail-wr1-f68.google.com (mail-wr1-f68.google.com [209.85.221.68]) by dpdk.org (Postfix) with ESMTP id B3EF1CAC5 for ; Wed, 28 Oct 2020 11:55:52 +0100 (CET) Received: by mail-wr1-f68.google.com with SMTP id t9so5137691wrq.11 for ; Wed, 28 Oct 2020 03:55:52 -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=HBoBceIHIMz8O2Q00EpTX/vWT/Y7LfY22ZxCrVgpS4Y=; b=nEbnNXsIsxRjUCT0oYKb4QonPTbKzDd49tc0UX3q2zErB81WPDH//tgNjPogVHzjAb MvPHAKNEeydm+XasNU2oqxIMulrZWvR+xrD0/enON9pcLxWk3CEDa4NMNo1zOxKewxP0 z3HscTjwZeVhTJ0ihr6b+PMqlz7PmAOpaKB12I0YE7neUtCfinJDYpAT+N2SsLnHAck0 bqg6Yh/pJZM5QweLkkR6bFRNjQm2gIdvpVIVDm+KqLFB0S+w/Hzck0UEyVsfuE99Py40 ZqhZFfvIv4v9jtAAxe0YLigcyxs9+sLls1EaC2ZFjEQSqcPbXgb59fX/gyzpHsgot4Nf nrJg== 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=HBoBceIHIMz8O2Q00EpTX/vWT/Y7LfY22ZxCrVgpS4Y=; b=Mr5qacIkVgttNEfUbUCAEUyhlfkkRw9DTYhmE17kYP584Qmlbe7ONpaj3vn/mY8PwJ b88YQs4kX2MXvW107QHHCTxTdI/SZOTSpS6DI9ct2YhxAauRv5y/t5GMqj4SbnCFFc/M pQLUh1hvPGhL3gCdFS62NJoE4OQw2M9e1xECdq5J+ZtoTB2rL+pvk2aWnzaHHmSn/hE8 oVBo1gi7G4teyz5nsa2psiWh2GDLQO1i+bh+KfP1Znfq4fBb+4JNLHGvKGAgA6OqMmIV IVmWMarYr6EXVGsFHVUSY34bIH8D5m3G8qBXbq24vM+BpHsFpKBEO6BFYiepwyWCSBnu w4Ug== X-Gm-Message-State: AOAM530CHOPgfjxe7XGmsY8DDLoIthCaVpaT+J07zT+uh/QvGGJ2rdw1 AFXohsJn6pHKnrwnPtwyJcA= X-Google-Smtp-Source: ABdhPJxbweaFHzWz1mSNr7oeAeVnX/uTpYVgLO7duYMc6qnmxOkCKD2lxv74PxW3B+APPZbwTneXwQ== X-Received: by 2002:adf:f80a:: with SMTP id s10mr8203230wrp.275.1603882551473; Wed, 28 Oct 2020 03:55:51 -0700 (PDT) Received: from localhost ([88.98.246.218]) by smtp.gmail.com with ESMTPSA id b190sm5918534wmd.35.2020.10.28.03.55.50 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 28 Oct 2020 03:55:50 -0700 (PDT) From: luca.boccassi@gmail.com To: Lukasz Wojciechowski Cc: David Hunt , dpdk stable Date: Wed, 28 Oct 2020 10:45:42 +0000 Message-Id: <20201028104606.3504127-183-luca.boccassi@gmail.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20201028104606.3504127-1-luca.boccassi@gmail.com> References: <20201028104606.3504127-1-luca.boccassi@gmail.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Subject: [dpdk-stable] patch 'distributor: fix handshake deadlock' has been queued to stable release 19.11.6 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 19.11.6 Note it hasn't been pushed to http://dpdk.org/browse/dpdk-stable yet. It will be pushed if I get no objections before 10/30/20. 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 e5fc315a5f05aaa14b099618a4076d8dcc82f7e1 Mon Sep 17 00:00:00 2001 From: Lukasz Wojciechowski Date: Sat, 17 Oct 2020 05:06:46 +0200 Subject: [PATCH] distributor: fix handshake deadlock [ upstream commit 5acce079e7dc773c17bf2043fc18106392b4a863 ] Synchronization of data exchange between distributor and worker cores is based on 2 handshakes: retptr64 for returning mbufs from workers to distributor and bufptr64 for passing mbufs to workers. Without proper order of verifying those 2 handshakes a deadlock may occur. This can happen when worker core wants to return back mbufs and waits for retptr handshake to be cleared while distributor core waits for bufptr to send mbufs to worker. This can happen as worker core first returns mbufs to distributor and later gets new mbufs, while distributor first releases mbufs to worker and later handle returning packets. This patch fixes possibility of the deadlock by always taking care of returning packets first on the distributor side and handling packets while waiting to release new. Fixes: 775003ad2f96 ("distributor: add new burst-capable library") Signed-off-by: Lukasz Wojciechowski Acked-by: David Hunt --- lib/librte_distributor/rte_distributor.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/lib/librte_distributor/rte_distributor.c b/lib/librte_distributor/rte_distributor.c index c6b19a3886..d6d4350a28 100644 --- a/lib/librte_distributor/rte_distributor.c +++ b/lib/librte_distributor/rte_distributor.c @@ -319,12 +319,14 @@ release(struct rte_distributor *d, unsigned int wkr) struct rte_distributor_buffer *buf = &(d->bufs[wkr]); unsigned int i; + handle_returns(d, wkr); + /* Sync with worker on GET_BUF flag */ while (!(__atomic_load_n(&(d->bufs[wkr].bufptr64[0]), __ATOMIC_ACQUIRE) - & RTE_DISTRIB_GET_BUF)) + & RTE_DISTRIB_GET_BUF)) { + handle_returns(d, wkr); rte_pause(); - - handle_returns(d, wkr); + } buf->count = 0; @@ -374,6 +376,7 @@ rte_distributor_process(struct rte_distributor *d, /* Flush out all non-full cache-lines to workers. */ for (wid = 0 ; wid < d->num_workers; wid++) { /* Sync with worker on GET_BUF flag. */ + handle_returns(d, wid); if (__atomic_load_n(&(d->bufs[wid].bufptr64[0]), __ATOMIC_ACQUIRE) & RTE_DISTRIB_GET_BUF) { release(d, wid); -- 2.20.1 --- Diff of the applied patch vs upstream commit (please double-check if non-empty: --- --- - 2020-10-28 10:35:17.392993092 +0000 +++ 0183-distributor-fix-handshake-deadlock.patch 2020-10-28 10:35:11.796834322 +0000 @@ -1,8 +1,10 @@ -From 5acce079e7dc773c17bf2043fc18106392b4a863 Mon Sep 17 00:00:00 2001 +From e5fc315a5f05aaa14b099618a4076d8dcc82f7e1 Mon Sep 17 00:00:00 2001 From: Lukasz Wojciechowski Date: Sat, 17 Oct 2020 05:06:46 +0200 Subject: [PATCH] distributor: fix handshake deadlock +[ upstream commit 5acce079e7dc773c17bf2043fc18106392b4a863 ] + Synchronization of data exchange between distributor and worker cores is based on 2 handshakes: retptr64 for returning mbufs from workers to distributor and bufptr64 for passing mbufs to workers. @@ -21,7 +23,6 @@ packets while waiting to release new. Fixes: 775003ad2f96 ("distributor: add new burst-capable library") -Cc: stable@dpdk.org Signed-off-by: Lukasz Wojciechowski Acked-by: David Hunt