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 D5A0EA04DB; Thu, 15 Oct 2020 12:49:21 +0200 (CEST) Received: from [92.243.14.124] (localhost [127.0.0.1]) by dpdk.org (Postfix) with ESMTP id A92661DEED; Thu, 15 Oct 2020 12:49:20 +0200 (CEST) Received: from mailgw02.pantheon.sk (mailgw01.pantheon.sk [46.229.239.26]) by dpdk.org (Postfix) with ESMTP id 122C31DE90 for ; Thu, 15 Oct 2020 12:49:18 +0200 (CEST) Received: from mailgw02.pantheon.sk (localhost.localdomain [127.0.0.1]) by mailgw02.pantheon.sk (Proxmox) with ESMTP id D1E451833B1 for ; Thu, 15 Oct 2020 12:49:17 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=pantheon.tech; h=cc:content-type:content-type:date:from:from:message-id :mime-version:reply-to:subject:subject:to:to; s=dkim; bh=cJIqgkd fR+Yvi5I/vSTSOvqOAWecvGTIgNNug/6F9SA=; b=RE8PtoivRaYb0H5LYbglAlT 9o85eY0fNT93HzA17/v67AQtBiTNX4BGa2kiXwYJC9zOrkPu1Wgd1GVbbdZmcK8n oWELqYpv3OYrKV1gDb2NSfgrnWmr/zPp3YROG03TBN8ZwQrAZ6T5tOAwzdtOKR5w kGaqvQ0xT3a8MfHUYqYLv/G7anj7M1AR4BtWzUM0RRgM2S7mhrG/9UUa1L3nzNIG lAey0Zk3dzT7Mex9EM3SsCQmTmUf2fgbhof0w/kQ09zMubJVGtdPwEnMapN2+MMs YUl/UbHQv2FqnwgkQWKw1KaVcHcOaw7vyeU4xAUiODzRnNi0pab541FfIst5TlA= = From: =?iso-8859-2?Q?Juraj_Linke=B9?= To: "dev@dpdk.org" Thread-Topic: Minimun value of RTE_MAX_LCORE Thread-Index: Adai4Mdyw2EsKcszTni68vlLSuHUHQ== Date: Thu, 15 Oct 2020 10:49:17 +0000 Message-ID: <317a9b0f7130448190e2391150bd0f67@pantheon.tech> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [10.101.4.10] MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-2" Content-Transfer-Encoding: quoted-printable X-Content-Filtered-By: Mailman/MimeDel 2.1.15 Subject: [dpdk-dev] Minimun value of RTE_MAX_LCORE X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" Hi dpdk devs, Is there a constraint on how low RTE_MAX_LCORE can be? I'm implementing a d= iscovery mechanism that sets RTE_MAX_LCORE according to the number of host = cores, but I'm hitting errors when the values are low: https://travis-ci.com/github/jlinkes/dpdk/jobs/399596828 Message: Found 2 cores Message: Found 1 numa nodes ../app/test/test_rcu_qsbr.c:296:54: error: iteration 2 invokes undefined be= havior [-Werror=3Daggressive-loop-optimizations] ../app/test/test_rcu_qsbr.c:315:55: error: array subscript is above array b= ounds [-Werror=3Darray-bounds] All VM jobs failed in that Travis build. Travis VMs only have 2 cores, so I= tried to put a bound on the build. I set it to 4 and all jobs except GCC s= hared lib jobs passed, which still threw iteration 4 invokes undefined beha= vior error: https://travis-ci.com/github/jlinkes/dpdk/jobs/400004089 ../examples/performance-thread/l3fwd-thread/main.c:2338:34: error: iteratio= n 4 invokes undefined behavior [-Werror=3Daggressive-loop-optimizations] This happens for number of cores < 32 and looks like a limitation unique to= l3fwd (with cores between 4 and 32 - I didn't see the error elsewhere). Should I use the bound or are these legitimate errors? The fact that only G= CC (and not clang) shared lib jobs failed is also suspicious. Thanks, Juraj