From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from out5-smtp.messagingengine.com (out5-smtp.messagingengine.com [66.111.4.29]) by dpdk.org (Postfix) with ESMTP id 99D7591; Mon, 12 Nov 2018 10:22:00 +0100 (CET) Received: from compute1.internal (compute1.nyi.internal [10.202.2.41]) by mailout.nyi.internal (Postfix) with ESMTP id 2D37B21D2B; Mon, 12 Nov 2018 04:22:00 -0500 (EST) Received: from mailfrontend1 ([10.202.2.162]) by compute1.internal (MEProxy); Mon, 12 Nov 2018 04:22:00 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=monjalon.net; h= from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding:content-type; s=mesmtp; bh=6eFjavAqKci+vJqykEgSrPdveSxRpW2QUnqVp2YRqK0=; b=Buv5/7Xiv/Te /8vJBnXvicdXK6C1l5XuHdsTjkwWWz/LTy+ZVia/xf7Z0KWo+pl+0tjxwGEn6mI6 NaTUwrj9BcNAQPVj+EpeXQVRakx3Xpk43GtT4xL+TV66kctUDzu3To8NYsCu7Piv Hp5w6jV3BpgWqqJnlhHxZFNyfppFsJg= DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:content-transfer-encoding:content-type :date:from:in-reply-to:message-id:mime-version:references :subject:to:x-me-proxy:x-me-proxy:x-me-sender:x-me-sender :x-sasl-enc; s=fm1; bh=6eFjavAqKci+vJqykEgSrPdveSxRpW2QUnqVp2YRq K0=; b=WW4KrF3NgxTLTMsZ+5HFVoz7H6VK4VJK+e0bOGHq4S2QM83puGF7kgM9J dIKhK/wLfxCBNGQlBtW08OEjHogRnMaAif86TQz3sqqk5VGL+0+NNn/i9TTRNM8E uqZPFOEVqqlfHeE2JaO12p9bFny31CUYve5+dyu2lwausQ8YzUszzIAJEnFUw/cV VEY9qahmNGJ93f2yArWrj1jxT8BrhF0/jliwW8SSB+PSHHfsAUeUA0Iun/EbVmrP Uau6kwrs9kOVgxeDRcOMsOYuuDSvdjw0ux4UfSCcQRD6VQv8yHTWH5aeuVHPxbzO I8cAHxnhr9WiAcfUr0P5D9P7JRz3g== X-ME-Sender: X-ME-Proxy: Received: from xps.localnet (184.203.134.77.rev.sfr.net [77.134.203.184]) by mail.messagingengine.com (Postfix) with ESMTPA id B4654E407B; Mon, 12 Nov 2018 04:21:57 -0500 (EST) From: Thomas Monjalon To: Christian Ehrhardt Cc: "Ananyev, Konstantin" , Ferruh Yigit , Bruce Richardson , stable@dpdk.org, keith.wiles@intel.com, yskoh@mellanox.com, dev , Shahaf Shuler , anatoly.burakov@intel.com, justin.parus@microsoft.com, David Coronel , Josh Powers , Jay Vosburgh , Dan Streetman Date: Mon, 12 Nov 2018 10:21:56 +0100 Message-ID: <1966988.vJfdJNsEgr@xps> In-Reply-To: References: <20181023212318.43082-1-yskoh@mellanox.com> <14171327.rkP5k0YJWv@xps> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" Subject: Re: [dpdk-stable] AVX512 bug on SkyLake 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: , X-List-Received-Date: Mon, 12 Nov 2018 09:22:01 -0000 12/11/2018 10:09, Christian Ehrhardt: > > - vmovdqu8 xmm0,XMMWORD PTR [rax*8+0x6] > > + vmovdqu xmm0,XMMWORD PTR [rax*8+0x60] > > vinserti128 ymm0,ymm0,XMMWORD PTR [rax*8+0x70],0x1 > > vmovups XMMWORD PTR [rsi+0x60],xmm0 > > vextracti128 XMMWORD PTR [rsi+0x70],ymm0,0x1 > > > > > Not sure what causing compiler behaves that way. > > > BTW, looking though testpmd objdump output - it seems that only mlx5 driver > > > exhibits such problem (I didn't enable mlx4 actually, probably same problem here). > > > Which looks a bit weird to me. > > > > Yes it's weird. I don't see how the mlx5 code could influence > > the compiler to generate this bad code in AVX512 mode. > > Thomas you have all this set up, do you have any chance to test this > on the GCC's in Ubuntu 18.10 and 19.04 > If easy I'd love to see results wit hgcc-7 & gcc-8 as in Ubuntu 19.04 > (current -dev). > If the above is too hard, at least could you try the gcc-8 in Bionic > is 8.2.0-1ubuntu2~18.04 that is rather close. I already tested updated GCC 7 and 8 (it is the same result): https://bugs.dpdk.org/show_bug.cgi?id=97#c18 Versions are: gcc-7 (Ubuntu 7.3.0-27ubuntu1~18.04) 7.3.0 gcc-8 (Ubuntu 8.2.0-1ubuntu2~18.04) 8.2.0 > If you could share the simplified build options that you need to > reproduce that would help (at least me) - thanks in advance You just need to compile mlx5, nothing special.