From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mailout1.w1.samsung.com (mailout1.w1.samsung.com [210.118.77.11]) by dpdk.org (Postfix) with ESMTP id 5EC631B8B1 for ; Wed, 19 Dec 2018 17:28:11 +0100 (CET) Received: from eucas1p2.samsung.com (unknown [182.198.249.207]) by mailout1.w1.samsung.com (KnoxPortal) with ESMTP id 20181219162810euoutp014e9965aac4a8faaa829b316a0f364a25~xyMPEDkb31850518505euoutp01j for ; Wed, 19 Dec 2018 16:28:10 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 mailout1.w1.samsung.com 20181219162810euoutp014e9965aac4a8faaa829b316a0f364a25~xyMPEDkb31850518505euoutp01j DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=samsung.com; s=mail20170921; t=1545236890; bh=UbhN3GgosWu87MI4/FWqhJoPdmYAlaHDqfXyRFlQk4Y=; h=Subject:To:Cc:From:Date:In-Reply-To:References:From; b=QxZ7AaTt0EbjE99evAd/UTvSw8GFz+eywTuV+kWFYa/8lxEDrJDpVwIjWG9wfkyQY eBIvzzfJ1M0VFkNf2QYCeeKuCuj+ZCHmva4TfUcrjBbC/AgakGFMG/JlHyQwZA3w8K 8PWV7kQq60bVlEwbE4HnlNpWptTdeJgKzI1KDXLg= Received: from eusmges1new.samsung.com (unknown [203.254.199.242]) by eucas1p2.samsung.com (KnoxPortal) with ESMTP id 20181219162809eucas1p2b7918f1f0df4053ed190d716d74e2d66~xyMOszZsk2169521695eucas1p2L; Wed, 19 Dec 2018 16:28:09 +0000 (GMT) Received: from eucas1p1.samsung.com ( [182.198.249.206]) by eusmges1new.samsung.com (EUCPMTA) with SMTP id A9.FE.04441.9917A1C5; Wed, 19 Dec 2018 16:28:09 +0000 (GMT) Received: from eusmtrp2.samsung.com (unknown [182.198.249.139]) by eucas1p2.samsung.com (KnoxPortal) with ESMTPA id 20181219162809eucas1p20c79748fc84f56edf064a5356f868b40~xyMN3pKad2173421734eucas1p2G; Wed, 19 Dec 2018 16:28:09 +0000 (GMT) Received: from eusmgms1.samsung.com (unknown [182.198.249.179]) by eusmtrp2.samsung.com (KnoxPortal) with ESMTP id 20181219162808eusmtrp2eb8cf786417397e8e2cdb354eb3b00da~xyMNo8n1y2314223142eusmtrp2I; Wed, 19 Dec 2018 16:28:08 +0000 (GMT) X-AuditID: cbfec7f2-5e3ff70000001159-9f-5c1a7199320a Received: from eusmtip2.samsung.com ( [203.254.199.222]) by eusmgms1.samsung.com (EUCPMTA) with SMTP id CD.10.04284.8917A1C5; Wed, 19 Dec 2018 16:28:08 +0000 (GMT) Received: from [106.109.129.180] (unknown [106.109.129.180]) by eusmtip2.samsung.com (KnoxPortal) with ESMTPA id 20181219162808eusmtip2697d9d61f0de90b2c6f1850eee3697b7~xyMNFm9v92646926469eusmtip2D; Wed, 19 Dec 2018 16:28:08 +0000 (GMT) To: "Michael S. Tsirkin" , Maxime Coquelin Cc: dev@dpdk.org, tiwei.bie@intel.com, zhihong.wang@intel.com, jasowang@redhat.com, stable@dpdk.org From: Ilya Maximets Message-ID: <9051b057-23df-78d4-04e0-6d02fadbd015@samsung.com> Date: Wed, 19 Dec 2018 19:28:07 +0300 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.2.1 MIME-Version: 1.0 In-Reply-To: <20181219104947-mutt-send-email-mst@kernel.org> Content-Language: en-GB Content-Transfer-Encoding: 7bit X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFlrFKsWRmVeSWpSXmKPExsWy7djPc7ozC6ViDD6/Urd492k7k8WV9p/s FssufWayONa5h8Xi/69XrBb/Ov6wW2xt+M9ksfniJCYHDo9fC5ayeize85LJ4/2+q2wefVtW MQawRHHZpKTmZJalFunbJXBlHL11nK3gGlfFp+OTWBoY93F0MXJySAiYSCzufsvYxcjFISSw glHi2L5TrBDOF0aJORvfQDmfGSWu9t1hhWnZ0HoRqmU5o8Su67egnI+MEt3vTrKBVAkLeEos v7ebCcQWEYiUmDHnEZjNLJAq8WRJGwuIzSagI3Fq9RFGEJtXwE6id8oysDiLgKrE5TtdYNtE BSIkOu6vZoOoEZQ4OfMJUA0HB6eAjUR3sy7ESHGJpi8rWSFseYntb+cwg9wjIbCJXeLO3f3M EFe7SHxduYYJwhaWeHV8CzuELSPxf+d8qHi9xP2Wl4wQzR2MEtMP/YNK2EtseX2OHWQxs4Cm xPpd+iCmhICjxNsbPBAmn8SNt4IQJ/BJTNo2nRkizCvR0SYEMUNF4vfB5VDHSEncfPeZfQKj 0iwkf81C8swsJM/MQli7gJFlFaN4amlxbnpqsWFearlecWJucWleul5yfu4mRmAKOv3v+Kcd jF8vJR1iFOBgVOLhnRElFSPEmlhWXJl7iFGCg1lJhPeGCVCINyWxsiq1KD++qDQntfgQozQH i5I4bzXDg2ghgfTEktTs1NSC1CKYLBMHp1QDo1N26QyFOqWMvLkis7WEJsswmwvP+5fWt/zR qfIrZ17sL1XrCFZW0C3xTokVc1peZH7yWnP/rKYPL2+mPTmpf+WrleRWTsXAeTO+T9+9WoxX PW1Nr4Fi/L+bpowRAt2Cj+YUqoVua9hVO4tl/+2/O6LyFHM83z/6pb7YX0nKTOaj8MKjBg9u KbEUZyQaajEXFScCANRS/M89AwAA X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFtrHIsWRmVeSWpSXmKPExsVy+t/xe7ozCqViDHYd1LZ492k7k8WV9p/s FssufWayONa5h8Xi/69XrBb/Ov6wW2xt+M9ksfniJCYHDo9fC5ayeize85LJ4/2+q2wefVtW MQawROnZFOWXlqQqZOQXl9gqRRtaGOkZWlroGZlY6hkam8daGZkq6dvZpKTmZJalFunbJehl HL11nK3gGlfFp+OTWBoY93F0MXJySAiYSGxovcjYxcjFISSwlFHi+cYnjBAJKYkfvy6wQtjC En+udbFBFL1nlDh6v40dJCEs4Cmx/N5uJhBbRCBSYtm6BrBmZoFUif6Gx8wQDUcZJf5MegQ2 iU1AR+LU6iNgRbwCdhK9U5axgNgsAqoSl+90gdWICkRInH25DqpGUOLkzCdANRwcnAI2Et3N uhDz1SX+zLvEDGGLSzR9WckKYctLbH87h3kCo9AsJN2zkLTMQtIyC0nLAkaWVYwiqaXFuem5 xYZ6xYm5xaV56XrJ+bmbGIFxt+3Yz807GC9tDD7EKMDBqMTDOyNKKkaINbGsuDL3EKMEB7OS CO8NE6AQb0piZVVqUX58UWlOavEhRlOg3yYyS4km5wNTQl5JvKGpobmFpaG5sbmxmYWSOO95 g8ooIYH0xJLU7NTUgtQimD4mDk6pBsb+dzvDNm3rPm6+vzNv1YYf352tde/qqiydyKrIt31F 9UcRVgkVofmrG/lCPu3a2GyX63Cp4mXLogk+ks2FJxNlohsnrFy3JFx2W2+fX7/BUouFa3an xuZ9tXMJ2D//fNSi3jV5frrnxRv2NPdzdmk9L1qff4BLvvpF5Rs7t+Cmy9eC/xVsOa3EUpyR aKjFXFScCACpesfL0QIAAA== X-CMS-MailID: 20181219162809eucas1p20c79748fc84f56edf064a5356f868b40 X-Msg-Generator: CA Content-Type: text/plain; charset="utf-8" X-RootMTR: 20181219155100epcas1p4d88bb40eaed8e39df7af5f2d71122aec X-EPHeader: CA CMS-TYPE: 201P X-CMS-RootMailID: 20181219155100epcas1p4d88bb40eaed8e39df7af5f2d71122aec References: <20181219082113.24455-1-maxime.coquelin@redhat.com> <20181219104947-mutt-send-email-mst@kernel.org> Subject: Re: [dpdk-dev] [PATCH v2 0/4] vhost: add missing barriers, move prefetching 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: , X-List-Received-Date: Wed, 19 Dec 2018 16:28:11 -0000 On 19.12.2018 18:50, Michael S. Tsirkin wrote: > On Wed, Dec 19, 2018 at 09:21:09AM +0100, Maxime Coquelin wrote: >> This series adds missing read barriers after reading avail index >> for split ring and desc flags for packed ring. >> >> Also, it turns out that some descriptors prefetching are either >> badly placed, or useless, last part of the series fixes that. >> >> With the series applied, I get between 0 and 4% gain depending >> on the benchmark (testpmd txonly/rxonly/io). >> >> Thanks to Jason for reporting the missing read barriers. > > Acked-by: Michael S. Tsirkin > > But I wonder what effect this has on ARM where RMB isn't a NOP. > Ilya do you happen to have any data? Hi. My rough testing shows no significant performance difference on ARMv8. > >> Changes since v1: >> ================= >> - Drop volatile removal patch (Ilya) >> - Improve commit messages for RMB patches (Ilya) >> >> Maxime Coquelin (4): >> vhost: enforce avail index and desc read ordering >> vhost: enforce desc flags and content read ordering >> vhost: prefetch descriptor after the read barrier >> vhost: remove useless prefetch for packed ring descriptor >> >> lib/librte_vhost/virtio_net.c | 27 ++++++++++++++++++++++----- >> 1 file changed, 22 insertions(+), 5 deletions(-) >> >> -- >> 2.17.2 > >