From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: <Andriy.Berestovskyy@cavium.com> Received: from NAM03-CO1-obe.outbound.protection.outlook.com (mail-co1nam03on0083.outbound.protection.outlook.com [104.47.40.83]) by dpdk.org (Postfix) with ESMTP id CF0492A62 for <dev@dpdk.org>; Mon, 24 Apr 2017 16:50:48 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=CAVIUMNETWORKS.onmicrosoft.com; s=selector1-cavium-com; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version; bh=74LVPJ30tnnvqwZ0Rh+GNxV539u6svUq6uXfrC05k4I=; b=P6RKNH6h+8rBm2iu3ux5riJsL/veC7dejE8w99YtkvggjqKB0CuxzQZA1Apm4n8URgsBH0F1n8sFlUCy0gtRII4GQf10NiE6uV837tilW8BNVsorhIPAeG+5g+7JmgH5w7N92oU0ysvVJ8ypJtIcDmqkQPoOsUJAt5IgVHAm8Lw= Authentication-Results: dpdk.org; dkim=none (message not signed) header.d=none;dpdk.org; dmarc=none action=none header.from=caviumnetworks.com; Received: from [10.0.0.75] (31.172.191.173) by CY4PR07MB3511.namprd07.prod.outlook.com (10.171.252.156) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.1047.13; Mon, 24 Apr 2017 14:50:46 +0000 To: Thomas Monjalon <thomas@monjalon.net>, Bruce Richardson <bruce.richardson@intel.com> References: <1490288768-8114-1-git-send-email-Andriy.Berestovskyy@cavium.com> <2875009.PBUn9ZmEvk@xps13> <40c13c68-aadf-1665-a301-7d74be3017cd@caviumnetworks.com> <2079307.yoZvx5qzNF@xps> Cc: dev@dpdk.org From: Andriy Berestovskyy <Andriy.Berestovskyy@caviumnetworks.com> Message-ID: <abf49e30-6e40-641b-f668-dfd26c9be689@caviumnetworks.com> Date: Mon, 24 Apr 2017 16:50:37 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.8.0 MIME-Version: 1.0 In-Reply-To: <2079307.yoZvx5qzNF@xps> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit X-Originating-IP: [31.172.191.173] X-ClientProxiedBy: VI1P195CA0003.EURP195.PROD.OUTLOOK.COM (10.175.187.13) To CY4PR07MB3511.namprd07.prod.outlook.com (10.171.252.156) X-MS-PublicTrafficType: Email X-MS-Office365-Filtering-Correlation-Id: f9e41dd4-0b70-47ef-e4da-08d48b214acd X-Microsoft-Antispam: UriScan:; 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Yes, we pass the value to the PMD, which might check the value and return an error. >> Nevertheless, we can fix the false comment and have a default for the >> jumbos, which is beneficial for the apps/examples. > > The examples are using a hardcoded value, so they need to be fixed > anyway. We might change the hardcoded values to zeros once the patch is in. This will make the examples a bit more clear. > This ethdev patch is about a behaviour change of the API. The behaviour was not documented, so IMO it is not an issue. > It is about considering 0 as a request for default value > and return an error if a value cannot be set. Right. > It will require more agreements and changes in the drivers > for returning an error where appropriate. IMO the changes are transparent for the PMDs (please see below), but it might affect some applications. Here is the change in API behaviour: Before the patch: jumbo == 0, max_rx_pkt_len == 0, RESULT: max_rx_pkt_len = ETHER_MAX_LEN jumbo == 0, max_rx_pkt_len == 10, RESULT: max_rx_pkt_len = ETHER_MAX_LEN jumbo == 0, max_rx_pkt_len == 1200, RESULT: max_rx_pkt_len = 1200 jumbo == 0, max_rx_pkt_len == 9K, RESULT: max_rx_pkt_len = ETHER_MAX_LEN jumbo == 1, max_rx_pkt_len == 0, RESULT: ERROR jumbo == 1, max_rx_pkt_len == 10, RESULT: ERROR jumbo == 1, max_rx_pkt_len == 1200, RESULT: max_rx_pkt_len = 1200 jumbo == 1, max_rx_pkt_len == 9K, RESULT: ERROR or max_rx_pkt_len = 9K jumbo == 1, max_rx_pkt_len == 90K, RESULT: ERROR After the patch: jumbo == 0, max_rx_pkt_len == 0, RESULT: max_rx_pkt_len = ETHER_MAX_LEN jumbo == 0, max_rx_pkt_len == 10, RESULT: ERROR (changed) jumbo == 0, max_rx_pkt_len == 1200, RESULT: max_rx_pkt_len = 1200 jumbo == 0, max_rx_pkt_len == 9K, RESULT: ERROR (changed) jumbo == 1, max_rx_pkt_len == 0, RESULT: max_rx_pkt_len = dev_info() jumbo == 1, max_rx_pkt_len == 10, RESULT: ERROR jumbo == 1, max_rx_pkt_len == 1200, RESULT: max_rx_pkt_len = 1200 jumbo == 1, max_rx_pkt_len == 9K, RESULT: ERROR or max_rx_pkt_len = 9K jumbo == 1, max_rx_pkt_len == 90K, RESULT: ERROR Only the apps which requested too small or too big normal frames will be affected. In most cases it will be rather an error in the app... Also I have looked through all the PMDs to confirm they are not affected. Here is the summary: af_packet configure() does not use max_rx_pkt_len info() returns max_rx_pktlen = ETH_FRAME_LEN (1514) ark configure() does not use max_rx_pkt_len info() returns max_rx_pktlen = ETH_FRAME_LEN (16K - 128) avp configure() does not use max_rx_pkt_len info() returns max_rx_pktlen = avp->max_rx_pkt_len rx_queue_setup() uses max_rx_pkt_len for scattering bnx2x configure() uses max_rx_pkt_len to set internal mtu info() returns max_rx_pktlen = BNX2X_MAX_RX_PKT_LEN (15872) bnxt configure() uses max_rx_pkt_len to set internal mtu info() returns max_rx_pktlen = BNXT_MAX_MTU + ETHER_HDR_LEN + ETHER_CRC_LEN + VLAN_TAG_SIZE (9000 + 14 + 4 + 4) bonding configure() does not use max_rx_pkt_len info() returns max_rx_pktlen = internals->candidate_max_rx_pktlen or ETHER_MAX_JUMBO_FRAME_LEN (0x3F00) cxgbe configure() does not use max_rx_pkt_len info() returns max_rx_pktlen = CXGBE_MAX_RX_PKTLEN (9000 + 14 + 4) rx_queue_setup() checks max_rx_pkt_len boundaries dpaa2 configure() does not use max_rx_pkt_len info() returns max_rx_pktlen = DPAA2_MAX_RX_PKT_LEN (10240) e1000 (em) configure() does not use max_rx_pkt_len info() returns max_rx_pktlen = em_get_max_pktlen() (0x2412, 0x1000, 1518, 0x3f00, depends on model) e1000 (igb) configure() does not use max_rx_pkt_len info() returns max_rx_pktlen = 0x3fff start() writes max_rx_pkt_len to HW for jumbo frames only start() uses max_rx_pkt_len for scattering ena configure() does not use max_rx_pkt_len info() returns max_rx_pktlen = adapter->max_mtu start() checks max_rx_pkt_len boundaries enic configure() does not use max_rx_pkt_len info() returns max_rx_pktlen = enic->max_mtu + 14 + 4 fm10k configure() does not use max_rx_pkt_len info() returns max_rx_pktlen = FM10K_MAX_PKT_SIZE (15 * 1024) start() uses max_rx_pkt_len for scattering i40e configure() does not use max_rx_pkt_len info() returns max_rx_pktlen = I40E_FRAME_SIZE_MAX (9728) rx_queue_config() checks max_rx_pkt_len boundaries ixgbe configure() does not use max_rx_pkt_len info() returns max_rx_pktlen = 15872 (9728 for vf) start() writes max_rx_pkt_len to HW for jumbo frames only start() uses max_rx_pkt_len for scattering kni configure() does not use max_rx_pkt_len info() returns max_rx_pktlen = UINT32_MAX liquidio configure() does not use max_rx_pkt_len info() returns max_rx_pktlen = LIO_MAX_RX_PKTLEN (64K) start() checks max_rx_pkt_len boundaries mlx4 configure() uses max_rx_pkt_len for scattering info() returns max_rx_pktlen = 65536 mlx5 configure() uses max_rx_pkt_len for scattering info() returns max_rx_pktlen = 65536 nfp configure() does not use max_rx_pkt_len info() returns max_rx_pktlen = hw->mtu null configure() does not use max_rx_pkt_len info() returns max_rx_pktlen = (uint32_t)-1 pcap configure() does not use max_rx_pkt_len info() returns max_rx_pktlen = (uint32_t)-1 qede configure() uses max_rx_pkt_len for scattering + internal data info() returns max_rx_pktlen = ETH_TX_MAX_NON_LSO_PKT_LEN (9700 - 4 - 4 - 12 - 8) ring configure() does not use max_rx_pkt_len info() returns max_rx_pktlen = (uint32_t)-1 sfc configure() uses max_rx_pkt_len to set internal data info() returns max_rx_pktlen = EFX_MAC_PDU_MAX (9202 + 14 + 4 + 4 + 16) szedata2 configure() does not use max_rx_pkt_len info() returns max_rx_pktlen = (uint32_t)-1 tap configure() does not use max_rx_pkt_len info() returns max_rx_pktlen = ETHER_MAX_VLAN_FRAME_LEN (1518 + 4) thunderx configure() uses max_rx_pkt_len for scattering + sets internal mtu info() returns max_rx_pktlen = NIC_HW_MAX_FRS (9200) vhost configure() does not use max_rx_pkt_len info() returns max_rx_pktlen = (uint32_t)-1 virtio configure() does not use max_rx_pkt_len info() returns max_rx_pktlen = VIRTIO_MAX_RX_PKTLEN (9728U) vmxnet3 configure() does not use max_rx_pkt_len info() returns max_rx_pktlen = 16384; xenvirt configure() does not use max_rx_pkt_len info() returns max_rx_pktlen = 2048 Regards, Andriy