From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mga11.intel.com (mga11.intel.com [192.55.52.93]) by dpdk.org (Postfix) with ESMTP id EDFED695D for ; Thu, 11 Oct 2018 11:04:20 +0200 (CEST) X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga004.fm.intel.com ([10.253.24.48]) by fmsmga102.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 11 Oct 2018 02:04:20 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.54,367,1534834800"; d="scan'208";a="96561637" Received: from aburakov-mobl1.ger.corp.intel.com (HELO [10.237.220.79]) ([10.237.220.79]) by fmsmga004.fm.intel.com with ESMTP; 11 Oct 2018 02:03:35 -0700 To: Shreyansh Jain Cc: ferruh.yigit@intel.com, dev@dpdk.org References: <20180925125423.7505-1-shreyansh.jain@nxp.com> <20180925125423.7505-4-shreyansh.jain@nxp.com> <894130a9-017c-348d-31f8-c4c23f517f25@nxp.com> <2d2e9008-fb5b-3ecd-2d2c-e86250f5d363@nxp.com> From: "Burakov, Anatoly" Message-ID: <5e153c76-6eaa-e6a5-28ed-7cec191d4581@intel.com> Date: Thu, 11 Oct 2018 10:03:35 +0100 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:52.0) Gecko/20100101 Thunderbird/52.9.1 MIME-Version: 1.0 In-Reply-To: <2d2e9008-fb5b-3ecd-2d2c-e86250f5d363@nxp.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 8bit Subject: Re: [dpdk-dev] [PATCH 3/5] common/dpaax: add library for PA VA translation table 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: Thu, 11 Oct 2018 09:04:21 -0000 On 09-Oct-18 11:45 AM, Shreyansh Jain wrote: > On Tuesday 25 September 2018 07:09 PM, Shreyansh Jain wrote: >> Hello Anatoly, >> >> On Tuesday 25 September 2018 06:58 PM, Burakov, Anatoly wrote: >>> On 25-Sep-18 1:54 PM, Shreyansh Jain wrote: >>>> A common library, valid for dpaaX drivers, which is used to maintain >>>> a local copy of PA->VA translations. >>>> >>>> In case of physical addressing mode (one of the option for FSLMC, and >>>> only option for DPAA bus), the addresses of descriptors Rx'd are >>>> physical. These need to be converted into equivalent VA for rte_mbuf >>>> and other similar calls. >>>> >>>> Using the rte_mem_virt2iova or rte_mem_virt2phy is expensive. This >>>> library is an attempt to reduce the overall cost associated with >>>> this translation. >>>> >>>> A small table is maintained, containing continuous entries >>>> representing a continguous physical range. Each of these entries >>>> stores the equivalent VA, which is fed during mempool creation, or >>>> memory allocation/deallocation callbacks. >>>> > > [...] > >> >>> >>> Also, a couple of nitpicks below. >>> >>>>   cosnfig/common_base                            |   5 + >>>>   config/common_linuxapp                        |   5 + >>>>   drivers/common/Makefile                       |   4 + >>>>   drivers/common/dpaax/Makefile                 |  31 ++ >>>>   drivers/common/dpaax/dpaax_iova_table.c       | 509 >>>> ++++++++++++++++++ >>>>   drivers/common/dpaax/dpaax_iova_table.h       | 104 ++++ >>>>   drivers/common/dpaax/dpaax_logs.h             |  39 ++ >>>>   drivers/common/dpaax/meson.build              |  12 + >>> >>> >>> >>>> +    DPAAX_DEBUG("Add: Found slot at (%"PRIu64")[(%zu)] for >>>> vaddr:(%p)," >>>> +            " phy(%"PRIu64"), len(%zu)", entry[i].start, e_offset, >>>> +            vaddr, paddr, length); >>>> +    return 0; >>>> +} >>>> + >>>> +int >>>> +dpaax_iova_table_del(phys_addr_t paddr, size_t len __rte_unused) >>> >>> len is not unused. >> >> I will fix this. >> Actually, this function itself is useless - more for symmetry reason. >> Callers would be either simply updating the table, or ignoring it >> completely. But, yes, this is indeed wrong that I set that unused. >> > > Actually, I was wrong in my first reply. In case of > dpaax_iova_table_del(), len is indeed redundant. This is because the > mapping is for a complete page (min of 2MB size), even if the request is > for lesser length. So, removal of a single entry (of fixed size) would > be done. > > In fact, while on this, I think deleting a PA->VA entry itself is > incorrect (not just useless). A single entry (~2MB equivalent) can > represent multiple users (working on a rte_malloc'd area, for example). > So, effectively, its always an update - not an add or del. I'm not sure what you mean here. If you got a mem event about memory area being freed, it's guaranteed to *not* have any users - neither malloc, nor any other memory. And len is always page-aligned. > > I will send updated series with this change. > > [...] > > -- Thanks, Anatoly