From patchwork Tue Jan 12 17:39:21 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Nithin Dabilpuram X-Patchwork-Id: 86431 X-Patchwork-Delegate: david.marchand@redhat.com Return-Path: X-Original-To: patchwork@inbox.dpdk.org Delivered-To: patchwork@inbox.dpdk.org Received: from mails.dpdk.org (mails.dpdk.org [217.70.189.124]) by inbox.dpdk.org (Postfix) with ESMTP id A0C97A04B5; Tue, 12 Jan 2021 18:39:46 +0100 (CET) Received: from [217.70.189.124] (localhost [127.0.0.1]) by mails.dpdk.org (Postfix) with ESMTP id 509C6140F14; Tue, 12 Jan 2021 18:39:43 +0100 (CET) Received: from mx0b-0016f401.pphosted.com (mx0a-0016f401.pphosted.com [67.231.148.174]) by mails.dpdk.org (Postfix) with ESMTP id 49C3A140F12; Tue, 12 Jan 2021 18:39:41 +0100 (CET) Received: from pps.filterd (m0045849.ppops.net [127.0.0.1]) by mx0a-0016f401.pphosted.com (8.16.0.43/8.16.0.43) with SMTP id 10CHZktZ003547; Tue, 12 Jan 2021 09:39:40 -0800 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=marvell.com; h=from : to : cc : subject : date : message-id : in-reply-to : references : mime-version : content-type; s=pfpt0220; bh=ZDljhYSTmb8u017DksyaXrKC7pXIqAR6/8O3nF4LRSY=; b=eMoeg88Rd6DT5Q5D3/V1L+zko2V0cKza5SmY8d0E5QqVR2U+putbdE8VkpdrEtblH5Yq tOJOoq/JUfK4C3uKHqC7jUktRz08tW/8IVa6u1sxzg5RGntgakjqSWhaxa7c2bIkwimd LdfGsZOZ1X7J31m6igoZ3Re3DpPd7Kk/7imh/sA7eFxKJKdFderCZaGXsivlWQaes4eJ jGJctYNQps/jlr2qOv0fMHBYKfZLe0VyKGcgkVgeek8B9Ug3MfpL2sX7hDk3InkzhtrC oZA0OsOOw4aggBU9lkCn8S/EdcZMHUCxT94a9bbpvP8Eoq1XN0lxTUMxtvk1qgsUHP+U lQ== Received: from dc5-exch01.marvell.com ([199.233.59.181]) by mx0a-0016f401.pphosted.com with ESMTP id 35yaqss255-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-SHA384 bits=256 verify=NOT); Tue, 12 Jan 2021 09:39:40 -0800 Received: from DC5-EXCH01.marvell.com (10.69.176.38) by DC5-EXCH01.marvell.com (10.69.176.38) with Microsoft SMTP Server (TLS) id 15.0.1497.2; Tue, 12 Jan 2021 09:39:39 -0800 Received: from maili.marvell.com (10.69.176.80) by DC5-EXCH01.marvell.com (10.69.176.38) with Microsoft SMTP Server id 15.0.1497.2 via Frontend Transport; Tue, 12 Jan 2021 09:39:39 -0800 Received: from hyd1588t430.marvell.com (unknown [10.29.52.204]) by maili.marvell.com (Postfix) with ESMTP id AEADF3F7041; Tue, 12 Jan 2021 09:39:36 -0800 (PST) From: Nithin Dabilpuram To: , David Christensen , CC: , , Nithin Dabilpuram , Date: Tue, 12 Jan 2021 23:09:21 +0530 Message-ID: <20210112173923.30320-2-ndabilpuram@marvell.com> X-Mailer: git-send-email 2.8.4 In-Reply-To: <20210112173923.30320-1-ndabilpuram@marvell.com> References: <20201012081106.10610-1-ndabilpuram@marvell.com> <20210112173923.30320-1-ndabilpuram@marvell.com> MIME-Version: 1.0 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.343, 18.0.737 definitions=2021-01-12_12:2021-01-12, 2021-01-12 signatures=0 Subject: [dpdk-dev] [PATCH v7 1/3] vfio: revert changes for map contiguous areas in one go X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.29 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" In order to save DMA entries limited by kernel both for externel memory and hugepage memory, an attempt was made to map physically contiguous memory in one go. This cannot be done as VFIO IOMMU type1 does not support partially unmapping a previously mapped memory region while Heap can request for multi page mapping and partial unmapping. Hence for going back to old method of mapping/unmapping at memseg granularity, this commit reverts commit d1c7c0cdf7ba ("vfio: map contiguous areas in one go") Also add documentation on what module parameter needs to be used to increase the per-container dma map limit for VFIO. Fixes: d1c7c0cdf7ba ("vfio: map contiguous areas in one go") Cc: anatoly.burakov@intel.com Cc: stable@dpdk.org Signed-off-by: Nithin Dabilpuram Acked-by: Anatoly Burakov Acked-by: David Christensen --- doc/guides/linux_gsg/linux_drivers.rst | 10 ++++++ lib/librte_eal/linux/eal_vfio.c | 59 +++++----------------------------- 2 files changed, 18 insertions(+), 51 deletions(-) diff --git a/doc/guides/linux_gsg/linux_drivers.rst b/doc/guides/linux_gsg/linux_drivers.rst index 90635a4..9a662a7 100644 --- a/doc/guides/linux_gsg/linux_drivers.rst +++ b/doc/guides/linux_gsg/linux_drivers.rst @@ -25,6 +25,16 @@ To make use of VFIO, the ``vfio-pci`` module must be loaded: VFIO kernel is usually present by default in all distributions, however please consult your distributions documentation to make sure that is the case. +For DMA mapping of either external memory or hugepages, VFIO interface is used. +VFIO does not support partial unmap of once mapped memory. Hence DPDK's memory is +mapped in hugepage granularity or system page granularity. Number of DMA +mappings is limited by kernel with user locked memory limit of a process(rlimit) +for system/hugepage memory. Another per-container overall limit applicable both +for external memory and system memory was added in kernel 5.1 defined by +VFIO module parameter ``dma_entry_limit`` with a default value of 64K. +When application is out of DMA entries, these limits need to be adjusted to +increase the allowed limit. + Since Linux version 5.7, the ``vfio-pci`` module supports the creation of virtual functions. After the PF is bound to ``vfio-pci`` module, diff --git a/lib/librte_eal/linux/eal_vfio.c b/lib/librte_eal/linux/eal_vfio.c index 0500824..64b134d 100644 --- a/lib/librte_eal/linux/eal_vfio.c +++ b/lib/librte_eal/linux/eal_vfio.c @@ -517,11 +517,9 @@ static void vfio_mem_event_callback(enum rte_mem_event type, const void *addr, size_t len, void *arg __rte_unused) { - rte_iova_t iova_start, iova_expected; struct rte_memseg_list *msl; struct rte_memseg *ms; size_t cur_len = 0; - uint64_t va_start; msl = rte_mem_virt2memseg_list(addr); @@ -539,63 +537,22 @@ vfio_mem_event_callback(enum rte_mem_event type, const void *addr, size_t len, /* memsegs are contiguous in memory */ ms = rte_mem_virt2memseg(addr, msl); - - /* - * This memory is not guaranteed to be contiguous, but it still could - * be, or it could have some small contiguous chunks. Since the number - * of VFIO mappings is limited, and VFIO appears to not concatenate - * adjacent mappings, we have to do this ourselves. - * - * So, find contiguous chunks, then map them. - */ - va_start = ms->addr_64; - iova_start = iova_expected = ms->iova; while (cur_len < len) { - bool new_contig_area = ms->iova != iova_expected; - bool last_seg = (len - cur_len) == ms->len; - bool skip_last = false; - - /* only do mappings when current contiguous area ends */ - if (new_contig_area) { - if (type == RTE_MEM_EVENT_ALLOC) - vfio_dma_mem_map(default_vfio_cfg, va_start, - iova_start, - iova_expected - iova_start, 1); - else - vfio_dma_mem_map(default_vfio_cfg, va_start, - iova_start, - iova_expected - iova_start, 0); - va_start = ms->addr_64; - iova_start = ms->iova; - } /* some memory segments may have invalid IOVA */ if (ms->iova == RTE_BAD_IOVA) { RTE_LOG(DEBUG, EAL, "Memory segment at %p has bad IOVA, skipping\n", ms->addr); - skip_last = true; + goto next; } - iova_expected = ms->iova + ms->len; + if (type == RTE_MEM_EVENT_ALLOC) + vfio_dma_mem_map(default_vfio_cfg, ms->addr_64, + ms->iova, ms->len, 1); + else + vfio_dma_mem_map(default_vfio_cfg, ms->addr_64, + ms->iova, ms->len, 0); +next: cur_len += ms->len; ++ms; - - /* - * don't count previous segment, and don't attempt to - * dereference a potentially invalid pointer. - */ - if (skip_last && !last_seg) { - iova_expected = iova_start = ms->iova; - va_start = ms->addr_64; - } else if (!skip_last && last_seg) { - /* this is the last segment and we're not skipping */ - if (type == RTE_MEM_EVENT_ALLOC) - vfio_dma_mem_map(default_vfio_cfg, va_start, - iova_start, - iova_expected - iova_start, 1); - else - vfio_dma_mem_map(default_vfio_cfg, va_start, - iova_start, - iova_expected - iova_start, 0); - } } }