From patchwork Sun Jun 28 11:12:50 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Song Bao Hua (Barry Song)" X-Patchwork-Id: 11630041 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 351C314E3 for ; Sun, 28 Jun 2020 11:20:02 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 0049B20B80 for ; Sun, 28 Jun 2020 11:20:01 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="v+lRu+ZK" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 0049B20B80 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=hisilicon.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To:Message-ID:Date: Subject:To:From:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=ZwmPcujv6hFQP6yTyFJpjJFxoSsIhCQUoRYXatl4uDw=; b=v+lRu+ZKpDxhQZRHg5cHyKNap yzZ2Bawm6LCr1WP/LrrgY2wbS2y6S5eQGWnYtevcZ6anITtgjaASppSna/5CZyl47QgxZt94RsDz5 2APyiol2MAJQTKvYEdGyjaA1ZWZy7TiZUj4ygPjh698I7fTETyKMlK2+GC1YaAKEUUe0Umtflx59r vXC/FzxeaaANPqB5JmY7YhRjV3godPnvbryLdp+Xrj3a8GLLXgI+6G+b0IRCNegW7S3wkQoghHZnC gu5DIiexw3pv0F3UrXD960ZXlYN2FttyY10p8XFOWk9fny17UHIIoVImiuzjZ8m6JXosthZdxrUEP v9203XDMg==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1jpVHC-0004h9-1b; Sun, 28 Jun 2020 11:15:10 +0000 Received: from szxga06-in.huawei.com ([45.249.212.32] helo=huawei.com) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1jpVH6-0004fU-TM for linux-arm-kernel@lists.infradead.org; Sun, 28 Jun 2020 11:15:06 +0000 Received: from DGGEMS412-HUB.china.huawei.com (unknown [172.30.72.60]) by Forcepoint Email with ESMTP id AF7234EC6771B2A72DB5; Sun, 28 Jun 2020 19:14:53 +0800 (CST) Received: from SWX921481.china.huawei.com (10.126.201.68) by DGGEMS412-HUB.china.huawei.com (10.3.19.212) with Microsoft SMTP Server id 14.3.487.0; Sun, 28 Jun 2020 19:14:43 +0800 From: Barry Song To: , , , , , Subject: [PATCH v3 1/2] dma-direct: provide the ability to reserve per-numa CMA Date: Sun, 28 Jun 2020 23:12:50 +1200 Message-ID: <20200628111251.19108-2-song.bao.hua@hisilicon.com> X-Mailer: git-send-email 2.21.0.windows.1 In-Reply-To: <20200628111251.19108-1-song.bao.hua@hisilicon.com> References: <20200628111251.19108-1-song.bao.hua@hisilicon.com> MIME-Version: 1.0 X-Originating-IP: [10.126.201.68] X-CFilter-Loop: Reflected X-Spam-Note: CRM114 invocation failed X-Spam-Score: -2.3 (--) X-Spam-Report: SpamAssassin version 3.4.4 on merlin.infradead.org summary: Content analysis details: (-2.3 points) pts rule name description ---- ---------------------- -------------------------------------------------- -2.3 RCVD_IN_DNSWL_MED RBL: Sender listed at https://www.dnswl.org/, medium trust [45.249.212.32 listed in list.dnswl.org] -0.0 RCVD_IN_MSPIKE_H4 RBL: Very Good reputation (+4) [45.249.212.32 listed in wl.mailspike.net] -0.0 SPF_PASS SPF: sender matches SPF record -0.0 SPF_HELO_PASS SPF: HELO matches SPF record -0.0 RCVD_IN_MSPIKE_WL Mailspike good senders X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Barry Song , Steve Capper , linuxarm@huawei.com, linux-kernel@vger.kernel.org, iommu@lists.linux-foundation.org, Nicolas Saenz Julienne , Jonathan Cameron , Andrew Morton , Mike Rapoport , linux-arm-kernel@lists.infradead.org Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org This is useful for at least two scenarios: 1. ARM64 smmu will get memory from local numa node, it can save its command queues and page tables locally. Tests show it can decrease dma_unmap latency at lot. For example, without this patch, smmu on node2 will get memory from node0 by calling dma_alloc_coherent(), typically, it has to wait for more than 560ns for the completion of CMD_SYNC in an empty command queue; with this patch, it needs 240ns only. 2. when we set iommu passthrough, drivers will get memory from CMA, local memory means much less latency. Cc: Jonathan Cameron Cc: Christoph Hellwig Cc: Marek Szyprowski Cc: Will Deacon Cc: Robin Murphy Cc: Ganapatrao Kulkarni Cc: Catalin Marinas Cc: Nicolas Saenz Julienne Cc: Steve Capper Cc: Andrew Morton Cc: Mike Rapoport Signed-off-by: Barry Song Signed-off-by: Christoph Hellwig --- -v3: * move to use page_to_nid() while freeing cma with respect to Robin's comment, but this will only work after applying my below patch: "mm/cma.c: use exact_nid true to fix possible per-numa cma leak" https://marc.info/?l=linux-mm&m=159333034726647&w=2 * handle the case count <= 1 more properly according to Robin's comment; * add pernuma_cma parameter to support dynamic setting of per-numa cma size; ideally we can leverage the CMA_SIZE_MBYTES, CMA_SIZE_PERCENTAGE and "cma=" kernel parameter and avoid a new paramter separately for per- numa cma. Practically, it is really too complicated considering the below problems: (1) if we leverage the size of default numa for per-numa, we have to avoid creating two cma with same size in node0 since default cma is probably on node0. (2) default cma can consider the address limitation for old devices while per-numa cma doesn't support GFP_DMA and GFP_DMA32. all allocations with limitation flags will fallback to default one. (3) hard to apply CMA_SIZE_PERCENTAGE to per-numa. it is hard to decide if the percentage should apply to the whole memory size or only apply to the memory size of a specific numa node. (4) default cma size has CMA_SIZE_SEL_MIN and CMA_SIZE_SEL_MAX, it makes things even more complicated to per-numa cma. I haven't figured out a good way to leverage the size of default cma for per-numa cma. it seems a separate parameter for per-numa could make life easier. .../admin-guide/kernel-parameters.txt | 9 ++ include/linux/dma-contiguous.h | 4 + kernel/dma/Kconfig | 10 ++ kernel/dma/contiguous.c | 98 +++++++++++++++++-- 4 files changed, 112 insertions(+), 9 deletions(-) diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index fb95fad81c79..c52c22fa6de6 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -599,6 +599,15 @@ altogether. For more information, see include/linux/dma-contiguous.h + pernuma_cma=nn[MG]@[start[MG][-end[MG]]] + [ARM,X86,KNL] + Sets the size of kernel per-numa memory area for + contiguous memory allocations. A value of 0 disables + per-numa CMA altogether. DMA users on node nid will + first try to allocate buffer from the pernuma area + which is located in node nid, if the allocation fails, + they will fallback to the global default memory area. + cmo_free_hint= [PPC] Format: { yes | no } Specify whether pages are marked as being inactive when they are freed. This is used in CMO environments diff --git a/include/linux/dma-contiguous.h b/include/linux/dma-contiguous.h index 03f8e98e3bcc..278a80a40456 100644 --- a/include/linux/dma-contiguous.h +++ b/include/linux/dma-contiguous.h @@ -79,6 +79,8 @@ static inline void dma_contiguous_set_default(struct cma *cma) void dma_contiguous_reserve(phys_addr_t addr_limit); +void dma_pernuma_cma_reserve(void); + int __init dma_contiguous_reserve_area(phys_addr_t size, phys_addr_t base, phys_addr_t limit, struct cma **res_cma, bool fixed); @@ -128,6 +130,8 @@ static inline void dma_contiguous_set_default(struct cma *cma) { } static inline void dma_contiguous_reserve(phys_addr_t limit) { } +static inline void dma_pernuma_cma_reserve(void) { } + static inline int dma_contiguous_reserve_area(phys_addr_t size, phys_addr_t base, phys_addr_t limit, struct cma **res_cma, bool fixed) diff --git a/kernel/dma/Kconfig b/kernel/dma/Kconfig index d006668c0027..aeb976b1d21c 100644 --- a/kernel/dma/Kconfig +++ b/kernel/dma/Kconfig @@ -104,6 +104,16 @@ config DMA_CMA if DMA_CMA comment "Default contiguous memory area size:" +config CMA_PERNUMA_SIZE_MBYTES + int "Size in Mega Bytes for per-numa CMA areas" + depends on NUMA + default 16 if ARM64 + default 0 + help + Defines the size (in MiB) of the per-numa memory area for Contiguous + Memory Allocator. Every numa node will get a separate CMA with this + size. If the size of 0 is selected, per-numa CMA is disabled. + config CMA_SIZE_MBYTES int "Size in Mega Bytes" depends on !CMA_SIZE_SEL_PERCENTAGE diff --git a/kernel/dma/contiguous.c b/kernel/dma/contiguous.c index 15bc5026c485..d0bb694c2f4d 100644 --- a/kernel/dma/contiguous.c +++ b/kernel/dma/contiguous.c @@ -30,7 +30,14 @@ #define CMA_SIZE_MBYTES 0 #endif +#ifdef CONFIG_CMA_PERNUMA_SIZE_MBYTES +#define CMA_SIZE_PERNUMA_MBYTES CONFIG_CMA_PERNUMA_SIZE_MBYTES +#else +#define CMA_SIZE_PERNUMA_MBYTES 0 +#endif + struct cma *dma_contiguous_default_area; +static struct cma *dma_contiguous_pernuma_area[MAX_NUMNODES]; /* * Default global CMA area size can be defined in kernel's .config. @@ -44,6 +51,8 @@ struct cma *dma_contiguous_default_area; */ static const phys_addr_t size_bytes __initconst = (phys_addr_t)CMA_SIZE_MBYTES * SZ_1M; +static phys_addr_t pernuma_size_bytes __initdata = + (phys_addr_t)CMA_SIZE_PERNUMA_MBYTES * SZ_1M; static phys_addr_t size_cmdline __initdata = -1; static phys_addr_t base_cmdline __initdata; static phys_addr_t limit_cmdline __initdata; @@ -69,6 +78,13 @@ static int __init early_cma(char *p) } early_param("cma", early_cma); +static int __init early_pernuma_cma(char *p) +{ + pernuma_size_bytes = memparse(p, &p); + return 0; +} +early_param("pernuma_cma", early_pernuma_cma); + #ifdef CONFIG_CMA_SIZE_PERCENTAGE static phys_addr_t __init __maybe_unused cma_early_percent_memory(void) @@ -96,6 +112,33 @@ static inline __maybe_unused phys_addr_t cma_early_percent_memory(void) #endif +void __init dma_pernuma_cma_reserve(void) +{ + int nid; + + if (!pernuma_size_bytes || nr_online_nodes <= 1) + return; + + for_each_node_state(nid, N_ONLINE) { + int ret; + char name[20]; + + snprintf(name, sizeof(name), "pernuma%d", nid); + ret = cma_declare_contiguous_nid(0, pernuma_size_bytes, 0, 0, + 0, false, name, + &dma_contiguous_pernuma_area[nid], + nid); + if (ret) { + pr_warn("%s: reservation failed: err %d, node %d", __func__, + ret, nid); + continue; + } + + pr_debug("%s: reserved %llu MiB on node %d\n", __func__, + (unsigned long long)pernuma_size_bytes / SZ_1M, nid); + } +} + /** * dma_contiguous_reserve() - reserve area(s) for contiguous memory handling * @limit: End address of the reserved memory (optional, 0 for any). @@ -222,23 +265,35 @@ bool dma_release_from_contiguous(struct device *dev, struct page *pages, * @gfp: Allocation flags. * * This function allocates contiguous memory buffer for specified device. It - * tries to use device specific contiguous memory area if available, or the - * default global one. + * tries to use device specific contiguous memory area if available, or it + * tries to use per-numa cma, if the allocation fails, it will fallback to + * try default global one. * - * Note that it byapss one-page size of allocations from the global area as - * the addresses within one page are always contiguous, so there is no need - * to waste CMA pages for that kind; it also helps reduce fragmentations. + * Note that it bypass one-page size of allocations from the per-numa and + * global area as the addresses within one page are always contiguous, so + * there is no need to waste CMA pages for that kind; it also helps reduce + * fragmentations. */ struct page *dma_alloc_contiguous(struct device *dev, size_t size, gfp_t gfp) { size_t count = size >> PAGE_SHIFT; struct page *page = NULL; struct cma *cma = NULL; + int nid = dev ? dev_to_node(dev) : NUMA_NO_NODE; + bool alloc_from_pernuma = false; + + if ((count <= 1) && !(dev && dev->cma_area)) + return NULL; if (dev && dev->cma_area) cma = dev->cma_area; - else if (count > 1) + else if ((nid != NUMA_NO_NODE) && dma_contiguous_pernuma_area[nid] + && !(gfp & (GFP_DMA | GFP_DMA32))) { + cma = dma_contiguous_pernuma_area[nid]; + alloc_from_pernuma = true; + } else { cma = dma_contiguous_default_area; + } /* CMA can be used only in the context which permits sleeping */ if (cma && gfpflags_allow_blocking(gfp)) { @@ -246,6 +301,11 @@ struct page *dma_alloc_contiguous(struct device *dev, size_t size, gfp_t gfp) size_t cma_align = min_t(size_t, align, CONFIG_CMA_ALIGNMENT); page = cma_alloc(cma, count, cma_align, gfp & __GFP_NOWARN); + + /* fall back to default cma if failed in per-numa cma */ + if (!page && alloc_from_pernuma) + page = cma_alloc(dma_contiguous_default_area, count, + cma_align, gfp & __GFP_NOWARN); } return page; @@ -264,9 +324,29 @@ struct page *dma_alloc_contiguous(struct device *dev, size_t size, gfp_t gfp) */ void dma_free_contiguous(struct device *dev, struct page *page, size_t size) { - if (!cma_release(dev_get_cma_area(dev), page, - PAGE_ALIGN(size) >> PAGE_SHIFT)) - __free_pages(page, get_order(size)); + /* if dev has its own cma, free page from there */ + if (dev && dev->cma_area) { + if (cma_release(dev->cma_area, page, PAGE_ALIGN(size) >> PAGE_SHIFT)) + return; + } else { + /* + * otherwise, page is from either per-numa cma or default cma + */ + int nid = page_to_nid(page); + + if (nid != NUMA_NO_NODE) { + if (cma_release(dma_contiguous_pernuma_area[nid], page, + PAGE_ALIGN(size) >> PAGE_SHIFT)) + return; + } + + if (cma_release(dma_contiguous_default_area, page, + PAGE_ALIGN(size) >> PAGE_SHIFT)) + return; + } + + /* not in any cma, free from buddy */ + __free_pages(page, get_order(size)); } /*