From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED, USER_AGENT_MUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9512FECE564 for ; Tue, 18 Sep 2018 20:35:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3AAB02133F for ; Tue, 18 Sep 2018 20:35:43 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 3AAB02133F Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730478AbeISCJ5 (ORCPT ); Tue, 18 Sep 2018 22:09:57 -0400 Received: from mx1.redhat.com ([209.132.183.28]:38426 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729873AbeISCJ5 (ORCPT ); Tue, 18 Sep 2018 22:09:57 -0400 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id C44A8C05D3E4; Tue, 18 Sep 2018 20:35:40 +0000 (UTC) Received: from redhat.com (ovpn-124-13.rdu2.redhat.com [10.10.124.13]) by smtp.corp.redhat.com (Postfix) with ESMTPS id A191A805E3; Tue, 18 Sep 2018 20:35:39 +0000 (UTC) Date: Tue, 18 Sep 2018 16:35:37 -0400 From: Jerome Glisse To: Dan Williams Cc: akpm@linux-foundation.org, Christoph Hellwig , Logan Gunthorpe , alexander.h.duyck@intel.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v5 6/7] mm, hmm: Replace hmm_devmem_pages_create() with devm_memremap_pages() Message-ID: <20180918203537.GF14689@redhat.com> References: <153680531988.453305.8080706591516037706.stgit@dwillia2-desk3.amr.corp.intel.com> <153680535314.453305.11205770267271657025.stgit@dwillia2-desk3.amr.corp.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <153680535314.453305.11205770267271657025.stgit@dwillia2-desk3.amr.corp.intel.com> User-Agent: Mutt/1.10.1 (2018-07-13) X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.32]); Tue, 18 Sep 2018 20:35:40 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Sep 12, 2018 at 07:22:33PM -0700, Dan Williams wrote: > Commit e8d513483300 "memremap: change devm_memremap_pages interface to > use struct dev_pagemap" refactored devm_memremap_pages() to allow a > dev_pagemap instance to be supplied. Passing in a dev_pagemap interface > simplifies the design of pgmap type drivers in that they can rely on > container_of() to lookup any private data associated with the given > dev_pagemap instance. > > In addition to the cleanups this also gives hmm users multi-order-radix > improvements that arrived with commit ab1b597ee0e4 "mm, > devm_memremap_pages: use multi-order radix for ZONE_DEVICE lookups" > > As part of the conversion to the devm_memremap_pages() method of > handling the percpu_ref relative to when pages are put, the percpu_ref > completion needs to move to hmm_devmem_ref_exit(). See commit > 71389703839e ("mm, zone_device: Replace {get, put}_zone_device_page...") > for details. > > Reviewed-by: Christoph Hellwig Reviewed-by: Jérôme Glisse > Cc: Logan Gunthorpe > Signed-off-by: Dan Williams > --- > mm/hmm.c | 194 ++++++++------------------------------------------------------ > 1 file changed, 26 insertions(+), 168 deletions(-) > > diff --git a/mm/hmm.c b/mm/hmm.c > index ec1d9eccf176..c6cab5205b99 100644 > --- a/mm/hmm.c > +++ b/mm/hmm.c > @@ -938,17 +938,16 @@ static void hmm_devmem_ref_exit(void *data) > struct hmm_devmem *devmem; > > devmem = container_of(ref, struct hmm_devmem, ref); > + wait_for_completion(&devmem->completion); > percpu_ref_exit(ref); > } > > -static void hmm_devmem_ref_kill(void *data) > +static void hmm_devmem_ref_kill(struct percpu_ref *ref) > { > - struct percpu_ref *ref = data; > struct hmm_devmem *devmem; > > devmem = container_of(ref, struct hmm_devmem, ref); > percpu_ref_kill(ref); > - wait_for_completion(&devmem->completion); > } > > static int hmm_devmem_fault(struct vm_area_struct *vma, > @@ -971,152 +970,6 @@ static void hmm_devmem_free(struct page *page, void *data) > devmem->ops->free(devmem, page); > } > > -static DEFINE_MUTEX(hmm_devmem_lock); > -static RADIX_TREE(hmm_devmem_radix, GFP_KERNEL); > - > -static void hmm_devmem_radix_release(struct resource *resource) > -{ > - resource_size_t key; > - > - mutex_lock(&hmm_devmem_lock); > - for (key = resource->start; > - key <= resource->end; > - key += PA_SECTION_SIZE) > - radix_tree_delete(&hmm_devmem_radix, key >> PA_SECTION_SHIFT); > - mutex_unlock(&hmm_devmem_lock); > -} > - > -static void hmm_devmem_release(void *data) > -{ > - struct hmm_devmem *devmem = data; > - struct resource *resource = devmem->resource; > - unsigned long start_pfn, npages; > - struct zone *zone; > - struct page *page; > - > - /* pages are dead and unused, undo the arch mapping */ > - start_pfn = (resource->start & ~(PA_SECTION_SIZE - 1)) >> PAGE_SHIFT; > - npages = ALIGN(resource_size(resource), PA_SECTION_SIZE) >> PAGE_SHIFT; > - > - page = pfn_to_page(start_pfn); > - zone = page_zone(page); > - > - mem_hotplug_begin(); > - if (resource->desc == IORES_DESC_DEVICE_PRIVATE_MEMORY) > - __remove_pages(zone, start_pfn, npages, NULL); > - else > - arch_remove_memory(start_pfn << PAGE_SHIFT, > - npages << PAGE_SHIFT, NULL); > - mem_hotplug_done(); > - > - hmm_devmem_radix_release(resource); > -} > - > -static int hmm_devmem_pages_create(struct hmm_devmem *devmem) > -{ > - resource_size_t key, align_start, align_size, align_end; > - struct device *device = devmem->device; > - int ret, nid, is_ram; > - unsigned long pfn; > - > - align_start = devmem->resource->start & ~(PA_SECTION_SIZE - 1); > - align_size = ALIGN(devmem->resource->start + > - resource_size(devmem->resource), > - PA_SECTION_SIZE) - align_start; > - > - is_ram = region_intersects(align_start, align_size, > - IORESOURCE_SYSTEM_RAM, > - IORES_DESC_NONE); > - if (is_ram == REGION_MIXED) { > - WARN_ONCE(1, "%s attempted on mixed region %pr\n", > - __func__, devmem->resource); > - return -ENXIO; > - } > - if (is_ram == REGION_INTERSECTS) > - return -ENXIO; > - > - if (devmem->resource->desc == IORES_DESC_DEVICE_PUBLIC_MEMORY) > - devmem->pagemap.type = MEMORY_DEVICE_PUBLIC; > - else > - devmem->pagemap.type = MEMORY_DEVICE_PRIVATE; > - > - devmem->pagemap.res = *devmem->resource; > - devmem->pagemap.page_fault = hmm_devmem_fault; > - devmem->pagemap.page_free = hmm_devmem_free; > - devmem->pagemap.dev = devmem->device; > - devmem->pagemap.ref = &devmem->ref; > - devmem->pagemap.data = devmem; > - > - mutex_lock(&hmm_devmem_lock); > - align_end = align_start + align_size - 1; > - for (key = align_start; key <= align_end; key += PA_SECTION_SIZE) { > - struct hmm_devmem *dup; > - > - dup = radix_tree_lookup(&hmm_devmem_radix, > - key >> PA_SECTION_SHIFT); > - if (dup) { > - dev_err(device, "%s: collides with mapping for %s\n", > - __func__, dev_name(dup->device)); > - mutex_unlock(&hmm_devmem_lock); > - ret = -EBUSY; > - goto error; > - } > - ret = radix_tree_insert(&hmm_devmem_radix, > - key >> PA_SECTION_SHIFT, > - devmem); > - if (ret) { > - dev_err(device, "%s: failed: %d\n", __func__, ret); > - mutex_unlock(&hmm_devmem_lock); > - goto error_radix; > - } > - } > - mutex_unlock(&hmm_devmem_lock); > - > - nid = dev_to_node(device); > - if (nid < 0) > - nid = numa_mem_id(); > - > - mem_hotplug_begin(); > - /* > - * For device private memory we call add_pages() as we only need to > - * allocate and initialize struct page for the device memory. More- > - * over the device memory is un-accessible thus we do not want to > - * create a linear mapping for the memory like arch_add_memory() > - * would do. > - * > - * For device public memory, which is accesible by the CPU, we do > - * want the linear mapping and thus use arch_add_memory(). > - */ > - if (devmem->pagemap.type == MEMORY_DEVICE_PUBLIC) > - ret = arch_add_memory(nid, align_start, align_size, NULL, > - false); > - else > - ret = add_pages(nid, align_start >> PAGE_SHIFT, > - align_size >> PAGE_SHIFT, NULL, false); > - if (ret) { > - mem_hotplug_done(); > - goto error_add_memory; > - } > - move_pfn_range_to_zone(&NODE_DATA(nid)->node_zones[ZONE_DEVICE], > - align_start >> PAGE_SHIFT, > - align_size >> PAGE_SHIFT, NULL); > - mem_hotplug_done(); > - > - for (pfn = devmem->pfn_first; pfn < devmem->pfn_last; pfn++) { > - struct page *page = pfn_to_page(pfn); > - > - page->pgmap = &devmem->pagemap; > - } > - return 0; > - > -error_add_memory: > - untrack_pfn(NULL, PHYS_PFN(align_start), align_size); > -error_radix: > - hmm_devmem_radix_release(devmem->resource); > -error: > - return ret; > -} > - > /* > * hmm_devmem_add() - hotplug ZONE_DEVICE memory for device memory > * > @@ -1140,6 +993,7 @@ struct hmm_devmem *hmm_devmem_add(const struct hmm_devmem_ops *ops, > { > struct hmm_devmem *devmem; > resource_size_t addr; > + void *result; > int ret; > > dev_pagemap_get_ops(); > @@ -1194,14 +1048,18 @@ struct hmm_devmem *hmm_devmem_add(const struct hmm_devmem_ops *ops, > devmem->pfn_last = devmem->pfn_first + > (resource_size(devmem->resource) >> PAGE_SHIFT); > > - ret = hmm_devmem_pages_create(devmem); > - if (ret) > - return ERR_PTR(ret); > - > - ret = devm_add_action_or_reset(device, hmm_devmem_release, devmem); > - if (ret) > - return ERR_PTR(ret); > + devmem->pagemap.type = MEMORY_DEVICE_PRIVATE; > + devmem->pagemap.res = *devmem->resource; > + devmem->pagemap.page_fault = hmm_devmem_fault; > + devmem->pagemap.page_free = hmm_devmem_free; > + devmem->pagemap.altmap_valid = false; > + devmem->pagemap.ref = &devmem->ref; > + devmem->pagemap.data = devmem; > > + result = devm_memremap_pages(devmem->device, &devmem->pagemap, > + hmm_devmem_ref_kill); > + if (IS_ERR(result)) > + return result; > return devmem; > } > EXPORT_SYMBOL(hmm_devmem_add); > @@ -1211,6 +1069,7 @@ struct hmm_devmem *hmm_devmem_add_resource(const struct hmm_devmem_ops *ops, > struct resource *res) > { > struct hmm_devmem *devmem; > + void *result; > int ret; > > if (res->desc != IORES_DESC_DEVICE_PUBLIC_MEMORY) > @@ -1243,19 +1102,18 @@ struct hmm_devmem *hmm_devmem_add_resource(const struct hmm_devmem_ops *ops, > devmem->pfn_last = devmem->pfn_first + > (resource_size(devmem->resource) >> PAGE_SHIFT); > > - ret = hmm_devmem_pages_create(devmem); > - if (ret) > - return ERR_PTR(ret); > - > - ret = devm_add_action_or_reset(device, hmm_devmem_release, devmem); > - if (ret) > - return ERR_PTR(ret); > - > - ret = devm_add_action_or_reset(device, hmm_devmem_ref_kill, > - &devmem->ref); > - if (ret) > - return ERR_PTR(ret); > + devmem->pagemap.type = MEMORY_DEVICE_PUBLIC; > + devmem->pagemap.res = *devmem->resource; > + devmem->pagemap.page_fault = hmm_devmem_fault; > + devmem->pagemap.page_free = hmm_devmem_free; > + devmem->pagemap.altmap_valid = false; > + devmem->pagemap.ref = &devmem->ref; > + devmem->pagemap.data = devmem; > > + result = devm_memremap_pages(devmem->device, &devmem->pagemap, > + hmm_devmem_ref_kill); > + if (IS_ERR(result)) > + return result; > return devmem; > } > EXPORT_SYMBOL(hmm_devmem_add_resource); >