From patchwork Tue Sep 26 18:57:28 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Hildenbrand X-Patchwork-Id: 1839907 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@legolas.ozlabs.org Authentication-Results: legolas.ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=redhat.com header.i=@redhat.com header.a=rsa-sha256 header.s=mimecast20190719 header.b=JVgwhgvB; dkim-atps=neutral Authentication-Results: legolas.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=nongnu.org (client-ip=209.51.188.17; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=patchwork.ozlabs.org) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-ECDSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by legolas.ozlabs.org (Postfix) with ESMTPS id 4Rw8Dg56Kzz1ypD for ; Wed, 27 Sep 2023 04:59:31 +1000 (AEST) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1qlDHC-0008EN-Tk; Tue, 26 Sep 2023 14:59:18 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qlDHA-000847-Es for qemu-devel@nongnu.org; Tue, 26 Sep 2023 14:59:16 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qlDH8-00037a-Gm for qemu-devel@nongnu.org; Tue, 26 Sep 2023 14:59:16 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1695754753; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=5slP1Mq6ReelzapelY7FkkpRO49e4JIwaD4dFcmfqHc=; b=JVgwhgvB4CHKFbrMKsapCop2+K7q1Ybqjw9Hske76XYe3QJpOixAnzgJMhDUVoRz5fIuQO HUhuTaWXPJZZvWEQP3HELuD6iOgRtya4MdS1fsWWa8Is43RHmLFGqjh/NkqyTE0DKyxl5N YJgSDhxoEtR8tHpg4MJjadoF79eU4ag= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-179-feTK4n4PNCexBE0aSqjznw-1; Tue, 26 Sep 2023 14:59:10 -0400 X-MC-Unique: feTK4n4PNCexBE0aSqjznw-1 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.rdu2.redhat.com [10.11.54.4]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 828FA8039C1; Tue, 26 Sep 2023 18:59:09 +0000 (UTC) Received: from t14s.fritz.box (unknown [10.39.192.33]) by smtp.corp.redhat.com (Postfix) with ESMTP id 1F2D42026D4B; Tue, 26 Sep 2023 18:59:02 +0000 (UTC) From: David Hildenbrand To: qemu-devel@nongnu.org Cc: David Hildenbrand , Paolo Bonzini , Igor Mammedov , Xiao Guangrong , "Michael S. Tsirkin" , Peter Xu , =?utf-8?q?Philippe_Mathieu-Daud=C3=A9?= , Eduardo Habkost , Marcel Apfelbaum , Yanan Wang , Michal Privoznik , =?utf-8?q?Daniel_P_=2E_Berrang=C3=A9?= , Gavin Shan , Alex Williamson , Stefan Hajnoczi , "Maciej S . Szmigiero" , kvm@vger.kernel.org, "Maciej S . Szmigiero" Subject: [PATCH v4 08/18] memory-device: Track required and actually used memslots in DeviceMemoryState Date: Tue, 26 Sep 2023 20:57:28 +0200 Message-ID: <20230926185738.277351-9-david@redhat.com> In-Reply-To: <20230926185738.277351-1-david@redhat.com> References: <20230926185738.277351-1-david@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.4 Received-SPF: pass client-ip=170.10.129.124; envelope-from=david@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Let's track how many memslots are required by plugged memory devices and how many are currently actually getting used by plugged memory devices. "required - used" is the number of reserved memslots. For now, the number of used and required memslots is always equal, and there are no reservations. This is a preparation for memory devices that want to dynamically consume memslots after initially specifying how many they require -- where we'll end up with reserved memslots. To track the number of used memslots, create a new address space for our device memory and register a memory listener (add/remove) for that address space. Reviewed-by: Maciej S. Szmigiero Signed-off-by: David Hildenbrand --- hw/mem/memory-device.c | 54 ++++++++++++++++++++++++++++++++++++++++++ include/hw/boards.h | 10 +++++++- 2 files changed, 63 insertions(+), 1 deletion(-) diff --git a/hw/mem/memory-device.c b/hw/mem/memory-device.c index 0eec0872a9..d37cfbd65d 100644 --- a/hw/mem/memory-device.c +++ b/hw/mem/memory-device.c @@ -286,6 +286,7 @@ void memory_device_plug(MemoryDeviceState *md, MachineState *ms) g_assert(ms->device_memory); ms->device_memory->used_region_size += memory_region_size(mr); + ms->device_memory->required_memslots += memory_device_get_memslots(md); memory_region_add_subregion(&ms->device_memory->mr, addr - ms->device_memory->base, mr); trace_memory_device_plug(DEVICE(md)->id ? DEVICE(md)->id : "", addr); @@ -305,6 +306,7 @@ void memory_device_unplug(MemoryDeviceState *md, MachineState *ms) memory_region_del_subregion(&ms->device_memory->mr, mr); ms->device_memory->used_region_size -= memory_region_size(mr); + ms->device_memory->required_memslots -= memory_device_get_memslots(md); trace_memory_device_unplug(DEVICE(md)->id ? DEVICE(md)->id : "", mdc->get_addr(md)); } @@ -324,6 +326,50 @@ uint64_t memory_device_get_region_size(const MemoryDeviceState *md, return memory_region_size(mr); } +static void memory_devices_region_mod(MemoryListener *listener, + MemoryRegionSection *mrs, bool add) +{ + DeviceMemoryState *dms = container_of(listener, DeviceMemoryState, + listener); + + if (!memory_region_is_ram(mrs->mr)) { + warn_report("Unexpected memory region mapped into device memory region."); + return; + } + + /* + * The expectation is that each distinct RAM memory region section in + * our region for memory devices consumes exactly one memslot in KVM + * and in vhost. For vhost, this is true, except: + * * ROM memory regions don't consume a memslot. These get used very + * rarely for memory devices (R/O NVDIMMs). + * * Memslots without a fd (memory-backend-ram) don't necessarily + * consume a memslot. Such setups are quite rare and possibly bogus: + * the memory would be inaccessible by such vhost devices. + * + * So for vhost, in corner cases we might over-estimate the number of + * memslots that are currently used or that might still be reserved + * (required - used). + */ + dms->used_memslots += add ? 1 : -1; + + if (dms->used_memslots > dms->required_memslots) { + warn_report("Memory devices use more memory slots than indicated as required."); + } +} + +static void memory_devices_region_add(MemoryListener *listener, + MemoryRegionSection *mrs) +{ + return memory_devices_region_mod(listener, mrs, true); +} + +static void memory_devices_region_del(MemoryListener *listener, + MemoryRegionSection *mrs) +{ + return memory_devices_region_mod(listener, mrs, false); +} + void machine_memory_devices_init(MachineState *ms, hwaddr base, uint64_t size) { g_assert(size); @@ -333,8 +379,16 @@ void machine_memory_devices_init(MachineState *ms, hwaddr base, uint64_t size) memory_region_init(&ms->device_memory->mr, OBJECT(ms), "device-memory", size); + address_space_init(&ms->device_memory->as, &ms->device_memory->mr, + "device-memory"); memory_region_add_subregion(get_system_memory(), ms->device_memory->base, &ms->device_memory->mr); + + /* Track the number of memslots used by memory devices. */ + ms->device_memory->listener.region_add = memory_devices_region_add; + ms->device_memory->listener.region_del = memory_devices_region_del; + memory_listener_register(&ms->device_memory->listener, + &ms->device_memory->as); } static const TypeInfo memory_device_info = { diff --git a/include/hw/boards.h b/include/hw/boards.h index 6c67af196a..5a9d72289c 100644 --- a/include/hw/boards.h +++ b/include/hw/boards.h @@ -296,15 +296,23 @@ struct MachineClass { * DeviceMemoryState: * @base: address in guest physical address space where the memory * address space for memory devices starts - * @mr: address space container for memory devices + * @mr: memory region container for memory devices + * @as: address space for memory devices + * @listener: memory listener used to track used memslots in the address space * @dimm_size: the sum of plugged DIMMs' sizes * @used_region_size: the part of @mr already used by memory devices + * @required_memslots: the number of memslots required by memory devices + * @used_memslots: the number of memslots currently used by memory devices */ typedef struct DeviceMemoryState { hwaddr base; MemoryRegion mr; + AddressSpace as; + MemoryListener listener; uint64_t dimm_size; uint64_t used_region_size; + unsigned int required_memslots; + unsigned int used_memslots; } DeviceMemoryState; /**