From patchwork Wed Sep 23 11:38:56 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Hildenbrand X-Patchwork-Id: 272944 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=-9.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 90134C2D0A8 for ; Wed, 23 Sep 2020 11:44:43 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (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 1282C20663 for ; Wed, 23 Sep 2020 11:44:43 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="ONMItf1M" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 1282C20663 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:56056 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1kL3CU-0004J8-4D for qemu-devel@archiver.kernel.org; Wed, 23 Sep 2020 07:44:42 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:35050) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1kL37H-0008LT-U7 for qemu-devel@nongnu.org; Wed, 23 Sep 2020 07:39:21 -0400 Received: from us-smtp-1.mimecast.com ([205.139.110.61]:25644 helo=us-smtp-delivery-1.mimecast.com) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1kL37C-0006tt-Qo for qemu-devel@nongnu.org; Wed, 23 Sep 2020 07:39:19 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1600861152; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=clGgZC2wlrYw0qQcMPAENuXwJPMUEhiR/ZdvV3W408E=; b=ONMItf1MMK8qhu13zLERMxAhgJwPEuKZ/uDnu8mTh8z9Mxs10DT7A/GauLtGGVEk+T4Que uPw7eaZGmvnKgyWgDHc5IY3z4onQZRazBmmnsHlmFXUqTovwHqAeVzeSG04/u7AMv+N9CS nX3mj3d825NmYhqRo4eX2y1LyUIRL4A= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-442-5WTCmKGaOpK7-V5zXn4Uxg-1; Wed, 23 Sep 2020 07:39:11 -0400 X-MC-Unique: 5WTCmKGaOpK7-V5zXn4Uxg-1 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id D45D11007464; Wed, 23 Sep 2020 11:39:09 +0000 (UTC) Received: from t480s.redhat.com (ovpn-112-54.ams2.redhat.com [10.36.112.54]) by smtp.corp.redhat.com (Postfix) with ESMTP id 8D3BF78816; Wed, 23 Sep 2020 11:39:05 +0000 (UTC) From: David Hildenbrand To: qemu-devel@nongnu.org Subject: [PATCH v1 1/5] virtio-mem: Probe THP size to determine default block size Date: Wed, 23 Sep 2020 13:38:56 +0200 Message-Id: <20200923113900.72718-2-david@redhat.com> In-Reply-To: <20200923113900.72718-1-david@redhat.com> References: <20200923113900.72718-1-david@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=david@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Received-SPF: pass client-ip=205.139.110.61; envelope-from=david@redhat.com; helo=us-smtp-delivery-1.mimecast.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/09/23 03:55:48 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x [generic] [fuzzy] X-Spam_score_int: -32 X-Spam_score: -3.3 X-Spam_bar: --- X-Spam_report: (-3.3 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-1.228, 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_H2=-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: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Pankaj Gupta , "Michael S. Tsirkin" , David Hildenbrand , "Dr . David Alan Gilbert" , Wei Yang , Igor Mammedov Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Let's allow a minimum block size of 1 MiB in all configurations. Use a default block size based on the THP size, and warn if something smaller is configured by the user. VIRTIO_MEM only supports Linux (depends on LINUX), so we can probe the THP size unconditionally. For now we only support virtio-mem on x86-64 - there isn't a user-visiable change (x86-64 only supports 2 MiB THP on the PMD level) - the default was, and will be 2 MiB. If we ever have THP on the PUD level (e.g., 1 GiB THP on x86-64), we expect to have a trigger to explicitly opt-in for the new THP granularity. Cc: "Michael S. Tsirkin" Cc: Wei Yang Cc: Dr. David Alan Gilbert Cc: Igor Mammedov Cc: Pankaj Gupta Signed-off-by: David Hildenbrand Reviewed-by: Pankaj Gupta --- hw/virtio/virtio-mem.c | 82 +++++++++++++++++++++++++++++++++++++++--- 1 file changed, 78 insertions(+), 4 deletions(-) diff --git a/hw/virtio/virtio-mem.c b/hw/virtio/virtio-mem.c index 8fbec77ccc..58098686ee 100644 --- a/hw/virtio/virtio-mem.c +++ b/hw/virtio/virtio-mem.c @@ -33,10 +33,70 @@ #include "trace.h" /* - * Use QEMU_VMALLOC_ALIGN, so no THP will have to be split when unplugging - * memory (e.g., 2MB on x86_64). + * Let's not allow blocks smaller than 1 MiB, for example, to keep the tracking + * bitmap small. */ -#define VIRTIO_MEM_MIN_BLOCK_SIZE ((uint32_t)QEMU_VMALLOC_ALIGN) +#define VIRTIO_MEM_MIN_BLOCK_SIZE ((uint32_t)(1 * MiB)) + +/* + * We want to have a reasonable default block size such that + * 1. We avoid splitting THPs when unplugging memory, which degrades + * performance. + * 2. We avoid placing THPs for plugged blocks that also cover unplugged + * blocks. + * + * The actual THP size might differ between Linux kernels, so we try to probe + * it. In the future (if we ever run into issues regarding 2.), we might want + * to disable THP in case we fail to properly probe the THP size, or if the + * block size is configured smaller than the THP size. + */ +static uint32_t default_block_size; + +#define HPAGE_PMD_SIZE_PATH "/sys/kernel/mm/transparent_hugepage/hpage_pmd_size" +static uint32_t virtio_mem_default_block_size(void) +{ + gchar *content = NULL; + const char *endptr; + uint64_t tmp; + + if (default_block_size) { + return default_block_size; + } + + /* + * Try to probe the actual THP size, fallback to (sane but eventually + * incorrect) default sizes. + */ + if (g_file_get_contents(HPAGE_PMD_SIZE_PATH, &content, NULL, NULL) && + !qemu_strtou64(content, &endptr, 0, &tmp) && + (!endptr || *endptr == '\n')) { + /* + * Sanity-check the value, if it's too big (e.g., aarch64 with 64k base + * pages) or weird, fallback to something smaller. + */ + if (!tmp || !is_power_of_2(tmp) || tmp > 16 * MiB) { + warn_report("Detected a THP size of %" PRIx64 + " MiB, falling back to 1 MiB.", tmp / MiB); + default_block_size = 1 * MiB; + } else { + default_block_size = tmp; + } + } else { +#if defined(__x86_64__) || defined(__arm__) || defined(__aarch64__) || \ + defined(__powerpc64__) + default_block_size = 2 * MiB; +#else + /* fallback to 1 MiB (e.g., the THP size on s390x) */ + default_block_size = 1 * MiB; +#endif + warn_report("Could not detect THP size, falling back to %" PRIx64 + " MiB.", default_block_size / MiB); + } + + g_free(content); + return default_block_size; +} + /* * Size the usable region bigger than the requested size if possible. Esp. * Linux guests will only add (aligned) memory blocks in case they fully @@ -437,6 +497,15 @@ static void virtio_mem_device_realize(DeviceState *dev, Error **errp) rb = vmem->memdev->mr.ram_block; page_size = qemu_ram_pagesize(rb); + /* + * If the block size wasn't configured by the user, use a sane default. This + * allows using hugetlbfs backends with a pagesize bigger than the detected + * THP size without manual intervention/configuration. + */ + if (!vmem->block_size) { + vmem->block_size = MAX(page_size, virtio_mem_default_block_size()); + } + if (vmem->block_size < page_size) { error_setg(errp, "'%s' property has to be at least the page size (0x%" PRIx64 ")", VIRTIO_MEM_BLOCK_SIZE_PROP, page_size); @@ -760,6 +829,12 @@ static void virtio_mem_set_block_size(Object *obj, Visitor *v, const char *name, error_setg(errp, "'%s' property has to be a power of two", name); return; } + + if (value < virtio_mem_default_block_size()) { + warn_report("'%s' property is smaller than the default block size " + "(detected THP size) of %" PRIx64 " MiB", name, + virtio_mem_default_block_size() / MiB); + } vmem->block_size = value; } @@ -810,7 +885,6 @@ static void virtio_mem_instance_init(Object *obj) { VirtIOMEM *vmem = VIRTIO_MEM(obj); - vmem->block_size = VIRTIO_MEM_MIN_BLOCK_SIZE; notifier_list_init(&vmem->size_change_notifiers); vmem->precopy_notifier.notify = virtio_mem_precopy_notify; From patchwork Wed Sep 23 11:38:57 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Hildenbrand X-Patchwork-Id: 304624 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=-9.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 7BA6BC2D0A8 for ; Wed, 23 Sep 2020 11:46:16 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (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 DB1EC214D8 for ; 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Wed, 23 Sep 2020 11:39:11 +0000 (UTC) Received: from t480s.redhat.com (ovpn-112-54.ams2.redhat.com [10.36.112.54]) by smtp.corp.redhat.com (Postfix) with ESMTP id 2D3C678816; Wed, 23 Sep 2020 11:39:10 +0000 (UTC) From: David Hildenbrand To: qemu-devel@nongnu.org Subject: [PATCH v1 2/5] virtio-mem: Check that "memaddr" is multiples of the block size Date: Wed, 23 Sep 2020 13:38:57 +0200 Message-Id: <20200923113900.72718-3-david@redhat.com> In-Reply-To: <20200923113900.72718-1-david@redhat.com> References: <20200923113900.72718-1-david@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=david@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Received-SPF: pass client-ip=216.205.24.124; envelope-from=david@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/09/22 23:02:20 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x [generic] [fuzzy] X-Spam_score_int: -32 X-Spam_score: -3.3 X-Spam_bar: --- X-Spam_report: (-3.3 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-1.228, 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_H5=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: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Pankaj Gupta , "Michael S. Tsirkin" , David Hildenbrand , "Dr . David Alan Gilbert" , Wei Yang , Igor Mammedov Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" The spec requires us to set the "addr" in guest physical address space to multiples of the block size. In some cases, this is not the case right now: For example, when starting a VM with 4 GiB boot memory and a virtio-mem device with a block size of 2 GiB, "memaddr" will be auto-assigned to 0x140000000 / 5 GiB. We'll try to improve auto-assignment for memory devices next, to avoid bailing out in case memory device code selects a bad address. Note: The Linux driver doesn't support such big block sizes yet. Cc: "Michael S. Tsirkin" Cc: Wei Yang Cc: Dr. David Alan Gilbert Cc: Igor Mammedov Cc: Pankaj Gupta Signed-off-by: David Hildenbrand Reviewed-by: Pankaj Gupta --- hw/virtio/virtio-mem.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/hw/virtio/virtio-mem.c b/hw/virtio/virtio-mem.c index 58098686ee..716eddd792 100644 --- a/hw/virtio/virtio-mem.c +++ b/hw/virtio/virtio-mem.c @@ -515,6 +515,11 @@ static void virtio_mem_device_realize(DeviceState *dev, Error **errp) ")", VIRTIO_MEM_REQUESTED_SIZE_PROP, VIRTIO_MEM_BLOCK_SIZE_PROP, vmem->block_size); return; + } else if (!QEMU_IS_ALIGNED(vmem->addr, vmem->block_size)) { + error_setg(errp, "'%s' property has to be multiples of '%s' (0x%" PRIx64 + ")", VIRTIO_MEM_ADDR_PROP, VIRTIO_MEM_BLOCK_SIZE_PROP, + vmem->block_size); + return; } else if (!QEMU_IS_ALIGNED(memory_region_size(&vmem->memdev->mr), vmem->block_size)) { error_setg(errp, "'%s' property memdev size has to be multiples of" From patchwork Wed Sep 23 11:38:58 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Hildenbrand X-Patchwork-Id: 272945 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=-9.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS 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 35059C2D0A8 for ; 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Wed, 23 Sep 2020 07:39:14 -0400 X-MC-Unique: YjO_PiCpP_OUH-SblpHfjw-1 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 79FA3801AB7; Wed, 23 Sep 2020 11:39:13 +0000 (UTC) Received: from t480s.redhat.com (ovpn-112-54.ams2.redhat.com [10.36.112.54]) by smtp.corp.redhat.com (Postfix) with ESMTP id F1928702E7; Wed, 23 Sep 2020 11:39:11 +0000 (UTC) From: David Hildenbrand To: qemu-devel@nongnu.org Subject: [PATCH v1 3/5] memory-device: Support big alignment requirements Date: Wed, 23 Sep 2020 13:38:58 +0200 Message-Id: <20200923113900.72718-4-david@redhat.com> In-Reply-To: <20200923113900.72718-1-david@redhat.com> References: <20200923113900.72718-1-david@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=david@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Received-SPF: pass client-ip=207.211.31.120; envelope-from=david@redhat.com; helo=us-smtp-1.mimecast.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/09/23 07:39:18 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x [generic] [fuzzy] X-Spam_score_int: -32 X-Spam_score: -3.3 X-Spam_bar: --- X-Spam_report: (-3.3 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-1.228, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, 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: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Pankaj Gupta , "Michael S. Tsirkin" , David Hildenbrand , "Dr . David Alan Gilbert" , Wei Yang , Igor Mammedov Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Let's warn instead of bailing out - the worst thing that can happen is that we'll fail hot/coldplug later. The user got warned, and this should be rare. This will be necessary for memory devices with rather big (user-defined) alignment requirements - say a virtio-mem device with a 2G block size - which will become important, for example, when supporting vfio in the future. Cc: "Michael S. Tsirkin" Cc: Wei Yang Cc: Dr. David Alan Gilbert Cc: Igor Mammedov Cc: Pankaj Gupta Signed-off-by: David Hildenbrand Reviewed-by: Pankaj Gupta --- hw/mem/memory-device.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/hw/mem/memory-device.c b/hw/mem/memory-device.c index 4bc9cf0917..8a736f1a26 100644 --- a/hw/mem/memory-device.c +++ b/hw/mem/memory-device.c @@ -119,9 +119,10 @@ static uint64_t memory_device_get_free_addr(MachineState *ms, /* start of address space indicates the maximum alignment we expect */ if (!QEMU_IS_ALIGNED(range_lob(&as), align)) { - error_setg(errp, "the alignment (0x%" PRIx64 ") is not supported", - align); - return 0; + warn_report("the alignment (0x%" PRIx64 ") exceeds the expected" + " maximum alignment, memory will get fragmented and not" + " all 'maxmem' might be usable for memory devices.", + align); } memory_device_check_addable(ms, size, &err); @@ -151,7 +152,7 @@ static uint64_t memory_device_get_free_addr(MachineState *ms, return 0; } } else { - if (range_init(&new, range_lob(&as), size)) { + if (range_init(&new, QEMU_ALIGN_UP(range_lob(&as), align), size)) { error_setg(errp, "can't add memory device, device too big"); return 0; } From patchwork Wed Sep 23 11:38:59 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Hildenbrand X-Patchwork-Id: 304626 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=-9.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 4B10EC2D0A8 for ; Wed, 23 Sep 2020 11:40:58 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (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 D9011214D8 for ; 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Wed, 23 Sep 2020 11:39:15 +0000 (UTC) Received: from t480s.redhat.com (ovpn-112-54.ams2.redhat.com [10.36.112.54]) by smtp.corp.redhat.com (Postfix) with ESMTP id C5516702E7; Wed, 23 Sep 2020 11:39:13 +0000 (UTC) From: David Hildenbrand To: qemu-devel@nongnu.org Subject: [PATCH v1 4/5] memory-device: Add get_min_alignment() callback Date: Wed, 23 Sep 2020 13:38:59 +0200 Message-Id: <20200923113900.72718-5-david@redhat.com> In-Reply-To: <20200923113900.72718-1-david@redhat.com> References: <20200923113900.72718-1-david@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=david@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Received-SPF: pass client-ip=63.128.21.124; envelope-from=david@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/09/23 00:53:58 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x [generic] [fuzzy] X-Spam_score_int: -32 X-Spam_score: -3.3 X-Spam_bar: --- X-Spam_report: (-3.3 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-1.228, 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_H5=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: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Pankaj Gupta , "Michael S. Tsirkin" , David Hildenbrand , "Dr . David Alan Gilbert" , Wei Yang , Igor Mammedov Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Will be used by virtio-mem to express special alignment requirements due to manually configured, big block sizes. This avoids failing later when realizing, because auto-detection wasn't able to assign a properly aligned address. Cc: "Michael S. Tsirkin" Cc: Wei Yang Cc: Dr. David Alan Gilbert Cc: Igor Mammedov Cc: Pankaj Gupta Signed-off-by: David Hildenbrand Reviewed-by: Pankaj Gupta --- hw/mem/memory-device.c | 11 +++++++++-- include/hw/mem/memory-device.h | 11 +++++++++++ 2 files changed, 20 insertions(+), 2 deletions(-) diff --git a/hw/mem/memory-device.c b/hw/mem/memory-device.c index 8a736f1a26..cf0627fd01 100644 --- a/hw/mem/memory-device.c +++ b/hw/mem/memory-device.c @@ -259,7 +259,7 @@ void memory_device_pre_plug(MemoryDeviceState *md, MachineState *ms, { const MemoryDeviceClass *mdc = MEMORY_DEVICE_GET_CLASS(md); Error *local_err = NULL; - uint64_t addr, align; + uint64_t addr, align = 0; MemoryRegion *mr; mr = mdc->get_memory_region(md, &local_err); @@ -267,7 +267,14 @@ void memory_device_pre_plug(MemoryDeviceState *md, MachineState *ms, goto out; } - align = legacy_align ? *legacy_align : memory_region_get_alignment(mr); + if (legacy_align) { + align = *legacy_align; + } else { + if (mdc->get_min_alignment) { + align = mdc->get_min_alignment(md); + } + align = MAX(align, memory_region_get_alignment(mr)); + } addr = mdc->get_addr(md); addr = memory_device_get_free_addr(ms, !addr ? NULL : &addr, align, memory_region_size(mr), &local_err); diff --git a/include/hw/mem/memory-device.h b/include/hw/mem/memory-device.h index cde52e83c9..563893854a 100644 --- a/include/hw/mem/memory-device.h +++ b/include/hw/mem/memory-device.h @@ -88,6 +88,17 @@ struct MemoryDeviceClass { */ MemoryRegion *(*get_memory_region)(MemoryDeviceState *md, Error **errp); + /* + * Optional: Return the desired minimum alignment of the device in guest + * physical address space, ignoring the alignment requirements of the + * memory region (e.g., based on the page size). The final alignment is + * computed by selecting the maximum of both alignments. + * + * Called when plugging the memory device to detect the required alignment + * during address assignment. + */ + uint64_t (*get_min_alignment)(const MemoryDeviceState *md); + /* * Translate the memory device into #MemoryDeviceInfo. */ From patchwork Wed Sep 23 11:39:00 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Hildenbrand X-Patchwork-Id: 304625 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=-9.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 8F338C2D0A8 for ; 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Wed, 23 Sep 2020 07:39:18 -0400 X-MC-Unique: 2kZ7HAhROoG-kBTn7Ma3SQ-1 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 266CE427C4; Wed, 23 Sep 2020 11:39:17 +0000 (UTC) Received: from t480s.redhat.com (ovpn-112-54.ams2.redhat.com [10.36.112.54]) by smtp.corp.redhat.com (Postfix) with ESMTP id 9C712702E7; Wed, 23 Sep 2020 11:39:15 +0000 (UTC) From: David Hildenbrand To: qemu-devel@nongnu.org Subject: [PATCH v1 5/5] virito-mem: Implement get_min_alignment() Date: Wed, 23 Sep 2020 13:39:00 +0200 Message-Id: <20200923113900.72718-6-david@redhat.com> In-Reply-To: <20200923113900.72718-1-david@redhat.com> References: <20200923113900.72718-1-david@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=david@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Received-SPF: pass client-ip=63.128.21.124; envelope-from=david@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/09/23 00:53:58 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x [generic] [fuzzy] X-Spam_score_int: -32 X-Spam_score: -3.3 X-Spam_bar: --- X-Spam_report: (-3.3 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-1.228, 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_H5=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: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Pankaj Gupta , "Michael S. Tsirkin" , David Hildenbrand , "Dr . David Alan Gilbert" , Wei Yang , Igor Mammedov Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" This allows auto-assignment of a properly aligned address in guest physical address space. For example, when specifying a 2GB block size for a virtio-mem device with 10GB with a memory setup "-m 4G, 20G", we'll no longer fail when realizing. Cc: "Michael S. Tsirkin" Cc: Wei Yang Cc: Dr. David Alan Gilbert Cc: Igor Mammedov Cc: Pankaj Gupta Signed-off-by: David Hildenbrand Reviewed-by: Pankaj Gupta --- hw/virtio/virtio-mem-pci.c | 14 ++++++++++++++ hw/virtio/virtio-mem.c | 8 ++++++++ 2 files changed, 22 insertions(+) diff --git a/hw/virtio/virtio-mem-pci.c b/hw/virtio/virtio-mem-pci.c index 590cec041b..2bfa2474fb 100644 --- a/hw/virtio/virtio-mem-pci.c +++ b/hw/virtio/virtio-mem-pci.c @@ -75,6 +75,19 @@ static void virtio_mem_pci_fill_device_info(const MemoryDeviceState *md, info->type = MEMORY_DEVICE_INFO_KIND_VIRTIO_MEM; } +static uint64_t virtio_mem_pci_get_min_alignment(const MemoryDeviceState *md) +{ + /* + * If no block size was configured, returns the default block size. + * Before the device was realized, this might be smaller than the + * final block size (because it ignores the page size of the memory region). + * However, the alignment of the memory region properly considers the + * page size of the memory region. + */ + return object_property_get_uint(OBJECT(md), VIRTIO_MEM_BLOCK_SIZE_PROP, + &error_abort); +} + static void virtio_mem_pci_size_change_notify(Notifier *notifier, void *data) { VirtIOMEMPCI *pci_mem = container_of(notifier, VirtIOMEMPCI, @@ -109,6 +122,7 @@ static void virtio_mem_pci_class_init(ObjectClass *klass, void *data) mdc->get_plugged_size = virtio_mem_pci_get_plugged_size; mdc->get_memory_region = virtio_mem_pci_get_memory_region; mdc->fill_device_info = virtio_mem_pci_fill_device_info; + mdc->get_min_alignment = virtio_mem_pci_get_min_alignment; } static void virtio_mem_pci_instance_init(Object *obj) diff --git a/hw/virtio/virtio-mem.c b/hw/virtio/virtio-mem.c index 716eddd792..d8222153cf 100644 --- a/hw/virtio/virtio-mem.c +++ b/hw/virtio/virtio-mem.c @@ -805,6 +805,14 @@ static void virtio_mem_get_block_size(Object *obj, Visitor *v, const char *name, const VirtIOMEM *vmem = VIRTIO_MEM(obj); uint64_t value = vmem->block_size; + /* + * If not configured by the user (and we're not realized yet), use the + * default block size. + */ + if (!value) { + value = virtio_mem_default_block_size(); + } + visit_type_size(v, name, &value, errp); }