From nobody Fri May 10 19:07:11 2024 Delivered-To: importer@patchew.org Authentication-Results: mx.zohomail.com; dkim=fail; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=fail(p=none dis=none) header.from=redhat.com Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 1627635322557195.08626546037192; Fri, 30 Jul 2021 01:55:22 -0700 (PDT) Received: from localhost ([::1]:52566 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1m9OIb-0000y0-Im for importer@patchew.org; Fri, 30 Jul 2021 04:55:21 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:42206) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1m9OGp-0006zn-DX for qemu-devel@nongnu.org; Fri, 30 Jul 2021 04:53:32 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:54717) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1m9OGn-00072X-Sk for qemu-devel@nongnu.org; Fri, 30 Jul 2021 04:53:31 -0400 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-586-ote-O2TUNG24X4uEz2EbWQ-1; Fri, 30 Jul 2021 04:53:26 -0400 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 0ACAC92503; Fri, 30 Jul 2021 08:53:25 +0000 (UTC) Received: from t480s.redhat.com (unknown [10.39.194.81]) by smtp.corp.redhat.com (Postfix) with ESMTP id A76A460C05; Fri, 30 Jul 2021 08:53:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1627635209; 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=TBY+mAqGioqKKMSOPOr/xV/Fu/kzVNkYe5+whDj4jKM=; b=TKxEvJmokpfI0+f8jeSoYEDGyFAfjxBjE9tasqw9wXiDzKyaXKU+DarJLesJQYRTrUfNqq ozQtjisv1chQrI8/zpcbtWKS2gnpUMsaoRp+dHWZrHNexoeOFd8vyODAQQI9XXNQ83VToP 6ZvybMUWya8WR2vFCvRObJjtN8WIN8k= X-MC-Unique: ote-O2TUNG24X4uEz2EbWQ-1 From: David Hildenbrand To: qemu-devel@nongnu.org Subject: [PATCH v3 1/7] memory: Introduce replay_discarded callback for RamDiscardManager Date: Fri, 30 Jul 2021 10:52:43 +0200 Message-Id: <20210730085249.8246-2-david@redhat.com> In-Reply-To: <20210730085249.8246-1-david@redhat.com> References: <20210730085249.8246-1-david@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 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 Content-Transfer-Encoding: quoted-printable Received-SPF: pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Received-SPF: pass client-ip=170.10.133.124; envelope-from=david@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -34 X-Spam_score: -3.5 X-Spam_bar: --- X-Spam_report: (-3.5 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.717, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, 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: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Eduardo Habkost , "Michael S. Tsirkin" , Pankaj Gupta , Juan Quintela , David Hildenbrand , "Dr. David Alan Gilbert" , Peter Xu , Marek Kedzierski , Alex Williamson , teawater , Paolo Bonzini , Andrey Gruzdev , Wei Yang Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail-DKIM: fail (Header signature does not verify) X-ZM-MESSAGEID: 1627635324204100001 Content-Type: text/plain; charset="utf-8" Introduce replay_discarded callback similar to our existing replay_populated callback, to be used my migration code to never migrate discarded memory. Acked-by: Peter Xu Signed-off-by: David Hildenbrand --- include/exec/memory.h | 21 +++++++++++++++++++++ softmmu/memory.c | 11 +++++++++++ 2 files changed, 32 insertions(+) diff --git a/include/exec/memory.h b/include/exec/memory.h index c3d417d317..93e972b55a 100644 --- a/include/exec/memory.h +++ b/include/exec/memory.h @@ -537,6 +537,7 @@ static inline void ram_discard_listener_init(RamDiscard= Listener *rdl, } =20 typedef int (*ReplayRamPopulate)(MemoryRegionSection *section, void *opaqu= e); +typedef void (*ReplayRamDiscard)(MemoryRegionSection *section, void *opaqu= e); =20 /* * RamDiscardManagerClass: @@ -625,6 +626,21 @@ struct RamDiscardManagerClass { MemoryRegionSection *section, ReplayRamPopulate replay_fn, void *opaque); =20 + /** + * @replay_discarded: + * + * Call the #ReplayRamDiscard callback for all discarded parts within = the + * #MemoryRegionSection via the #RamDiscardManager. + * + * @rdm: the #RamDiscardManager + * @section: the #MemoryRegionSection + * @replay_fn: the #ReplayRamDiscard callback + * @opaque: pointer to forward to the callback + */ + void (*replay_discarded)(const RamDiscardManager *rdm, + MemoryRegionSection *section, + ReplayRamDiscard replay_fn, void *opaque); + /** * @register_listener: * @@ -669,6 +685,11 @@ int ram_discard_manager_replay_populated(const RamDisc= ardManager *rdm, ReplayRamPopulate replay_fn, void *opaque); =20 +void ram_discard_manager_replay_discarded(const RamDiscardManager *rdm, + MemoryRegionSection *section, + ReplayRamDiscard replay_fn, + void *opaque); + void ram_discard_manager_register_listener(RamDiscardManager *rdm, RamDiscardListener *rdl, MemoryRegionSection *section); diff --git a/softmmu/memory.c b/softmmu/memory.c index bfedaf9c4d..cd86205627 100644 --- a/softmmu/memory.c +++ b/softmmu/memory.c @@ -2076,6 +2076,17 @@ int ram_discard_manager_replay_populated(const RamDi= scardManager *rdm, return rdmc->replay_populated(rdm, section, replay_fn, opaque); } =20 +void ram_discard_manager_replay_discarded(const RamDiscardManager *rdm, + MemoryRegionSection *section, + ReplayRamDiscard replay_fn, + void *opaque) +{ + RamDiscardManagerClass *rdmc =3D RAM_DISCARD_MANAGER_GET_CLASS(rdm); + + g_assert(rdmc->replay_discarded); + rdmc->replay_discarded(rdm, section, replay_fn, opaque); +} + void ram_discard_manager_register_listener(RamDiscardManager *rdm, RamDiscardListener *rdl, MemoryRegionSection *section) --=20 2.31.1 From nobody Fri May 10 19:07:11 2024 Delivered-To: importer@patchew.org Authentication-Results: mx.zohomail.com; dkim=fail; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=fail(p=none dis=none) header.from=redhat.com Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 1627635325638325.4976236216705; Fri, 30 Jul 2021 01:55:25 -0700 (PDT) Received: from localhost ([::1]:52776 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1m9OIe-00016i-JK for importer@patchew.org; Fri, 30 Jul 2021 04:55:24 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:42264) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1m9OGx-00071J-07 for qemu-devel@nongnu.org; Fri, 30 Jul 2021 04:53:39 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:42252) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1m9OGt-00076C-Ss for qemu-devel@nongnu.org; Fri, 30 Jul 2021 04:53:38 -0400 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-264-YoEhNnfRNQus7KhnW11tuA-1; Fri, 30 Jul 2021 04:53:33 -0400 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id E134818C43C2; Fri, 30 Jul 2021 08:53:31 +0000 (UTC) Received: from t480s.redhat.com (unknown [10.39.194.81]) by smtp.corp.redhat.com (Postfix) with ESMTP id 7209E60C05; Fri, 30 Jul 2021 08:53:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1627635214; 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=aknv+rhIU//dZzeWLjyq5A28L0a3a/nH+oAFCjD1Wpo=; b=A1VbVzIX7AY4jW9uWZLItC4VM/JySJ4h9stqCuPqqzbN1fC7qK2M20DJyPB3CfSEQ7yPGX 2AsDwTg3Kfw/x4OLFyAr0LoI72S3bJlm0ylaW1YAQTlyzK8imJC50oTK7k6bs018tfS1K+ sNhhnlLR8tQUtQNNsNNb7/FVnMfKKug= X-MC-Unique: YoEhNnfRNQus7KhnW11tuA-1 From: David Hildenbrand To: qemu-devel@nongnu.org Subject: [PATCH v3 2/7] virtio-mem: Implement replay_discarded RamDiscardManager callback Date: Fri, 30 Jul 2021 10:52:44 +0200 Message-Id: <20210730085249.8246-3-david@redhat.com> In-Reply-To: <20210730085249.8246-1-david@redhat.com> References: <20210730085249.8246-1-david@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 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 Content-Transfer-Encoding: quoted-printable Received-SPF: pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Received-SPF: pass client-ip=170.10.133.124; envelope-from=david@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -34 X-Spam_score: -3.5 X-Spam_bar: --- X-Spam_report: (-3.5 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.717, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, 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: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Eduardo Habkost , "Michael S. Tsirkin" , Pankaj Gupta , Juan Quintela , David Hildenbrand , "Dr. David Alan Gilbert" , Peter Xu , Marek Kedzierski , Alex Williamson , teawater , Paolo Bonzini , Andrey Gruzdev , Wei Yang Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail-DKIM: fail (Header signature does not verify) X-ZM-MESSAGEID: 1627635326333100001 Content-Type: text/plain; charset="utf-8" Implement it similar to the replay_populated callback. Acked-by: Peter Xu Signed-off-by: David Hildenbrand --- hw/virtio/virtio-mem.c | 58 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 58 insertions(+) diff --git a/hw/virtio/virtio-mem.c b/hw/virtio/virtio-mem.c index df91e454b2..284096ec5f 100644 --- a/hw/virtio/virtio-mem.c +++ b/hw/virtio/virtio-mem.c @@ -228,6 +228,38 @@ static int virtio_mem_for_each_plugged_section(const V= irtIOMEM *vmem, return ret; } =20 +static int virtio_mem_for_each_unplugged_section(const VirtIOMEM *vmem, + MemoryRegionSection *s, + void *arg, + virtio_mem_section_cb cb) +{ + unsigned long first_bit, last_bit; + uint64_t offset, size; + int ret =3D 0; + + first_bit =3D s->offset_within_region / vmem->bitmap_size; + first_bit =3D find_next_zero_bit(vmem->bitmap, vmem->bitmap_size, firs= t_bit); + while (first_bit < vmem->bitmap_size) { + MemoryRegionSection tmp =3D *s; + + offset =3D first_bit * vmem->block_size; + last_bit =3D find_next_bit(vmem->bitmap, vmem->bitmap_size, + first_bit + 1) - 1; + size =3D (last_bit - first_bit + 1) * vmem->block_size; + + if (!virito_mem_intersect_memory_section(&tmp, offset, size)) { + break; + } + ret =3D cb(&tmp, arg); + if (ret) { + break; + } + first_bit =3D find_next_zero_bit(vmem->bitmap, vmem->bitmap_size, + last_bit + 2); + } + return ret; +} + static int virtio_mem_notify_populate_cb(MemoryRegionSection *s, void *arg) { RamDiscardListener *rdl =3D arg; @@ -1170,6 +1202,31 @@ static int virtio_mem_rdm_replay_populated(const Ram= DiscardManager *rdm, virtio_mem_rdm_replay_populate= d_cb); } =20 +static int virtio_mem_rdm_replay_discarded_cb(MemoryRegionSection *s, + void *arg) +{ + struct VirtIOMEMReplayData *data =3D arg; + + ((ReplayRamDiscard)data->fn)(s, data->opaque); + return 0; +} + +static void virtio_mem_rdm_replay_discarded(const RamDiscardManager *rdm, + MemoryRegionSection *s, + ReplayRamDiscard replay_fn, + void *opaque) +{ + const VirtIOMEM *vmem =3D VIRTIO_MEM(rdm); + struct VirtIOMEMReplayData data =3D { + .fn =3D replay_fn, + .opaque =3D opaque, + }; + + g_assert(s->mr =3D=3D &vmem->memdev->mr); + virtio_mem_for_each_unplugged_section(vmem, s, &data, + virtio_mem_rdm_replay_discarded_= cb); +} + static void virtio_mem_rdm_register_listener(RamDiscardManager *rdm, RamDiscardListener *rdl, MemoryRegionSection *s) @@ -1234,6 +1291,7 @@ static void virtio_mem_class_init(ObjectClass *klass,= void *data) rdmc->get_min_granularity =3D virtio_mem_rdm_get_min_granularity; rdmc->is_populated =3D virtio_mem_rdm_is_populated; rdmc->replay_populated =3D virtio_mem_rdm_replay_populated; + rdmc->replay_discarded =3D virtio_mem_rdm_replay_discarded; rdmc->register_listener =3D virtio_mem_rdm_register_listener; rdmc->unregister_listener =3D virtio_mem_rdm_unregister_listener; } --=20 2.31.1 From nobody Fri May 10 19:07:11 2024 Delivered-To: importer@patchew.org Authentication-Results: mx.zohomail.com; dkim=fail; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=fail(p=none dis=none) header.from=redhat.com Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 1627635345874798.6252656516891; Fri, 30 Jul 2021 01:55:45 -0700 (PDT) Received: from localhost ([::1]:54450 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1m9OIy-0002JG-R0 for importer@patchew.org; Fri, 30 Jul 2021 04:55:44 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:42324) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1m9OHH-0007o3-L1 for qemu-devel@nongnu.org; Fri, 30 Jul 2021 04:53:59 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:53758) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1m9OHF-0007LB-3h for qemu-devel@nongnu.org; Fri, 30 Jul 2021 04:53:59 -0400 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-270-4J_GhIm4M1uDB11Zp18dUQ-1; Fri, 30 Jul 2021 04:53:53 -0400 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 13C1292506; Fri, 30 Jul 2021 08:53:52 +0000 (UTC) Received: from t480s.redhat.com (unknown [10.39.194.81]) by smtp.corp.redhat.com (Postfix) with ESMTP id 4760760C05; Fri, 30 Jul 2021 08:53:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1627635236; 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=qAe9o9QE3/gtatidVMRsDdO/u2RGc7z0fzt15wh7oZI=; b=Z6S6grU226tGxsF2Bo47v2UPjxMoGTsTbVjoWOA7LF9U3+tiKVLgm5HQwWfeP/P2j4NMuf RQnjgse/Akc9f3lJRnsYXEOAkUj9lLW84/+tN1bwCB737zfuwySgwfb4ckZym8WDP5ZQGZ k7NqDHHlQAbCN3AbK/DgOMtl7JWuOEk= X-MC-Unique: 4J_GhIm4M1uDB11Zp18dUQ-1 From: David Hildenbrand To: qemu-devel@nongnu.org Subject: [PATCH v3 3/7] migration/ram: Don't passs RAMState to migration_clear_memory_region_dirty_bitmap_*() Date: Fri, 30 Jul 2021 10:52:45 +0200 Message-Id: <20210730085249.8246-4-david@redhat.com> In-Reply-To: <20210730085249.8246-1-david@redhat.com> References: <20210730085249.8246-1-david@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 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 Content-Transfer-Encoding: quoted-printable Received-SPF: pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Received-SPF: pass client-ip=170.10.133.124; envelope-from=david@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -34 X-Spam_score: -3.5 X-Spam_bar: --- X-Spam_report: (-3.5 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.717, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, 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: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Eduardo Habkost , "Michael S. Tsirkin" , Pankaj Gupta , Juan Quintela , David Hildenbrand , "Dr. David Alan Gilbert" , Peter Xu , Marek Kedzierski , Alex Williamson , teawater , Paolo Bonzini , Andrey Gruzdev , Wei Yang Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail-DKIM: fail (Header signature does not verify) X-ZM-MESSAGEID: 1627635347331100001 Content-Type: text/plain; charset="utf-8" The parameter is unused, let's drop it. Signed-off-by: David Hildenbrand Reviewed-by: Peter Xu Reviewed-by: Philippe Mathieu-Daud=C3=A9 --- migration/ram.c | 13 +++++-------- 1 file changed, 5 insertions(+), 8 deletions(-) diff --git a/migration/ram.c b/migration/ram.c index 7a43bfd7af..bb908822d5 100644 --- a/migration/ram.c +++ b/migration/ram.c @@ -789,8 +789,7 @@ unsigned long migration_bitmap_find_dirty(RAMState *rs,= RAMBlock *rb, return find_next_bit(bitmap, size, start); } =20 -static void migration_clear_memory_region_dirty_bitmap(RAMState *rs, - RAMBlock *rb, +static void migration_clear_memory_region_dirty_bitmap(RAMBlock *rb, unsigned long page) { uint8_t shift; @@ -818,8 +817,7 @@ static void migration_clear_memory_region_dirty_bitmap(= RAMState *rs, } =20 static void -migration_clear_memory_region_dirty_bitmap_range(RAMState *rs, - RAMBlock *rb, +migration_clear_memory_region_dirty_bitmap_range(RAMBlock *rb, unsigned long start, unsigned long npages) { @@ -832,7 +830,7 @@ migration_clear_memory_region_dirty_bitmap_range(RAMSta= te *rs, * exclusive. */ for (i =3D chunk_start; i < chunk_end; i +=3D chunk_pages) { - migration_clear_memory_region_dirty_bitmap(rs, rb, i); + migration_clear_memory_region_dirty_bitmap(rb, i); } } =20 @@ -850,7 +848,7 @@ static inline bool migration_bitmap_clear_dirty(RAMStat= e *rs, * the page in the chunk we clear the remote dirty bitmap for all. * Clearing it earlier won't be a problem, but too late will. */ - migration_clear_memory_region_dirty_bitmap(rs, rb, page); + migration_clear_memory_region_dirty_bitmap(rb, page); =20 ret =3D test_and_clear_bit(page, rb->bmap); if (ret) { @@ -2777,8 +2775,7 @@ void qemu_guest_free_page_hint(void *addr, size_t len) * are initially set. Otherwise those skipped pages will be sent in * the next round after syncing from the memory region bitmap. */ - migration_clear_memory_region_dirty_bitmap_range(ram_state, block, - start, npages); + migration_clear_memory_region_dirty_bitmap_range(block, start, npa= ges); ram_state->migration_dirty_pages -=3D bitmap_count_one_with_offset(block->bmap, start, npa= ges); bitmap_clear(block->bmap, start, npages); --=20 2.31.1 From nobody Fri May 10 19:07:11 2024 Delivered-To: importer@patchew.org Authentication-Results: mx.zohomail.com; dkim=fail; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=fail(p=none dis=none) header.from=redhat.com Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 1627635418156491.6861174607128; Fri, 30 Jul 2021 01:56:58 -0700 (PDT) Received: from localhost ([::1]:59786 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1m9OK9-00064g-0L for importer@patchew.org; Fri, 30 Jul 2021 04:56:57 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:42480) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1m9OHT-00004w-P4 for qemu-devel@nongnu.org; Fri, 30 Jul 2021 04:54:11 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:27808) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1m9OHR-0007UZ-Qg for qemu-devel@nongnu.org; Fri, 30 Jul 2021 04:54:11 -0400 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-321-jfEq60CWOPmmHoT07Z9Pug-1; Fri, 30 Jul 2021 04:54:08 -0400 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 9A8241008060; Fri, 30 Jul 2021 08:54:06 +0000 (UTC) Received: from t480s.redhat.com (unknown [10.39.194.81]) by smtp.corp.redhat.com (Postfix) with ESMTP id 7434160C05; Fri, 30 Jul 2021 08:53:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1627635249; 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=A2WpFkIW1ti0FduzmfPQGFK+/qk0dU18K/Q3l2CPK88=; b=dYhnWoQFXPakGS5ibpJBat8QrWCyHBaKYDmDcU94NoyttbvgnwylHMHdKUaJ6o1wkdjMDN UKe9Fp+4VYxNLYlpNJ4k7ARX+pjPlT9YKSA6GK1Dyzg925C4CfiBKjtu7y6zyULTbm1+dn BiJOOLmuOx0G8H6h1bpPC3IwwAGQrck= X-MC-Unique: jfEq60CWOPmmHoT07Z9Pug-1 From: David Hildenbrand To: qemu-devel@nongnu.org Subject: [PATCH v3 4/7] migration/ram: Handle RAMBlocks with a RamDiscardManager on the migration source Date: Fri, 30 Jul 2021 10:52:46 +0200 Message-Id: <20210730085249.8246-5-david@redhat.com> In-Reply-To: <20210730085249.8246-1-david@redhat.com> References: <20210730085249.8246-1-david@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 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 Content-Transfer-Encoding: quoted-printable Received-SPF: pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Received-SPF: pass client-ip=216.205.24.124; envelope-from=david@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -34 X-Spam_score: -3.5 X-Spam_bar: --- X-Spam_report: (-3.5 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.717, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H3=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: Eduardo Habkost , "Michael S. Tsirkin" , Pankaj Gupta , Juan Quintela , David Hildenbrand , "Dr. David Alan Gilbert" , Peter Xu , Marek Kedzierski , Alex Williamson , teawater , Paolo Bonzini , Andrey Gruzdev , Wei Yang Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail-DKIM: fail (Header signature does not verify) X-ZM-MESSAGEID: 1627635419973100001 Content-Type: text/plain; charset="utf-8" We don't want to migrate memory that corresponds to discarded ranges as managed by a RamDiscardManager responsible for the mapped memory region of the RAMBlock. The content of these pages is essentially stale and without any guarantees for the VM ("logically unplugged"). Depending on the underlying memory type, even reading memory might populate memory on the source, resulting in an undesired memory consumption. Of course, on the destination, even writing a zeropage consumes memory, which we also want to avoid (similar to free page hinting). Currently, virtio-mem tries achieving that goal (not migrating "unplugged" memory that was discarded) by going via qemu_guest_free_page_hint() - but it's hackish and incomplete. For example, background snapshots still end up reading all memory, as they don't do bitmap syncs. Postcopy recovery code will re-add previously cleared bits to the dirty bitmap and migrate them. Let's consult the RamDiscardManager after setting up our dirty bitmap initially and when postcopy recovery code reinitializes it: clear corresponding bits in the dirty bitmaps (e.g., of the RAMBlock and inside KVM). It's important to fixup the dirty bitmap *after* our initial bitmap sync, such that the corresponding dirty bits in KVM are actually cleared. As colo is incompatible with discarding of RAM and inhibits it, we don't have to bother. Note: if a misbehaving guest would use discarded ranges after migration started we would still migrate that memory: however, then we already populated that memory on the migration source. Signed-off-by: David Hildenbrand Reviewed-by: Peter Xu --- migration/ram.c | 77 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 77 insertions(+) diff --git a/migration/ram.c b/migration/ram.c index bb908822d5..9776919faa 100644 --- a/migration/ram.c +++ b/migration/ram.c @@ -858,6 +858,60 @@ static inline bool migration_bitmap_clear_dirty(RAMSta= te *rs, return ret; } =20 +static void dirty_bitmap_clear_section(MemoryRegionSection *section, + void *opaque) +{ + const hwaddr offset =3D section->offset_within_region; + const hwaddr size =3D int128_get64(section->size); + const unsigned long start =3D offset >> TARGET_PAGE_BITS; + const unsigned long npages =3D size >> TARGET_PAGE_BITS; + RAMBlock *rb =3D section->mr->ram_block; + uint64_t *cleared_bits =3D opaque; + + /* + * We don't grab ram_state->bitmap_mutex because we expect to run + * only when starting migration or during postcopy recovery where + * we don't have concurrent access. + */ + if (!migration_in_postcopy() && !migrate_background_snapshot()) { + migration_clear_memory_region_dirty_bitmap_range(rb, start, npages= ); + } + *cleared_bits +=3D bitmap_count_one_with_offset(rb->bmap, start, npage= s); + bitmap_clear(rb->bmap, start, npages); +} + +/* + * Exclude all dirty pages from migration that fall into a discarded range= as + * managed by a RamDiscardManager responsible for the mapped memory region= of + * the RAMBlock. Clear the corresponding bits in the dirty bitmaps. + * + * Discarded pages ("logically unplugged") have undefined content and must + * not get migrated, because even reading these pages for migration might + * result in undesired behavior. + * + * Returns the number of cleared bits in the RAMBlock dirty bitmap. + * + * Note: The result is only stable while migration (precopy/postcopy). + */ +static uint64_t ramblock_dirty_bitmap_clear_discarded_pages(RAMBlock *rb) +{ + uint64_t cleared_bits =3D 0; + + if (rb->mr && rb->bmap && memory_region_has_ram_discard_manager(rb->mr= )) { + RamDiscardManager *rdm =3D memory_region_get_ram_discard_manager(r= b->mr); + MemoryRegionSection section =3D { + .mr =3D rb->mr, + .offset_within_region =3D 0, + .size =3D int128_make64(qemu_ram_get_used_length(rb)), + }; + + ram_discard_manager_replay_discarded(rdm, §ion, + dirty_bitmap_clear_section, + &cleared_bits); + } + return cleared_bits; +} + /* Called with RCU critical section */ static void ramblock_sync_dirty_bitmap(RAMState *rs, RAMBlock *rb) { @@ -2668,6 +2722,19 @@ static void ram_list_init_bitmaps(void) } } =20 +static void migration_bitmap_clear_discarded_pages(RAMState *rs) +{ + unsigned long pages; + RAMBlock *rb; + + RCU_READ_LOCK_GUARD(); + + RAMBLOCK_FOREACH_NOT_IGNORED(rb) { + pages =3D ramblock_dirty_bitmap_clear_discarded_pages(rb); + rs->migration_dirty_pages -=3D pages; + } +} + static void ram_init_bitmaps(RAMState *rs) { /* For memory_global_dirty_log_start below. */ @@ -2684,6 +2751,12 @@ static void ram_init_bitmaps(RAMState *rs) } qemu_mutex_unlock_ramlist(); qemu_mutex_unlock_iothread(); + + /* + * After an eventual first bitmap sync, fixup the initial bitmap + * containing all 1s to exclude any discarded pages from migration. + */ + migration_bitmap_clear_discarded_pages(rs); } =20 static int ram_init_all(RAMState **rsp) @@ -4112,6 +4185,10 @@ int ram_dirty_bitmap_reload(MigrationState *s, RAMBl= ock *block) */ bitmap_complement(block->bmap, block->bmap, nbits); =20 + /* Clear dirty bits of discarded ranges that we don't want to migrate.= */ + ramblock_dirty_bitmap_clear_discarded_pages(block); + + /* We'll recalculate migration_dirty_pages in ram_state_resume_prepare= (). */ trace_ram_dirty_bitmap_reload_complete(block->idstr); =20 /* --=20 2.31.1 From nobody Fri May 10 19:07:11 2024 Delivered-To: importer@patchew.org Authentication-Results: mx.zohomail.com; dkim=fail; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=fail(p=none dis=none) header.from=redhat.com Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 1627635443846463.1705443510268; Fri, 30 Jul 2021 01:57:23 -0700 (PDT) Received: from localhost ([::1]:33630 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1m9OKY-0007TP-Qr for importer@patchew.org; Fri, 30 Jul 2021 04:57:22 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:42588) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1m9OHc-0000YQ-Vu for qemu-devel@nongnu.org; Fri, 30 Jul 2021 04:54:21 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:58380) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1m9OHb-0007ay-8m for qemu-devel@nongnu.org; Fri, 30 Jul 2021 04:54:20 -0400 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-210-gBugYyXAMCmYCa7zgbsA0g-1; Fri, 30 Jul 2021 04:54:15 -0400 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 04C4D10851AE; Fri, 30 Jul 2021 08:54:14 +0000 (UTC) Received: from t480s.redhat.com (unknown [10.39.194.81]) by smtp.corp.redhat.com (Postfix) with ESMTP id EA12060C05; Fri, 30 Jul 2021 08:54:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1627635258; 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=MQNWaH8RlrrO5hzyddQ6ESB1VHn9VpoGXV3gKxmJawE=; b=CwYZeOgSoZCLvgDKKv0i4D7OfKEQ4C8mI2M+5n01OpWsrw7Si9YBdvAtE1US2qWrjfGO0d t7xvX8oUaBye9Jwq71a4y3ePOrz1qYAaR7nWInPJ3Uji2lZB3N3KOsuvdWgvUfcou59Us+ j21+m03v1aBTUxApKimE2FPa1eqDxKk= X-MC-Unique: gBugYyXAMCmYCa7zgbsA0g-1 From: David Hildenbrand To: qemu-devel@nongnu.org Subject: [PATCH v3 5/7] virtio-mem: Drop precopy notifier Date: Fri, 30 Jul 2021 10:52:47 +0200 Message-Id: <20210730085249.8246-6-david@redhat.com> In-Reply-To: <20210730085249.8246-1-david@redhat.com> References: <20210730085249.8246-1-david@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 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 Content-Transfer-Encoding: quoted-printable Received-SPF: pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Received-SPF: pass client-ip=170.10.133.124; envelope-from=david@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -34 X-Spam_score: -3.5 X-Spam_bar: --- X-Spam_report: (-3.5 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.717, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, 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: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Eduardo Habkost , "Michael S. Tsirkin" , Pankaj Gupta , Juan Quintela , David Hildenbrand , "Dr. David Alan Gilbert" , Peter Xu , Marek Kedzierski , Alex Williamson , teawater , Paolo Bonzini , Andrey Gruzdev , Wei Yang Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail-DKIM: fail (Header signature does not verify) X-ZM-MESSAGEID: 1627635445567100001 Content-Type: text/plain; charset="utf-8" Migration code now properly handles RAMBlocks which are indirectly managed by a RamDiscardManager. No need for manual handling via the free page optimization interface, let's get rid of it. Acked-by: Michael S. Tsirkin Acked-by: Peter Xu Signed-off-by: David Hildenbrand --- hw/virtio/virtio-mem.c | 34 ---------------------------------- include/hw/virtio/virtio-mem.h | 3 --- 2 files changed, 37 deletions(-) diff --git a/hw/virtio/virtio-mem.c b/hw/virtio/virtio-mem.c index 284096ec5f..d5a578142b 100644 --- a/hw/virtio/virtio-mem.c +++ b/hw/virtio/virtio-mem.c @@ -776,7 +776,6 @@ static void virtio_mem_device_realize(DeviceState *dev,= Error **errp) host_memory_backend_set_mapped(vmem->memdev, true); vmstate_register_ram(&vmem->memdev->mr, DEVICE(vmem)); qemu_register_reset(virtio_mem_system_reset, vmem); - precopy_add_notifier(&vmem->precopy_notifier); =20 /* * Set ourselves as RamDiscardManager before the plug handler maps the @@ -796,7 +795,6 @@ static void virtio_mem_device_unrealize(DeviceState *de= v) * found via an address space anymore. Unset ourselves. */ memory_region_set_ram_discard_manager(&vmem->memdev->mr, NULL); - precopy_remove_notifier(&vmem->precopy_notifier); qemu_unregister_reset(virtio_mem_system_reset, vmem); vmstate_unregister_ram(&vmem->memdev->mr, DEVICE(vmem)); host_memory_backend_set_mapped(vmem->memdev, false); @@ -1089,43 +1087,11 @@ static void virtio_mem_set_block_size(Object *obj, = Visitor *v, const char *name, vmem->block_size =3D value; } =20 -static int virtio_mem_precopy_exclude_range_cb(const VirtIOMEM *vmem, void= *arg, - uint64_t offset, uint64_t s= ize) -{ - void * const host =3D qemu_ram_get_host_addr(vmem->memdev->mr.ram_bloc= k); - - qemu_guest_free_page_hint(host + offset, size); - return 0; -} - -static void virtio_mem_precopy_exclude_unplugged(VirtIOMEM *vmem) -{ - virtio_mem_for_each_unplugged_range(vmem, NULL, - virtio_mem_precopy_exclude_range_c= b); -} - -static int virtio_mem_precopy_notify(NotifierWithReturn *n, void *data) -{ - VirtIOMEM *vmem =3D container_of(n, VirtIOMEM, precopy_notifier); - PrecopyNotifyData *pnd =3D data; - - switch (pnd->reason) { - case PRECOPY_NOTIFY_AFTER_BITMAP_SYNC: - virtio_mem_precopy_exclude_unplugged(vmem); - break; - default: - break; - } - - return 0; -} - static void virtio_mem_instance_init(Object *obj) { VirtIOMEM *vmem =3D VIRTIO_MEM(obj); =20 notifier_list_init(&vmem->size_change_notifiers); - vmem->precopy_notifier.notify =3D virtio_mem_precopy_notify; QLIST_INIT(&vmem->rdl_list); =20 object_property_add(obj, VIRTIO_MEM_SIZE_PROP, "size", virtio_mem_get_= size, diff --git a/include/hw/virtio/virtio-mem.h b/include/hw/virtio/virtio-mem.h index 9a6e348fa2..a5dd6a493b 100644 --- a/include/hw/virtio/virtio-mem.h +++ b/include/hw/virtio/virtio-mem.h @@ -65,9 +65,6 @@ struct VirtIOMEM { /* notifiers to notify when "size" changes */ NotifierList size_change_notifiers; =20 - /* don't migrate unplugged memory */ - NotifierWithReturn precopy_notifier; - /* listeners to notify on plug/unplug activity. */ QLIST_HEAD(, RamDiscardListener) rdl_list; }; --=20 2.31.1 From nobody Fri May 10 19:07:11 2024 Delivered-To: importer@patchew.org Authentication-Results: mx.zohomail.com; dkim=fail; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=fail(p=none dis=none) header.from=redhat.com Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 1627635512258237.37302906498803; Fri, 30 Jul 2021 01:58:32 -0700 (PDT) Received: from localhost ([::1]:38066 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1m9OLf-00026V-9k for importer@patchew.org; Fri, 30 Jul 2021 04:58:31 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:42628) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1m9OHq-0000sz-UB for qemu-devel@nongnu.org; Fri, 30 Jul 2021 04:54:34 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:34778) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1m9OHp-0007jm-29 for qemu-devel@nongnu.org; Fri, 30 Jul 2021 04:54:34 -0400 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-271-KdU4yM9iNfK0rKRiV4IhDw-1; Fri, 30 Jul 2021 04:54:29 -0400 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 136F518C8C01; Fri, 30 Jul 2021 08:54:28 +0000 (UTC) Received: from t480s.redhat.com (unknown [10.39.194.81]) by smtp.corp.redhat.com (Postfix) with ESMTP id 52E2D60C05; Fri, 30 Jul 2021 08:54:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1627635272; 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=143OSadT7GLgT/K6CwuB7rvejjP4K57nHhl0WuqL3vE=; b=GLmh2tLOtegmA4xyuX2ZcP+OQ3gsyu5nXUYf4T76twHzUskz8O2XmINsCFMPCdkDNS1mmw 78x1jBSdcWG+3Wh8eMQLxErtMsUCDGj4HmjQxHZZyZH9gZrIMg9uQjDWWyFv3ucCKaGHYJ rXmCyng/QKwS7vQe7xI/jPGDwQQ4thA= X-MC-Unique: KdU4yM9iNfK0rKRiV4IhDw-1 From: David Hildenbrand To: qemu-devel@nongnu.org Subject: [PATCH v3 6/7] migration/postcopy: Handle RAMBlocks with a RamDiscardManager on the destination Date: Fri, 30 Jul 2021 10:52:48 +0200 Message-Id: <20210730085249.8246-7-david@redhat.com> In-Reply-To: <20210730085249.8246-1-david@redhat.com> References: <20210730085249.8246-1-david@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 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 Content-Transfer-Encoding: quoted-printable Received-SPF: pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Received-SPF: pass client-ip=216.205.24.124; envelope-from=david@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -34 X-Spam_score: -3.5 X-Spam_bar: --- X-Spam_report: (-3.5 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.717, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H3=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: Eduardo Habkost , "Michael S. Tsirkin" , Pankaj Gupta , Juan Quintela , David Hildenbrand , "Dr. David Alan Gilbert" , Peter Xu , Marek Kedzierski , Alex Williamson , teawater , Paolo Bonzini , Andrey Gruzdev , Wei Yang Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail-DKIM: fail (Header signature does not verify) X-ZM-MESSAGEID: 1627635514022100001 Content-Type: text/plain; charset="utf-8" Currently, when someone (i.e., the VM) accesses discarded parts inside a RAMBlock with a RamDiscardManager managing the corresponding mapped memory region, postcopy will request migration of the corresponding page from the source. The source, however, will never answer, because it refuses to migrate such pages with undefined content ("logically unplugged"): the pages are never dirty, and get_queued_page() will consequently skip processing these postcopy requests. Especially reading discarded ("logically unplugged") ranges is supposed to work in some setups (for example with current virtio-mem), although it barely ever happens: still, not placing a page would currently stall the VM, as it cannot make forward progress. Let's check the state via the RamDiscardManager (the state e.g., of virtio-mem is migrated during precopy) and avoid sending a request that will never get answered. Place a fresh zero page instead to keep the VM working. This is the same behavior that would happen automatically without userfaultfd being active, when accessing virtual memory regions without populated pages -- "populate on demand". For now, there are valid cases (as documented in the virtio-mem spec) where a VM might read discarded memory; in the future, we will disallow that. Then, we might want to handle that case differently, e.g., warning the user that the VM seems to be mis-behaving. Signed-off-by: David Hildenbrand --- migration/postcopy-ram.c | 31 +++++++++++++++++++++++++++---- migration/ram.c | 21 +++++++++++++++++++++ migration/ram.h | 1 + 3 files changed, 49 insertions(+), 4 deletions(-) diff --git a/migration/postcopy-ram.c b/migration/postcopy-ram.c index 2e9697bdd2..38cdfc09c3 100644 --- a/migration/postcopy-ram.c +++ b/migration/postcopy-ram.c @@ -671,6 +671,29 @@ int postcopy_wake_shared(struct PostCopyFD *pcfd, return ret; } =20 +static int postcopy_request_page(MigrationIncomingState *mis, RAMBlock *rb, + ram_addr_t start, uint64_t haddr) +{ + void *aligned =3D (void *)(uintptr_t)(haddr & -qemu_ram_pagesize(rb)); + + /* + * Discarded pages (via RamDiscardManager) are never migrated. On unli= kely + * access, place a zeropage, which will also set the relevant bits in = the + * recv_bitmap accordingly, so we won't try placing a zeropage twice. + * + * Checking a single bit is sufficient to handle pagesize > TPS as eit= her + * all relevant bits are set or not. + */ + assert(QEMU_IS_ALIGNED(start, qemu_ram_pagesize(rb))); + if (ramblock_page_is_discarded(rb, start)) { + bool received =3D ramblock_recv_bitmap_test_byte_offset(rb, start); + + return received ? 0 : postcopy_place_page_zero(mis, aligned, rb); + } + + return migrate_send_rp_req_pages(mis, rb, start, haddr); +} + /* * Callback from shared fault handlers to ask for a page, * the page must be specified by a RAMBlock and an offset in that rb @@ -690,7 +713,7 @@ int postcopy_request_shared_page(struct PostCopyFD *pcf= d, RAMBlock *rb, qemu_ram_get_idstr(rb), rb_offset); return postcopy_wake_shared(pcfd, client_addr, rb); } - migrate_send_rp_req_pages(mis, rb, aligned_rbo, client_addr); + postcopy_request_page(mis, rb, aligned_rbo, client_addr); return 0; } =20 @@ -984,8 +1007,8 @@ retry: * Send the request to the source - we want to request one * of our host page sizes (which is >=3D TPS) */ - ret =3D migrate_send_rp_req_pages(mis, rb, rb_offset, - msg.arg.pagefault.address); + ret =3D postcopy_request_page(mis, rb, rb_offset, + msg.arg.pagefault.address); if (ret) { /* May be network failure, try to wait for recovery */ if (ret =3D=3D -EIO && postcopy_pause_fault_thread(mis)) { @@ -993,7 +1016,7 @@ retry: goto retry; } else { /* This is a unavoidable fault */ - error_report("%s: migrate_send_rp_req_pages() get %d", + error_report("%s: postcopy_request_page() get %d", __func__, ret); break; } diff --git a/migration/ram.c b/migration/ram.c index 9776919faa..01cea01774 100644 --- a/migration/ram.c +++ b/migration/ram.c @@ -912,6 +912,27 @@ static uint64_t ramblock_dirty_bitmap_clear_discarded_= pages(RAMBlock *rb) return cleared_bits; } =20 +/* + * Check if a host-page aligned page falls into a discarded range as manag= ed by + * a RamDiscardManager responsible for the mapped memory region of the RAM= Block. + * + * Note: The result is only stable while migration (precopy/postcopy). + */ +bool ramblock_page_is_discarded(RAMBlock *rb, ram_addr_t start) +{ + if (rb->mr && memory_region_has_ram_discard_manager(rb->mr)) { + RamDiscardManager *rdm =3D memory_region_get_ram_discard_manager(r= b->mr); + MemoryRegionSection section =3D { + .mr =3D rb->mr, + .offset_within_region =3D start, + .size =3D int128_get64(qemu_ram_pagesize(rb)), + }; + + return !ram_discard_manager_is_populated(rdm, §ion); + } + return false; +} + /* Called with RCU critical section */ static void ramblock_sync_dirty_bitmap(RAMState *rs, RAMBlock *rb) { diff --git a/migration/ram.h b/migration/ram.h index 4833e9fd5b..dda1988f3d 100644 --- a/migration/ram.h +++ b/migration/ram.h @@ -72,6 +72,7 @@ void ramblock_recv_bitmap_set_range(RAMBlock *rb, void *h= ost_addr, size_t nr); int64_t ramblock_recv_bitmap_send(QEMUFile *file, const char *block_name); int ram_dirty_bitmap_reload(MigrationState *s, RAMBlock *rb); +bool ramblock_page_is_discarded(RAMBlock *rb, ram_addr_t start); =20 /* ram cache */ int colo_init_ram_cache(void); --=20 2.31.1 From nobody Fri May 10 19:07:11 2024 Delivered-To: importer@patchew.org Authentication-Results: mx.zohomail.com; dkim=fail; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=fail(p=none dis=none) header.from=redhat.com Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 1627635438561294.5472144556883; Fri, 30 Jul 2021 01:57:18 -0700 (PDT) Received: from localhost ([::1]:33196 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1m9OKT-0007BF-Il for importer@patchew.org; Fri, 30 Jul 2021 04:57:17 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:42708) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1m9OHx-0001FH-Ct for qemu-devel@nongnu.org; Fri, 30 Jul 2021 04:54:41 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:21757) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1m9OHu-0007nG-Ds for qemu-devel@nongnu.org; Fri, 30 Jul 2021 04:54:41 -0400 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-118-C72uVisFOzOGOpwqzuYgKw-1; Fri, 30 Jul 2021 04:54:36 -0400 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 300F293920; Fri, 30 Jul 2021 08:54:35 +0000 (UTC) Received: from t480s.redhat.com (unknown [10.39.194.81]) by smtp.corp.redhat.com (Postfix) with ESMTP id 7CBD760C13; Fri, 30 Jul 2021 08:54:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1627635277; 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=12IgdDqbAG2zdxCmsPRWEcu/fd32i5J9A3qDO5CdSJc=; b=RPNrcmcDC3zD3HfHTrzWPBiIMlw4L/AwaoVjc27/jj4PIqR3z2qCRiUYYfUm+5fjmBE8JY WlNENPajihS+z6l3gf2YVnU8v3VhNWyA9aBCQ1ZpajVe0p9I1pM3hLKCtgBQxvLK5ZKh27 Bnopf3CuYP5Y/SYapC4KE7z3WnPLJfw= X-MC-Unique: C72uVisFOzOGOpwqzuYgKw-1 From: David Hildenbrand To: qemu-devel@nongnu.org Subject: [PATCH v3 7/7] migration/ram: Handle RAMBlocks with a RamDiscardManager on background snapshots Date: Fri, 30 Jul 2021 10:52:49 +0200 Message-Id: <20210730085249.8246-8-david@redhat.com> In-Reply-To: <20210730085249.8246-1-david@redhat.com> References: <20210730085249.8246-1-david@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 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 Content-Transfer-Encoding: quoted-printable Received-SPF: pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Received-SPF: pass client-ip=170.10.133.124; envelope-from=david@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -34 X-Spam_score: -3.5 X-Spam_bar: --- X-Spam_report: (-3.5 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.717, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, 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: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Eduardo Habkost , "Michael S. Tsirkin" , Pankaj Gupta , Juan Quintela , David Hildenbrand , "Dr. David Alan Gilbert" , Peter Xu , Marek Kedzierski , Alex Williamson , teawater , Paolo Bonzini , Andrey Gruzdev , Wei Yang Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail-DKIM: fail (Header signature does not verify) X-ZM-MESSAGEID: 1627635439227100001 Content-Type: text/plain; charset="utf-8" We already don't ever migrate memory that corresponds to discarded ranges as managed by a RamDiscardManager responsible for the mapped memory region of the RAMBlock. virtio-mem uses this mechanism to logically unplug parts of a RAMBlock. Right now, we still populate zeropages for the whole usable part of the RAMBlock, which is undesired because: 1. Even populating the shared zeropage will result in memory getting consumed for page tables. 2. Memory backends without a shared zeropage (like hugetlbfs and shmem) will populate an actual, fresh page, resulting in an unintended memory consumption. Discarded ("logically unplugged") parts have to remain discarded. As these pages are never part of the migration stream, there is no need to track modifications via userfaultfd WP reliably for these parts. Further, any writes to these ranges by the VM are invalid and the behavior is undefined. Note that Linux only supports userfaultfd WP on private anonymous memory for now, which usually results in the shared zeropage getting populated. The issue will become more relevant once userfaultfd WP supports shmem and hugetlb. Acked-by: Peter Xu Signed-off-by: David Hildenbrand --- migration/ram.c | 53 +++++++++++++++++++++++++++++++++++++++++-------- 1 file changed, 45 insertions(+), 8 deletions(-) diff --git a/migration/ram.c b/migration/ram.c index 01cea01774..fd5949734e 100644 --- a/migration/ram.c +++ b/migration/ram.c @@ -1639,6 +1639,28 @@ out: return ret; } =20 +static inline void populate_range(RAMBlock *block, hwaddr offset, hwaddr s= ize) +{ + char *ptr =3D (char *) block->host; + + for (; offset < size; offset +=3D qemu_real_host_page_size) { + char tmp =3D *(ptr + offset); + + /* Don't optimize the read out */ + asm volatile("" : "+r" (tmp)); + } +} + +static inline int populate_section(MemoryRegionSection *section, void *opa= que) +{ + const hwaddr size =3D int128_get64(section->size); + hwaddr offset =3D section->offset_within_region; + RAMBlock *block =3D section->mr->ram_block; + + populate_range(block, offset, size); + return 0; +} + /* * ram_block_populate_pages: populate memory in the RAM block by reading * an integer from the beginning of each page. @@ -1648,16 +1670,31 @@ out: * * @block: RAM block to populate */ -static void ram_block_populate_pages(RAMBlock *block) +static void ram_block_populate_pages(RAMBlock *rb) { - char *ptr =3D (char *) block->host; - - for (ram_addr_t offset =3D 0; offset < block->used_length; - offset +=3D qemu_real_host_page_size) { - char tmp =3D *(ptr + offset); + /* + * Skip populating all pages that fall into a discarded range as manag= ed by + * a RamDiscardManager responsible for the mapped memory region of the + * RAMBlock. Such discarded ("logically unplugged") parts of a RAMBlock + * must not get populated automatically. We don't have to track + * modifications via userfaultfd WP reliably, because these pages will + * not be part of the migration stream either way -- see + * ramblock_dirty_bitmap_exclude_discarded_pages(). + * + * Note: The result is only stable while migration (precopy/postcopy). + */ + if (rb->mr && memory_region_has_ram_discard_manager(rb->mr)) { + RamDiscardManager *rdm =3D memory_region_get_ram_discard_manager(r= b->mr); + MemoryRegionSection section =3D { + .mr =3D rb->mr, + .offset_within_region =3D 0, + .size =3D rb->mr->size, + }; =20 - /* Don't optimize the read out */ - asm volatile("" : "+r" (tmp)); + ram_discard_manager_replay_populated(rdm, §ion, + populate_section, NULL); + } else { + populate_range(rb, 0, qemu_ram_get_used_length(rb)); } } =20 --=20 2.31.1