From patchwork Thu Jan 12 16:43:56 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Hildenbrand X-Patchwork-Id: 13098377 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org 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 smtp.lore.kernel.org (Postfix) with ESMTPS id 5C1C7C54EBC for ; Thu, 12 Jan 2023 16:45:16 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1pG0gZ-0004CD-R9; Thu, 12 Jan 2023 11:44:15 -0500 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 1pG0gW-0004Bp-F0 for qemu-devel@nongnu.org; Thu, 12 Jan 2023 11:44:13 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1pG0gU-0000d5-R6 for qemu-devel@nongnu.org; Thu, 12 Jan 2023 11:44:12 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1673541850; 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=ZlzWe9tPcq9k0dBwflFDgLiMtDnZGZ0Ab2cce46ADqY=; b=e9Sf3xW6cczYVFhiDfbemD40tTa+EhruJyS9jLpanGVgK3V5CI3BPoMyrMYnd4VQhx9wf6 m2QQ8gs8pXriRpsqnB92j3BPRk7Z0owxcemNDmm6NcPpXr8BlW7qJv5ApcO8c6rOMJCZPB s4mcoo5yLE2dvalaIWCYnS3xvBH+5eY= 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-6-d1gNbktON2CBHtWWH4JYgQ-1; Thu, 12 Jan 2023 11:44:08 -0500 X-MC-Unique: d1gNbktON2CBHtWWH4JYgQ-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.rdu2.redhat.com [10.11.54.2]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 77BFD100F905 for ; Thu, 12 Jan 2023 16:44:08 +0000 (UTC) Received: from t480s.fritz.box (unknown [10.39.193.30]) by smtp.corp.redhat.com (Postfix) with ESMTP id B36224078903; Thu, 12 Jan 2023 16:44:06 +0000 (UTC) From: David Hildenbrand To: qemu-devel@nongnu.org Cc: David Hildenbrand , "Dr . David Alan Gilbert" , Juan Quintela , Peter Xu , "Michael S . Tsirkin" , Michal Privoznik Subject: [PATCH v3 1/8] migration/savevm: Move more savevm handling into vmstate_save() Date: Thu, 12 Jan 2023 17:43:56 +0100 Message-Id: <20230112164403.105085-2-david@redhat.com> In-Reply-To: <20230112164403.105085-1-david@redhat.com> References: <20230112164403.105085-1-david@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.2 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: -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_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: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Let's move more code into vmstate_save(), reducing code duplication and preparing for reuse of vmstate_save() in qemu_savevm_state_setup(). We have to move vmstate_save() to make the compiler happy. We'll now also trace from qemu_save_device_state(). Signed-off-by: David Hildenbrand --- migration/savevm.c | 79 ++++++++++++++++++++++------------------------ 1 file changed, 37 insertions(+), 42 deletions(-) diff --git a/migration/savevm.c b/migration/savevm.c index a0cdb714f7..d8830297e4 100644 --- a/migration/savevm.c +++ b/migration/savevm.c @@ -897,17 +897,6 @@ static void vmstate_save_old_style(QEMUFile *f, SaveStateEntry *se, } } -static int vmstate_save(QEMUFile *f, SaveStateEntry *se, - JSONWriter *vmdesc) -{ - trace_vmstate_save(se->idstr, se->vmsd ? se->vmsd->name : "(old)"); - if (!se->vmsd) { - vmstate_save_old_style(f, se, vmdesc); - return 0; - } - return vmstate_save_state(f, se->vmsd, se->opaque, vmdesc); -} - /* * Write the header for device section (QEMU_VM_SECTION START/END/PART/FULL) */ @@ -941,6 +930,43 @@ static void save_section_footer(QEMUFile *f, SaveStateEntry *se) } } +static int vmstate_save(QEMUFile *f, SaveStateEntry *se, JSONWriter *vmdesc) +{ + int ret; + + if ((!se->ops || !se->ops->save_state) && !se->vmsd) { + return 0; + } + if (se->vmsd && !vmstate_save_needed(se->vmsd, se->opaque)) { + trace_savevm_section_skip(se->idstr, se->section_id); + return 0; + } + + trace_savevm_section_start(se->idstr, se->section_id); + save_section_header(f, se, QEMU_VM_SECTION_FULL); + if (vmdesc) { + json_writer_start_object(vmdesc, NULL); + json_writer_str(vmdesc, "name", se->idstr); + json_writer_int64(vmdesc, "instance_id", se->instance_id); + } + + trace_vmstate_save(se->idstr, se->vmsd ? se->vmsd->name : "(old)"); + if (!se->vmsd) { + vmstate_save_old_style(f, se, vmdesc); + } else { + ret = vmstate_save_state(f, se->vmsd, se->opaque, vmdesc); + if (ret) { + return ret; + } + } + + trace_savevm_section_end(se->idstr, se->section_id, 0); + save_section_footer(f, se); + if (vmdesc) { + json_writer_end_object(vmdesc); + } + return 0; +} /** * qemu_savevm_command_send: Send a 'QEMU_VM_COMMAND' type element with the * command and associated data. @@ -1374,31 +1400,11 @@ int qemu_savevm_state_complete_precopy_non_iterable(QEMUFile *f, json_writer_int64(vmdesc, "page_size", qemu_target_page_size()); json_writer_start_array(vmdesc, "devices"); QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { - - if ((!se->ops || !se->ops->save_state) && !se->vmsd) { - continue; - } - if (se->vmsd && !vmstate_save_needed(se->vmsd, se->opaque)) { - trace_savevm_section_skip(se->idstr, se->section_id); - continue; - } - - trace_savevm_section_start(se->idstr, se->section_id); - - json_writer_start_object(vmdesc, NULL); - json_writer_str(vmdesc, "name", se->idstr); - json_writer_int64(vmdesc, "instance_id", se->instance_id); - - save_section_header(f, se, QEMU_VM_SECTION_FULL); ret = vmstate_save(f, se, vmdesc); if (ret) { qemu_file_set_error(f, ret); return ret; } - trace_savevm_section_end(se->idstr, se->section_id, 0); - save_section_footer(f, se); - - json_writer_end_object(vmdesc); } if (inactivate_disks) { @@ -1594,21 +1600,10 @@ int qemu_save_device_state(QEMUFile *f) if (se->is_ram) { continue; } - if ((!se->ops || !se->ops->save_state) && !se->vmsd) { - continue; - } - if (se->vmsd && !vmstate_save_needed(se->vmsd, se->opaque)) { - continue; - } - - save_section_header(f, se, QEMU_VM_SECTION_FULL); - ret = vmstate_save(f, se, NULL); if (ret) { return ret; } - - save_section_footer(f, se); } qemu_put_byte(f, QEMU_VM_EOF); From patchwork Thu Jan 12 16:43:57 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Hildenbrand X-Patchwork-Id: 13098376 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org 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 smtp.lore.kernel.org (Postfix) with ESMTPS id 830E3C54EBD for ; Thu, 12 Jan 2023 16:45:14 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1pG0gd-0004FJ-1r; Thu, 12 Jan 2023 11:44:20 -0500 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 1pG0ga-0004Cd-2T for qemu-devel@nongnu.org; Thu, 12 Jan 2023 11:44:16 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1pG0gX-0000dS-CQ for qemu-devel@nongnu.org; Thu, 12 Jan 2023 11:44:15 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1673541852; 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=in2t5r/y8I6GAT2Myo61i75/xnCu58xNANQ1MspLwLI=; b=L3QxOK4CsHDhVl+LDSzc7C0c7EhLZzMoFeHetR0v+pILvOY+mqhMfNke5RJDI2sAbe7avD 0RvKPpcHCd4M8YWj5uVJExsR+YKdBYI0dpImgURpNvtTRIAHm3NGp50f0GSjrBS5ZDF2ff nTFZNEWuwTnCGt0MZbrBCEOUWYwFVh4= 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-446-4mNAv2I1OFK5my1FBTfhyw-1; Thu, 12 Jan 2023 11:44:11 -0500 X-MC-Unique: 4mNAv2I1OFK5my1FBTfhyw-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.rdu2.redhat.com [10.11.54.2]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id E2305882821 for ; Thu, 12 Jan 2023 16:44:10 +0000 (UTC) Received: from t480s.fritz.box (unknown [10.39.193.30]) by smtp.corp.redhat.com (Postfix) with ESMTP id D61FC4078903; Thu, 12 Jan 2023 16:44:08 +0000 (UTC) From: David Hildenbrand To: qemu-devel@nongnu.org Cc: David Hildenbrand , "Dr . David Alan Gilbert" , Juan Quintela , Peter Xu , "Michael S . Tsirkin" , Michal Privoznik Subject: [PATCH v3 2/8] migration/savevm: Prepare vmdesc json writer in qemu_savevm_state_setup() Date: Thu, 12 Jan 2023 17:43:57 +0100 Message-Id: <20230112164403.105085-3-david@redhat.com> In-Reply-To: <20230112164403.105085-1-david@redhat.com> References: <20230112164403.105085-1-david@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.2 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: -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_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: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org ... and store it in the migration state. This is a preparation for storing selected vmds's already in qemu_savevm_state_setup(). Signed-off-by: David Hildenbrand Reviewed-by: Dr. David Alan Gilbert --- migration/migration.c | 4 ++++ migration/migration.h | 4 ++++ migration/savevm.c | 18 ++++++++++++------ 3 files changed, 20 insertions(+), 6 deletions(-) diff --git a/migration/migration.c b/migration/migration.c index 52b5d39244..1d33a7efa0 100644 --- a/migration/migration.c +++ b/migration/migration.c @@ -2170,6 +2170,9 @@ void migrate_init(MigrationState *s) s->vm_was_running = false; s->iteration_initial_bytes = 0; s->threshold_size = 0; + + json_writer_free(s->vmdesc); + s->vmdesc = NULL; } int migrate_add_blocker_internal(Error *reason, Error **errp) @@ -4445,6 +4448,7 @@ static void migration_instance_finalize(Object *obj) qemu_sem_destroy(&ms->rp_state.rp_sem); qemu_sem_destroy(&ms->postcopy_qemufile_src_sem); error_free(ms->error); + json_writer_free(ms->vmdesc); } static void migration_instance_init(Object *obj) diff --git a/migration/migration.h b/migration/migration.h index ae4ffd3454..66511ce532 100644 --- a/migration/migration.h +++ b/migration/migration.h @@ -17,6 +17,7 @@ #include "exec/cpu-common.h" #include "hw/qdev-core.h" #include "qapi/qapi-types-migration.h" +#include "qapi/qmp/json-writer.h" #include "qemu/thread.h" #include "qemu/coroutine_int.h" #include "io/channel.h" @@ -366,6 +367,9 @@ struct MigrationState { * This save hostname when out-going migration starts */ char *hostname; + + /* QEMU_VM_VMDESCRIPTION content filled for all non-iterable devices. */ + JSONWriter *vmdesc; }; void migrate_set_state(int *state, int old_state, int new_state); diff --git a/migration/savevm.c b/migration/savevm.c index d8830297e4..ff2b8d0064 100644 --- a/migration/savevm.c +++ b/migration/savevm.c @@ -42,7 +42,6 @@ #include "postcopy-ram.h" #include "qapi/error.h" #include "qapi/qapi-commands-migration.h" -#include "qapi/qmp/json-writer.h" #include "qapi/clone-visitor.h" #include "qapi/qapi-builtin-visit.h" #include "qapi/qmp/qerror.h" @@ -1189,10 +1188,16 @@ bool qemu_savevm_state_guest_unplug_pending(void) void qemu_savevm_state_setup(QEMUFile *f) { + MigrationState *ms = migrate_get_current(); SaveStateEntry *se; Error *local_err = NULL; int ret; + ms->vmdesc = json_writer_new(false); + json_writer_start_object(ms->vmdesc, NULL); + json_writer_int64(ms->vmdesc, "page_size", qemu_target_page_size()); + json_writer_start_array(ms->vmdesc, "devices"); + trace_savevm_state_setup(); QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { if (!se->ops || !se->ops->save_setup) { @@ -1390,15 +1395,12 @@ int qemu_savevm_state_complete_precopy_non_iterable(QEMUFile *f, bool in_postcopy, bool inactivate_disks) { - g_autoptr(JSONWriter) vmdesc = NULL; + MigrationState *ms = migrate_get_current(); + JSONWriter *vmdesc = ms->vmdesc; int vmdesc_len; SaveStateEntry *se; int ret; - vmdesc = json_writer_new(false); - json_writer_start_object(vmdesc, NULL); - json_writer_int64(vmdesc, "page_size", qemu_target_page_size()); - json_writer_start_array(vmdesc, "devices"); QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { ret = vmstate_save(f, se, vmdesc); if (ret) { @@ -1433,6 +1435,10 @@ int qemu_savevm_state_complete_precopy_non_iterable(QEMUFile *f, qemu_put_buffer(f, (uint8_t *)json_writer_get(vmdesc), vmdesc_len); } + /* Free it now to detect any inconsistencies. */ + json_writer_free(vmdesc); + ms->vmdesc = NULL; + return 0; } From patchwork Thu Jan 12 16:43:58 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Hildenbrand X-Patchwork-Id: 13098442 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org 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 smtp.lore.kernel.org (Postfix) with ESMTPS id 8FFDBC54EBD for ; Thu, 12 Jan 2023 16:46:08 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1pG0gf-0004HA-CZ; Thu, 12 Jan 2023 11:44:21 -0500 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 1pG0gc-0004FL-KH for qemu-devel@nongnu.org; Thu, 12 Jan 2023 11:44:18 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1pG0gb-0000dl-5M for qemu-devel@nongnu.org; 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Thu, 12 Jan 2023 16:44:13 +0000 (UTC) Received: from t480s.fritz.box (unknown [10.39.193.30]) by smtp.corp.redhat.com (Postfix) with ESMTP id 51DEE4078903; Thu, 12 Jan 2023 16:44:11 +0000 (UTC) From: David Hildenbrand To: qemu-devel@nongnu.org Cc: David Hildenbrand , "Dr . David Alan Gilbert" , Juan Quintela , Peter Xu , "Michael S . Tsirkin" , Michal Privoznik Subject: [PATCH v3 3/8] migration/savevm: Allow immutable device state to be migrated early (i.e., before RAM) Date: Thu, 12 Jan 2023 17:43:58 +0100 Message-Id: <20230112164403.105085-4-david@redhat.com> In-Reply-To: <20230112164403.105085-1-david@redhat.com> References: <20230112164403.105085-1-david@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.2 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: -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_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: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org For virtio-mem, we want to have the plugged/unplugged state of memory blocks available before migrating any actual RAM content, and perform sanity checks before touching anything on the destination. This information is immutable on the migration source while migration is active, We want to use this information for proper preallocation support with migration: currently, we don't preallocate memory on the migration target, and especially with hugetlb, we can easily run out of hugetlb pages during RAM migration and will crash (SIGBUS) instead of catching this gracefully via preallocation. Migrating device state via a vmsd before we start iterating is currently impossible: the only approach that would be possible is avoiding a vmsd and migrating state manually during save_setup(), to be restored during load_state(). Let's allow for migrating device state via a vmsd early, during the setup phase in qemu_savevm_state_setup(). To keep it simple, we indicate applicable vmds's using an "immutable" flag. Note that only very selected devices (i.e., ones seriously messing with RAM setup) are supposed to make use of such early state migration. Signed-off-by: David Hildenbrand --- include/migration/vmstate.h | 5 +++++ migration/savevm.c | 14 ++++++++++++++ 2 files changed, 19 insertions(+) diff --git a/include/migration/vmstate.h b/include/migration/vmstate.h index ad24aa1934..dd06c3abad 100644 --- a/include/migration/vmstate.h +++ b/include/migration/vmstate.h @@ -179,6 +179,11 @@ struct VMStateField { struct VMStateDescription { const char *name; int unmigratable; + /* + * The state is immutable while migration is active and is saved + * during the setup phase, to be restored early on the destination. + */ + int immutable; int version_id; int minimum_version_id; MigrationPriority priority; diff --git a/migration/savevm.c b/migration/savevm.c index ff2b8d0064..536d6f662b 100644 --- a/migration/savevm.c +++ b/migration/savevm.c @@ -1200,6 +1200,15 @@ void qemu_savevm_state_setup(QEMUFile *f) trace_savevm_state_setup(); QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { + if (se->vmsd && se->vmsd->immutable) { + ret = vmstate_save(f, se, ms->vmdesc); + if (ret) { + qemu_file_set_error(f, ret); + break; + } + continue; + } + if (!se->ops || !se->ops->save_setup) { continue; } @@ -1402,6 +1411,11 @@ int qemu_savevm_state_complete_precopy_non_iterable(QEMUFile *f, int ret; QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { + if (se->vmsd && se->vmsd->immutable) { + /* Already saved during qemu_savevm_state_setup(). */ + continue; + } + ret = vmstate_save(f, se, vmdesc); if (ret) { qemu_file_set_error(f, ret); From patchwork Thu Jan 12 16:43:59 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Hildenbrand X-Patchwork-Id: 13098446 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org 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 smtp.lore.kernel.org (Postfix) with ESMTPS id 18845C61DB3 for ; Thu, 12 Jan 2023 16:50:29 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1pG0gf-0004HX-V6; Thu, 12 Jan 2023 11:44:21 -0500 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 1pG0gd-0004G9-4e for qemu-devel@nongnu.org; Thu, 12 Jan 2023 11:44:20 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1pG0gb-0000du-LD for qemu-devel@nongnu.org; Thu, 12 Jan 2023 11:44:18 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1673541857; 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=NVLPn4mwhYR4iE04QX0aJFgiLkXDbx3Sr5+T2MvFIOA=; b=hja0/7yrDg43mTtQe4vneApRc7eREvVDULQy5E0peqhT5WStQPhxqjTku9w2otk+IiTM1H o6DO9mlNU2QwxlugB7p8cyvlyp2wSm8YNlz9OcMyC0NKJOK/iE0ECGXXLe4iqJgNIX4K0m /MZKivfagr3S5z5LPzEtnr7u2K2+zbw= Received: from mimecast-mx02.redhat.com (mx3-rdu2.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-360-ayvOr5vLOTe0K5wY3eqekg-1; Thu, 12 Jan 2023 11:44:15 -0500 X-MC-Unique: ayvOr5vLOTe0K5wY3eqekg-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.rdu2.redhat.com [10.11.54.2]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 719ED3C0D84D for ; Thu, 12 Jan 2023 16:44:15 +0000 (UTC) Received: from t480s.fritz.box (unknown [10.39.193.30]) by smtp.corp.redhat.com (Postfix) with ESMTP id 869584078903; Thu, 12 Jan 2023 16:44:13 +0000 (UTC) From: David Hildenbrand To: qemu-devel@nongnu.org Cc: David Hildenbrand , "Dr . David Alan Gilbert" , Juan Quintela , Peter Xu , "Michael S . Tsirkin" , Michal Privoznik Subject: [PATCH v3 4/8] migration/vmstate: Introduce VMSTATE_WITH_TMP_TEST() and VMSTATE_BITMAP_TEST() Date: Thu, 12 Jan 2023 17:43:59 +0100 Message-Id: <20230112164403.105085-5-david@redhat.com> In-Reply-To: <20230112164403.105085-1-david@redhat.com> References: <20230112164403.105085-1-david@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.2 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: -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_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: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org We'll make use of both next in the context of virtio-mem. Reviewed-by: Dr. David Alan Gilbert Signed-off-by: David Hildenbrand --- include/migration/vmstate.h | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) diff --git a/include/migration/vmstate.h b/include/migration/vmstate.h index dd06c3abad..e4cd21397d 100644 --- a/include/migration/vmstate.h +++ b/include/migration/vmstate.h @@ -710,8 +710,9 @@ extern const VMStateInfo vmstate_info_qlist; * '_state' type * That the pointer is right at the start of _tmp_type. */ -#define VMSTATE_WITH_TMP(_state, _tmp_type, _vmsd) { \ +#define VMSTATE_WITH_TMP_TEST(_state, _test, _tmp_type, _vmsd) { \ .name = "tmp", \ + .field_exists = (_test), \ .size = sizeof(_tmp_type) + \ QEMU_BUILD_BUG_ON_ZERO(offsetof(_tmp_type, parent) != 0) + \ type_check_pointer(_state, \ @@ -720,6 +721,9 @@ extern const VMStateInfo vmstate_info_qlist; .info = &vmstate_info_tmp, \ } +#define VMSTATE_WITH_TMP(_state, _tmp_type, _vmsd) \ + VMSTATE_WITH_TMP_TEST(_state, NULL, _tmp_type, _vmsd) + #define VMSTATE_UNUSED_BUFFER(_test, _version, _size) { \ .name = "unused", \ .field_exists = (_test), \ @@ -743,8 +747,9 @@ extern const VMStateInfo vmstate_info_qlist; /* _field_size should be a int32_t field in the _state struct giving the * size of the bitmap _field in bits. */ -#define VMSTATE_BITMAP(_field, _state, _version, _field_size) { \ +#define VMSTATE_BITMAP_TEST(_field, _state, _test, _version, _field_size) { \ .name = (stringify(_field)), \ + .field_exists = (_test), \ .version_id = (_version), \ .size_offset = vmstate_offset_value(_state, _field_size, int32_t),\ .info = &vmstate_info_bitmap, \ @@ -752,6 +757,9 @@ extern const VMStateInfo vmstate_info_qlist; .offset = offsetof(_state, _field), \ } +#define VMSTATE_BITMAP(_field, _state, _version, _field_size) \ + VMSTATE_BITMAP_TEST(_field, _state, NULL, _version, _field_size) + /* For migrating a QTAILQ. * Target QTAILQ needs be properly initialized. * _type: type of QTAILQ element From patchwork Thu Jan 12 16:44:00 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Hildenbrand X-Patchwork-Id: 13098444 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org 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 smtp.lore.kernel.org (Postfix) with ESMTPS id DC7FCC54EBD for ; Thu, 12 Jan 2023 16:47:06 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1pG0gj-0004Iz-2U; Thu, 12 Jan 2023 11:44:25 -0500 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 1pG0gf-0004HI-O9 for qemu-devel@nongnu.org; Thu, 12 Jan 2023 11:44:21 -0500 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 1pG0ge-0000eD-7C for qemu-devel@nongnu.org; Thu, 12 Jan 2023 11:44:21 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1673541859; 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=1fr6vZEWjOiuIoqkKICxG0tEOOGAmYLsqV4pK5w0WGo=; b=AT/GUuvJiPYbHvHzHMt9znua7HS5z3ivzKa7uSRLzJ2hgsAbhzzRAlvopN1TpcKDZdiKVW v4qfT81vBVuKGTpDc69QUAbdZisXHxIoiD7RFjhOGNGU1g50PDbqx8k48U9MQ9GD92OHBm 5wLekBz96w0pvgM3HkCus9qcdX57A68= Received: from mimecast-mx02.redhat.com (mx3-rdu2.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-519-9wfzhtezMSqlPKLfuj8PDQ-1; Thu, 12 Jan 2023 11:44:18 -0500 X-MC-Unique: 9wfzhtezMSqlPKLfuj8PDQ-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.rdu2.redhat.com [10.11.54.2]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id BB9323C0D84F for ; Thu, 12 Jan 2023 16:44:17 +0000 (UTC) Received: from t480s.fritz.box (unknown [10.39.193.30]) by smtp.corp.redhat.com (Postfix) with ESMTP id CA63E4078903; Thu, 12 Jan 2023 16:44:15 +0000 (UTC) From: David Hildenbrand To: qemu-devel@nongnu.org Cc: David Hildenbrand , "Dr . David Alan Gilbert" , Juan Quintela , Peter Xu , "Michael S . Tsirkin" , Michal Privoznik Subject: [PATCH v3 5/8] migration/ram: Factor out check for advised postcopy Date: Thu, 12 Jan 2023 17:44:00 +0100 Message-Id: <20230112164403.105085-6-david@redhat.com> In-Reply-To: <20230112164403.105085-1-david@redhat.com> References: <20230112164403.105085-1-david@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.2 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_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: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Let's factor out this check, to be used in virtio-mem context next. While at it, fix a spelling error in a related comment. Signed-off-by: David Hildenbrand Reviewed-by: Dr. David Alan Gilbert --- include/migration/misc.h | 4 +++- migration/migration.c | 7 +++++++ migration/ram.c | 8 +------- 3 files changed, 11 insertions(+), 8 deletions(-) diff --git a/include/migration/misc.h b/include/migration/misc.h index 465906710d..8b49841016 100644 --- a/include/migration/misc.h +++ b/include/migration/misc.h @@ -67,8 +67,10 @@ bool migration_has_failed(MigrationState *); /* ...and after the device transmission */ bool migration_in_postcopy_after_devices(MigrationState *); void migration_global_dump(Monitor *mon); -/* True if incomming migration entered POSTCOPY_INCOMING_DISCARD */ +/* True if incoming migration entered POSTCOPY_INCOMING_DISCARD */ bool migration_in_incoming_postcopy(void); +/* True if incoming migration entered POSTCOPY_INCOMING_ADVISE */ +bool migration_incoming_postcopy_advised(void); /* True if background snapshot is active */ bool migration_in_bg_snapshot(void); diff --git a/migration/migration.c b/migration/migration.c index 1d33a7efa0..b7677c14a9 100644 --- a/migration/migration.c +++ b/migration/migration.c @@ -2094,6 +2094,13 @@ bool migration_in_incoming_postcopy(void) return ps >= POSTCOPY_INCOMING_DISCARD && ps < POSTCOPY_INCOMING_END; } +bool migration_incoming_postcopy_advised(void) +{ + PostcopyState ps = postcopy_state_get(); + + return ps >= POSTCOPY_INCOMING_ADVISE && ps < POSTCOPY_INCOMING_END; +} + bool migration_in_bg_snapshot(void) { MigrationState *s = migrate_get_current(); diff --git a/migration/ram.c b/migration/ram.c index 334309f1c6..e51a7ee0ce 100644 --- a/migration/ram.c +++ b/migration/ram.c @@ -4091,12 +4091,6 @@ int ram_load_postcopy(QEMUFile *f, int channel) return ret; } -static bool postcopy_is_advised(void) -{ - PostcopyState ps = postcopy_state_get(); - return ps >= POSTCOPY_INCOMING_ADVISE && ps < POSTCOPY_INCOMING_END; -} - static bool postcopy_is_running(void) { PostcopyState ps = postcopy_state_get(); @@ -4167,7 +4161,7 @@ static int ram_load_precopy(QEMUFile *f) MigrationIncomingState *mis = migration_incoming_get_current(); int flags = 0, ret = 0, invalid_flags = 0, len = 0, i = 0; /* ADVISE is earlier, it shows the source has the postcopy capability on */ - bool postcopy_advised = postcopy_is_advised(); + bool postcopy_advised = migration_incoming_postcopy_advised(); if (!migrate_use_compression()) { invalid_flags |= RAM_SAVE_FLAG_COMPRESS_PAGE; } From patchwork Thu Jan 12 16:44:01 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Hildenbrand X-Patchwork-Id: 13098443 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org 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 smtp.lore.kernel.org (Postfix) with ESMTPS id 26EC7C54EBD for ; Thu, 12 Jan 2023 16:46:35 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1pG0gm-0004M5-4B; Thu, 12 Jan 2023 11:44:28 -0500 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 1pG0gh-0004IT-RK for qemu-devel@nongnu.org; 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Thu, 12 Jan 2023 11:44:20 -0500 X-MC-Unique: joZFcE3dMgG7aBBvcxQi6g-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.rdu2.redhat.com [10.11.54.2]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 26CB1811E6E for ; Thu, 12 Jan 2023 16:44:20 +0000 (UTC) Received: from t480s.fritz.box (unknown [10.39.193.30]) by smtp.corp.redhat.com (Postfix) with ESMTP id 330174078903; Thu, 12 Jan 2023 16:44:17 +0000 (UTC) From: David Hildenbrand To: qemu-devel@nongnu.org Cc: David Hildenbrand , "Dr . David Alan Gilbert" , Juan Quintela , Peter Xu , "Michael S . Tsirkin" , Michal Privoznik Subject: [PATCH v3 6/8] virtio-mem: Fail if a memory backend with "prealloc=on" is specified Date: Thu, 12 Jan 2023 17:44:01 +0100 Message-Id: <20230112164403.105085-7-david@redhat.com> In-Reply-To: <20230112164403.105085-1-david@redhat.com> References: <20230112164403.105085-1-david@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.2 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: -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_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: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org "prealloc=on" for the memory backend does not work as expected, as virtio-mem will simply discard all preallocated memory immediately again. In the best case, it's an expensive NOP. In the worst case, it's an unexpected allocation error. Instead, "prealloc=on" should be specified for the virtio-mem device only, such that virtio-mem will try preallocating memory before plugging memory dynamically to the guest. Fail if such a memory backend is provided. Tested-by: Michal Privoznik Signed-off-by: David Hildenbrand Reviewed-by: Dr. David Alan Gilbert --- hw/virtio/virtio-mem.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/hw/virtio/virtio-mem.c b/hw/virtio/virtio-mem.c index 1ed1f5a4af..02f7b5469a 100644 --- a/hw/virtio/virtio-mem.c +++ b/hw/virtio/virtio-mem.c @@ -772,6 +772,12 @@ static void virtio_mem_device_realize(DeviceState *dev, Error **errp) error_setg(errp, "'%s' property specifies an unsupported memdev", VIRTIO_MEM_MEMDEV_PROP); return; + } else if (vmem->memdev->prealloc) { + error_setg(errp, "'%s' property specifies a memdev with preallocation" + " enabled: %s. Instead, specify 'prealloc=on' for the" + " virtio-mem device. ", VIRTIO_MEM_MEMDEV_PROP, + object_get_canonical_path_component(OBJECT(vmem->memdev))); + return; } if ((nb_numa_nodes && vmem->node >= nb_numa_nodes) || From patchwork Thu Jan 12 16:44:02 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Hildenbrand X-Patchwork-Id: 13098379 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org 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 smtp.lore.kernel.org (Postfix) with ESMTPS id EB866C54EBC for ; Thu, 12 Jan 2023 16:45:25 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1pG0gn-0004Mg-4G; Thu, 12 Jan 2023 11:44:29 -0500 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 1pG0gk-0004LT-SB for qemu-devel@nongnu.org; Thu, 12 Jan 2023 11:44:26 -0500 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 1pG0gj-0000fQ-6w for qemu-devel@nongnu.org; Thu, 12 Jan 2023 11:44:26 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1673541864; 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=tuVG8JV+7c5if5wuQgRLkz9lzWotElbt8ZFW7yztIew=; b=QobkU69G+bpLjQcFYH9pYSWF2N7nfrrlWvq9FNQ2D0tebDjeerZ3dHoVWqp2oS8XdHBFgB /vyVcMh5+yaVVC5jqLOom9wv10ogfPDKW6SLM8QdDWloh+jLfOEwHcd7RA59Giq+KqYy+H JZ9xfug9FfezfNzDtBFxdrdh07sKgIc= 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-553-H1A3AcO9PbWJy9mgWJhWbw-1; Thu, 12 Jan 2023 11:44:22 -0500 X-MC-Unique: H1A3AcO9PbWJy9mgWJhWbw-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.rdu2.redhat.com [10.11.54.2]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 643BA882822 for ; Thu, 12 Jan 2023 16:44:22 +0000 (UTC) Received: from t480s.fritz.box (unknown [10.39.193.30]) by smtp.corp.redhat.com (Postfix) with ESMTP id 85EAA4078903; Thu, 12 Jan 2023 16:44:20 +0000 (UTC) From: David Hildenbrand To: qemu-devel@nongnu.org Cc: David Hildenbrand , "Dr . David Alan Gilbert" , Juan Quintela , Peter Xu , "Michael S . Tsirkin" , Michal Privoznik Subject: [PATCH v3 7/8] virtio-mem: Migrate immutable properties early Date: Thu, 12 Jan 2023 17:44:02 +0100 Message-Id: <20230112164403.105085-8-david@redhat.com> In-Reply-To: <20230112164403.105085-1-david@redhat.com> References: <20230112164403.105085-1-david@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.2 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_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: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org The bitmap and the size are immutable while migration is active: see virtio_mem_is_busy(). We can migrate this information early, before migrating any actual RAM content. Further, all information we need for sanity checks is immutable as well. Having this information in place early will, for example, allow for properly preallocating memory before touching these memory locations during RAM migration: this way, we can make sure that all memory was actually preallocated and that any user errors (e.g., insufficient hugetlb pages) can be handled gracefully. In contrast, usable_region_size and requested_size can theoretically still be modified on the source while the VM is running. Keep migrating these properties the usual, late, way. Use a new device property to keep behavior of compat machines unmodified. Signed-off-by: David Hildenbrand --- hw/core/machine.c | 4 ++- hw/virtio/virtio-mem.c | 51 ++++++++++++++++++++++++++++++++-- include/hw/virtio/virtio-mem.h | 8 ++++++ 3 files changed, 60 insertions(+), 3 deletions(-) diff --git a/hw/core/machine.c b/hw/core/machine.c index 616f3a207c..29b57f6448 100644 --- a/hw/core/machine.c +++ b/hw/core/machine.c @@ -41,7 +41,9 @@ #include "hw/virtio/virtio-pci.h" #include "qom/object_interfaces.h" -GlobalProperty hw_compat_7_2[] = {}; +GlobalProperty hw_compat_7_2[] = { + { "virtio-mem", "x-early-migration", "false" }, +}; const size_t hw_compat_7_2_len = G_N_ELEMENTS(hw_compat_7_2); GlobalProperty hw_compat_7_1[] = { diff --git a/hw/virtio/virtio-mem.c b/hw/virtio/virtio-mem.c index 02f7b5469a..51666baa01 100644 --- a/hw/virtio/virtio-mem.c +++ b/hw/virtio/virtio-mem.c @@ -31,6 +31,8 @@ #include CONFIG_DEVICES #include "trace.h" +static const VMStateDescription vmstate_virtio_mem_device_early; + /* * We only had legacy x86 guests that did not support * VIRTIO_MEM_F_UNPLUGGED_INACCESSIBLE. Other targets don't have legacy guests. @@ -878,6 +880,10 @@ 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)); + if (vmem->early_migration) { + vmstate_register(VMSTATE_IF(vmem), VMSTATE_INSTANCE_ID_ANY, + &vmstate_virtio_mem_device_early, vmem); + } qemu_register_reset(virtio_mem_system_reset, vmem); /* @@ -899,6 +905,10 @@ static void virtio_mem_device_unrealize(DeviceState *dev) */ memory_region_set_ram_discard_manager(&vmem->memdev->mr, NULL); qemu_unregister_reset(virtio_mem_system_reset, vmem); + if (vmem->early_migration) { + vmstate_unregister(VMSTATE_IF(vmem), &vmstate_virtio_mem_device_early, + vmem); + } vmstate_unregister_ram(&vmem->memdev->mr, DEVICE(vmem)); host_memory_backend_set_mapped(vmem->memdev, false); virtio_del_queue(vdev, 0); @@ -1015,18 +1025,53 @@ static const VMStateDescription vmstate_virtio_mem_sanity_checks = { }, }; +static bool virtio_mem_vmstate_field_exists(void *opaque, int version_id) +{ + const VirtIOMEM *vmem = VIRTIO_MEM(opaque); + + /* With early migration, these fields were already migrated. */ + return !vmem->early_migration; +} + static const VMStateDescription vmstate_virtio_mem_device = { .name = "virtio-mem-device", .minimum_version_id = 1, .version_id = 1, .priority = MIG_PRI_VIRTIO_MEM, .post_load = virtio_mem_post_load, + .fields = (VMStateField[]) { + VMSTATE_WITH_TMP_TEST(VirtIOMEM, virtio_mem_vmstate_field_exists, + VirtIOMEMMigSanityChecks, + vmstate_virtio_mem_sanity_checks), + VMSTATE_UINT64(usable_region_size, VirtIOMEM), + VMSTATE_UINT64_TEST(size, VirtIOMEM, virtio_mem_vmstate_field_exists), + VMSTATE_UINT64(requested_size, VirtIOMEM), + VMSTATE_BITMAP_TEST(bitmap, VirtIOMEM, virtio_mem_vmstate_field_exists, + 0, bitmap_size), + VMSTATE_END_OF_LIST() + }, +}; + +/* + * Transfer properties that are immutable while migration is active early, + * such that we have have this information around before migrating any RAM + * content. + * + * Note that virtio_mem_is_busy() makes sure these properties can no longer + * change on the migration source until migration completed. + * + * With QEMU compat machines, we transmit these properties later, via + * vmstate_virtio_mem_device instead -- see virtio_mem_vmstate_field_exists(). + */ +static const VMStateDescription vmstate_virtio_mem_device_early = { + .name = "virtio-mem-device-early", + .minimum_version_id = 1, + .version_id = 1, + .immutable = 1, .fields = (VMStateField[]) { VMSTATE_WITH_TMP(VirtIOMEM, VirtIOMEMMigSanityChecks, vmstate_virtio_mem_sanity_checks), - VMSTATE_UINT64(usable_region_size, VirtIOMEM), VMSTATE_UINT64(size, VirtIOMEM), - VMSTATE_UINT64(requested_size, VirtIOMEM), VMSTATE_BITMAP(bitmap, VirtIOMEM, 0, bitmap_size), VMSTATE_END_OF_LIST() }, @@ -1211,6 +1256,8 @@ static Property virtio_mem_properties[] = { DEFINE_PROP_ON_OFF_AUTO(VIRTIO_MEM_UNPLUGGED_INACCESSIBLE_PROP, VirtIOMEM, unplugged_inaccessible, ON_OFF_AUTO_AUTO), #endif + DEFINE_PROP_BOOL(VIRTIO_MEM_EARLY_MIGRATION_PROP, VirtIOMEM, + early_migration, true), DEFINE_PROP_END_OF_LIST(), }; diff --git a/include/hw/virtio/virtio-mem.h b/include/hw/virtio/virtio-mem.h index 7745cfc1a3..f15e561785 100644 --- a/include/hw/virtio/virtio-mem.h +++ b/include/hw/virtio/virtio-mem.h @@ -31,6 +31,7 @@ OBJECT_DECLARE_TYPE(VirtIOMEM, VirtIOMEMClass, #define VIRTIO_MEM_BLOCK_SIZE_PROP "block-size" #define VIRTIO_MEM_ADDR_PROP "memaddr" #define VIRTIO_MEM_UNPLUGGED_INACCESSIBLE_PROP "unplugged-inaccessible" +#define VIRTIO_MEM_EARLY_MIGRATION_PROP "x-early-migration" #define VIRTIO_MEM_PREALLOC_PROP "prealloc" struct VirtIOMEM { @@ -74,6 +75,13 @@ struct VirtIOMEM { /* whether to prealloc memory when plugging new blocks */ bool prealloc; + /* + * Whether we migrate properties that are immutable while migration is + * active early, before state of other devices and especially, before + * migrating any RAM content. + */ + bool early_migration; + /* notifiers to notify when "size" changes */ NotifierList size_change_notifiers; From patchwork Thu Jan 12 16:44:03 2023 Content-Type: text/plain; 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Thu, 12 Jan 2023 16:44:24 +0000 (UTC) Received: from t480s.fritz.box (unknown [10.39.193.30]) by smtp.corp.redhat.com (Postfix) with ESMTP id C70A74078903; Thu, 12 Jan 2023 16:44:22 +0000 (UTC) From: David Hildenbrand To: qemu-devel@nongnu.org Cc: David Hildenbrand , "Dr . David Alan Gilbert" , Juan Quintela , Peter Xu , "Michael S . Tsirkin" , Michal Privoznik , Jing Qi Subject: [PATCH v3 8/8] virtio-mem: Proper support for preallocation with migration Date: Thu, 12 Jan 2023 17:44:03 +0100 Message-Id: <20230112164403.105085-9-david@redhat.com> In-Reply-To: <20230112164403.105085-1-david@redhat.com> References: <20230112164403.105085-1-david@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.2 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: -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_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: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Ordinary memory preallocation runs when QEMU starts up and creates the memory backends, before processing the incoming migration stream. With virtio-mem, we don't know which memory blocks to preallocate before migration started. Now that we migrate the virtio-mem bitmap early, before migrating any RAM content, we can safely preallocate memory for all plugged memory blocks before migrating any RAM content. This is especially relevant for the following cases: (1) User errors With hugetlb/files, if we don't have sufficient backend memory available on the migration destination, we'll crash QEMU (SIGBUS) during RAM migration when running out of backend memory. Preallocating memory before actual RAM migration allows for failing gracefully and informing the user about the setup problem. (2) Excluded memory ranges during migration For example, virtio-balloon free page hinting will exclude some pages from getting migrated. In that case, we won't crash during RAM migration, but later, when running the VM on the destination, which is bad. To fix this for new QEMU machines that migrate the bitmap early, preallocate the memory early, before any RAM migration. Warn with old QEMU machines. Getting postcopy right is a bit tricky, but we essentially now implement the same (problematic) preallocation logic as ordinary preallocation: preallocate memory early and discard it again before precopy starts. During ordinary preallocation, discarding of RAM happens when postcopy is advised. As the state (bitmap) is loaded after postcopy was advised but before postcopy starts listening, we have to discard memory we preallocated immediately again ourselves. Note that nothing (not even hugetlb reservations) guarantees for postcopy that backend memory (especially, hugetlb pages) are still free after they were freed ones while discarding RAM. Still, allocating that memory at least once helps catching some basic setup problems. Before this change, trying to restore a VM when insufficient hugetlb pages are around results in the process crashing to to a "Bus error" (SIGBUS). With this change, QEMU fails gracefully: qemu-system-x86_64: qemu_prealloc_mem: preallocating memory failed: Bad address qemu-system-x86_64: error while loading state for instance 0x0 of device '0000:00:03.0/virtio-mem-device-early' qemu-system-x86_64: load of migration failed: Cannot allocate memory And we can even introspect the early migration data, including the bitmap: $ ./scripts/analyze-migration.py -f STATEFILE { "ram (2)": { "section sizes": { "0000:00:03.0/mem0": "0x0000000780000000", "0000:00:04.0/mem1": "0x0000000780000000", "pc.ram": "0x0000000100000000", "/rom@etc/acpi/tables": "0x0000000000020000", "pc.bios": "0x0000000000040000", "0000:00:02.0/e1000.rom": "0x0000000000040000", "pc.rom": "0x0000000000020000", "/rom@etc/table-loader": "0x0000000000001000", "/rom@etc/acpi/rsdp": "0x0000000000001000" } }, "0000:00:03.0/virtio-mem-device-early (51)": { "tmp": "00 00 00 01 40 00 00 00 00 00 00 07 80 00 00 00 00 00 00 00 00 20 00 00 00 00 00 00", "size": "0x0000000040000000", "bitmap": "ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff [...] }, "0000:00:04.0/virtio-mem-device-early (53)": { "tmp": "00 00 00 08 c0 00 00 00 00 00 00 07 80 00 00 00 00 00 00 00 00 20 00 00 00 00 00 00", "size": "0x00000001fa400000", "bitmap": "ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff [...] }, [...] Reported-by: Jing Qi Signed-off-by: David Hildenbrand Reviewed-by: Dr. David Alan Gilbert --- hw/virtio/virtio-mem.c | 87 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 87 insertions(+) diff --git a/hw/virtio/virtio-mem.c b/hw/virtio/virtio-mem.c index 51666baa01..4c3720249c 100644 --- a/hw/virtio/virtio-mem.c +++ b/hw/virtio/virtio-mem.c @@ -204,6 +204,30 @@ static int virtio_mem_for_each_unplugged_range(const VirtIOMEM *vmem, void *arg, return ret; } +static int virtio_mem_for_each_plugged_range(const VirtIOMEM *vmem, void *arg, + virtio_mem_range_cb cb) +{ + unsigned long first_bit, last_bit; + uint64_t offset, size; + int ret = 0; + + first_bit = find_first_bit(vmem->bitmap, vmem->bitmap_size); + while (first_bit < vmem->bitmap_size) { + offset = first_bit * vmem->block_size; + last_bit = find_next_zero_bit(vmem->bitmap, vmem->bitmap_size, + first_bit + 1) - 1; + size = (last_bit - first_bit + 1) * vmem->block_size; + + ret = cb(vmem, arg, offset, size); + if (ret) { + break; + } + first_bit = find_next_bit(vmem->bitmap, vmem->bitmap_size, + last_bit + 2); + } + return ret; +} + /* * Adjust the memory section to cover the intersection with the given range. * @@ -938,6 +962,10 @@ static int virtio_mem_post_load(void *opaque, int version_id) RamDiscardListener *rdl; int ret; + if (vmem->prealloc && !vmem->early_migration) { + warn_report("Proper preallocation with migration requires a newer QEMU machine"); + } + /* * We started out with all memory discarded and our memory region is mapped * into an address space. Replay, now that we updated the bitmap. @@ -957,6 +985,64 @@ static int virtio_mem_post_load(void *opaque, int version_id) return virtio_mem_restore_unplugged(vmem); } +static int virtio_mem_prealloc_range_cb(const VirtIOMEM *vmem, void *arg, + uint64_t offset, uint64_t size) +{ + void *area = memory_region_get_ram_ptr(&vmem->memdev->mr) + offset; + int fd = memory_region_get_fd(&vmem->memdev->mr); + Error *local_err = NULL; + + qemu_prealloc_mem(fd, area, size, 1, NULL, &local_err); + if (local_err) { + error_report_err(local_err); + return -ENOMEM; + } + return 0; +} + +static int virtio_mem_post_load_early(void *opaque, int version_id) +{ + VirtIOMEM *vmem = VIRTIO_MEM(opaque); + RAMBlock *rb = vmem->memdev->mr.ram_block; + int ret; + + if (!vmem->prealloc) { + return 0; + } + + /* + * We restored the bitmap and verified that the basic properties + * match on source and destination, so we can go ahead and preallocate + * memory for all plugged memory blocks, before actual RAM migration starts + * touching this memory. + */ + ret = virtio_mem_for_each_plugged_range(vmem, NULL, + virtio_mem_prealloc_range_cb); + if (ret) { + return ret; + } + + /* + * This is tricky: postcopy wants to start with a clean slate. On + * POSTCOPY_INCOMING_ADVISE, postcopy code discards all (ordinarily + * preallocated) RAM such that postcopy will work as expected later. + * + * However, we run after POSTCOPY_INCOMING_ADVISE -- but before actual + * RAM migration. So let's discard all memory again. This looks like an + * expensive NOP, but actually serves a purpose: we made sure that we + * were able to allocate all required backend memory once. We cannot + * guarantee that the backend memory we will free will remain free + * until we need it during postcopy, but at least we can catch the + * obvious setup issues this way. + */ + if (migration_incoming_postcopy_advised()) { + if (ram_block_discard_range(rb, 0, qemu_ram_get_used_length(rb))) { + return -EBUSY; + } + } + return 0; +} + typedef struct VirtIOMEMMigSanityChecks { VirtIOMEM *parent; uint64_t addr; @@ -1068,6 +1154,7 @@ static const VMStateDescription vmstate_virtio_mem_device_early = { .minimum_version_id = 1, .version_id = 1, .immutable = 1, + .post_load = virtio_mem_post_load_early, .fields = (VMStateField[]) { VMSTATE_WITH_TMP(VirtIOMEM, VirtIOMEMMigSanityChecks, vmstate_virtio_mem_sanity_checks),