From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists1p.gnu.org (lists1p.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 E3EB7CD8CB2 for ; Wed, 10 Jun 2026 16:20:00 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists1p.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1wXLZD-0005IC-9P; Wed, 10 Jun 2026 12:14:11 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists1p.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1wXLZC-0005FW-0s for qemu-devel@nongnu.org; Wed, 10 Jun 2026 12:14:10 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1wXLZ9-00078e-1d for qemu-devel@nongnu.org; Wed, 10 Jun 2026 12:14:09 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1781108046; h=from:from:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:in-reply-to:in-reply-to: references:references; bh=5UaEU4+BaDuPjrl/JW705Nct5RnzLpt0GzsvI6jg94M=; b=MojtmjVQaDzMT5VwuALADQXlDR8Tz/Rgasd3tsTPS1/o1tGN48FL0Cie3uxAdth4mQOT1L 1pt178G8MC7qnu7xKDvA9I739wjep9oGgP48X6+n7mwkxkvEmjcTUzk/ACsKHsO3a1uHO9 iugIVvpZL4YEssAx7SeZZ2oq+3wraCk= Received: from mx-prod-mc-01.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-553-GHe8yqeRP0i8KVAetRAU8g-1; Wed, 10 Jun 2026 12:14:00 -0400 X-MC-Unique: GHe8yqeRP0i8KVAetRAU8g-1 X-Mimecast-MFC-AGG-ID: GHe8yqeRP0i8KVAetRAU8g_1781108039 Received: from mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.17]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-01.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 2CF41195FDE9; Wed, 10 Jun 2026 16:13:58 +0000 (UTC) Received: from redhat.com (unknown [10.44.50.112]) by mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 45FBF1954102; Wed, 10 Jun 2026 16:13:50 +0000 (UTC) Date: Wed, 10 Jun 2026 17:13:47 +0100 From: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= To: Peter Xu Cc: qemu-devel@nongnu.org, qemu-arm@nongnu.org, =?utf-8?Q?C=C3=A9dric?= Le Goater , Philippe =?utf-8?Q?Mathieu-Daud=C3=A9?= , Fabiano Rosas , Vladimir Sementsov-Ogievskiy , Peter Maydell , "Dr . David Alan Gilbert" , Eric Blake , Akihiko Odaki , Paolo Bonzini , Kevin Wolf , Sana Sharma , =?utf-8?Q?Marc-Andr=C3=A9?= Lureau , Juraj Marcin , qemu-rust@nongnu.org, Markus Armbruster , Mark Cave-Ayland Subject: Re: [PATCH v2 10/10] migration: Switch to TYPE_OBJECT with object properties Message-ID: References: <20260609172514.2037645-1-peterx@redhat.com> <20260609172514.2037645-11-peterx@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20260609172514.2037645-11-peterx@redhat.com> User-Agent: Mutt/2.3.2 (2026-04-26) X-Scanned-By: MIMEDefang 3.0 on 10.30.177.17 Received-SPF: pass client-ip=170.10.129.124; envelope-from=berrange@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -24 X-Spam_score: -2.5 X-Spam_bar: -- X-Spam_report: (-2.5 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.445, 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_H3=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001 autolearn=unavailable autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: qemu development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org On Tue, Jun 09, 2026 at 01:25:14PM -0400, Peter Xu wrote: > The migration object used to depend on TYPE_DEVICE due to: > > - Usage of qdev properties > - Apply compat properties and global properties > > This patch re-based the object to TYPE_OBJECT with the changes: > > - Switch to object properties API > - Manually apply both compat and global properties in post_init() > > Note that to avoid too many property getter/setter helpers, this patch used > the object_property_add_*_ptr_def() APIs so that an pointer is passed to > bind to the property. Such API is used for most of the conversions. > > After patch, the migration object initializes instance properties within > its instance_init() callback, in migrate_params_init(). > > One side effect of this change is, since we switched to a loop to add all > capabilities, the name of the properties representing a migration > capability may chance from previously hard-coded ones (many with x-). It's > fine since it's only used in -global so it's only for debugging. > > Similarly, I removed "x-" from other properites that used to start with > "x-" but actually are not experimental. Mixing such a change into a refactoring commit is bad practice, can you keep property changes separated. > After the whole conversion, we don't need migration_properties or the count > anymore, hence can be removed. While at it, we can also remove two > DEFINE_PROP*() API that only migration uses (DEFINE_PROP_STR_OR_NULL, and > DEFINE_PROP_MIG_CAP). > > Signed-off-by: Peter Xu > --- > migration/options.h | 8 +- > migration/migration.c | 35 ++- > migration/options.c | 526 ++++++++++++++++++++++++++---------------- > 3 files changed, 351 insertions(+), 218 deletions(-) > diff --git a/migration/options.c b/migration/options.c > index 5cbfd29099..1cc99382d3 100644 > --- a/migration/options.c > +++ b/migration/options.c > @@ -54,7 +54,7 @@ > +static void migration_object_init_props_bool(MigrationState *s) > { > - const Property *prop = opaque; > - StrOrNull **ptr = object_field_prop_ptr(obj, prop); > - StrOrNull *str_or_null = *ptr; > + Object *obj = OBJECT(s); > + int i; > > - /* > - * The property should never be NULL because it's part of > - * s->parameters and a default value is always set by qdev. It > - * should also never be QNULL as the setter doesn't allow it. > - */ > - assert(str_or_null && str_or_null->type != QTYPE_QNULL); > - visit_type_str(v, name, &str_or_null->u.s, errp); > + struct MigPropBool { > + const char *name; > + void *ptr; > + bool defvar; > + } bool_list[] = { > + { > + "store-global-state", > + &s->store_global_state, > + true, > + }, > + { > + "send-configuration", > + &s->send_configuration, > + true, > + }, > + { > + "send-section-footer", > + &s->send_section_footer, > + true, > + }, > + { > + "send-switchover-start", > + &s->send_switchover_start, > + true, > + }, > + { > + "x-preempt-pre-7-2", > + &s->preempt_pre_7_2, > + false, > + }, > + { > + "x-cpu-throttle-tailslow", > + &s->parameters.cpu_throttle_tailslow, > + false, > + }, > + { > + "multifd-clean-tls-termination", > + &s->multifd_clean_tls_termination, > + true, > + }, > + { > + "multifd-flush-after-each-section", > + &s->multifd_flush_after_each_section, > + false, > + }, > + }; > + struct MigPropBool *prop; This approach to declaring properties is pretty unpleasant to follow IMHO. Being a custom different approach from every other object impl is not a good thing. > + > + for (i = 0; i < ARRAY_SIZE(bool_list); i++) { > + prop = &bool_list[i]; > + object_property_add_bool_ptr_def(obj, prop->name, > + prop->ptr, prop->defvar); > + } Using instance level properties is the old way to do things, it is preferred to use class level properties instead. This means you can't use the "ptr" concept to directly reference the instance fields and have to provide setters / getters explicitly instead, but as you've shown with the TLS properties, a macro can make it simple to define the repetitive getters/setters. > +static void migration_object_init_props_enum(MigrationState *s) > +{ > + Object *obj = OBJECT(s); > + ObjectProperty *prop; > + > + prop = object_property_add_enum(obj, "multifd-compression", > + "MultiFDCompression", > + &MultiFDCompression_lookup, > + mig_prop_multifd_compression_get, > + mig_prop_multifd_compression_set); > + object_property_set_default_str(prop, DEFAULT_MIGRATE_MULTIFD_COMPRESSION); > + > + prop = object_property_add_enum(obj, "mode", "MigMode", &MigMode_lookup, > + mig_prop_mode_get, mig_prop_mode_set); > + object_property_set_default_str(prop, "normal"); > + > + prop = object_property_add_enum(obj, "zero-page-detection", > + "ZeroPageDetection", > + &ZeroPageDetection_lookup, > + mig_prop_zero_page_detection_get, > + mig_prop_zero_page_detection_set); > + object_property_set_default_str(prop, "multifd"); > +} Perhaps I'm missing something, but I'm not seeing the point in using the set_default methods - in fact I'm not really sure why they exist in QOM at all. I'd expect all defaults to be set in the instance _init method. ie why isn't this done as: void migrate_params_init(MigrationState *s) { s->parameters.mode = MIG_MODE_NORMAL; s->parameters.zero_page_detection = ZERO_PAGE_DETECTION_MULTIFD; .... all other defaults... } > + > +static void migration_object_init_properties(MigrationState *s) > +{ > + migration_object_init_props_bool(s); > + migration_object_init_props_uint8(s); > + migration_object_init_props_uint32(s); > + migration_object_init_props_uint64(s); > + migration_object_init_props_size(s); > + migration_object_init_props_caps(s); > + migration_object_init_props_tls(s); > + migration_object_init_props_enum(s); > +} ...and class properties be registered in migrate_params_class_init() and the grouping per type isn't helpful IMHO, just put all the object_class_property_add calls inline in one place. > > bool migrate_auto_converge(void) > { > @@ -1107,9 +1246,10 @@ MigrationParameters *qmp_query_migrate_parameters(Error **errp) > return params; > } > > -void migrate_params_init(MigrationParameters *params) > +void migrate_params_init(MigrationState *s) > { > - migrate_mark_all_params_present(params); > + migration_object_init_properties(s); > + migrate_mark_all_params_present(&s->parameters); > } > > static void migrate_post_update_params(MigrationParameters *new, Error **errp) > -- > 2.53.0 > With regards, Daniel -- |: https://berrange.com ~~ https://hachyderm.io/@berrange :| |: https://libvirt.org ~~ https://entangle-photo.org :| |: https://pixelfed.art/berrange ~~ https://fstop138.berrange.com :|