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 B971BC43458 for ; Fri, 3 Jul 2026 12:48:49 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists1p.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1wfdJn-00028d-Dj; Fri, 03 Jul 2026 08:48:31 -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 1wfdJh-00021u-6D for qemu-devel@nongnu.org; Fri, 03 Jul 2026 08:48:26 -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 1wfdJe-00065T-NC for qemu-devel@nongnu.org; Fri, 03 Jul 2026 08:48:24 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1783082901; 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=wSKE0kCaaJqtzMyQQhIsIx2kt4BzhMJHyOU896FW/P4=; b=MFpsVHPHdn+Yx85/4ylXL2VhUVNzaTU7uTwS3Qhnq2nofLe0Z/CRXHUNOBOWRSXl7Wp1wI SazO/5vfgeoWw26wbESCoplU/Ol4q0QqHy2+quDmLbJ056AtxjsmjSKETDQM+7HF76XHMh rJstHFdeUpYhcduL7/WeGBYXlQIbM1E= Received: from mx-prod-mc-05.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-55-IIl8emJ5PvySPOZC-zecQw-1; Fri, 03 Jul 2026 08:48:20 -0400 X-MC-Unique: IIl8emJ5PvySPOZC-zecQw-1 X-Mimecast-MFC-AGG-ID: IIl8emJ5PvySPOZC-zecQw_1783082898 Received: from mx-prod-int-10.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-10.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.95]) (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-05.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 9AC1B1921EF3; Fri, 3 Jul 2026 12:48:18 +0000 (UTC) Received: from blackfin.pond.sub.org (unknown [10.44.22.4]) by mx-prod-int-10.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 60AC436F24; Fri, 3 Jul 2026 12:48:17 +0000 (UTC) Received: by blackfin.pond.sub.org (Postfix, from userid 1000) id EE86721E6920; Fri, 03 Jul 2026 14:48:14 +0200 (CEST) From: Markus Armbruster To: Daniel P. =?utf-8?Q?Berrang=C3=A9?= Cc: qemu-devel@nongnu.org, Paolo Bonzini , "Dr. David Alan Gilbert" , =?utf-8?Q?Marc-Andr=C3=A9?= Lureau , Alex =?utf-8?Q?Benn=C3=A9e?= , Philippe =?utf-8?Q?Mathieu-Daud=C3=A9?= , Christian Brauner , devel@lists.libvirt.org Subject: Re: [PATCH v6 05/34] monitor: minimal conversion of monitors to QOM In-Reply-To: <20260702160337.1910921-6-berrange@redhat.com> ("Daniel P. =?utf-8?Q?Berrang=C3=A9=22's?= message of "Thu, 2 Jul 2026 17:03:08 +0100") References: <20260702160337.1910921-1-berrange@redhat.com> <20260702160337.1910921-6-berrange@redhat.com> Date: Fri, 03 Jul 2026 14:48:14 +0200 Message-ID: <87echkw86p.fsf@pond.sub.org> User-Agent: Gnus/5.13 (Gnus v5.13) MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable X-Scanned-By: MIMEDefang 3.6 on 10.30.177.95 Received-SPF: pass client-ip=170.10.129.124; envelope-from=armbru@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: 8 X-Spam_score: 0.8 X-Spam_bar: / X-Spam_report: (0.8 / 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, RCVD_IN_SBL_CSS=3.335, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001 autolearn=no 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: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Daniel P. Berrang=C3=A9 writes: > This introduces a Monitor QOM object, with MonitorHMP and > MonitorQMP subclasses. This is the bare minimum conversion > of just the type declarations and replacing g_new/g_free > with object_new/object_unref. The Monitor base class is > abstract since only the HMP/QMP variants should ever be > created. > > When created through the existing QemuOpts interfaces, the > new internal QOM object will get assigned a dynamic ID with > the format "compat_monitorNNN" which is the historical > QemuOpts ID naming pattern. > > Signed-off-by: Daniel P. Berrang=C3=A9 > --- > chardev/char.c | 2 +- > gdbstub/system.c | 2 +- > include/monitor/monitor.h | 18 +++++++++++++++--- > monitor/hmp.c | 31 ++++++++++++++++++++++++++++--- > monitor/monitor-internal.h | 18 ++++++++++++++++-- > monitor/monitor.c | 31 +++++++++++++++++++++++++++---- > monitor/qmp-cmds.c | 15 ++++++++------- > monitor/qmp.c | 31 ++++++++++++++++++++++++++++--- > stubs/monitor-internal.c | 3 ++- > system/vl.c | 7 +++---- > 10 files changed, 129 insertions(+), 29 deletions(-) > > diff --git a/chardev/char.c b/chardev/char.c > index 813c04d953..c71ffa7963 100644 > --- a/chardev/char.c > +++ b/chardev/char.c > @@ -805,7 +805,7 @@ static Chardev *qemu_chr_new_from_name(const char *la= bel, const char *filename, >=20=20 > if (qemu_opt_get_bool(opts, "mux", 0)) { > assert(permit_mux_mon); > - monitor_new_hmp(chr, true, &err); > + monitor_new_hmp(NULL, chr, true, &err); Yet another way to create a monitor, not covered by the commit message. We get here for legacy chardev syntax "mon:...", I think. Where exactly in the external interface this is accepted I'm not sure. It's documented for -serial. See qemu-options.hx. There is no "mon" QemuOpts. You pass NULL to monitor_new_hmp(), which makes it create the object as /objects/compat_monitorNNN. > if (err) { > error_report_err(err); > object_unparent(OBJECT(chr)); > diff --git a/gdbstub/system.c b/gdbstub/system.c > index 18f6a62b2e..fda8ef9352 100644 > --- a/gdbstub/system.c > +++ b/gdbstub/system.c > @@ -389,7 +389,7 @@ bool gdbserver_start(const char *device, Error **errp) > /* Initialize a monitor terminal for gdb */ > mon_chr =3D qemu_chardev_new(NULL, TYPE_CHARDEV_GDB, > NULL, NULL, &error_abort); > - monitor_new_hmp(mon_chr, false, &error_abort); > + monitor_new_hmp(NULL, mon_chr, false, &error_abort); And yet another, also no "mon" QemuOpts, and also /objects/compat_monitorNNN. > } else { > qemu_chr_fe_deinit(&gdbserver_system_state.chr, true); > mon_chr =3D gdbserver_system_state.mon_chr; > diff --git a/include/monitor/monitor.h b/include/monitor/monitor.h > index b9642b58ba..83723f705a 100644 > --- a/include/monitor/monitor.h > +++ b/include/monitor/monitor.h > @@ -5,8 +5,17 @@ > #include "qapi/qapi-types-misc.h" > #include "qemu/readline.h" > #include "exec/hwaddr.h" > +#include "qom/object.h" > + > +#define TYPE_MONITOR "monitor" > +OBJECT_DECLARE_TYPE(Monitor, MonitorClass, MONITOR); > + > +#define TYPE_MONITOR_HMP "monitor-hmp" > +OBJECT_DECLARE_TYPE(MonitorHMP, MonitorHMPClass, MONITOR_HMP); > + > +#define TYPE_MONITOR_QMP "monitor-qmp" > +OBJECT_DECLARE_TYPE(MonitorQMP, MonitorQMPClass, MONITOR_QMP); >=20=20 > -typedef struct MonitorHMP MonitorHMP; > typedef struct MonitorOptions MonitorOptions; >=20=20 > #define QMP_REQ_QUEUE_LEN_MAX 8 > @@ -19,8 +28,11 @@ bool monitor_cur_is_qmp(void); >=20=20 > void monitor_init_globals(void); > void monitor_init_globals_core(void); > -void monitor_new_qmp(Chardev *chr, bool pretty, Error **errp); > -void monitor_new_hmp(Chardev *chr, bool use_readline, Error **errp); > +char *monitor_compat_id(void); > +void monitor_new_qmp(const char *id, Chardev *chr, > + bool pretty, Error **errp); > +void monitor_new_hmp(const char *id, Chardev *chr, > + bool use_readline, Error **errp); > int monitor_new(MonitorOptions *opts, bool allow_hmp, Error **errp); > int monitor_new_opts(QemuOpts *opts, Error **errp); > void monitor_cleanup(void); > diff --git a/monitor/hmp.c b/monitor/hmp.c > index 4e4468424a..da11e56854 100644 > --- a/monitor/hmp.c > +++ b/monitor/hmp.c > @@ -43,6 +43,20 @@ > #include "system/block-backend.h" > #include "trace.h" >=20=20 > +OBJECT_DEFINE_TYPE(MonitorHMP, monitor_hmp, MONITOR_HMP, MONITOR); > + > +static void monitor_hmp_finalize(Object *obj) > +{ > +} > + > +static void monitor_hmp_class_init(ObjectClass *cls, const void *data) > +{ > +} > + > +static void monitor_hmp_init(Object *obj) > +{ > +} > + > static void monitor_command_cb(void *opaque, const char *cmdline, > void *readline_opaque) > { > @@ -1524,12 +1538,23 @@ static void monitor_readline_flush(void *opaque) > monitor_flush(&mon->parent_obj); > } >=20=20 > -void monitor_new_hmp(Chardev *chr, bool use_readline, Error **errp) > +void monitor_new_hmp(const char *id, Chardev *chr, > + bool use_readline, Error **errp) > { > - MonitorHMP *mon =3D g_new0(MonitorHMP, 1); > + MonitorHMP *mon; > + g_autofree char *autoid =3D id ? NULL : monitor_compat_id(); > + Object *obj =3D object_new_with_props(TYPE_MONITOR_HMP, > + object_get_objects_root(), > + id ? id : autoid, > + errp, > + NULL); > + if (!obj) { > + return; > + } > + mon =3D MONITOR_HMP(obj); >=20=20 > if (!qemu_chr_fe_init(&mon->parent_obj.chr, chr, errp)) { > - g_free(mon); > + object_unparent(OBJECT(mon)); > return; > } >=20=20 > diff --git a/monitor/monitor-internal.h b/monitor/monitor-internal.h > index 4da2b2a677..05c1f2f5e0 100644 > --- a/monitor/monitor-internal.h > +++ b/monitor/monitor-internal.h > @@ -101,7 +101,13 @@ typedef struct HMPCommand { > bool coroutine; > } HMPCommand; >=20=20 > + > +struct MonitorClass { > + ObjectClass parent_class; > +}; > + > struct Monitor { > + Object parent; > CharFrontend chr; > int suspend_cnt; /* Needs to be accessed atomically */ > bool is_qmp; > @@ -127,6 +133,10 @@ struct Monitor { > int reset_seen; > }; >=20=20 > +struct MonitorHMPClass { > + MonitorClass parent_class; > +}; > + > struct MonitorHMP { > Monitor parent_obj; > bool use_readline; > @@ -140,7 +150,11 @@ struct MonitorHMP { > ReadLineState *rs; > }; >=20=20 > -typedef struct { > +struct MonitorQMPClass { > + MonitorClass parent_class; > +}; > + > +struct MonitorQMP { > Monitor parent_obj; > JSONMessageParser parser; > bool pretty; > @@ -160,7 +174,7 @@ typedef struct { > QemuMutex qmp_queue_lock; > /* Input queue that holds all the parsed QMP requests */ > GQueue *qmp_requests; > -} MonitorQMP; > +}; >=20=20 > /** > * Is @mon a QMP monitor? > diff --git a/monitor/monitor.c b/monitor/monitor.c > index a87597e606..18a1d8ddde 100644 > --- a/monitor/monitor.c > +++ b/monitor/monitor.c > @@ -73,6 +73,22 @@ static GHashTable *coroutine_mon; /* Maps Coroutine* t= o Monitor* */ > MonitorList mon_list; > static bool monitor_destroyed; >=20=20 > +int monitor_device_index; > + > +OBJECT_DEFINE_ABSTRACT_TYPE(Monitor, monitor, MONITOR, OBJECT); > + > +static void monitor_finalize(Object *obj) > +{ > +} > + > +static void monitor_class_init(ObjectClass *cls, const void *data) > +{ > +} > + > +static void monitor_init(Object *obj) > +{ > +} > + > Monitor *monitor_cur(void) > { > Monitor *mon; > @@ -598,7 +614,7 @@ void monitor_list_append(Monitor *mon) >=20=20 > if (mon) { > monitor_data_destroy(mon); > - g_free(mon); > + object_unparent(OBJECT(mon)); > } > } >=20=20 > @@ -680,7 +696,7 @@ void monitor_cleanup(void) > monitor_flush(mon); > monitor_data_destroy(mon); > qemu_mutex_lock(&monitor_lock); > - g_free(mon); > + object_unparent(OBJECT(mon)); > } > qemu_mutex_unlock(&monitor_lock); >=20=20 > @@ -715,6 +731,13 @@ void monitor_init_globals(void) > aio_co_schedule(iohandler_get_aio_context(), qmp_dispatcher_co); > } >=20=20 > +char *monitor_compat_id(void) > +{ > + static int monitor_device_index; > + > + return g_strdup_printf("compat_monitor%d", monitor_device_index++); > +} > + > int monitor_new(MonitorOptions *opts, bool allow_hmp, Error **errp) > { > ERRP_GUARD(); > @@ -732,7 +755,7 @@ int monitor_new(MonitorOptions *opts, bool allow_hmp,= Error **errp) >=20=20 > switch (opts->mode) { > case MONITOR_MODE_CONTROL: > - monitor_new_qmp(chr, opts->pretty, errp); > + monitor_new_qmp(opts->id, chr, opts->pretty, errp); > break; > case MONITOR_MODE_READLINE: > if (!allow_hmp) { > @@ -743,7 +766,7 @@ int monitor_new(MonitorOptions *opts, bool allow_hmp,= Error **errp) > error_setg(errp, "'pretty' is not compatible with HMP monito= rs"); > return -1; > } > - monitor_new_hmp(chr, true, errp); > + monitor_new_hmp(opts->id, chr, true, errp); > break; > default: > g_assert_not_reached(); > diff --git a/monitor/qmp-cmds.c b/monitor/qmp-cmds.c > index aa9ee8a391..bfde769ef0 100644 > --- a/monitor/qmp-cmds.c > +++ b/monitor/qmp-cmds.c > @@ -166,12 +166,12 @@ char *qmp_human_monitor_command(const char *command= _line, bool has_cpu_index, > int64_t cpu_index, Error **errp) > { > char *output =3D NULL; > - MonitorHMP hmp =3D {}; > + MonitorHMP *hmp =3D MONITOR_HMP(object_new(TYPE_MONITOR_HMP)); >=20=20 > - monitor_data_init(&hmp.parent_obj, false, true, false); > + monitor_data_init(&hmp->parent_obj, false, true, false); >=20=20 > if (has_cpu_index) { > - int ret =3D monitor_set_cpu(&hmp.parent_obj, cpu_index); > + int ret =3D monitor_set_cpu(&hmp->parent_obj, cpu_index); > if (ret < 0) { > error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "cpu-index", > "a CPU number"); > @@ -179,14 +179,15 @@ char *qmp_human_monitor_command(const char *command= _line, bool has_cpu_index, > } > } >=20=20 > - handle_hmp_command(&hmp, command_line); > + handle_hmp_command(hmp, command_line); >=20=20 > - WITH_QEMU_LOCK_GUARD(&hmp.parent_obj.mon_lock) { > - output =3D g_strdup(hmp.parent_obj.outbuf->str); > + WITH_QEMU_LOCK_GUARD(&hmp->parent_obj.mon_lock) { > + output =3D g_strdup(hmp->parent_obj.outbuf->str); > } >=20=20 > out: > - monitor_data_destroy(&hmp.parent_obj); > + monitor_data_destroy(&hmp->parent_obj); > + object_unref(hmp); > return output; > } >=20=20 > diff --git a/monitor/qmp.c b/monitor/qmp.c > index cb28a95efd..1ef09352fc 100644 > --- a/monitor/qmp.c > +++ b/monitor/qmp.c > @@ -71,6 +71,20 @@ typedef struct QMPRequest QMPRequest; >=20=20 > QmpCommandList qmp_commands, qmp_cap_negotiation_commands; >=20=20 > +OBJECT_DEFINE_TYPE(MonitorQMP, monitor_qmp, MONITOR_QMP, MONITOR); > + > +static void monitor_qmp_finalize(Object *obj) > +{ > +} > + > +static void monitor_qmp_class_init(ObjectClass *cls, const void *data) > +{ > +} > + > +static void monitor_qmp_init(Object *obj) > +{ > +} > + > static bool qmp_oob_enabled(MonitorQMP *mon) > { > return mon->capab[QMP_CAPABILITY_OOB]; > @@ -513,12 +527,23 @@ static void monitor_qmp_setup_handlers_bh(void *opa= que) > monitor_list_append(&mon->parent_obj); > } >=20=20 > -void monitor_new_qmp(Chardev *chr, bool pretty, Error **errp) > +void monitor_new_qmp(const char *id, Chardev *chr, > + bool pretty, Error **errp) > { > - MonitorQMP *mon =3D g_new0(MonitorQMP, 1); > + MonitorQMP *mon; > + g_autofree char *autoid =3D id ? NULL : monitor_compat_id(); > + Object *obj =3D object_new_with_props(TYPE_MONITOR_QMP, > + object_get_objects_root(), > + id ? id : autoid, > + errp, > + NULL); > + if (!obj) { > + return; > + } > + mon =3D MONITOR_QMP(obj); >=20=20 > if (!qemu_chr_fe_init(&mon->parent_obj.chr, chr, errp)) { > - g_free(mon); > + object_unparent(OBJECT(mon)); > return; > } > qemu_chr_fe_set_echo(&mon->parent_obj.chr, true); > diff --git a/stubs/monitor-internal.c b/stubs/monitor-internal.c > index 23d58da184..20367b7e9a 100644 > --- a/stubs/monitor-internal.c > +++ b/stubs/monitor-internal.c > @@ -8,6 +8,7 @@ int monitor_get_fd(Monitor *mon, const char *name, Error = **errp) > return -1; > } >=20=20 > -void monitor_new_hmp(Chardev *chr, bool use_readline, Error **errp) > +void monitor_new_hmp(const char *id, Chardev *chr, > + bool use_readline, Error **errp) > { > } > diff --git a/system/vl.c b/system/vl.c > index 6643242729..4737c03872 100644 > --- a/system/vl.c > +++ b/system/vl.c > @@ -1252,7 +1252,6 @@ static int mon_init_func(void *opaque, QemuOpts *op= ts, Error **errp) >=20=20 > static void monitor_parse(const char *str, const char *mode, bool pretty) > { > - static int monitor_device_index =3D 0; > QemuOpts *opts; > const char *p; > char label[32]; > @@ -1260,8 +1259,9 @@ static void monitor_parse(const char *str, const ch= ar *mode, bool pretty) > if (strstart(str, "chardev:", &p)) { > snprintf(label, sizeof(label), "%s", p); > } else { > - snprintf(label, sizeof(label), "compat_monitor%d", > - monitor_device_index); > + g_autofree char *id =3D monitor_compat_id(); > + assert(strlen(id) < sizeof(label)); > + memcpy(label, id, strlen(id) + 1); > opts =3D qemu_chr_parse_compat(label, str, true); > if (!opts) { > error_report("parse error: %s", str); > @@ -1277,7 +1277,6 @@ static void monitor_parse(const char *str, const ch= ar *mode, bool pretty) > } else { > assert(pretty =3D=3D false); > } > - monitor_device_index++; Before the patch, we increment the NNN in "compat_monitorNNN" exactly here. Afterwards, we increment it in monitor_compat_id(), which gets called from here and several additional places. If any of the additional places execute before an execution of the original place, NNN change. Feels tolerable, but needs a mention in the commit message. > } >=20=20 > struct device_config {