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Monitor patches for 2026-07-07

GIT PULL Applied Markus Armbruster 4 participants 42 messages Jul 7 – Aug 24

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#0 lore raw

The following changes since commit 94826ec1370328375c3b6d1e80fdc94c8f46c348:

Merge tag 'accel-20260706' of https://github.com/philmd/qemu into staging (2026-07-06 18:38:14 +0200)

are available in the Git repository at:

https://repo.or.cz/qemu/armbru.git tags/pull-monitor-2026-07-07

for you to fetch changes up to 58b70f21ba6364be4f79d9f9c56b334341051bfd:

docs: mark '-mon' as deprecated in favour of -object (2026-07-07 11:16:27 +0200)

----------------------------------------------------------------
Monitor patches for 2026-07-07

----------------------------------------------------------------
Christian Brauner (6):
monitor: convert from oneshot BH to persistent BH
monitor: reject attempts to delete the current monitor
monitor: protect qemu_chr_fe_accept_input with monitor lock
monitor: implement support for deleting QMP objects tests/qtest: add tests for dynamic monitor add/remove tests/functional: add e2e test for dynamic QMP monitor hotplug

Daniel P. Berrangé (29):
qom: replace 'can_be_deleted' with 'prepare_delete'
monitor: replace 'common' with 'parent_obj' in MonitorHMP
monitor: replace 'common' with 'parent_obj' in MonitorQMP
monitor: rename monitor_init* to monitor_new*
monitor: minimal conversion of monitors to QOM
monitor: pass chardev ID into monitor constructor instead of object
monitor: add 'chardev' property to Monitor base class
monitor: add 'readline' property to HMP Monitor class
monitor: add 'pretty' property to QMP Monitor class
monitor: remove 'skip_flush' field
monitor: move monitor_data_(init|destroy) into QOM init/finalize
monitor: use class methods for monitor_vprintf
monitor: use class methods for monitor_qapi_event_emit
monitor: use class methods for monitor_accept_input
monitor: use class method for I/O thread request
monitor: use dynamic cast in monitor_qmp_requests_pop_any_with_lock
util: use dynamic cast in error vreport
monitor: drop unused monitor_cur_is_qmp
monitor: use dynamic cast in QMP commands
monitor: use dynamic cast in monitor_is_hmp_non_interactive
monitor: drop unused monitor_is_qmp method
monitor: eliminate monitor_is_hmp_non_interactive method
monitor: implement "user creatable" interface for adding monitors tests/functional: add a stress test for monitor hot unplug
qom: add trace events for user creatable create/delete APIs
monitor: add support for auto-deleting monitors upon close
tests: switch from -mon to -object monitor-qmp
qemu-options: document new monitor-hmp and monitor-qmp objects
docs: mark '-mon' as deprecated in favour of -object

 MAINTAINERS                                      |   1 +
 docs/about/deprecated.rst                        |  10 +
 docs/devel/writing-monitor-commands.rst          |   4 +-
 docs/system/arm/xenpvh.rst                       |   4 +-
 docs/system/i386/xen.rst                         |   3 +-
 docs/system/i386/xenpvh.rst                      |   4 +-
 qapi/qom.json                                    |  63 +++++
 include/monitor/monitor.h                        |  26 +-
 include/qom/object_interfaces.h                  |  26 +-
 include/system/event-loop-base.h                 |   2 +-
 monitor/monitor-internal.h                       |  73 +++--
 backends/cryptodev.c                             |  12 +-
 backends/hostmem.c                               |   7 +-
 backends/iommufd.c                               |  11 +-
 block/throttle-groups.c                          |  12 +-
 chardev/char.c                                   |   3 +-
 event-loop-base.c                                |   8 +-
 gdbstub/system.c                                 |   2 +-
 migration/migration-hmp-cmds.c                   |   5 +-
 monitor/hmp-cmds.c                               |   7 +-
 monitor/hmp.c                                    | 181 ++++++++++---
 monitor/monitor.c                                | 273 ++++++++++---------
 monitor/qmp-cmds-control.c                       |  12 +-
 monitor/qmp-cmds.c                               |  14 +-
 monitor/qmp.c                                    | 323 ++++++++++++++++++++---
 net/can/can_core.c                               |   6 +-
 qom/object_interfaces.c                          |  20 +-
 storage-daemon/qemu-storage-daemon.c             |   2 +-
 stubs/monitor-core.c                             |   5 -
 stubs/monitor-internal.c                         |   4 +-
 system/vl.c                                      |  19 +-
 tests/qtest/libqtest.c                           |   2 +-
 tests/qtest/qmp-test.c                           | 174 ++++++++++++
 tests/unit/test-util-sockets.c                   |   1 -
 tools/qemu-vnc/stubs.c                           |   5 -
 ui/ui-hmp-cmds.c                                 |   2 +-
 util/error-report.c                              |  13 +-
 util/main-loop.c                                 |   6 +-
 python/qemu/machine/machine.py                   |   4 +-
 qemu-options.hx                                  |  64 ++++-
 qom/trace-events                                 |   5 +
 tests/functional/generic/meson.build             |   1 +
 tests/functional/generic/test_monitor_hotplug.py | 305 +++++++++++++++++++++
 tests/qemu-iotests/245                           |   4 +-
 44 files changed, 1395 insertions(+), 333 deletions(-)
 create mode 100755 tests/functional/generic/test_monitor_hotplug.py
Signature · 1 line
2.54.0
#1 lore raw

[PULL 26/35] monitor: protect qemu_chr_fe_accept_input with monitor lock

From: Christian Brauner <[email protected]>

The monitor_accept_input API is called from a bottom half, and will invoke qemu_chr_fe_accept_input().

When a following patch introduces the ability to delete monitors, it will be neccesary to delete the bottom half. Protecting the call to qemu_chr_fe_accept_input with the monitor lock will allow for synchronization with the deletion process.

[DB: extracted from a larger commit and refactored to apply
to the new monitor class structure]

Message-ID: <[email protected]>

---
 monitor/hmp.c     | 2 ++
 monitor/monitor.c | 6 +-----
 monitor/qmp.c     | 9 +++++++++
 3 files changed, 12 insertions(+), 5 deletions(-)
monitor/hmp.c +2 -0
index 75b93f29a3..71a1888249 100644
@@ -116,9 +116,11 @@ static void monitor_hmp_accept_input(Monitor *mon)
         MonitorHMP *hmp = MONITOR_HMP(mon);
         assert(hmp->rs);
         readline_restart(hmp->rs);
+        qemu_chr_fe_accept_input(&mon->chr);
         qemu_mutex_unlock(&mon->mon_lock);
         readline_show_prompt(hmp->rs);
     } else {
+        qemu_chr_fe_accept_input(&mon->chr);
         qemu_mutex_unlock(&mon->mon_lock);
     }
 }
monitor/monitor.c +1 -5
index de1f761041..4a45c15a36 100644
@@ -562,11 +562,7 @@ static void monitor_accept_input(void *opaque)
     Monitor *mon = opaque;
     MonitorClass *cls = MONITOR_GET_CLASS(mon);
 
-    if (cls->accept_input) {
-        cls->accept_input(mon);
-    }
-
-    qemu_chr_fe_accept_input(&mon->chr);
+    cls->accept_input(mon);
 }
 
 void monitor_resume(Monitor *mon)
monitor/qmp.c +9 -0
index 1c67f40e4a..dc15809145 100644
@@ -107,6 +107,7 @@ static void monitor_qmp_emit_event(Monitor *mon, QAPIEvent event, QDict *qdict);
 static bool monitor_qmp_requires_iothread(const Monitor *mon);
 static void monitor_qmp_complete(UserCreatable *uc, Error **errp);
 static bool monitor_qmp_prepare_delete(UserCreatable *uc, Error **errp);
+static void monitor_qmp_accept_input(Monitor *mon);
 
 static void monitor_qmp_class_init(ObjectClass *cls, const void *data)
 {
@@ -119,6 +120,7 @@ static void monitor_qmp_class_init(ObjectClass *cls, const void *data)
 
     moncls->emit_event = monitor_qmp_emit_event;
     moncls->requires_iothread = monitor_qmp_requires_iothread;
+    moncls->accept_input = monitor_qmp_accept_input;
 
     ucc->complete = monitor_qmp_complete;
     ucc->prepare_delete = monitor_qmp_prepare_delete;
@@ -665,3 +667,10 @@ static bool monitor_qmp_prepare_delete(UserCreatable *uc, Error **errp)
     error_setg(errp, "Deleting QMP monitors is not supported");
     return false;
 }
+
+static void monitor_qmp_accept_input(Monitor *mon)
+{
+    WITH_QEMU_LOCK_GUARD(&mon->mon_lock) {
+        qemu_chr_fe_accept_input(&mon->chr);
+    }
+}
Signature · 1 line
2.54.0
#2 lore raw

[PULL 30/35] tests/functional: add a stress test for monitor hot unplug

In reply to Markus Armbruster

From: Daniel P. Berrangé <[email protected]>

When unplugging a monitor there is a careful synchronization dance between the monitor handling the "object-del" command and the command processing for the monitor being deleted.

The stress test runs a busy loop of 'query-qmp-schema' on a second monitor, while the primary monitor requests its deletion.

Message-ID: <[email protected]>

---
 .../generic/test_monitor_hotplug.py           | 62 +++++++++++++++++++
 1 file changed, 62 insertions(+)
tests/functional/generic/test_monitor_hotplug.py +62 -0
index 5d8a159eb0..55af8a238f 100755
@@ -6,11 +6,16 @@
 #
 # Copyright (c) 2026 Christian Brauner
 
+import asyncio
 import os
+import random
+import threading
+import time
 
 from qemu_test import QemuSystemTest
 
 from qemu.qmp.legacy import QEMUMonitorProtocol
+from qemu.qmp import QMPClient
 
 
 class MonitorHotplug(QemuSystemTest):
@@ -163,6 +168,63 @@ def test_events_after_negotiation(self):
         qmp.close()
         self._remove_monitor()
 
+    def stress_mon(self, sock):
+        async def main():
+            qmp = QMPClient('testvm')
+            await qmp.connect(sock)
+            # Run query-version in a tight loop so that the
+            # monitor thread/dispatcher is very busy at the
+            # time we try to delete the monitor
+            while True:
+                try:
+                    # A command which returns a lot of data to make
+                    # it more likely we're in the I/O reply path
+                    # when deleting the monitor
+                    res = await qmp.execute('query-qmp-schema')
+                    # Some commands which generate async events
+                    # as those can trigger different code paths
+                    res = await qmp.execute('stop')
+                    res = await qmp.execute('cont')
+                except:
+                    # we'll get here if the monitor is terminated
+                    # by QEMU in which case we must disconnect
+                    # out side, but....
+                    try:
+                        await qmp.disconnect()
+                    except (ConnectionResetError, EOFError, BrokenPipeError):
+                        # ... disconnect() will probably see
+                        # errors too, but we must try to call it
+                        # regardless to cleanup asyncio state
+                        # and prevent python warnings at GC time
+                        pass
+                    return
+        asyncio.run(main())
+
+    def test_hotplug_stress(self):
+        """
+        Repeatedly hotplug and unplug a monitor, while another thread
+        concurrently issues commands on that monitor. This stresses
+        the synchronization with the monitor thread during cleanup
+        """
+        self.set_machine('none')
+        self.vm.add_args('-nodefaults')
+        self.vm.launch()
+
+        # Each loop sleeps at most 0.5 seconds, so this should
+        # give an upper bound of approx 5 seconds execution
+        # time which is reasonable to run by default
+        repeat = 10
+        for i in range(repeat):
+            # First cycle
+            sock = self._add_monitor()
+            print ("# stress cycle %02d/%02d" % (i, repeat))
+            stress = threading.Thread(target=self.stress_mon, args=[sock])
+            stress.start()
+            # Sleep upto 1/2 second to vary the races
+            time.sleep(random.random() / 2)
+            self._remove_monitor()
+            stress.join()
+
 
 if __name__ == '__main__':
     QemuSystemTest.main()
Signature · 1 line
2.54.0
#3 lore raw

[PULL 08/35] monitor: add 'readline' property to HMP Monitor class

In reply to Markus Armbruster

From: Daniel P. Berrangé <[email protected]>

This determines whether a human monitor runs with readline for interactive use, or without readline for non-interactive use by the GDB stub.

Message-ID: <[email protected]>

---
 monitor/hmp.c | 27 ++++++++++++++++++++++++++-
 1 file changed, 26 insertions(+), 1 deletion(-)
monitor/hmp.c +26 -1
index 34a39b071c..54fd25f220 100644
@@ -50,12 +50,37 @@ static void monitor_hmp_finalize(Object *obj)
 {
 }
 
+static bool monitor_hmp_get_readline(Object *obj, Error **errp)
+{
+    MonitorHMP *mon = MONITOR_HMP(obj);
+
+    return mon->use_readline;
+}
+
+static void monitor_hmp_set_readline(Object *obj, bool val, Error **errp)
+{
+    MonitorHMP *mon = MONITOR_HMP(obj);
+
+    mon->use_readline = val;
+}
+
 static void monitor_hmp_class_init(ObjectClass *cls, const void *data)
 {
+    object_class_property_add_bool(cls, "readline",
+                                   monitor_hmp_get_readline,
+                                   monitor_hmp_set_readline);
 }
 
 static void monitor_hmp_init(Object *obj)
 {
+    MonitorHMP *hmp = MONITOR_HMP(obj);
+
+    /*
+     * Default to common case for external HMP use,
+     * as opposed to non-interactive internal use
+     * from gdbstub
+     */
+    hmp->use_readline = true;
 }
 
 static void monitor_command_cb(void *opaque, const char *cmdline,
@@ -1550,6 +1575,7 @@ void monitor_new_hmp(const char *id, const char *chardev_id,
                                         id ? id : autoid,
                                         errp,
                                         "chardev", chardev_id,
+                                        "readline", use_readline ? "yes" : "no",
                                         NULL);
 
     if (!obj) {
@@ -1566,7 +1592,6 @@ void monitor_new_hmp(const char *id, const char *chardev_id,
 
     monitor_data_init(&mon->parent_obj, false, false, false);
 
-    mon->use_readline = use_readline;
     if (mon->use_readline) {
         mon->rs = readline_init(monitor_readline_printf,
                                 monitor_readline_flush,
Signature · 1 line
2.54.0
#4 lore raw

[PULL 18/35] monitor: drop unused monitor_cur_is_qmp

In reply to Markus Armbruster

From: Daniel P. Berrangé <[email protected]>

The previous patch dropped the only remaining use of monitor_cur_is_qmp.

Message-ID: <[email protected]>

---
 include/monitor/monitor.h      |  1 -
 monitor/monitor.c              | 10 ----------
 stubs/monitor-core.c           |  5 -----
 tests/unit/test-util-sockets.c |  1 -
 tools/qemu-vnc/stubs.c         |  5 -----
 5 files changed, 22 deletions(-)
include/monitor/monitor.h +0 -1
index 821465f17e..e802e8dfb2 100644
@@ -25,7 +25,6 @@ extern QemuOptsList qemu_mon_opts;
 
 Monitor *monitor_cur(void);
 Monitor *monitor_set_cur(Coroutine *co, Monitor *mon);
-bool monitor_cur_is_qmp(void);
 
 void monitor_init_globals(void);
 void monitor_init_globals_core(void);
monitor/monitor.c +0 -10
index 1b2bdcf68f..a818659392 100644
@@ -152,16 +152,6 @@ Monitor *monitor_set_cur(Coroutine *co, Monitor *mon)
     return old_monitor;
 }
 
-/**
- * Is the current monitor, if any, a QMP monitor?
- */
-bool monitor_cur_is_qmp(void)
-{
-    Monitor *cur_mon = monitor_cur();
-
-    return cur_mon && monitor_is_qmp(cur_mon);
-}
-
 bool monitor_requires_iothread(const Monitor *mon)
 {
     MonitorClass *cls = MONITOR_GET_CLASS(mon);
stubs/monitor-core.c +0 -5
index 078a5012e9..a7c32297c9 100644
@@ -7,11 +7,6 @@ Monitor *monitor_cur(void)
     return NULL;
 }
 
-bool monitor_cur_is_qmp(void)
-{
-    return false;
-}
-
 Monitor *monitor_set_cur(Coroutine *co, Monitor *mon)
 {
     return NULL;
tests/unit/test-util-sockets.c +0 -1
index b9f2453e29..ee66d727c3 100644
@@ -74,7 +74,6 @@ int monitor_get_fd(Monitor *mon, const char *fdname, Error **errp)
 Monitor *monitor_cur(void) { return cur_mon; }
 Monitor *monitor_set_cur(Coroutine *co, Monitor *mon) { abort(); }
 int monitor_vprintf(Monitor *mon, const char *fmt, va_list ap) { abort(); }
-bool monitor_cur_is_qmp(void) { abort(); };
 
 #ifndef _WIN32
 static void test_socket_fd_pass_name_good(void)
tools/qemu-vnc/stubs.c +0 -5
index a865ce85f0..1c82d8cff4 100644
@@ -36,11 +36,6 @@ Monitor *monitor_cur(void)
     return NULL;
 }
 
-bool monitor_cur_is_qmp(void)
-{
-    return false;
-}
-
 Monitor *monitor_set_cur(Coroutine *co, Monitor *mon)
 {
     return NULL;
Signature · 1 line
2.54.0
#5 lore raw

[PULL 13/35] monitor: use class methods for monitor_qapi_event_emit

In reply to Markus Armbruster

From: Daniel P. Berrangé <[email protected]>

This removes the need for using monitor_is_qmp() to check the subclass type, which is an anti-pattern.

Message-ID: <[email protected]>

---
 include/monitor/monitor.h  |  1 +
 monitor/monitor-internal.h |  5 +++++
 monitor/monitor.c          | 15 +++------------
 monitor/qmp.c              | 20 ++++++++++++++++++++
 4 files changed, 29 insertions(+), 12 deletions(-)
include/monitor/monitor.h +1 -0
index bfbeedec9b..821465f17e 100644
@@ -3,6 +3,7 @@
 
 #include "block/block.h"
 #include "qapi/qapi-types-misc.h"
+#include "qapi/qapi-emit-events.h"
 #include "qemu/readline.h"
 #include "exec/hwaddr.h"
 #include "qom/object.h"
monitor/monitor-internal.h +5 -0
index 23cef68153..763b5c9625 100644
@@ -111,6 +111,11 @@ struct MonitorClass {
      */
     int (*vprintf)(Monitor *mon, const char *fmt, va_list ap)
         G_GNUC_PRINTF(2, 0);
+    /*
+     * If non-NULL, the monitor is able to send event
+     * notifications back to the client
+     */
+    void (*emit_event)(Monitor *mon, QAPIEvent event, QDict *qdict);
 };
 
 struct Monitor {
monitor/monitor.c +3 -12
index 0cb0930bf4..90cfb59c66 100644
@@ -348,22 +348,13 @@ static inline QEMUClockType monitor_get_event_clock(void)
 static void monitor_qapi_event_emit(QAPIEvent event, QDict *qdict)
 {
     Monitor *mon;
-    MonitorQMP *qmp_mon;
 
     trace_monitor_protocol_event_emit(event, qdict);
     QTAILQ_FOREACH(mon, &mon_list, entry) {
-        if (!monitor_is_qmp(mon)) {
-            continue;
+        MonitorClass *cls = MONITOR_GET_CLASS(mon);
+        if (cls->emit_event) {
+            cls->emit_event(mon, event, qdict);
         }
-
-        qmp_mon = container_of(mon, MonitorQMP, parent_obj);
-        {
-            QEMU_LOCK_GUARD(&mon->mon_lock);
-            if (qmp_mon->commands == &qmp_cap_negotiation_commands) {
-                continue;
-            }
-        }
-        qmp_send_response(qmp_mon, qdict);
     }
 }
 
monitor/qmp.c +20 -0
index 3574b9a339..d732fff9a3 100644
@@ -99,11 +99,17 @@ static void monitor_qmp_set_pretty(Object *obj, bool val, Error **errp)
     mon->pretty = val;
 }
 
+static void monitor_qmp_emit_event(Monitor *mon, QAPIEvent event, QDict *qdict);
+
 static void monitor_qmp_class_init(ObjectClass *cls, const void *data)
 {
+    MonitorClass *moncls = MONITOR_CLASS(cls);
+
     object_class_property_add_bool(cls, "pretty",
                                    monitor_qmp_get_pretty,
                                    monitor_qmp_set_pretty);
+
+    moncls->emit_event = monitor_qmp_emit_event;
 }
 
 static void handle_qmp_command(void *opaque, QObject *req, Error *err);
@@ -117,6 +123,20 @@ static void monitor_qmp_init(Object *obj)
     json_message_parser_init(&mon->parser, handle_qmp_command, mon, NULL);
 }
 
+static void monitor_qmp_emit_event(Monitor *mon, QAPIEvent event, QDict *qdict)
+{
+    MonitorQMP *qmp = MONITOR_QMP(mon);
+
+    WITH_QEMU_LOCK_GUARD(&mon->mon_lock) {
+        if (qmp->commands == &qmp_cap_negotiation_commands) {
+            return;
+        }
+    }
+
+    qmp_send_response(qmp, qdict);
+}
+
+
 static bool qmp_oob_enabled(MonitorQMP *mon)
 {
     return mon->capab[QMP_CAPABILITY_OOB];
Signature · 1 line
2.54.0
#6 lore raw

[PULL 31/35] qom: add trace events for user creatable create/delete APIs

In reply to Markus Armbruster

From: Daniel P. Berrangé <[email protected]>

Message-ID: <[email protected]>

---
 qom/object_interfaces.c | 11 +++++++++--
 qom/trace-events        |  5 +++++
 2 files changed, 14 insertions(+), 2 deletions(-)
qom/object_interfaces.c +9 -2
index 3216a754ed..d83c12744b 100644
@@ -20,12 +20,14 @@
 #include "qapi/opts-visitor.h"
 #include "qemu/config-file.h"
 #include "qemu/keyval.h"
+#include "trace.h"
 
 bool user_creatable_complete(UserCreatable *uc, Error **errp)
 {
     UserCreatableClass *ucc = USER_CREATABLE_GET_CLASS(uc);
     ERRP_GUARD();
 
+    trace_user_creatable_complete(uc, object_get_typename(OBJECT(uc)));
     if (ucc->complete) {
         ucc->complete(uc, errp);
     }
@@ -35,11 +37,16 @@ bool user_creatable_complete(UserCreatable *uc, Error **errp)
 bool user_creatable_prepare_delete(UserCreatable *uc, Error **errp)
 {
     UserCreatableClass *ucc = USER_CREATABLE_GET_CLASS(uc);
+    bool ret = true;
 
+    trace_user_creatable_prepare_delete(uc, object_get_typename(OBJECT(uc)));
     if (ucc->prepare_delete) {
-        return ucc->prepare_delete(uc, errp);
+        ret = ucc->prepare_delete(uc, errp);
     }
-    return true;
+    trace_user_creatable_prepare_delete_result(
+        uc, object_get_typename(OBJECT(uc)),
+        *errp ? error_get_pretty(*errp) : NULL);
+    return ret;
 }
 
 void user_creatable_add_qapi(ObjectOptions *options, Error **errp)
qom/trace-events +5 -0
index 44c63e72af..bac8472618 100644
@@ -11,3 +11,8 @@ object_property_del_child(void *obj, const char *type, void *child, const char *
 object_property_parse(void *obj, const char *type, const char *name, const char *value) "obj=%p type=%s prop=%s value=%s"
 object_class_dynamic_cast_assert(const char *type, const char *target, const char *file, int line, const char *func) "type=%s->%s (%s:%d:%s)"
 object_class_property_add(const char *type, const char *name, void *value) "type=%s name=%s value=%p"
+
+# object_interfaces.c
+user_creatable_complete(void *obj, const char *type) "obj=%p type=%s"
+user_creatable_prepare_delete(void *obj, const char *type) "obj=%p type=%s"
+user_creatable_prepare_delete_result(void *obj, const char *type, const char *msg) "obj=%p type=%s msg=%s"
Signature · 1 line
2.54.0
#7 lore raw

[PULL 06/35] monitor: pass chardev ID into monitor constructor instead of object

In reply to Markus Armbruster

From: Daniel P. Berrangé <[email protected]>

Current the monitor_new_hmp/monitor_new_qmp constructors accept a Chardev object pointer. To facilitate the next commit which will introduce a QOM property for the character device ID, switch to accepting an chardev ID in the constructor.

Message-ID: <[email protected]>

---
 include/monitor/monitor.h |  4 ++--
 chardev/char.c            |  3 ++-
 gdbstub/system.c          |  2 +-
 monitor/hmp.c             | 22 ++++++++++++++++------
 monitor/monitor.c         | 11 ++---------
 monitor/qmp.c             | 21 +++++++++++++++------
 stubs/monitor-internal.c  |  2 +-
 7 files changed, 39 insertions(+), 26 deletions(-)
include/monitor/monitor.h +2 -2
index 83723f705a..bfbeedec9b 100644
@@ -29,9 +29,9 @@ bool monitor_cur_is_qmp(void);
 void monitor_init_globals(void);
 void monitor_init_globals_core(void);
 char *monitor_compat_id(void);
-void monitor_new_qmp(const char *id, Chardev *chr,
+void monitor_new_qmp(const char *id, const char *chardev_id,
                      bool pretty, Error **errp);
-void monitor_new_hmp(const char *id, Chardev *chr,
+void monitor_new_hmp(const char *id, const char *chardev_id,
                      bool use_readline, Error **errp);
 int monitor_new(MonitorOptions *opts, bool allow_hmp, Error **errp);
 int monitor_new_opts(QemuOpts *opts, Error **errp);
chardev/char.c +2 -1
index c71ffa7963..22e5bae388 100644
@@ -804,8 +804,9 @@ static Chardev *qemu_chr_new_from_name(const char *label, const char *filename,
     }
 
     if (qemu_opt_get_bool(opts, "mux", 0)) {
+        const char *chardev_id = qemu_opts_id(opts);
         assert(permit_mux_mon);
-        monitor_new_hmp(NULL, chr, true, &err);
+        monitor_new_hmp(NULL, chardev_id, true, &err);
         if (err) {
             error_report_err(err);
             object_unparent(OBJECT(chr));
gdbstub/system.c +1 -1
index e51d32fa65..c77d067ab4 100644
@@ -390,7 +390,7 @@ bool gdbserver_start(const char *device, Error **errp)
         /* Initialize a monitor terminal for gdb */
         mon_chr = qemu_chardev_new(NULL, TYPE_CHARDEV_GDB,
                                    NULL, NULL, &error_abort);
-        monitor_new_hmp(NULL, mon_chr, false, &error_abort);
+        monitor_new_hmp(NULL, mon_chr->label, false, &error_abort);
     } else {
         qemu_chr_fe_deinit(&gdbserver_system_state.chr, true);
         mon_chr = gdbserver_system_state.mon_chr;
monitor/hmp.c +16 -6
index da11e56854..1704166326 100644
@@ -39,6 +39,7 @@
 #include "qemu/base-arch-defs.h"
 #include "qemu/target-info.h"
 #include "qemu/units.h"
+#include "qapi/error.h"
 #include "exec/gdbstub.h"
 #include "system/block-backend.h"
 #include "trace.h"
@@ -1538,16 +1539,25 @@ static void monitor_readline_flush(void *opaque)
     monitor_flush(&mon->parent_obj);
 }
 
-void monitor_new_hmp(const char *id, Chardev *chr,
+void monitor_new_hmp(const char *id, const char *chardev_id,
                      bool use_readline, Error **errp)
 {
     MonitorHMP *mon;
     g_autofree char *autoid = id ? NULL : monitor_compat_id();
-    Object *obj = object_new_with_props(TYPE_MONITOR_HMP,
-                                        object_get_objects_root(),
-                                        id ? id : autoid,
-                                        errp,
-                                        NULL);
+    Chardev *chr;
+    Object *obj;
+
+    chr = qemu_chr_find(chardev_id);
+    if (chr == NULL) {
+        error_setg(errp, "chardev \"%s\" not found", chardev_id);
+        return;
+    }
+
+    obj = object_new_with_props(TYPE_MONITOR_HMP,
+                                object_get_objects_root(),
+                                id ? id : autoid,
+                                errp,
+                                NULL);
     if (!obj) {
         return;
     }
monitor/monitor.c +2 -9
index 18a1d8ddde..cb0299a2f7 100644
@@ -741,13 +741,6 @@ char *monitor_compat_id(void)
 int monitor_new(MonitorOptions *opts, bool allow_hmp, Error **errp)
 {
     ERRP_GUARD();
-    Chardev *chr;
-
-    chr = qemu_chr_find(opts->chardev);
-    if (chr == NULL) {
-        error_setg(errp, "chardev \"%s\" not found", opts->chardev);
-        return -1;
-    }
 
     if (!opts->has_mode) {
         opts->mode = allow_hmp ? MONITOR_MODE_READLINE : MONITOR_MODE_CONTROL;
@@ -755,7 +748,7 @@ int monitor_new(MonitorOptions *opts, bool allow_hmp, Error **errp)
 
     switch (opts->mode) {
     case MONITOR_MODE_CONTROL:
-        monitor_new_qmp(opts->id, chr, opts->pretty, errp);
+        monitor_new_qmp(opts->id, opts->chardev, opts->pretty, errp);
         break;
     case MONITOR_MODE_READLINE:
         if (!allow_hmp) {
@@ -766,7 +759,7 @@ int monitor_new(MonitorOptions *opts, bool allow_hmp, Error **errp)
             error_setg(errp, "'pretty' is not compatible with HMP monitors");
             return -1;
         }
-        monitor_new_hmp(opts->id, chr, true, errp);
+        monitor_new_hmp(opts->id, opts->chardev, true, errp);
         break;
     default:
         g_assert_not_reached();
monitor/qmp.c +15 -6
index 1ef09352fc..e2f841212b 100644
@@ -527,16 +527,25 @@ static void monitor_qmp_setup_handlers_bh(void *opaque)
     monitor_list_append(&mon->parent_obj);
 }
 
-void monitor_new_qmp(const char *id, Chardev *chr,
+void monitor_new_qmp(const char *id, const char *chardev_id,
                      bool pretty, Error **errp)
 {
     MonitorQMP *mon;
     g_autofree char *autoid = id ? NULL : monitor_compat_id();
-    Object *obj = object_new_with_props(TYPE_MONITOR_QMP,
-                                        object_get_objects_root(),
-                                        id ? id : autoid,
-                                        errp,
-                                        NULL);
+    Chardev *chr;
+    Object *obj;
+
+    chr = qemu_chr_find(chardev_id);
+    if (chr == NULL) {
+        error_setg(errp, "chardev \"%s\" not found", chardev_id);
+        return;
+    }
+
+    obj = object_new_with_props(TYPE_MONITOR_QMP,
+                                object_get_objects_root(),
+                                id ? id : autoid,
+                                errp,
+                                NULL);
     if (!obj) {
         return;
     }
stubs/monitor-internal.c +1 -1
index 20367b7e9a..f94b5e5c21 100644
@@ -8,7 +8,7 @@ int monitor_get_fd(Monitor *mon, const char *name, Error **errp)
     return -1;
 }
 
-void monitor_new_hmp(const char *id, Chardev *chr,
+void monitor_new_hmp(const char *id, const char *chardev_id,
                      bool use_readline, Error **errp)
 {
 }
Signature · 1 line
2.54.0
#8 lore raw

[PULL 11/35] monitor: move monitor_data_(init|destroy) into QOM init/finalize

In reply to Markus Armbruster

From: Daniel P. Berrangé <[email protected]>

Start to take advantage of QOM, by using object init and finalize methods to replace monitor_data_init and monitor_data_destroy.

A standalone helper is provided to enable the I/O thread for QMP where appropriate for the chardev backend.

Message-ID: <[email protected]>

---
 monitor/monitor-internal.h |  3 +--
 monitor/hmp.c              |  6 +++--
 monitor/monitor.c          | 46 +++++++++++++-------------------------
 monitor/qmp-cmds.c         |  3 ---
 monitor/qmp.c              | 34 +++++++++++++++-------------
 5 files changed, 40 insertions(+), 52 deletions(-)
monitor/monitor-internal.h +1 -2
index d34f9be139..6a4c3b0f37 100644
@@ -193,8 +193,7 @@ extern QemuMutex monitor_lock;
 extern MonitorList mon_list;
 
 void monitor_complete(Monitor *mon, Error **errp);
-void monitor_data_init(Monitor *mon, bool is_qmp, bool use_io_thread);
-void monitor_data_destroy(Monitor *mon);
+void monitor_iothread_init(Monitor *mon);
 int monitor_can_read(void *opaque);
 void monitor_list_append(Monitor *mon);
 void monitor_fdsets_cleanup(void);
monitor/hmp.c +4 -2
index 5644c9c4f5..c03b91782c 100644
@@ -48,6 +48,10 @@ OBJECT_DEFINE_TYPE(MonitorHMP, monitor_hmp, MONITOR_HMP, MONITOR);
 
 static void monitor_hmp_finalize(Object *obj)
 {
+    MonitorHMP *mon = MONITOR_HMP(obj);
+    if (mon->rs) {
+        readline_free(mon->rs);
+    }
 }
 
 static bool monitor_hmp_get_readline(Object *obj, Error **errp)
@@ -1590,8 +1594,6 @@ void monitor_new_hmp(const char *id, const char *chardev_id,
         return;
     }
 
-    monitor_data_init(&mon->parent_obj, false, false);
-
     if (mon->use_readline) {
         mon->rs = readline_init(monitor_readline_printf,
                                 monitor_readline_flush,
monitor/monitor.c +16 -30

88 lines not on this page · raw message

monitor/qmp-cmds.c +0 -3
index 0d9adad288..6cb0b587fb 100644
@@ -168,8 +168,6 @@ char *qmp_human_monitor_command(const char *command_line, bool has_cpu_index,
     char *output = NULL;
     MonitorHMP *hmp = MONITOR_HMP(object_new(TYPE_MONITOR_HMP));
 
-    monitor_data_init(&hmp->parent_obj, false, false);
-
     if (has_cpu_index) {
         int ret = monitor_set_cpu(&hmp->parent_obj, cpu_index);
         if (ret < 0) {
@@ -186,7 +184,6 @@ char *qmp_human_monitor_command(const char *command_line, bool has_cpu_index,
     }
 
 out:
-    monitor_data_destroy(&hmp->parent_obj);
     object_unref(hmp);
     return output;
 }
monitor/qmp.c +19 -15
index b300886f33..3574b9a339 100644
@@ -73,8 +73,16 @@ QmpCommandList qmp_commands, qmp_cap_negotiation_commands;
 
 OBJECT_DEFINE_TYPE(MonitorQMP, monitor_qmp, MONITOR_QMP, MONITOR);
 
+static void monitor_qmp_cleanup_req_queue_locked(MonitorQMP *mon);
+
 static void monitor_qmp_finalize(Object *obj)
 {
+    MonitorQMP *mon = MONITOR_QMP(obj);
+
+    json_message_parser_destroy(&mon->parser);
+    qemu_mutex_destroy(&mon->qmp_queue_lock);
+    monitor_qmp_cleanup_req_queue_locked(mon);
+    g_queue_free(mon->qmp_requests);
 }
 
 static bool monitor_qmp_get_pretty(Object *obj, Error **errp)
@@ -98,8 +106,15 @@ static void monitor_qmp_class_init(ObjectClass *cls, const void *data)
                                    monitor_qmp_set_pretty);
 }
 
+static void handle_qmp_command(void *opaque, QObject *req, Error *err);
 static void monitor_qmp_init(Object *obj)
 {
+    MonitorQMP *mon = MONITOR_QMP(obj);
+
+    qemu_mutex_init(&mon->qmp_queue_lock);
+    mon->qmp_requests = g_queue_new();
+
+    json_message_parser_init(&mon->parser, handle_qmp_command, mon, NULL);
 }
 
 static bool qmp_oob_enabled(MonitorQMP *mon)
@@ -522,14 +537,6 @@ static void monitor_qmp_event(void *opaque, QEMUChrEvent event)
     }
 }
 
-void monitor_data_destroy_qmp(MonitorQMP *mon)
-{
-    json_message_parser_destroy(&mon->parser);
-    qemu_mutex_destroy(&mon->qmp_queue_lock);
-    monitor_qmp_cleanup_req_queue_locked(mon);
-    g_queue_free(mon->qmp_requests);
-}
-
 static void monitor_qmp_setup_handlers_bh(void *opaque)
 {
     MonitorQMP *mon = opaque;
@@ -572,14 +579,11 @@ void monitor_new_qmp(const char *id, const char *chardev_id,
     qemu_chr_fe_set_echo(&mon->parent_obj.chr, true);
 
     /* Note: we run QMP monitor in I/O thread when @chr supports that */
-    monitor_data_init(&mon->parent_obj, true,
-                      qemu_chr_has_feature(mon->parent_obj.chr.chr,
-                                           QEMU_CHAR_FEATURE_GCONTEXT));
+    if (qemu_chr_has_feature(mon->parent_obj.chr.chr,
+                             QEMU_CHAR_FEATURE_GCONTEXT)) {
+        monitor_iothread_init(&mon->parent_obj);
+    }
 
-    qemu_mutex_init(&mon->qmp_queue_lock);
-    mon->qmp_requests = g_queue_new();
-
-    json_message_parser_init(&mon->parser, handle_qmp_command, mon, NULL);
     if (mon->parent_obj.use_io_thread) {
         /*
          * Make sure the old iowatch is gone.  It's possible when
Signature · 1 line
2.54.0
#9 lore raw

[PULL 15/35] monitor: use class method for I/O thread request

In reply to Markus Armbruster

From: Daniel P. Berrangé <[email protected]>

Introducing a virtual "requires_iothread" method allows the code to automatically initialize the I/O thread during object completion.

Message-ID: <[email protected]>

---
 monitor/monitor-internal.h | 14 +++++++++-----
 monitor/monitor.c          | 22 ++++++++++++----------
 monitor/qmp.c              | 20 +++++++++++---------
 3 files changed, 32 insertions(+), 24 deletions(-)
monitor/monitor-internal.h +9 -5
index 592f146331..efd21b8912 100644
@@ -121,6 +121,12 @@ struct MonitorClass {
      * the monitor to accept further client input
      */
     void (*accept_input)(Monitor *mon);
+
+    /*
+     * If non-NULL and returns true, then an I/O thread
+     * is required for processing the monitor
+     */
+    bool (*requires_iothread)(const Monitor *mon);
 };
 
 struct Monitor {
@@ -129,7 +135,6 @@ struct Monitor {
     CharFrontend chr;
     int suspend_cnt;            /* Needs to be accessed atomically */
     bool is_qmp;
-    bool use_io_thread;
 
     char *mon_cpu_path;
     QTAILQ_ENTRY(Monitor) entry;
@@ -159,9 +164,8 @@ struct MonitorHMP {
     bool use_readline;
     /*
      * State used only in the thread "owning" the monitor.
-     * If @use_io_thread, this is @mon_iothread. (This does not actually happen
-     * in the current state of the code.)
-     * Else, it's the main thread.
+     * This is currently always the main thread, since
+     * HMP does not allow use of the I/O thread at this time.
      * These members can be safely accessed without locks.
      */
     ReadLineState *rs;
@@ -210,7 +214,7 @@ extern QemuMutex monitor_lock;
 extern MonitorList mon_list;
 
 void monitor_complete(Monitor *mon, Error **errp);
-void monitor_iothread_init(Monitor *mon);
+bool monitor_requires_iothread(const Monitor *mon);
 int monitor_can_read(void *opaque);
 void monitor_list_append(Monitor *mon);
 void monitor_fdsets_cleanup(void);
monitor/monitor.c +12 -10
index 6e63e7a5c7..1b2bdcf68f 100644
@@ -162,6 +162,12 @@ bool monitor_cur_is_qmp(void)
     return cur_mon && monitor_is_qmp(cur_mon);
 }
 
+bool monitor_requires_iothread(const Monitor *mon)
+{
+    MonitorClass *cls = MONITOR_GET_CLASS(mon);
+    return cls->requires_iothread && cls->requires_iothread(mon);
+}
+
 /**
  * Is @mon is using readline?
  * Note: not all HMP monitors use readline, e.g., gdbserver has a
@@ -563,7 +569,7 @@ int monitor_suspend(Monitor *mon)
 
     qatomic_inc(&mon->suspend_cnt);
 
-    if (mon->use_io_thread) {
+    if (monitor_requires_iothread(mon)) {
         /*
          * Kick I/O thread to make sure this takes effect.  It'll be
          * evaluated again in prepare() of the watch object.
@@ -596,7 +602,7 @@ void monitor_resume(Monitor *mon)
     if (qatomic_dec_fetch(&mon->suspend_cnt) == 0) {
         AioContext *ctx;
 
-        if (mon->use_io_thread) {
+        if (monitor_requires_iothread(mon)) {
             ctx = iothread_get_aio_context(mon_iothread);
         } else {
             ctx = qemu_get_aio_context();
@@ -634,14 +640,6 @@ void monitor_list_append(Monitor *mon)
     }
 }
 
-void monitor_iothread_init(Monitor *mon)
-{
-    if (!mon_iothread) {
-        mon_iothread = iothread_create("mon_iothread", &error_abort);
-    }
-    mon->use_io_thread = true;
-}
-
 void monitor_cleanup(void)
 {
     /*
@@ -743,6 +741,10 @@ void monitor_complete(Monitor *mon, Error **errp)
             return;
         }
     }
+
+    if (monitor_requires_iothread(mon) && !mon_iothread) {
+        mon_iothread = iothread_create("mon_iothread", &error_abort);
+    }
 }
 
 int monitor_new(MonitorOptions *opts, bool allow_hmp, Error **errp)
monitor/qmp.c +11 -9
index d732fff9a3..8bbe25d8de 100644
@@ -100,6 +100,7 @@ static void monitor_qmp_set_pretty(Object *obj, bool val, Error **errp)
 }
 
 static void monitor_qmp_emit_event(Monitor *mon, QAPIEvent event, QDict *qdict);
+static bool monitor_qmp_requires_iothread(const Monitor *mon);
 
 static void monitor_qmp_class_init(ObjectClass *cls, const void *data)
 {
@@ -110,6 +111,7 @@ static void monitor_qmp_class_init(ObjectClass *cls, const void *data)
                                    monitor_qmp_set_pretty);
 
     moncls->emit_event = monitor_qmp_emit_event;
+    moncls->requires_iothread = monitor_qmp_requires_iothread;
 }
 
 static void handle_qmp_command(void *opaque, QObject *req, Error *err);
@@ -136,6 +138,11 @@ static void monitor_qmp_emit_event(Monitor *mon, QAPIEvent event, QDict *qdict)
     qmp_send_response(qmp, qdict);
 }
 
+static bool monitor_qmp_requires_iothread(const Monitor *mon)
+{
+    return qemu_chr_has_feature(mon->chr.chr,
+                                QEMU_CHAR_FEATURE_GCONTEXT);
+}
 
 static bool qmp_oob_enabled(MonitorQMP *mon)
 {
@@ -146,7 +153,8 @@ static void monitor_qmp_caps_reset(MonitorQMP *mon)
 {
     memset(mon->capab_offered, 0, sizeof(mon->capab_offered));
     memset(mon->capab, 0, sizeof(mon->capab));
-    mon->capab_offered[QMP_CAPABILITY_OOB] = mon->parent_obj.use_io_thread;
+    mon->capab_offered[QMP_CAPABILITY_OOB] =
+        monitor_requires_iothread(MONITOR(mon));
 }
 
 static void qmp_request_free(QMPRequest *req)
@@ -562,7 +570,7 @@ static void monitor_qmp_setup_handlers_bh(void *opaque)
     MonitorQMP *mon = opaque;
     GMainContext *context;
 
-    assert(mon->parent_obj.use_io_thread);
+    assert(monitor_requires_iothread(MONITOR(mon)));
     context = iothread_get_g_main_context(mon_iothread);
     assert(context);
     qemu_chr_fe_set_handlers(&mon->parent_obj.chr, monitor_can_read,
@@ -598,13 +606,7 @@ void monitor_new_qmp(const char *id, const char *chardev_id,
 
     qemu_chr_fe_set_echo(&mon->parent_obj.chr, true);
 
-    /* Note: we run QMP monitor in I/O thread when @chr supports that */
-    if (qemu_chr_has_feature(mon->parent_obj.chr.chr,
-                             QEMU_CHAR_FEATURE_GCONTEXT)) {
-        monitor_iothread_init(&mon->parent_obj);
-    }
-
-    if (mon->parent_obj.use_io_thread) {
+    if (monitor_requires_iothread(MONITOR(mon))) {
         /*
          * Make sure the old iowatch is gone.  It's possible when
          * e.g. the chardev is in client mode, with wait=on.
Signature · 1 line
2.54.0
#10 lore raw

[PULL 25/35] monitor: reject attempts to delete the current monitor

In reply to Markus Armbruster

From: Christian Brauner <[email protected]>

If an 'object_del' command for a QMP monitor arrives targetting the current monitor, reject this request. If the current monitor is deleted, it will be impossible to send any reply and the client won't be able to remove the corresponding chardev backend.

Note, it is not possible to rely on checking monitor_cur() because if 'object_del' is called via human-monitor-command, monitor_cur() will reflect the temporary HMP, not the QMP target that needs to be checked.

[DB: extracted monitor tracking from larger commit; added logic
to monitor_qmp_prepare_delete to reject request]

Message-ID: <[email protected]>

---
 monitor/qmp.c | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)
monitor/qmp.c +17 -0
index 67ee491f5a..1c67f40e4a 100644
@@ -72,6 +72,9 @@ typedef struct QMPRequest QMPRequest;
 
 QmpCommandList qmp_commands, qmp_cap_negotiation_commands;
 
+/* Monitor being serviced by the dispatcher.  Protected by BQL. */
+static MonitorQMP *qmp_dispatcher_current_mon;
+
 OBJECT_DEFINE_TYPE(MonitorQMP, monitor_qmp, MONITOR_QMP, MONITOR);
 
 static void monitor_qmp_cleanup_req_queue_locked(MonitorQMP *mon);
@@ -369,6 +372,7 @@ void coroutine_fn monitor_qmp_dispatcher_co(void *data)
          */
 
         mon = req_obj->mon;
+        qmp_dispatcher_current_mon = mon;
 
         /*
          * We need to resume the monitor if handle_qmp_command()
@@ -429,6 +433,7 @@ void coroutine_fn monitor_qmp_dispatcher_co(void *data)
         }
 
         qmp_request_free(req_obj);
+        qmp_dispatcher_current_mon = NULL;
     }
     qatomic_set(&qmp_dispatcher_co, NULL);
 }
@@ -573,6 +578,11 @@ static void monitor_qmp_event(void *opaque, QEMUChrEvent event)
     }
 }
 
+static bool monitor_qmp_dispatcher_is_servicing(MonitorQMP *mon)
+{
+    return qmp_dispatcher_current_mon == mon;
+}
+
 static void monitor_qmp_setup_handlers_bh(void *opaque)
 {
     MonitorQMP *mon = opaque;
@@ -645,6 +655,13 @@ static void monitor_qmp_complete(UserCreatable *uc, Error **errp)
 
 static bool monitor_qmp_prepare_delete(UserCreatable *uc, Error **errp)
 {
+    MonitorQMP *qmp = MONITOR_QMP(uc);
+
+    if (monitor_qmp_dispatcher_is_servicing(qmp)) {
+        error_setg(errp, "Cannot delete the current QMP monitor");
+        return false;
+    }
+
     error_setg(errp, "Deleting QMP monitors is not supported");
     return false;
 }
Signature · 1 line
2.54.0
#11 lore raw

[PULL 07/35] monitor: add 'chardev' property to Monitor base class

In reply to Markus Armbruster

From: Daniel P. Berrangé <[email protected]>

This is associates both QMP and HMP monitors with a character device backend.

Message-ID: <[email protected]>

---
 monitor/monitor-internal.h |  2 ++
 monitor/hmp.c              | 24 ++++++++++--------------
 monitor/monitor.c          | 36 ++++++++++++++++++++++++++++++++++++
 monitor/qmp.c              | 33 +++++++++++++++------------------
 4 files changed, 63 insertions(+), 32 deletions(-)
monitor/monitor-internal.h +2 -0
index 05c1f2f5e0..145d52fd71 100644
@@ -108,6 +108,7 @@ struct MonitorClass {
 
 struct Monitor {
     Object parent;
+    char *chardev_id;
     CharFrontend chr;
     int suspend_cnt;            /* Needs to be accessed atomically */
     bool is_qmp;
@@ -192,6 +193,7 @@ extern QmpCommandList qmp_commands, qmp_cap_negotiation_commands;
 extern QemuMutex monitor_lock;
 extern MonitorList mon_list;
 
+void monitor_complete(Monitor *mon, Error **errp);
 void monitor_data_init(Monitor *mon, bool is_qmp, bool skip_flush,
                        bool use_io_thread);
 void monitor_data_destroy(Monitor *mon);
monitor/hmp.c +10 -14
index 1704166326..34a39b071c 100644
@@ -1542,28 +1542,24 @@ static void monitor_readline_flush(void *opaque)
 void monitor_new_hmp(const char *id, const char *chardev_id,
                      bool use_readline, Error **errp)
 {
+    ERRP_GUARD();
     MonitorHMP *mon;
     g_autofree char *autoid = id ? NULL : monitor_compat_id();
-    Chardev *chr;
-    Object *obj;
+    Object *obj = object_new_with_props(TYPE_MONITOR_HMP,
+                                        object_get_objects_root(),
+                                        id ? id : autoid,
+                                        errp,
+                                        "chardev", chardev_id,
+                                        NULL);
 
-    chr = qemu_chr_find(chardev_id);
-    if (chr == NULL) {
-        error_setg(errp, "chardev \"%s\" not found", chardev_id);
-        return;
-    }
-
-    obj = object_new_with_props(TYPE_MONITOR_HMP,
-                                object_get_objects_root(),
-                                id ? id : autoid,
-                                errp,
-                                NULL);
     if (!obj) {
         return;
     }
+
     mon = MONITOR_HMP(obj);
 
-    if (!qemu_chr_fe_init(&mon->parent_obj.chr, chr, errp)) {
+    monitor_complete(MONITOR(mon), errp);
+    if (*errp) {
         object_unparent(OBJECT(mon));
         return;
     }
monitor/monitor.c +36 -0
index cb0299a2f7..1648946c92 100644
@@ -79,10 +79,31 @@ OBJECT_DEFINE_ABSTRACT_TYPE(Monitor, monitor, MONITOR, OBJECT);
 
 static void monitor_finalize(Object *obj)
 {
+    Monitor *mon = MONITOR(obj);
+
+    g_free(mon->chardev_id);
+}
+
+static char *monitor_get_chardev_id(Object *obj, Error **errp)
+{
+    Monitor *mon = MONITOR(obj);
+
+    return g_strdup(mon->chardev_id);
+}
+
+static void monitor_set_chardev_id(Object *obj, const char *str, Error **errp)
+{
+    Monitor *mon = MONITOR(obj);
+
+    g_free(mon->chardev_id);
+    mon->chardev_id = g_strdup(str);
 }
 
 static void monitor_class_init(ObjectClass *cls, const void *data)
 {
+    object_class_property_add_str(cls, "chardev",
+                                  monitor_get_chardev_id,
+                                  monitor_set_chardev_id);
 }
 
 static void monitor_init(Object *obj)
@@ -738,6 +759,21 @@ char *monitor_compat_id(void)
     return g_strdup_printf("compat_monitor%d", monitor_device_index++);
 }
 
+void monitor_complete(Monitor *mon, Error **errp)
+{
+    if (mon->chardev_id) {
+        Chardev *chr = qemu_chr_find(mon->chardev_id);
+        if (chr == NULL) {
+            error_setg(errp, "chardev \"%s\" not found", mon->chardev_id);
+            return;
+        }
+
+        if (!qemu_chr_fe_init(&mon->chr, chr, errp)) {
+            return;
+        }
+    }
+}
+
 int monitor_new(MonitorOptions *opts, bool allow_hmp, Error **errp)
 {
     ERRP_GUARD();
monitor/qmp.c +15 -18
index e2f841212b..df35b530ed 100644
@@ -530,36 +530,33 @@ static void monitor_qmp_setup_handlers_bh(void *opaque)
 void monitor_new_qmp(const char *id, const char *chardev_id,
                      bool pretty, Error **errp)
 {
+    ERRP_GUARD();
     MonitorQMP *mon;
     g_autofree char *autoid = id ? NULL : monitor_compat_id();
-    Chardev *chr;
-    Object *obj;
+    Object *obj = object_new_with_props(TYPE_MONITOR_QMP,
+                                        object_get_objects_root(),
+                                        id ? id : autoid,
+                                        errp,
+                                        "chardev", chardev_id,
+                                        NULL);
 
-    chr = qemu_chr_find(chardev_id);
-    if (chr == NULL) {
-        error_setg(errp, "chardev \"%s\" not found", chardev_id);
-        return;
-    }
-
-    obj = object_new_with_props(TYPE_MONITOR_QMP,
-                                object_get_objects_root(),
-                                id ? id : autoid,
-                                errp,
-                                NULL);
     if (!obj) {
         return;
     }
-    mon = MONITOR_QMP(obj);
 
-    if (!qemu_chr_fe_init(&mon->parent_obj.chr, chr, errp)) {
+    mon = MONITOR_QMP(obj);
+    monitor_complete(MONITOR(mon), errp);
+    if (*errp) {
         object_unparent(OBJECT(mon));
         return;
     }
+
     qemu_chr_fe_set_echo(&mon->parent_obj.chr, true);
 
     /* Note: we run QMP monitor in I/O thread when @chr supports that */
     monitor_data_init(&mon->parent_obj, true, false,
-                      qemu_chr_has_feature(chr, QEMU_CHAR_FEATURE_GCONTEXT));
+                      qemu_chr_has_feature(mon->parent_obj.chr.chr,
+                                           QEMU_CHAR_FEATURE_GCONTEXT));
 
     mon->pretty = pretty;
 
@@ -572,12 +569,12 @@ void monitor_new_qmp(const char *id, const char *chardev_id,
          * Make sure the old iowatch is gone.  It's possible when
          * e.g. the chardev is in client mode, with wait=on.
          */
-        remove_fd_in_watch(chr);
+        remove_fd_in_watch(mon->parent_obj.chr.chr);
         /*
          * Clean up listener IO sources early to prevent racy fd
          * handling between the main thread and the I/O thread.
          */
-        remove_listener_fd_in_watch(chr);
+        remove_listener_fd_in_watch(mon->parent_obj.chr.chr);
         /*
          * We can't call qemu_chr_fe_set_handlers() directly here
          * since chardev might be running in the monitor I/O
Signature · 1 line
2.54.0
#12 lore raw

[PULL 34/35] qemu-options: document new monitor-hmp and monitor-qmp objects

In reply to Markus Armbruster

From: Daniel P. Berrangé <[email protected]>

Add new docs for the -object monitor-hmp and -object monitor-qmp options, updating -mon to state that it is legacy syntax sugar for the new -object args.

Message-ID: <[email protected]>

---
 qemu-options.hx | 61 ++++++++++++++++++++++++++++++++++++++++++++++---
 1 file changed, 58 insertions(+), 3 deletions(-)
qemu-options.hx +58 -3
index e44b47de68..fe76c18c81 100644
@@ -4955,6 +4955,11 @@ SRST
     port). The default device is ``vc`` in graphical mode and ``stdio``
     in non graphical mode. Use ``-monitor none`` to disable the default
     monitor.
+
+    The use of ``-monitor dev`` is syntactic sugar for creating a character
+    device from ``dev`` and pairing it with ``-object monitor-hmp``.
+    Both the character device and monitor object will be given an ID
+    ``compat_monitorNNN`` where ``NNN`` is a counter starting from 0.
 ERST
 DEF("qmp", HAS_ARG, QEMU_OPTION_qmp, \
     "-qmp dev        like -monitor but opens in 'control' mode\n",
@@ -4966,9 +4971,10 @@ SRST
 
         -qmp tcp:localhost:4444,server=on,wait=off
 
-    Not all options are configurable via this syntax; for maximum
-    flexibility use the ``-mon`` option and an accompanying ``-chardev``.
-
+    The use of ``-qmp dev`` is syntactic sugar for creating a character
+    device from ``dev`` and pairing it with ``-object monitor-qmp``.
+    Both the character device and monitor object will be given an ID
+    ``compat_monitorNNN`` where ``NNN`` is a counter starting from 0.
 ERST
 DEF("qmp-pretty", HAS_ARG, QEMU_OPTION_qmp_pretty, \
     "-qmp-pretty dev like -qmp but uses pretty JSON formatting\n",
@@ -4997,6 +5003,16 @@ SRST
       -mon chardev=mon1,mode=control,pretty=on
 
     enables the QMP monitor on localhost port 4444 with pretty-printing.
+
+    The use of ``-mon mode=readline`` is syntactic sugar
+    for the new ``-object monitor-hmp`` option, each use of which
+    creates an object with the ID ``compat_monitorNNN`` where ``NNN`` is
+    a counter starting from 0.
+
+    The use of ``-mon mode=control`` is syntactic sugar
+    for the new ``-object monitor-qmp`` option, each use of which
+    creates an object with the ID ``compat_monitorNNN`` where ``NNN`` is
+    a counter starting from 0.
 ERST
 
 DEF("debugcon", HAS_ARG, QEMU_OPTION_debugcon, \
@@ -5747,6 +5763,45 @@ SRST
     they are specified. Note that the 'id' property must be set. These
     objects are placed in the '/objects' path.
 
+    ``-object monitor-hmp,id=id,chardev=chardev_id,readline=on|off``
+        Set up a monitor running the Human Monitor Protocol,
+        connected to the chardev ``chardev_id``.
+
+        The ``id`` parameter is a unique ID that can be used
+        to dynamically delete the monitor at runtime. Note
+        that monitors created using the historical syntax
+        will be allocated IDs following the pattern ``compat_monmitorNNN``.
+        Mixing ``-object`` with ``-monitor`` and ``-mon`` syntax is
+        discouraged.
+
+        The ``readline`` parameter, which defaults to ``on``,
+        controls whether the monitor provides line editing.
+
+    ``-object monitor-qmp,id=id,chardev=chardev_id,pretty=on|off,close-action=none|delete``
+        Set up a monitor running the QEMU Monitor Protocol,
+        connected to the chardev ``chardev_id``.
+
+        The ``id`` parameter is a unique ID that can be used
+        to dynamically delete the monitor at runtime. Note
+        that monitors created using the historical syntax
+        will be allocated IDs following the pattern ``compat_monitorNNN``.
+        Mixing ``-object`` with ``-qmp``, ``-qmp-pretty`` and
+        ``-mon`` syntax is discouraged.
+
+        The ``pretty`` parameter, which defaults to ``off``,
+        controls whether the monitor responses are pretty
+        printed as multi-line indented JSON, as opposed to
+        constrained to a single line without extraneous
+        whitespace.
+
+        The ``close-action`` parameter, which defaults to ``none``,
+        controls what happens when the connection to the monitor
+        is terminated by the user. If set to ``delete``, then the
+        ``monitor-qmp`` object and its associated character
+        device are both immediately deleted. This can be useful
+        if an extra monitor was hotplugged for a specific task
+        and should be unplugged when completed.
+
     ``-object memory-backend-file,id=id,size=size,mem-path=dir,share=on|off,discard-data=on|off,merge=on|off,dump=on|off,prealloc=on|off,host-nodes=host-nodes,policy=default|preferred|bind|interleave,align=align,offset=offset,readonly=on|off,rom=on|off|auto``
         Creates a memory file backend object, which can be used to back
         the guest RAM with huge pages.
Signature · 1 line
2.54.0
#13 lore raw

[PULL 24/35] monitor: convert from oneshot BH to persistent BH

In reply to Markus Armbruster

From: Christian Brauner <[email protected]>

Convert monitor_accept_input from a oneshot BH (aio_bh_schedule_oneshot) to a persistent BH (aio_bh_new + qemu_bh_schedule). Oneshot BHs cannot be cancelled, so monitor_resume() racing with destruction would schedule a callback against memory that monitor_qmp_destroy() is about to free. A persistent BH can be deleted during destruction, cancelling any pending schedule.

Message-ID: <[email protected]>

---
 monitor/monitor-internal.h |  2 +-
 monitor/monitor.c          | 25 ++++++++++++++-----------
 2 files changed, 15 insertions(+), 12 deletions(-)
monitor/monitor-internal.h +1 -1
index 012d442a20..a82e1aacb6 100644
@@ -134,7 +134,7 @@ struct Monitor {
     char *chardev_id;
     CharFrontend chr;
     int suspend_cnt;            /* Needs to be accessed atomically */
-
+    QEMUBH *accept_input_bh;    /* persistent BH for monitor_accept_input */
     char *mon_cpu_path;
     QTAILQ_ENTRY(Monitor) entry;
 
monitor/monitor.c +14 -11
index f0ca6b04ed..de1f761041 100644
@@ -83,6 +83,9 @@ static void monitor_finalize(Object *obj)
 {
     Monitor *mon = MONITOR(obj);
 
+    if (mon->accept_input_bh) {
+        qemu_bh_delete(mon->accept_input_bh);
+    }
     g_free(mon->chardev_id);
     g_free(mon->mon_cpu_path);
     qemu_chr_fe_deinit(&mon->chr, false);
@@ -569,15 +572,7 @@ static void monitor_accept_input(void *opaque)
 void monitor_resume(Monitor *mon)
 {
     if (qatomic_dec_fetch(&mon->suspend_cnt) == 0) {
-        AioContext *ctx;
-
-        if (monitor_requires_iothread(mon)) {
-            ctx = iothread_get_aio_context(mon_iothread);
-        } else {
-            ctx = qemu_get_aio_context();
-        }
-
-        aio_bh_schedule_oneshot(ctx, monitor_accept_input, mon);
+        qemu_bh_schedule(mon->accept_input_bh);
     }
 
     trace_monitor_suspend(mon, -1);
@@ -700,6 +695,7 @@ char *monitor_compat_id(void)
 static void monitor_complete(UserCreatable *uc, Error **errp)
 {
     Monitor *mon = MONITOR(uc);
+    AioContext *ctx;
 
     if (mon->chardev_id) {
         Chardev *chr = qemu_chr_find(mon->chardev_id);
@@ -713,9 +709,16 @@ static void monitor_complete(UserCreatable *uc, Error **errp)
         }
     }
 
-    if (monitor_requires_iothread(mon) && !mon_iothread) {
-        mon_iothread = iothread_create("mon_iothread", &error_abort);
+    if (monitor_requires_iothread(mon)) {
+        if (!mon_iothread) {
+            mon_iothread = iothread_create("mon_iothread", &error_abort);
+        }
+
+        ctx = iothread_get_aio_context(mon_iothread);
+    } else {
+        ctx = qemu_get_aio_context();
     }
+    mon->accept_input_bh = aio_bh_new(ctx, monitor_accept_input, mon);
 }
 
 int monitor_new(MonitorOptions *opts, bool allow_hmp, Error **errp)
Signature · 1 line
2.54.0
#14 lore raw

[PULL 28/35] tests/qtest: add tests for dynamic monitor add/remove

In reply to Markus Armbruster

From: Christian Brauner <[email protected]>

Test the object-add/object-del QMP commands with the monitor-qmp object type.

- Basic lifecycle: chardev-add -> object-add -> object-del -> chardev-remove
- Error: object-add with nonexistent chardev
- Error: second monitor on same chardev (chardev already in use)
- Removal of CLI-created QMP monitor succeeds
- Error: object-remove on HMP monitor
- Re-add after remove: same id and chardev reusable after removal

[DB: modified to use object-add/object-del, removing redundant
scenarios already handled by object-add/del code]

Message-ID: <[email protected]>

---
 tests/qtest/qmp-test.c | 174 +++++++++++++++++++++++++++++++++++++++++
 1 file changed, 174 insertions(+)
tests/qtest/qmp-test.c +174 -0
index edf0886787..3a325a04e0 100644
@@ -337,6 +337,174 @@ static void test_qmp_missing_any_arg(void)
     qtest_quit(qts);
 }
 
+static void test_qmp_monitor_add_remove(void)
+{
+    QTestState *qts;
+    QDict *resp;
+
+    qts = qtest_init(common_args);
+
+    /* Create a null chardev for the dynamic monitor */
+    resp = qtest_qmp(qts,
+                     "{'execute': 'chardev-add',"
+                     " 'arguments': {'id': 'monitor-chardev',"
+                     "               'backend': {'type': 'null',"
+                     "                           'data': {}}}}");
+    g_assert(qdict_haskey(resp, "return"));
+    qobject_unref(resp);
+
+    /* Add a dynamic monitor */
+    resp = qtest_qmp(qts,
+                     "{'execute': 'object-add',"
+                     " 'arguments': {'qom-type': 'monitor-qmp',"
+                     "               'id': 'dyn-mon',"
+                     "               'chardev': 'monitor-chardev'}}");
+    g_assert(qdict_haskey(resp, "return"));
+    qobject_unref(resp);
+
+    /* Remove the dynamic monitor */
+    resp = qtest_qmp(qts,
+                     "{'execute': 'object-del',"
+                     " 'arguments': {'id': 'dyn-mon'}}");
+    g_assert(qdict_haskey(resp, "return"));
+    qobject_unref(resp);
+
+    /* Add again after remove -- same id and chardev should work */
+    resp = qtest_qmp(qts,
+                     "{'execute': 'object-add',"
+                     " 'arguments': {'qom-type': 'monitor-qmp',"
+                     "               'id': 'dyn-mon',"
+                     "               'chardev': 'monitor-chardev'}}");
+    g_assert(qdict_haskey(resp, "return"));
+    qobject_unref(resp);
+
+    /* Clean up */
+    resp = qtest_qmp(qts,
+                     "{'execute': 'object-del',"
+                     " 'arguments': {'id': 'dyn-mon'}}");
+    g_assert(qdict_haskey(resp, "return"));
+    qobject_unref(resp);
+
+    resp = qtest_qmp(qts,
+                     "{'execute': 'chardev-remove',"
+                     " 'arguments': {'id': 'monitor-chardev'}}");
+    g_assert(qdict_haskey(resp, "return"));
+    qobject_unref(resp);
+
+    qtest_quit(qts);
+}
+
+static void test_qmp_monitor_error_paths(void)
+{
+    QTestState *qts;
+    QDict *resp;
+
+    qts = qtest_init(common_args);
+
+    /* Error: chardev does not exist */
+    resp = qtest_qmp(qts,
+                     "{'execute': 'object-add',"
+                     " 'arguments': {'qom-type': 'monitor-qmp',"
+                     "               'id': 'bad-mon',"
+                     "               'chardev': 'nonexistent'}}");
+    qmp_expect_error_and_unref(resp, "GenericError");
+
+    qtest_quit(qts);
+}
+
+static void test_qmp_monitor_chardev_in_use(void)
+{
+    QTestState *qts;
+    QDict *resp;
+
+    qts = qtest_init(common_args);
+
+    /* Create a null chardev */
+    resp = qtest_qmp(qts,
+                     "{'execute': 'chardev-add',"
+                     " 'arguments': {'id': 'shared-chr',"
+                     "               'backend': {'type': 'null',"
+                     "                           'data': {}}}}");
+    g_assert(qdict_haskey(resp, "return"));
+    qobject_unref(resp);
+
+    /* Attach first monitor */
+    resp = qtest_qmp(qts,
+                     "{'execute': 'object-add',"
+                     " 'arguments': {'qom-type': 'monitor-qmp',"
+                     "               'id': 'mon-1',"
+                     "               'chardev': 'shared-chr'}}");
+    g_assert(qdict_haskey(resp, "return"));
+    qobject_unref(resp);
+
+    /* Error: second monitor on the same chardev */
+    resp = qtest_qmp(qts,
+                     "{'execute': 'object-add',"
+                     " 'arguments': {'qom-type': 'monitor-qmp',"
+                     "               'id': 'mon-2',"
+                     "               'chardev': 'shared-chr'}}");
+    qmp_expect_error_and_unref(resp, "GenericError");
+
+    /* Clean up */
+    resp = qtest_qmp(qts,
+                     "{'execute': 'object-del',"
+                     " 'arguments': {'id': 'mon-1'}}");
+    g_assert(qdict_haskey(resp, "return"));
+    qobject_unref(resp);
+
+    resp = qtest_qmp(qts,
+                     "{'execute': 'chardev-remove',"
+                     " 'arguments': {'id': 'shared-chr'}}");
+    g_assert(qdict_haskey(resp, "return"));
+    qobject_unref(resp);
+
+    qtest_quit(qts);
+}
+
+static void test_qmp_monitor_remove_cli(void)
+{
+    QTestState *qts;
+    QDict *resp;
+
+    /* Launch with a named CLI monitor on a null chardev */
+    qts = qtest_initf("%s -chardev null,id=cli-chr"
+                      " -object monitor-qmp,id=cli-mon,chardev=cli-chr",
+                      common_args);
+
+    /* CLI-created QMP monitors can be removed */
+    resp = qtest_qmp(qts,
+                     "{'execute': 'object-del',"
+                     " 'arguments': {'id': 'cli-mon'}}");
+    g_assert(qdict_haskey(resp, "return"));
+    qobject_unref(resp);
+
+    resp = qtest_qmp(qts,
+                     "{'execute': 'chardev-remove',"
+                     " 'arguments': {'id': 'cli-chr'}}");
+    g_assert(qdict_haskey(resp, "return"));
+    qobject_unref(resp);
+
+    qtest_quit(qts);
+}
+
+static void test_qmp_monitor_remove_hmp(void)
+{
+    QTestState *qts;
+    QDict *resp;
+
+    qts = qtest_initf("%s -chardev null,id=hmp-chr"
+                      " -object monitor-hmp,id=hmp-mon,chardev=hmp-chr",
+                      common_args);
+
+    /* Error: object_del must reject HMP monitors */
+    resp = qtest_qmp(qts,
+                     "{'execute': 'object-del',"
+                     " 'arguments': {'id': 'hmp-mon'}}");
+    qmp_expect_error_and_unref(resp, "GenericError");
+
+    qtest_quit(qts);
+}
+
 int main(int argc, char *argv[])
 {
     g_test_init(&argc, &argv, NULL);
@@ -348,6 +516,12 @@ int main(int argc, char *argv[])
 #endif
     qtest_add_func("qmp/preconfig", test_qmp_preconfig);
     qtest_add_func("qmp/missing-any-arg", test_qmp_missing_any_arg);
+    qtest_add_func("qmp/monitor-add-remove", test_qmp_monitor_add_remove);
+    qtest_add_func("qmp/monitor-error-paths", test_qmp_monitor_error_paths);
+    qtest_add_func("qmp/monitor-chardev-in-use",
+                    test_qmp_monitor_chardev_in_use);
+    qtest_add_func("qmp/monitor-remove-cli", test_qmp_monitor_remove_cli);
+    qtest_add_func("qmp/monitor-remove-hmp", test_qmp_monitor_remove_hmp);
 
     return g_test_run();
 }
Signature · 1 line
2.54.0
#15 lore raw

[PULL 01/35] qom: replace 'can_be_deleted' with 'prepare_delete'

In reply to Markus Armbruster

From: Daniel P. Berrangé <[email protected]>

While most objects can perform all their cleanup in the finalizer method, there can be interactions with other resources / subsystems / threads which require that some cleanup be performed on an user creatable object before unparenting it and entering finalization.

The current 'can_be_deleted' method runs in the deletion path and is intended to be used to block deletion. While it could be used to perform cleanup tasks, its name suggests it should be free of side-effects.

Generalize this by renaming it to 'prepare_delete', explicitly allowing for cleanup to be provided. Existing users of 'can_be_deleted' are re-written, which provides them with more detailed/tailored error messages.

Message-ID: <[email protected]>

---
 include/qom/object_interfaces.h  | 26 +++++++++++++++++---------
 include/system/event-loop-base.h |  2 +-
 backends/cryptodev.c             | 12 +++++++++---
 backends/hostmem.c               |  7 +++++--
 backends/iommufd.c               | 11 ++++++++---
 block/throttle-groups.c          | 12 +++++++++---
 event-loop-base.c                |  8 ++++----
 net/can/can_core.c               |  6 ++++--
 qom/object_interfaces.c          | 13 +++++--------
 util/main-loop.c                 |  6 ++++--
 tests/qemu-iotests/245           |  4 ++--
 11 files changed, 68 insertions(+), 39 deletions(-)
include/qom/object_interfaces.h +17 -9
index e2b8615617..afd0fb93b2 100644
@@ -20,8 +20,10 @@ typedef struct UserCreatable UserCreatable;
  * UserCreatableClass:
  * @parent_class: the base class
  * @complete: callback to be called after @obj's properties are set.
- * @can_be_deleted: callback to be called before an object is removed
- * to check if @obj can be removed safely.
+ * @prepare_delete: to be called before an attempt to delete @obj
+ * to validate whether the object can be deleted and trigger any
+ * cleanup of any resources which have to be dealt with before the
+ * object is unparented and enters finalization.
  *
  * Interface is designed to work with -object/object-add/object_add
  * commands.
@@ -36,7 +38,9 @@ typedef struct UserCreatable UserCreatable;
  * For objects created without using -object/object-add/object_add,
  * @user_creatable_complete() wrapper should be called manually if
  * object's type implements USER_CREATABLE interface and needs
- * complete() callback to be called.
+ * complete() callback to be called. Similarly @user_creatable_prepare_delete()
+ * should be called manually prior to an attempt to the delete the
+ * object.
  */
 struct UserCreatableClass {
     /* <private> */
@@ -44,7 +48,7 @@ struct UserCreatableClass {
 
     /* <public> */
     void (*complete)(UserCreatable *uc, Error **errp);
-    bool (*can_be_deleted)(UserCreatable *uc);
+    bool (*prepare_delete)(UserCreatable *uc, Error **errp);
 };
 
 /**
@@ -61,13 +65,17 @@ struct UserCreatableClass {
 bool user_creatable_complete(UserCreatable *uc, Error **errp);
 
 /**
- * user_creatable_can_be_deleted:
- * @uc: the object whose can_be_deleted() method is called if implemented
+ * user_creatable_prepare_delete:
+ * @uc: the user-creatable object whose prepare_delete() method is called
+ * @errp: if an error occurs, a pointer to an area to store the error
  *
- * Wrapper to call can_be_deleted() method if one of types it's inherited
- * from implements USER_CREATABLE interface.
+ * Wrapper to call prepare_delete() class method if defined, otherwise
+ * does nothing.
+ *
+ * Returns: %true on success or if prepare_delete() is not defined,
+ *          %false on failure.
  */
-bool user_creatable_can_be_deleted(UserCreatable *uc);
+bool user_creatable_prepare_delete(UserCreatable *uc, Error **errp);
 
 /**
  * user_creatable_add_qapi:
include/system/event-loop-base.h +1 -1
index 130629e7f3..1e1e427ac7 100644
@@ -24,7 +24,7 @@ struct EventLoopBaseClass {
 
     void (*init)(EventLoopBase *base, Error **errp);
     void (*update_params)(EventLoopBase *base, Error **errp);
-    bool (*can_be_deleted)(EventLoopBase *base);
+    bool (*prepare_delete)(EventLoopBase *base, Error **errp);
 };
 
 struct EventLoopBase {
backends/cryptodev.c +9 -3
index 79f8882d3b..e8f2b18f20 100644
@@ -454,9 +454,15 @@ bool cryptodev_backend_is_ready(CryptoDevBackend *backend)
 }
 
 static bool
-cryptodev_backend_can_be_deleted(UserCreatable *uc)
+cryptodev_backend_prepare_delete(UserCreatable *uc, Error **errp)
 {
-    return !cryptodev_backend_is_used(CRYPTODEV_BACKEND(uc));
+    if (cryptodev_backend_is_used(CRYPTODEV_BACKEND(uc))) {
+        error_setg(errp,
+                   "Cannot delete cryptodev backend '%s' that is in use",
+                   object_get_canonical_path_component(OBJECT(uc)));
+        return false;
+    }
+    return true;
 }
 
 static void cryptodev_backend_instance_init(Object *obj)
@@ -613,7 +619,7 @@ cryptodev_backend_class_init(ObjectClass *oc, const void *data)
     UserCreatableClass *ucc = USER_CREATABLE_CLASS(oc);
 
     ucc->complete = cryptodev_backend_complete;
-    ucc->can_be_deleted = cryptodev_backend_can_be_deleted;
+    ucc->prepare_delete = cryptodev_backend_prepare_delete;
 
     QTAILQ_INIT(&crypto_clients);
     object_class_property_add(oc, "queues", "uint32",
backends/hostmem.c +5 -2
index cd2085fb3c..5dd5fb155c 100644
@@ -434,9 +434,12 @@ host_memory_backend_memory_complete(UserCreatable *uc, Error **errp)
 }
 
 static bool
-host_memory_backend_can_be_deleted(UserCreatable *uc)
+host_memory_backend_prepare_delete(UserCreatable *uc, Error **errp)
 {
     if (host_memory_backend_is_mapped(MEMORY_BACKEND(uc))) {
+        error_setg(errp,
+                   "Cannot delete host memory backend '%s' which is mapped",
+                   object_get_canonical_path_component(OBJECT(uc)));
         return false;
     } else {
         return true;
@@ -508,7 +511,7 @@ host_memory_backend_class_init(ObjectClass *oc, const void *data)
     UserCreatableClass *ucc = USER_CREATABLE_CLASS(oc);
 
     ucc->complete = host_memory_backend_memory_complete;
-    ucc->can_be_deleted = host_memory_backend_can_be_deleted;
+    ucc->prepare_delete = host_memory_backend_prepare_delete;
 
     object_class_property_add_bool(oc, "merge",
         host_memory_backend_get_merge,
backends/iommufd.c +8 -3
index 09624cd652..0643947140 100644
@@ -63,11 +63,16 @@ static void iommufd_backend_set_fd(Object *obj, const char *str, Error **errp)
     trace_iommu_backend_set_fd(be->fd);
 }
 
-static bool iommufd_backend_can_be_deleted(UserCreatable *uc)
+static bool iommufd_backend_prepare_delete(UserCreatable *uc, Error **errp)
 {
     IOMMUFDBackend *be = IOMMUFD_BACKEND(uc);
 
-    return !be->users;
+    if (be->users) {
+        error_setg(errp, "Can not delete IOMMUFD backend '%s' with %d users",
+                   object_get_canonical_path_component(OBJECT(uc)), be->users);
+        return false;
+    }
+    return true;
 }
 
 static void iommufd_backend_complete(UserCreatable *uc, Error **errp)
@@ -92,7 +97,7 @@ static void iommufd_backend_class_init(ObjectClass *oc, const void *data)
 {
     UserCreatableClass *ucc = USER_CREATABLE_CLASS(oc);
 
-    ucc->can_be_deleted = iommufd_backend_can_be_deleted;
+    ucc->prepare_delete = iommufd_backend_prepare_delete;
     ucc->complete = iommufd_backend_complete;
 
     object_class_property_add_str(oc, "fd", NULL, iommufd_backend_set_fd);
block/throttle-groups.c +9 -3
index 4b1b1944c2..805e47270c 100644
@@ -960,9 +960,15 @@ static void throttle_group_get_limits(Object *obj, Visitor *v,
     visit_type_ThrottleLimits(v, name, &argp, errp);
 }
 
-static bool throttle_group_can_be_deleted(UserCreatable *uc)
+static bool throttle_group_prepare_delete(UserCreatable *uc, Error **errp)
 {
-    return OBJECT(uc)->ref == 1;
+    if (OBJECT(uc)->ref > 1) {
+        error_setg(errp,
+                   "Cannot delete throttle group '%s' with active references",
+                   object_get_canonical_path_component(OBJECT(uc)));
+        return false;
+    }
+    return true;
 }
 
 static void throttle_group_obj_class_init(ObjectClass *klass,
@@ -972,7 +978,7 @@ static void throttle_group_obj_class_init(ObjectClass *klass,
     UserCreatableClass *ucc = USER_CREATABLE_CLASS(klass);
 
     ucc->complete = throttle_group_obj_complete;
-    ucc->can_be_deleted = throttle_group_can_be_deleted;
+    ucc->prepare_delete = throttle_group_prepare_delete;
 
     /* individual properties */
     for (i = 0; i < sizeof(properties) / sizeof(ThrottleParamInfo); i++) {
event-loop-base.c +4 -4
index 8ca143bea4..ee5987ddbf 100644
@@ -85,13 +85,13 @@ static void event_loop_base_complete(UserCreatable *uc, Error **errp)
     }
 }
 
-static bool event_loop_base_can_be_deleted(UserCreatable *uc)
+static bool event_loop_base_prepare_delete(UserCreatable *uc, Error **errp)
 {
     EventLoopBaseClass *bc = EVENT_LOOP_BASE_GET_CLASS(uc);
     EventLoopBase *backend = EVENT_LOOP_BASE(uc);
 
-    if (bc->can_be_deleted) {
-        return bc->can_be_deleted(backend);
+    if (bc->prepare_delete) {
+        return bc->prepare_delete(backend, errp);
     }
 
     return true;
@@ -102,7 +102,7 @@ static void event_loop_base_class_init(ObjectClass *klass,
 {
     UserCreatableClass *ucc = USER_CREATABLE_CLASS(klass);
     ucc->complete = event_loop_base_complete;
-    ucc->can_be_deleted = event_loop_base_can_be_deleted;
+    ucc->prepare_delete = event_loop_base_prepare_delete;
 
     object_class_property_add(klass, "aio-max-batch", "int",
                               event_loop_base_get_param,
net/can/can_core.c +4 -2
index 77fe2b8ba4..6a56b33251 100644
@@ -143,8 +143,10 @@ int can_bus_client_set_filters(CanBusClientState *client,
 }
 
 
-static bool can_bus_can_be_deleted(UserCreatable *uc)
+static bool can_bus_prepare_delete(UserCreatable *uc, Error **errp)
 {
+    error_setg(errp, "Deleting CAN bus device '%s' is not supported",
+               object_get_canonical_path_component(OBJECT(uc)));
     return false;
 }
 
@@ -153,7 +155,7 @@ static void can_bus_class_init(ObjectClass *klass,
 {
     UserCreatableClass *uc_klass = USER_CREATABLE_CLASS(klass);
 
-    uc_klass->can_be_deleted = can_bus_can_be_deleted;
+    uc_klass->prepare_delete = can_bus_prepare_delete;
 }
 
 static const TypeInfo can_bus_info = {
qom/object_interfaces.c +5 -8
index 7080f85f95..3216a754ed 100644
@@ -32,16 +32,14 @@ bool user_creatable_complete(UserCreatable *uc, Error **errp)
     return !*errp;
 }
 
-bool user_creatable_can_be_deleted(UserCreatable *uc)
+bool user_creatable_prepare_delete(UserCreatable *uc, Error **errp)
 {
-
     UserCreatableClass *ucc = USER_CREATABLE_GET_CLASS(uc);
 
-    if (ucc->can_be_deleted) {
-        return ucc->can_be_deleted(uc);
-    } else {
-        return true;
+    if (ucc->prepare_delete) {
+        return ucc->prepare_delete(uc, errp);
     }
+    return true;
 }
 
 void user_creatable_add_qapi(ObjectOptions *options, Error **errp)
@@ -253,8 +251,7 @@ bool user_creatable_del(const char *id, Error **errp)
         return false;
     }
 
-    if (!user_creatable_can_be_deleted(USER_CREATABLE(obj))) {
-        error_setg(errp, "object '%s' is in use, can not be deleted", id);
+    if (!user_creatable_prepare_delete(USER_CREATABLE(obj), errp)) {
         return false;
     }
 
util/main-loop.c +4 -2
index ad8645c30a..65e5dbcc94 100644
@@ -218,8 +218,10 @@ static void main_loop_init(EventLoopBase *base, Error **errp)
     mloop = m;
 }
 
-static bool main_loop_can_be_deleted(EventLoopBase *base)
+static bool main_loop_prepare_delete(EventLoopBase *base, Error **errp)
 {
+    error_setg(errp, "Deleting main loop '%s' is not supported",
+               object_get_canonical_path_component(OBJECT(base)));
     return false;
 }
 
@@ -229,7 +231,7 @@ static void main_loop_class_init(ObjectClass *oc, const void *class_data)
 
     bc->init = main_loop_init;
     bc->update_params = main_loop_update_params;
-    bc->can_be_deleted = main_loop_can_be_deleted;
+    bc->prepare_delete = main_loop_prepare_delete;
 }
 
 static const TypeInfo main_loop_info = {
tests/qemu-iotests/245 +2 -2
index f96610f510..03550b9971 100755
@@ -801,7 +801,7 @@ class TestBlockdevReopen(iotests.QMPTestCase):
         # Now group1 is in use, it cannot be deleted
         result = self.vm.qmp('object-del', id = 'group1')
         self.assert_qmp(result, 'error/class', 'GenericError')
-        self.assert_qmp(result, 'error/desc', "object 'group1' is in use, can not be deleted")
+        self.assert_qmp(result, 'error/desc', "Cannot delete throttle group 'group1' with active references")
 
         # Default options, this switches the group back to group0
         self.reopen(opts)
@@ -809,7 +809,7 @@ class TestBlockdevReopen(iotests.QMPTestCase):
         # So now we cannot delete group0
         result = self.vm.qmp('object-del', id = 'group0')
         self.assert_qmp(result, 'error/class', 'GenericError')
-        self.assert_qmp(result, 'error/desc', "object 'group0' is in use, can not be deleted")
+        self.assert_qmp(result, 'error/desc', "Cannot delete throttle group 'group0' with active references")
 
         # But group1 is free this time, and it can be deleted
         self.vm.cmd('object-del', id = 'group1')
Signature · 1 line
2.54.0
#16 lore raw

[PULL 21/35] monitor: drop unused monitor_is_qmp method

In reply to Markus Armbruster

From: Daniel P. Berrangé <[email protected]>

The previous patch dropped the only remaining use of monitor_is_qmp.

Message-ID: <[email protected]>

---
 monitor/monitor-internal.h | 9 ---------
 monitor/monitor.c          | 1 -
 2 files changed, 10 deletions(-)
monitor/monitor-internal.h +0 -9
index efd21b8912..fe5703af6d 100644
@@ -134,7 +134,6 @@ struct Monitor {
     char *chardev_id;
     CharFrontend chr;
     int suspend_cnt;            /* Needs to be accessed atomically */
-    bool is_qmp;
 
     char *mon_cpu_path;
     QTAILQ_ENTRY(Monitor) entry;
@@ -197,14 +196,6 @@ struct MonitorQMP {
     GQueue *qmp_requests;
 };
 
-/**
- * Is @mon a QMP monitor?
- */
-static inline bool monitor_is_qmp(const Monitor *mon)
-{
-    return mon->is_qmp;
-}
-
 typedef QTAILQ_HEAD(MonitorList, Monitor) MonitorList;
 extern IOThread *mon_iothread;
 extern Coroutine *qmp_dispatcher_co;
monitor/monitor.c +0 -1
index 6fdd0255f4..9b62716033 100644
@@ -115,7 +115,6 @@ static void monitor_init(Object *obj)
     Monitor *mon = MONITOR(obj);
 
     qemu_mutex_init(&mon->mon_lock);
-    mon->is_qmp = !!object_dynamic_cast(obj, TYPE_MONITOR_QMP);
     mon->outbuf = g_string_new(NULL);
 }
 
Signature · 1 line
2.54.0
#17 lore raw

[PULL 05/35] monitor: minimal conversion of monitors to QOM

In reply to Markus Armbruster

From: Daniel P. Berrangé <[email protected]>

This introduces abstract QOM type "monitor", with concrete subtypes "monitor-hmp" and "monitor-qmp". This is the bare minimum conversion of just the type declarations and replacing g_new/g_free with object_new/object_unref.

Command line option "-monitor" now creates a "monitor-hmp" object "/objects/compat_monitorNNN" in addition to the character device "/chardevs/compat_monitorNNN". NNN counts up from zero.

Exception: "-monitor chardev:ID" creates a "monitor-hmp" object "/objects/ID", and does not create a character device.

"-qmp" and "-qmp-pretty" work the same, except they create a "monitor-qmp" object.

"-mon" now creates either a "monitor-hmp" or "monitor-qmp" object "/objects/ID" if the option argument provides an ID, else "/objects/compat_monitorNNN".

"-gdbstub" and "-serial mon:..." now create a "monitor-hmp" object "/objects/compat_monitorNNN".

Note that the object's name in "/objects/" matches the QemuOpts ID when it exists. The only cases where it doesn't exist are "-mon" without ID, "-gdbstub" and "-serial mon:".

A future patch will make "monitor-hmp" and "monitor-qmp" work with "-object" and "object-add".

Note: there is a slight change in the NNN values assigned. The old code would increment the counter for every monitor added (except for -mon, -serial mon:..., -gdbstub), regardless of whether it needed a "compat_monitorNNN" ID assignment. Now it is only incremented when an automatic ID assigned is needed (but even for -mon, -serial mon:..., -gdbstub).

Message-ID: <[email protected]>

[Commit message made slightly more precise]
---
 include/monitor/monitor.h  | 18 +++++++++++++++---
 monitor/monitor-internal.h | 18 ++++++++++++++++--
 chardev/char.c             |  2 +-
 gdbstub/system.c           |  2 +-
 monitor/hmp.c              | 31 ++++++++++++++++++++++++++++---
 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(-)
include/monitor/monitor.h +15 -3
index b9642b58ba..83723f705a 100644
@@ -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);
 
-typedef struct MonitorHMP MonitorHMP;
 typedef struct MonitorOptions MonitorOptions;
 
 #define QMP_REQ_QUEUE_LEN_MAX 8
@@ -19,8 +28,11 @@ bool monitor_cur_is_qmp(void);
 
 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);
monitor/monitor-internal.h +16 -2
index 4da2b2a677..05c1f2f5e0 100644
@@ -101,7 +101,13 @@ typedef struct HMPCommand {
     bool coroutine;
 } HMPCommand;
 
+
+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;
 };
 
+struct MonitorHMPClass {
+    MonitorClass parent_class;
+};
+
 struct MonitorHMP {
     Monitor parent_obj;
     bool use_readline;
@@ -140,7 +150,11 @@ struct MonitorHMP {
     ReadLineState *rs;
 };
 
-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;
+};
 
 /**
  * Is @mon a QMP monitor?
chardev/char.c +1 -1
index 813c04d953..c71ffa7963 100644
@@ -805,7 +805,7 @@ static Chardev *qemu_chr_new_from_name(const char *label, const char *filename,
 
     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);
         if (err) {
             error_report_err(err);
             object_unparent(OBJECT(chr));
gdbstub/system.c +1 -1
index 03e088b17d..e51d32fa65 100644
@@ -390,7 +390,7 @@ bool gdbserver_start(const char *device, Error **errp)
         /* Initialize a monitor terminal for gdb */
         mon_chr = 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);
     } else {
         qemu_chr_fe_deinit(&gdbserver_system_state.chr, true);
         mon_chr = gdbserver_system_state.mon_chr;
monitor/hmp.c +28 -3
index 4e4468424a..da11e56854 100644
@@ -43,6 +43,20 @@
 #include "system/block-backend.h"
 #include "trace.h"
 
+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);
 }
 
-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 = g_new0(MonitorHMP, 1);
+    MonitorHMP *mon;
+    g_autofree char *autoid = id ? NULL : monitor_compat_id();
+    Object *obj = object_new_with_props(TYPE_MONITOR_HMP,
+                                        object_get_objects_root(),
+                                        id ? id : autoid,
+                                        errp,
+                                        NULL);
+    if (!obj) {
+        return;
+    }
+    mon = MONITOR_HMP(obj);
 
     if (!qemu_chr_fe_init(&mon->parent_obj.chr, chr, errp)) {
-        g_free(mon);
+        object_unparent(OBJECT(mon));
         return;
     }
 
monitor/monitor.c +27 -4
index a87597e606..18a1d8ddde 100644
@@ -73,6 +73,22 @@ static GHashTable *coroutine_mon; /* Maps Coroutine* to Monitor* */
 MonitorList mon_list;
 static bool monitor_destroyed;
 
+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)
 
     if (mon) {
         monitor_data_destroy(mon);
-        g_free(mon);
+        object_unparent(OBJECT(mon));
     }
 }
 
@@ -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);
 
@@ -715,6 +731,13 @@ void monitor_init_globals(void)
     aio_co_schedule(iohandler_get_aio_context(), qmp_dispatcher_co);
 }
 
+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)
 
     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 monitors");
             return -1;
         }
-        monitor_new_hmp(chr, true, errp);
+        monitor_new_hmp(opts->id, chr, true, errp);
         break;
     default:
         g_assert_not_reached();
monitor/qmp-cmds.c +8 -7
index aa9ee8a391..bfde769ef0 100644
@@ -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 = NULL;
-    MonitorHMP hmp = {};
+    MonitorHMP *hmp = MONITOR_HMP(object_new(TYPE_MONITOR_HMP));
 
-    monitor_data_init(&hmp.parent_obj, false, true, false);
+    monitor_data_init(&hmp->parent_obj, false, true, false);
 
     if (has_cpu_index) {
-        int ret = monitor_set_cpu(&hmp.parent_obj, cpu_index);
+        int ret = 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,
         }
     }
 
-    handle_hmp_command(&hmp, command_line);
+    handle_hmp_command(hmp, command_line);
 
-    WITH_QEMU_LOCK_GUARD(&hmp.parent_obj.mon_lock) {
-        output = g_strdup(hmp.parent_obj.outbuf->str);
+    WITH_QEMU_LOCK_GUARD(&hmp->parent_obj.mon_lock) {
+        output = g_strdup(hmp->parent_obj.outbuf->str);
     }
 
 out:
-    monitor_data_destroy(&hmp.parent_obj);
+    monitor_data_destroy(&hmp->parent_obj);
+    object_unref(hmp);
     return output;
 }
 
monitor/qmp.c +28 -3
index cb28a95efd..1ef09352fc 100644
@@ -71,6 +71,20 @@ typedef struct QMPRequest QMPRequest;
 
 QmpCommandList qmp_commands, qmp_cap_negotiation_commands;
 
+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 *opaque)
     monitor_list_append(&mon->parent_obj);
 }
 
-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 = g_new0(MonitorQMP, 1);
+    MonitorQMP *mon;
+    g_autofree char *autoid = id ? NULL : monitor_compat_id();
+    Object *obj = object_new_with_props(TYPE_MONITOR_QMP,
+                                        object_get_objects_root(),
+                                        id ? id : autoid,
+                                        errp,
+                                        NULL);
+    if (!obj) {
+        return;
+    }
+    mon = MONITOR_QMP(obj);
 
     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);
stubs/monitor-internal.c +2 -1
index 23d58da184..20367b7e9a 100644
@@ -8,6 +8,7 @@ int monitor_get_fd(Monitor *mon, const char *name, Error **errp)
     return -1;
 }
 
-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)
 {
 }
system/vl.c +3 -4
index 6643242729..4737c03872 100644
@@ -1252,7 +1252,6 @@ static int mon_init_func(void *opaque, QemuOpts *opts, Error **errp)
 
 static void monitor_parse(const char *str, const char *mode, bool pretty)
 {
-    static int monitor_device_index = 0;
     QemuOpts *opts;
     const char *p;
     char label[32];
@@ -1260,8 +1259,9 @@ static void monitor_parse(const char *str, const char *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 = monitor_compat_id();
+        assert(strlen(id) < sizeof(label));
+        memcpy(label, id, strlen(id) + 1);
         opts = 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 char *mode, bool pretty)
     } else {
         assert(pretty == false);
     }
-    monitor_device_index++;
 }
 
 struct device_config {
Signature · 1 line
2.54.0
#18 lore raw

[PULL 12/35] monitor: use class methods for monitor_vprintf

In reply to Markus Armbruster

From: Daniel P. Berrangé <[email protected]>

This removes the need for using monitor_is_qmp() to check the subclass type, which is an anti-pattern.

Message-ID: <[email protected]>

---
 monitor/monitor-internal.h |  7 +++++++
 monitor/hmp.c              | 13 +++++++++++++
 monitor/monitor.c          | 11 ++++-------
 3 files changed, 24 insertions(+), 7 deletions(-)
monitor/monitor-internal.h +7 -0
index 6a4c3b0f37..23cef68153 100644
@@ -104,6 +104,13 @@ typedef struct HMPCommand {
 
 struct MonitorClass {
     ObjectClass parent_class;
+
+    /*
+     * If non-NULL, the monitor is able to print messages
+     * for attention of the client user
+     */
+    int (*vprintf)(Monitor *mon, const char *fmt, va_list ap)
+        G_GNUC_PRINTF(2, 0);
 };
 
 struct Monitor {
monitor/hmp.c +13 -0
index c03b91782c..f9252387c4 100644
@@ -68,11 +68,18 @@ static void monitor_hmp_set_readline(Object *obj, bool val, Error **errp)
     mon->use_readline = val;
 }
 
+int monitor_hmp_vprintf(Monitor *mon, const char *fmt, va_list ap)
+    G_GNUC_PRINTF(2, 0);
+
 static void monitor_hmp_class_init(ObjectClass *cls, const void *data)
 {
+    MonitorClass *moncls = MONITOR_CLASS(cls);
+
     object_class_property_add_bool(cls, "readline",
                                    monitor_hmp_get_readline,
                                    monitor_hmp_set_readline);
+
+    moncls->vprintf = monitor_hmp_vprintf;
 }
 
 static void monitor_hmp_init(Object *obj)
@@ -87,6 +94,12 @@ static void monitor_hmp_init(Object *obj)
     hmp->use_readline = true;
 }
 
+int monitor_hmp_vprintf(Monitor *mon, const char *fmt, va_list ap)
+{
+    g_autofree char *buf = g_strdup_vprintf(fmt, ap);
+    return monitor_puts(mon, buf);
+}
+
 static void monitor_command_cb(void *opaque, const char *cmdline,
                                void *readline_opaque)
 {
monitor/monitor.c +4 -7
index 9fe131983d..0cb0930bf4 100644
@@ -264,21 +264,18 @@ int monitor_puts(Monitor *mon, const char *str)
 
 int monitor_vprintf(Monitor *mon, const char *fmt, va_list ap)
 {
-    char *buf;
-    int n;
+    MonitorClass *moncls;
 
     if (!mon) {
         return -1;
     }
 
-    if (monitor_is_qmp(mon)) {
+    moncls = MONITOR_GET_CLASS(mon);
+    if (!moncls->vprintf) {
         return -1;
     }
 
-    buf = g_strdup_vprintf(fmt, ap);
-    n = monitor_puts(mon, buf);
-    g_free(buf);
-    return n;
+    return moncls->vprintf(mon, fmt, ap);
 }
 
 int monitor_printf(Monitor *mon, const char *fmt, ...)
Signature · 1 line
2.54.0
#19 lore raw

[PULL 09/35] monitor: add 'pretty' property to QMP Monitor class

In reply to Markus Armbruster

From: Daniel P. Berrangé <[email protected]>

This determines whether the QMP JSON responses are pretty printed with newlines and indentation, or compact with no extra whitespace.

Message-ID: <[email protected]>

---
 monitor/qmp.c | 20 ++++++++++++++++++--
 1 file changed, 18 insertions(+), 2 deletions(-)
monitor/qmp.c +18 -2
index df35b530ed..d7adb9ba8b 100644
@@ -77,8 +77,25 @@ static void monitor_qmp_finalize(Object *obj)
 {
 }
 
+static bool monitor_qmp_get_pretty(Object *obj, Error **errp)
+{
+    MonitorQMP *mon = MONITOR_QMP(obj);
+
+    return mon->pretty;
+}
+
+static void monitor_qmp_set_pretty(Object *obj, bool val, Error **errp)
+{
+    MonitorQMP *mon = MONITOR_QMP(obj);
+
+    mon->pretty = val;
+}
+
 static void monitor_qmp_class_init(ObjectClass *cls, const void *data)
 {
+    object_class_property_add_bool(cls, "pretty",
+                                   monitor_qmp_get_pretty,
+                                   monitor_qmp_set_pretty);
 }
 
 static void monitor_qmp_init(Object *obj)
@@ -538,6 +555,7 @@ void monitor_new_qmp(const char *id, const char *chardev_id,
                                         id ? id : autoid,
                                         errp,
                                         "chardev", chardev_id,
+                                        "pretty", pretty ? "yes" : "no",
                                         NULL);
 
     if (!obj) {
@@ -558,8 +576,6 @@ void monitor_new_qmp(const char *id, const char *chardev_id,
                       qemu_chr_has_feature(mon->parent_obj.chr.chr,
                                            QEMU_CHAR_FEATURE_GCONTEXT));
 
-    mon->pretty = pretty;
-
     qemu_mutex_init(&mon->qmp_queue_lock);
     mon->qmp_requests = g_queue_new();
 
Signature · 1 line
2.54.0
#20 lore raw

[PULL 23/35] monitor: implement "user creatable" interface for adding monitors

In reply to Markus Armbruster

From: Daniel P. Berrangé <[email protected]>

Implement the user creatable QOM interface and define the monitor-qmp and monitor-hmp types in QAPI. This unlocks the ability to create them on the command line with -object or in HMP/QMP with object_add.

For example:

$QEMU -chardev stdio,id=monchr0 -object monitor-hmp,id=mon0,chrdev=monchr0

Initially the "prepare_delete" callback is hardcoded to return an error which means -object and object_add can be used, but object_del will fail. Support for deleting monitors will be introduced in subsequent commits.

Message-ID: <[email protected]>

---
 qapi/qom.json              | 43 +++++++++++++++++++++++
 monitor/monitor-internal.h |  1 -
 monitor/hmp.c              | 72 ++++++++++++++++++++++++--------------
 monitor/monitor.c          | 14 ++++++--
 monitor/qmp.c              | 45 ++++++++++++++++--------
 stubs/monitor-internal.c   |  1 +
 system/vl.c                |  8 ++++-
 7 files changed, 138 insertions(+), 46 deletions(-)
qapi/qom.json +43 -0
index dd45ac1087..33a827b9fa 100644
@@ -1187,6 +1187,45 @@
   'data': { '*cpu-affinity': ['uint16'],
             '*node-affinity': ['uint16'] } }
 
+##
+# @MonitorProperties:
+#
+# Properties for all monitors
+#
+# @chardev: ID of the character device providing the monitor transport
+#
+# Since: 11.1
+##
+{ 'struct': 'MonitorProperties',
+  'data': { 'chardev': 'str' }}
+
+##
+# @MonitorHMPProperties:
+#
+# Properties for the HMP monitor
+#
+# @readline: whether to enable readline for line editing
+#      (default: true)
+#
+# Since: 11.1
+##
+{ 'struct': 'MonitorHMPProperties',
+  'base': 'MonitorProperties',
+  'data': { '*readline': 'bool' } }
+
+##
+# @MonitorQMPProperties:
+#
+# Properties for the QMP monitor
+#
+# @pretty: whether to pretty print JSON responses (default: false)
+#
+# Since: 11.1
+##
+{ 'struct': 'MonitorQMPProperties',
+  'base': 'MonitorProperties',
+  'data': { '*pretty': 'bool' } }
+
 ##
 # @ObjectType:
 #
@@ -1237,6 +1276,8 @@
     'memory-backend-ram',
     { 'name': 'memory-backend-shm',
       'if': 'CONFIG_POSIX' },
+    'monitor-hmp',
+    'monitor-qmp',
     'pef-guest',
     { 'name': 'pr-manager-helper',
       'if': 'CONFIG_LINUX' },
@@ -1315,6 +1356,8 @@
       'memory-backend-ram':         'MemoryBackendProperties',
       'memory-backend-shm':         { 'type': 'MemoryBackendShmProperties',
                                       'if': 'CONFIG_POSIX' },
+      'monitor-hmp':                'MonitorHMPProperties',
+      'monitor-qmp':                'MonitorQMPProperties',
       'pr-manager-helper':          { 'type': 'PrManagerHelperProperties',
                                       'if': 'CONFIG_LINUX' },
       'qtest':                      'QtestProperties',
monitor/monitor-internal.h +0 -1
index fe5703af6d..012d442a20 100644
@@ -204,7 +204,6 @@ extern QmpCommandList qmp_commands, qmp_cap_negotiation_commands;
 extern QemuMutex monitor_lock;
 extern MonitorList mon_list;
 
-void monitor_complete(Monitor *mon, Error **errp);
 bool monitor_requires_iothread(const Monitor *mon);
 int monitor_can_read(void *opaque);
 void monitor_list_append(Monitor *mon);
monitor/hmp.c +45 -27

108 lines not on this page · raw message

monitor/monitor.c +12 -2
index f1b189c1c2..f0ca6b04ed 100644
@@ -29,6 +29,7 @@
 #include "qapi/qapi-emit-events.h"
 #include "qapi/qapi-visit-control.h"
 #include "qobject/qdict.h"
+#include "qom/object_interfaces.h"
 #include "qemu/error-report.h"
 #include "qemu/option.h"
 #include "system/qtest.h"
@@ -75,7 +76,8 @@ static bool monitor_destroyed;
 
 int monitor_device_index;
 
-OBJECT_DEFINE_ABSTRACT_TYPE(Monitor, monitor, MONITOR, OBJECT);
+OBJECT_DEFINE_TYPE_EXTENDED(Monitor, monitor, MONITOR, OBJECT, true,
+                            { TYPE_USER_CREATABLE }, {});
 
 static void monitor_finalize(Object *obj)
 {
@@ -103,11 +105,17 @@ static void monitor_set_chardev_id(Object *obj, const char *str, Error **errp)
     mon->chardev_id = g_strdup(str);
 }
 
+static void monitor_complete(UserCreatable *uc, Error **errp);
+
 static void monitor_class_init(ObjectClass *cls, const void *data)
 {
+    UserCreatableClass *ucc = USER_CREATABLE_CLASS(cls);
+
     object_class_property_add_str(cls, "chardev",
                                   monitor_get_chardev_id,
                                   monitor_set_chardev_id);
+
+    ucc->complete = monitor_complete;
 }
 
 static void monitor_init(Object *obj)
@@ -689,8 +697,10 @@ char *monitor_compat_id(void)
     return g_strdup_printf("compat_monitor%d", monitor_device_index++);
 }
 
-void monitor_complete(Monitor *mon, Error **errp)
+static void monitor_complete(UserCreatable *uc, Error **errp)
 {
+    Monitor *mon = MONITOR(uc);
+
     if (mon->chardev_id) {
         Chardev *chr = qemu_chr_find(mon->chardev_id);
         if (chr == NULL) {
monitor/qmp.c +30 -15

80 lines not on this page · raw message

stubs/monitor-internal.c +1 -0
index f94b5e5c21..731fad221e 100644
@@ -11,4 +11,5 @@ int monitor_get_fd(Monitor *mon, const char *name, Error **errp)
 void monitor_new_hmp(const char *id, const char *chardev_id,
                      bool use_readline, Error **errp)
 {
+    g_assert_not_reached();
 }
system/vl.c +7 -1
index 4737c03872..63bdd06dfa 100644
@@ -1829,6 +1829,10 @@ static void object_option_add_visitor(Visitor *v)
 {
     ObjectOption *opt = g_new0(ObjectOption, 1);
     visit_type_ObjectOptions(v, NULL, &opt->opts, &error_fatal);
+    if (opt->opts->qom_type == OBJECT_TYPE_MONITOR_HMP ||
+        opt->opts->qom_type == OBJECT_TYPE_MONITOR_QMP) {
+        default_monitor = 0;
+    }
     QTAILQ_INSERT_TAIL(&object_opts, opt, next);
 }
 
@@ -1970,7 +1974,9 @@ static bool object_create_early(const char *type)
 
     /* Reason: property "chardev" */
     if (g_str_equal(type, "rng-egd") ||
-        g_str_equal(type, "qtest")) {
+        g_str_equal(type, "qtest") ||
+        g_str_equal(type, "monitor-hmp") ||
+        g_str_equal(type, "monitor-qmp")) {
         return false;
     }
 
Signature · 1 line
2.54.0
#21 lore raw

[PULL 19/35] monitor: use dynamic cast in QMP commands

In reply to Markus Armbruster

From: Daniel P. Berrangé <[email protected]>

Rather than asserting monitor_is_qmp(), use a QOM cast via MONITOR_QMP which performs an assert already.

Message-ID: <[email protected]>

---
 monitor/qmp-cmds-control.c | 12 ++----------
 1 file changed, 2 insertions(+), 10 deletions(-)
monitor/qmp-cmds-control.c +2 -10
index af6a2a118b..8fe0876a3d 100644
@@ -72,11 +72,7 @@ static bool qmp_caps_accept(MonitorQMP *mon, QMPCapabilityList *list,
 void qmp_qmp_capabilities(bool has_enable, QMPCapabilityList *enable,
                           Error **errp)
 {
-    Monitor *cur_mon = monitor_cur();
-    MonitorQMP *mon;
-
-    assert(monitor_is_qmp(cur_mon));
-    mon = container_of(cur_mon, MonitorQMP, parent_obj);
+    MonitorQMP *mon = MONITOR_QMP(monitor_cur());
 
     if (mon->commands == &qmp_commands) {
         error_set(errp, ERROR_CLASS_COMMAND_NOT_FOUND,
@@ -122,11 +118,7 @@ static void query_commands_cb(const QmpCommand *cmd, void *opaque)
 CommandInfoList *qmp_query_commands(Error **errp)
 {
     CommandInfoList *list = NULL;
-    Monitor *cur_mon = monitor_cur();
-    MonitorQMP *mon;
-
-    assert(monitor_is_qmp(cur_mon));
-    mon = container_of(cur_mon, MonitorQMP, parent_obj);
+    MonitorQMP *mon = MONITOR_QMP(monitor_cur());
 
     qmp_for_each_command(mon->commands, query_commands_cb, &list);
 
Signature · 1 line
2.54.0
#22 lore raw

[PULL 03/35] monitor: replace 'common' with 'parent_obj' in MonitorQMP

In reply to Markus Armbruster

From: Daniel P. Berrangé <[email protected]>

The field name 'parent_obj' is standard practice for QOM structs so align the QMP monitor.

Message-ID: <[email protected]>

---
 monitor/monitor-internal.h |  2 +-
 monitor/monitor.c          |  4 ++--
 monitor/qmp-cmds-control.c |  4 ++--
 monitor/qmp.c              | 40 +++++++++++++++++++-------------------
 4 files changed, 25 insertions(+), 25 deletions(-)
monitor/monitor-internal.h +1 -1
index eb301ea796..4da2b2a677 100644
@@ -141,7 +141,7 @@ struct MonitorHMP {
 };
 
 typedef struct {
-    Monitor common;
+    Monitor parent_obj;
     JSONMessageParser parser;
     bool pretty;
     /*
monitor/monitor.c +2 -2
index 2a1b511ff4..0b7b464ebe 100644
@@ -308,7 +308,7 @@ static void monitor_qapi_event_emit(QAPIEvent event, QDict *qdict)
             continue;
         }
 
-        qmp_mon = container_of(mon, MonitorQMP, common);
+        qmp_mon = container_of(mon, MonitorQMP, parent_obj);
         {
             QEMU_LOCK_GUARD(&mon->mon_lock);
             if (qmp_mon->commands == &qmp_cap_negotiation_commands) {
@@ -625,7 +625,7 @@ void monitor_data_destroy(Monitor *mon)
     g_free(mon->mon_cpu_path);
     qemu_chr_fe_deinit(&mon->chr, false);
     if (monitor_is_qmp(mon)) {
-        monitor_data_destroy_qmp(container_of(mon, MonitorQMP, common));
+        monitor_data_destroy_qmp(container_of(mon, MonitorQMP, parent_obj));
     } else {
         readline_free(container_of(mon, MonitorHMP, parent_obj)->rs);
     }
monitor/qmp-cmds-control.c +2 -2
index 150ca9f5cb..af6a2a118b 100644
@@ -76,7 +76,7 @@ void qmp_qmp_capabilities(bool has_enable, QMPCapabilityList *enable,
     MonitorQMP *mon;
 
     assert(monitor_is_qmp(cur_mon));
-    mon = container_of(cur_mon, MonitorQMP, common);
+    mon = container_of(cur_mon, MonitorQMP, parent_obj);
 
     if (mon->commands == &qmp_commands) {
         error_set(errp, ERROR_CLASS_COMMAND_NOT_FOUND,
@@ -126,7 +126,7 @@ CommandInfoList *qmp_query_commands(Error **errp)
     MonitorQMP *mon;
 
     assert(monitor_is_qmp(cur_mon));
-    mon = container_of(cur_mon, MonitorQMP, common);
+    mon = container_of(cur_mon, MonitorQMP, parent_obj);
 
     qmp_for_each_command(mon->commands, query_commands_cb, &list);
 
monitor/qmp.c +20 -20
index 687019811f..27934206db 100644
@@ -80,7 +80,7 @@ static void monitor_qmp_caps_reset(MonitorQMP *mon)
 {
     memset(mon->capab_offered, 0, sizeof(mon->capab_offered));
     memset(mon->capab, 0, sizeof(mon->capab));
-    mon->capab_offered[QMP_CAPABILITY_OOB] = mon->common.use_io_thread;
+    mon->capab_offered[QMP_CAPABILITY_OOB] = mon->parent_obj.use_io_thread;
 }
 
 static void qmp_request_free(QMPRequest *req)
@@ -124,7 +124,7 @@ static void monitor_qmp_cleanup_queue_and_resume(MonitorQMP *mon)
          * when we get here while the monitor is suspended.  An
          * unfortunately timed CHR_EVENT_CLOSED can do the trick.
          */
-        monitor_resume(&mon->common);
+        monitor_resume(&mon->parent_obj);
     }
 
 }
@@ -139,7 +139,7 @@ void qmp_send_response(MonitorQMP *mon, const QDict *rsp)
     trace_monitor_qmp_respond(mon, json->str);
 
     g_string_append_c(json, '\n');
-    monitor_puts(&mon->common, json->str);
+    monitor_puts(&mon->parent_obj, json->str);
 
     g_string_free(json, true);
 }
@@ -166,7 +166,7 @@ static void monitor_qmp_dispatch(MonitorQMP *mon, QObject *req)
     QDict *error;
 
     rsp = qmp_dispatch(mon->commands, req, qmp_oob_enabled(mon),
-                       &mon->common);
+                       &mon->parent_obj);
 
     if (mon->commands == &qmp_cap_negotiation_commands) {
         error = qdict_get_qdict(rsp, "error");
@@ -207,7 +207,7 @@ static QMPRequest *monitor_qmp_requests_pop_any_with_lock(void)
             continue;
         }
 
-        qmp_mon = container_of(mon, MonitorQMP, common);
+        qmp_mon = container_of(mon, MonitorQMP, parent_obj);
         qemu_mutex_lock(&qmp_mon->qmp_queue_lock);
         req_obj = g_queue_pop_head(qmp_mon->qmp_requests);
         if (req_obj) {
@@ -302,7 +302,7 @@ void coroutine_fn monitor_qmp_dispatcher_co(void *data)
         oob_enabled = qmp_oob_enabled(mon);
         if (oob_enabled
             && mon->qmp_requests->length == QMP_REQ_QUEUE_LEN_MAX - 1) {
-            monitor_resume(&mon->common);
+            monitor_resume(&mon->parent_obj);
         }
 
         /*
@@ -343,7 +343,7 @@ void coroutine_fn monitor_qmp_dispatcher_co(void *data)
         }
 
         if (!oob_enabled) {
-            monitor_resume(&mon->common);
+            monitor_resume(&mon->parent_obj);
         }
 
         qmp_request_free(req_obj);
@@ -408,7 +408,7 @@ static void handle_qmp_command(void *opaque, QObject *req, Error *err)
          */
         if (!qmp_oob_enabled(mon) ||
             mon->qmp_requests->length == QMP_REQ_QUEUE_LEN_MAX - 1) {
-            monitor_suspend(&mon->common);
+            monitor_suspend(&mon->parent_obj);
         }
 
         /*
@@ -462,7 +462,7 @@ static void monitor_qmp_event(void *opaque, QEMUChrEvent event)
 
     switch (event) {
     case CHR_EVENT_OPENED:
-        WITH_QEMU_LOCK_GUARD(&mon->common.mon_lock) {
+        WITH_QEMU_LOCK_GUARD(&mon->parent_obj.mon_lock) {
             mon->commands = &qmp_cap_negotiation_commands;
             monitor_qmp_caps_reset(mon);
         }
@@ -504,27 +504,27 @@ static void monitor_qmp_setup_handlers_bh(void *opaque)
     MonitorQMP *mon = opaque;
     GMainContext *context;
 
-    assert(mon->common.use_io_thread);
+    assert(mon->parent_obj.use_io_thread);
     context = iothread_get_g_main_context(mon_iothread);
     assert(context);
-    qemu_chr_fe_set_handlers(&mon->common.chr, monitor_can_read,
+    qemu_chr_fe_set_handlers(&mon->parent_obj.chr, monitor_can_read,
                              monitor_qmp_read, monitor_qmp_event,
-                             NULL, &mon->common, context, true);
-    monitor_list_append(&mon->common);
+                             NULL, &mon->parent_obj, context, true);
+    monitor_list_append(&mon->parent_obj);
 }
 
 void monitor_init_qmp(Chardev *chr, bool pretty, Error **errp)
 {
     MonitorQMP *mon = g_new0(MonitorQMP, 1);
 
-    if (!qemu_chr_fe_init(&mon->common.chr, chr, errp)) {
+    if (!qemu_chr_fe_init(&mon->parent_obj.chr, chr, errp)) {
         g_free(mon);
         return;
     }
-    qemu_chr_fe_set_echo(&mon->common.chr, true);
+    qemu_chr_fe_set_echo(&mon->parent_obj.chr, true);
 
     /* Note: we run QMP monitor in I/O thread when @chr supports that */
-    monitor_data_init(&mon->common, true, false,
+    monitor_data_init(&mon->parent_obj, true, false,
                       qemu_chr_has_feature(chr, QEMU_CHAR_FEATURE_GCONTEXT));
 
     mon->pretty = pretty;
@@ -533,7 +533,7 @@ void monitor_init_qmp(Chardev *chr, bool pretty, Error **errp)
     mon->qmp_requests = g_queue_new();
 
     json_message_parser_init(&mon->parser, handle_qmp_command, mon, NULL);
-    if (mon->common.use_io_thread) {
+    if (mon->parent_obj.use_io_thread) {
         /*
          * Make sure the old iowatch is gone.  It's possible when
          * e.g. the chardev is in client mode, with wait=on.
@@ -553,9 +553,9 @@ void monitor_init_qmp(Chardev *chr, bool pretty, Error **errp)
                                 monitor_qmp_setup_handlers_bh, mon);
         /* The bottom half will add @mon to @mon_list */
     } else {
-        qemu_chr_fe_set_handlers(&mon->common.chr, monitor_can_read,
+        qemu_chr_fe_set_handlers(&mon->parent_obj.chr, monitor_can_read,
                                  monitor_qmp_read, monitor_qmp_event,
-                                 NULL, &mon->common, NULL, true);
-        monitor_list_append(&mon->common);
+                                 NULL, &mon->parent_obj, NULL, true);
+        monitor_list_append(&mon->parent_obj);
     }
 }
Signature · 1 line
2.54.0
#23 lore raw

[PULL 17/35] util: use dynamic cast in error vreport

In reply to Markus Armbruster

From: Daniel P. Berrangé <[email protected]>

This eliminates a use of monitor_is_qmp() from the error reporting path.

Message-ID: <[email protected]>

---
 util/error-report.c | 13 ++++++-------
 1 file changed, 6 insertions(+), 7 deletions(-)
util/error-report.c +6 -7
index f832ad9b6b..f333af9249 100644
@@ -231,16 +231,15 @@ char *real_time_iso8601(void)
 G_GNUC_PRINTF(2, 0)
 static void vreport(report_type type, const char *fmt, va_list ap)
 {
-    Monitor *cur = monitor_cur();
-    gchar *timestr;
-
     /*
      * When current monitor is QMP, messages must go to stderr
-     * and have prefixes added
+     * and have prefixes added, so we cast to HMP, leaving 'cur'
+     * as NULL in QMP case
      */
-    if (monitor_cur_is_qmp()) {
-        cur = NULL;
-    }
+    Monitor *cur = MONITOR(
+        object_dynamic_cast(OBJECT(monitor_cur()), TYPE_MONITOR_HMP));
+    gchar *timestr;
+
     if (!cur) {
         qemu_flockfile(stderr);
     }
Signature · 1 line
2.54.0
#24 lore raw

[PULL 20/35] monitor: use dynamic cast in monitor_is_hmp_non_interactive

In reply to Markus Armbruster

From: Daniel P. Berrangé <[email protected]>

Rather than checking !monitor_is_qmp(), use a dynamic cast to check for HMP.

Message-ID: <[email protected]>

---
 monitor/monitor.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
monitor/monitor.c +1 -1
index a818659392..6fdd0255f4 100644
@@ -170,7 +170,7 @@ static inline bool monitor_uses_readline(const MonitorHMP *mon)
 
 static inline bool monitor_is_hmp_non_interactive(const Monitor *mon)
 {
-    if (monitor_is_qmp(mon)) {
+    if (!object_dynamic_cast(OBJECT(mon), TYPE_MONITOR_HMP)) {
         return false;
     }
 
Signature · 1 line
2.54.0
#25 lore raw

[PULL 29/35] tests/functional: add e2e test for dynamic QMP monitor hotplug

In reply to Markus Armbruster

From: Christian Brauner <[email protected]>

Add functional tests that exercise dynamic monitor hotplug with real socket connections:

- Hotplug cycle: chardev-add a unix socket, object-add, connect to the socket, receive the QMP greeting, negotiate capabilities, send query-version, disconnect, remove the monitor and chardev, then repeat the entire cycle a second time to verify cleanup and reuse.

- Self-removal: a dynamically-added monitor sends object-del targeting itself, verifying that the request is rejected

- Large response: send query-qmp-schema on a dynamic monitor to exercise the output buffer flush path with a large response payload.

- Events after negotiation: trigger STOP/RESUME events via the main monitor and verify they are delivered on the dynamic monitor.

This complements the qtest unit tests by verifying that a real QMP client can connect to a dynamically-added monitor and exchange messages.

[DB: modified to use object-add/object-del; adjust self-removal test
to validate rejection of request]

Message-ID: <[email protected]>

---
 MAINTAINERS                                   |   1 +
 tests/functional/generic/meson.build          |   1 +
 .../generic/test_monitor_hotplug.py           | 168 ++++++++++++++++++
 3 files changed, 170 insertions(+)
 create mode 100755 tests/functional/generic/test_monitor_hotplug.py
MAINTAINERS +1 -0
index 1e239f2116..10352b2633 100644
@@ -3672,6 +3672,7 @@ F: docs/interop/*qmp-*
 F: scripts/qmp/
 F: tests/qtest/qmp-test.c
 F: tests/qtest/qmp-cmd-test.c
+F: tests/functional/generic/test_monitor_hotplug.py
 T: git https://repo.or.cz/qemu/armbru.git qapi-next
 
 qtest
tests/functional/generic/meson.build +1 -0
index 09763c5d22..c94105c62e 100644
@@ -4,6 +4,7 @@ tests_generic_system = [
   'empty_cpu_model',
   'info_usernet',
   'linters',
+  'monitor_hotplug',
   'version',
   'vnc',
 ]
tests/functional/generic/test_monitor_hotplug.py new file +168 -0

168 lines not on this page · raw message

Signature · 1 line
2.54.0
#26 lore raw

[PULL 22/35] monitor: eliminate monitor_is_hmp_non_interactive method

In reply to Markus Armbruster

From: Daniel P. Berrangé <[email protected]>

The monitor_is_hmp_non_interactive method is used by monitor_suspend and monitor_resume, to make them a no-op if the HMP does not use readline.

There are only a handful of callers of suspend/resume and they can be made to skip the call when readline is not present.

Message-ID: <[email protected]>

---
 include/monitor/monitor.h      |  2 +-
 migration/migration-hmp-cmds.c |  5 ++++-
 monitor/hmp-cmds.c             |  5 ++++-
 monitor/hmp.c                  | 11 ++++++++---
 monitor/monitor.c              | 30 +-----------------------------
 5 files changed, 18 insertions(+), 35 deletions(-)
include/monitor/monitor.h +1 -1
index e802e8dfb2..890497b0d2 100644
@@ -37,7 +37,7 @@ int monitor_new(MonitorOptions *opts, bool allow_hmp, Error **errp);
 int monitor_new_opts(QemuOpts *opts, Error **errp);
 void monitor_cleanup(void);
 
-int monitor_suspend(Monitor *mon);
+void monitor_suspend(Monitor *mon);
 void monitor_resume(Monitor *mon);
 
 int monitor_get_fd(Monitor *mon, const char *fdname, Error **errp);
migration/migration-hmp-cmds.c +4 -1
index 8b385f560e..502ca704da 100644
@@ -19,6 +19,7 @@
 #include "monitor/hmp.h"
 #include "monitor/hmp-completion.h"
 #include "monitor/monitor.h"
+#include "monitor/monitor-internal.h"
 #include "qapi/error.h"
 #include "qapi/qapi-commands-migration.h"
 #include "qapi/qapi-visit-migration.h"
@@ -853,12 +854,14 @@ void hmp_migrate(Monitor *mon, const QDict *qdict)
 
     if (!detach) {
         HMPMigrationStatus *status;
+        MonitorHMP *hmp = MONITOR_HMP(mon);
 
-        if (monitor_suspend(mon) < 0) {
+        if (!hmp->use_readline) {
             monitor_printf(mon, "terminal does not allow synchronous "
                            "migration, continuing detached\n");
             return;
         }
+        monitor_suspend(mon);
 
         status = g_malloc0(sizeof(*status));
         status->mon = mon;
monitor/hmp-cmds.c +4 -1
index e139caeba9..e9fb8d827a 100644
@@ -129,7 +129,10 @@ void hmp_info_version(Monitor *mon, const QDict *qdict)
 
 void hmp_quit(Monitor *mon, const QDict *qdict)
 {
-    monitor_suspend(mon);
+    MonitorHMP *hmp = MONITOR_HMP(mon);
+    if (hmp->use_readline) {
+        monitor_suspend(mon);
+    }
     qmp_quit(NULL);
 }
 
monitor/hmp.c +8 -3
index 4636165d0b..a51de8e467 100644
@@ -1528,13 +1528,16 @@ static void monitor_read(void *opaque, const uint8_t *buf, int size)
 static void monitor_event(void *opaque, QEMUChrEvent event)
 {
     Monitor *mon = opaque;
+    MonitorHMP *hmp = MONITOR_HMP(mon);
 
     switch (event) {
     case CHR_EVENT_MUX_IN:
         qemu_mutex_lock(&mon->mon_lock);
         if (mon->mux_out) {
             mon->mux_out = 0;
-            monitor_resume(mon);
+            if (hmp->use_readline) {
+                monitor_resume(mon);
+            }
         }
         qemu_mutex_unlock(&mon->mon_lock);
         break;
@@ -1547,7 +1550,9 @@ static void monitor_event(void *opaque, QEMUChrEvent event)
             } else {
                 monitor_flush_locked(mon);
             }
-            monitor_suspend(mon);
+            if (hmp->use_readline) {
+                monitor_suspend(mon);
+            }
             mon->mux_out = 1;
         }
         qemu_mutex_unlock(&mon->mon_lock);
@@ -1558,7 +1563,7 @@ static void monitor_event(void *opaque, QEMUChrEvent event)
                        "information\n", QEMU_VERSION);
         qemu_mutex_lock(&mon->mon_lock);
         mon->reset_seen = 1;
-        if (!mon->mux_out) {
+        if (!mon->mux_out && hmp->use_readline) {
             /* Suspend-resume forces the prompt to be printed.  */
             monitor_suspend(mon);
             monitor_resume(mon);
monitor/monitor.c +1 -29
index 9b62716033..f1b189c1c2 100644
@@ -157,25 +157,6 @@ bool monitor_requires_iothread(const Monitor *mon)
     return cls->requires_iothread && cls->requires_iothread(mon);
 }
 
-/**
- * Is @mon is using readline?
- * Note: not all HMP monitors use readline, e.g., gdbserver has a
- * non-interactive HMP monitor, so readline is not used there.
- */
-static inline bool monitor_uses_readline(const MonitorHMP *mon)
-{
-    return mon->use_readline;
-}
-
-static inline bool monitor_is_hmp_non_interactive(const Monitor *mon)
-{
-    if (!object_dynamic_cast(OBJECT(mon), TYPE_MONITOR_HMP)) {
-        return false;
-    }
-
-    return !monitor_uses_readline(container_of(mon, MonitorHMP, parent_obj));
-}
-
 static gboolean monitor_unblocked(void *do_not_use, GIOCondition cond,
                                   void *opaque)
 {
@@ -550,12 +531,8 @@ static gboolean qapi_event_throttle_equal(const void *a, const void *b)
     return TRUE;
 }
 
-int monitor_suspend(Monitor *mon)
+void monitor_suspend(Monitor *mon)
 {
-    if (monitor_is_hmp_non_interactive(mon)) {
-        return -ENOTTY;
-    }
-
     qatomic_inc(&mon->suspend_cnt);
 
     if (monitor_requires_iothread(mon)) {
@@ -567,7 +544,6 @@ int monitor_suspend(Monitor *mon)
     }
 
     trace_monitor_suspend(mon, 1);
-    return 0;
 }
 
 static void monitor_accept_input(void *opaque)
@@ -584,10 +560,6 @@ static void monitor_accept_input(void *opaque)
 
 void monitor_resume(Monitor *mon)
 {
-    if (monitor_is_hmp_non_interactive(mon)) {
-        return;
-    }
-
     if (qatomic_dec_fetch(&mon->suspend_cnt) == 0) {
         AioContext *ctx;
 
Signature · 1 line
2.54.0
#27 lore raw

[PULL 27/35] monitor: implement support for deleting QMP objects

In reply to Markus Armbruster

From: Christian Brauner <[email protected]>

The removal sequence is:

1. Remove from mon_list under monitor_lock. This must happen before disconnecting chardev handlers to prevent event broadcast from calling monitor_flush_locked() after the gcontext reset, which would create an out_watch on the wrong GMainContext (see monitor_cancel_out_watch()).
2. Cancel any pending out_watch while gcontext still points to the correct context.
3. Disconnect chardev handlers, passing context=NULL and close the connection.
4. Drain pending requests from any in-flight monitor_qmp_read().
5. Destroy the monitor object

[DB: extracted from a larger commit and refactored to apply
to the new monitor class structure. Remove 'self delete' feature which requires complex special-case code]

Message-ID: <[email protected]>

---
 monitor/monitor-internal.h |  2 ++
 monitor/monitor.c          | 22 ++++++++++++++++
 monitor/qmp.c              | 54 ++++++++++++++++++++++++++++++++++++--
 3 files changed, 76 insertions(+), 2 deletions(-)
monitor/monitor-internal.h +2 -0
index a82e1aacb6..5522e05464 100644
@@ -178,6 +178,7 @@ struct MonitorQMP {
     Monitor parent_obj;
     JSONMessageParser parser;
     bool pretty;
+    bool setup_pending; /* iothread BH has not yet set up chardev handlers */
     /*
      * When a client connects, we're in capabilities negotiation mode.
      * @commands is &qmp_cap_negotiation_commands then.  When command
@@ -206,6 +207,7 @@ extern MonitorList mon_list;
 
 bool monitor_requires_iothread(const Monitor *mon);
 int monitor_can_read(void *opaque);
+void monitor_cancel_out_watch(Monitor *mon);
 void monitor_list_append(Monitor *mon);
 void monitor_fdsets_cleanup(void);
 int monitor_set_cpu(Monitor *mon, int cpu_index);
monitor/monitor.c +22 -0
index 4a45c15a36..ed195fd97b 100644
@@ -179,6 +179,28 @@ static gboolean monitor_unblocked(void *do_not_use, GIOCondition cond,
     return G_SOURCE_REMOVE;
 }
 
+/* Cancel a pending out_watch GSource.  Caller must hold mon_lock. */
+void monitor_cancel_out_watch(Monitor *mon)
+{
+    if (mon->out_watch) {
+        GMainContext *ctx = NULL;
+        GSource *src;
+
+        if (monitor_requires_iothread(mon)) {
+            ctx = iothread_get_g_main_context(mon_iothread);
+        }
+        src = g_main_context_find_source_by_id(ctx, mon->out_watch);
+        if (!src && ctx) {
+            /* Handler disconnect may have reset gcontext to NULL. */
+            src = g_main_context_find_source_by_id(NULL, mon->out_watch);
+        }
+        if (src) {
+            g_source_destroy(src);
+        }
+        mon->out_watch = 0;
+    }
+}
+
 /* Caller must hold mon->mon_lock */
 void monitor_flush_locked(Monitor *mon)
 {
monitor/qmp.c +52 -2

86 lines not on this page · raw message

Signature · 1 line
2.54.0
#28 lore raw

[PULL 04/35] monitor: rename monitor_init* to monitor_new*

In reply to Markus Armbruster

From: Daniel P. Berrangé <[email protected]>

The current "monitor_init" functions will clash with the methods of the same name that are required by QOM. To ease the transition to QOM, rename them out of the way.

Message-ID: <[email protected]>

---
 include/monitor/monitor.h            |  8 ++++----
 chardev/char.c                       |  2 +-
 gdbstub/system.c                     |  2 +-
 monitor/hmp.c                        |  2 +-
 monitor/monitor.c                    | 10 +++++-----
 monitor/qmp.c                        |  2 +-
 storage-daemon/qemu-storage-daemon.c |  2 +-
 stubs/monitor-internal.c             |  2 +-
 system/vl.c                          |  2 +-
 9 files changed, 16 insertions(+), 16 deletions(-)
include/monitor/monitor.h +4 -4
index 55649a8664..b9642b58ba 100644
@@ -19,10 +19,10 @@ bool monitor_cur_is_qmp(void);
 
 void monitor_init_globals(void);
 void monitor_init_globals_core(void);
-void monitor_init_qmp(Chardev *chr, bool pretty, Error **errp);
-void monitor_init_hmp(Chardev *chr, bool use_readline, Error **errp);
-int monitor_init(MonitorOptions *opts, bool allow_hmp, Error **errp);
-int monitor_init_opts(QemuOpts *opts, Error **errp);
+void monitor_new_qmp(Chardev *chr, bool pretty, Error **errp);
+void monitor_new_hmp(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);
 
 int monitor_suspend(Monitor *mon);
chardev/char.c +1 -1
index ca8b37ed8d..813c04d953 100644
@@ -805,7 +805,7 @@ static Chardev *qemu_chr_new_from_name(const char *label, const char *filename,
 
     if (qemu_opt_get_bool(opts, "mux", 0)) {
         assert(permit_mux_mon);
-        monitor_init_hmp(chr, true, &err);
+        monitor_new_hmp(chr, true, &err);
         if (err) {
             error_report_err(err);
             object_unparent(OBJECT(chr));
gdbstub/system.c +1 -1
index 3098fd5574..03e088b17d 100644
@@ -390,7 +390,7 @@ bool gdbserver_start(const char *device, Error **errp)
         /* Initialize a monitor terminal for gdb */
         mon_chr = qemu_chardev_new(NULL, TYPE_CHARDEV_GDB,
                                    NULL, NULL, &error_abort);
-        monitor_init_hmp(mon_chr, false, &error_abort);
+        monitor_new_hmp(mon_chr, false, &error_abort);
     } else {
         qemu_chr_fe_deinit(&gdbserver_system_state.chr, true);
         mon_chr = gdbserver_system_state.mon_chr;
monitor/hmp.c +1 -1
index 3dde52ddbe..4e4468424a 100644
@@ -1524,7 +1524,7 @@ static void monitor_readline_flush(void *opaque)
     monitor_flush(&mon->parent_obj);
 }
 
-void monitor_init_hmp(Chardev *chr, bool use_readline, Error **errp)
+void monitor_new_hmp(Chardev *chr, bool use_readline, Error **errp)
 {
     MonitorHMP *mon = g_new0(MonitorHMP, 1);
 
monitor/monitor.c +5 -5
index 0b7b464ebe..a87597e606 100644
@@ -715,7 +715,7 @@ void monitor_init_globals(void)
     aio_co_schedule(iohandler_get_aio_context(), qmp_dispatcher_co);
 }
 
-int monitor_init(MonitorOptions *opts, bool allow_hmp, Error **errp)
+int monitor_new(MonitorOptions *opts, bool allow_hmp, Error **errp)
 {
     ERRP_GUARD();
     Chardev *chr;
@@ -732,7 +732,7 @@ int monitor_init(MonitorOptions *opts, bool allow_hmp, Error **errp)
 
     switch (opts->mode) {
     case MONITOR_MODE_CONTROL:
-        monitor_init_qmp(chr, opts->pretty, errp);
+        monitor_new_qmp(chr, opts->pretty, errp);
         break;
     case MONITOR_MODE_READLINE:
         if (!allow_hmp) {
@@ -743,7 +743,7 @@ int monitor_init(MonitorOptions *opts, bool allow_hmp, Error **errp)
             error_setg(errp, "'pretty' is not compatible with HMP monitors");
             return -1;
         }
-        monitor_init_hmp(chr, true, errp);
+        monitor_new_hmp(chr, true, errp);
         break;
     default:
         g_assert_not_reached();
@@ -752,7 +752,7 @@ int monitor_init(MonitorOptions *opts, bool allow_hmp, Error **errp)
     return *errp ? -1 : 0;
 }
 
-int monitor_init_opts(QemuOpts *opts, Error **errp)
+int monitor_new_opts(QemuOpts *opts, Error **errp)
 {
     Visitor *v;
     MonitorOptions *options;
@@ -765,7 +765,7 @@ int monitor_init_opts(QemuOpts *opts, Error **errp)
         return -1;
     }
 
-    ret = monitor_init(options, true, errp);
+    ret = monitor_new(options, true, errp);
     qapi_free_MonitorOptions(options);
     return ret;
 }
monitor/qmp.c +1 -1
index 27934206db..cb28a95efd 100644
@@ -513,7 +513,7 @@ static void monitor_qmp_setup_handlers_bh(void *opaque)
     monitor_list_append(&mon->parent_obj);
 }
 
-void monitor_init_qmp(Chardev *chr, bool pretty, Error **errp)
+void monitor_new_qmp(Chardev *chr, bool pretty, Error **errp)
 {
     MonitorQMP *mon = g_new0(MonitorQMP, 1);
 
storage-daemon/qemu-storage-daemon.c +1 -1
index eb72561358..50dbfbd97a 100644
@@ -330,7 +330,7 @@ static void process_options(int argc, char *argv[], bool pre_init_pass)
                 visit_free(v);
 
                 /* TODO Catch duplicate monitor IDs */
-                monitor_init(monitor, false, &error_fatal);
+                monitor_new(monitor, false, &error_fatal);
                 qapi_free_MonitorOptions(monitor);
                 break;
             }
stubs/monitor-internal.c +1 -1
index 4fece49d53..23d58da184 100644
@@ -8,6 +8,6 @@ int monitor_get_fd(Monitor *mon, const char *name, Error **errp)
     return -1;
 }
 
-void monitor_init_hmp(Chardev *chr, bool use_readline, Error **errp)
+void monitor_new_hmp(Chardev *chr, bool use_readline, Error **errp)
 {
 }
system/vl.c +1 -1
index 1d14e2e207..6643242729 100644
@@ -1247,7 +1247,7 @@ static int fsdev_init_func(void *opaque, QemuOpts *opts, Error **errp)
 
 static int mon_init_func(void *opaque, QemuOpts *opts, Error **errp)
 {
-    return monitor_init_opts(opts, errp);
+    return monitor_new_opts(opts, errp);
 }
 
 static void monitor_parse(const char *str, const char *mode, bool pretty)
Signature · 1 line
2.54.0
#29 lore raw

[PULL 33/35] tests: switch from -mon to -object monitor-qmp

In reply to Markus Armbruster

From: Daniel P. Berrangé <[email protected]>

Use the new preferred low level option for configuring the QMP service in libqtest and the python Machine class used by tests. This will avoid triggering deprecation warnings after the subsequent commit.

Message-ID: <[email protected]>

---
 tests/qtest/libqtest.c         | 2 +-
 python/qemu/machine/machine.py | 4 ++--
 2 files changed, 3 insertions(+), 3 deletions(-)
tests/qtest/libqtest.c +1 -1
index 4e22c66b75..c33c799c92 100644
@@ -460,7 +460,7 @@ gchar *qtest_qemu_args(const char *extra_args)
                       "-qtest unix:%s "
                       "-qtest-log %s "
                       "-chardev socket,path=%s,id=char0 "
-                      "-mon chardev=char0,mode=control "
+                      "-object monitor-qmp,id=qmp0,chardev=char0 "
                       "-display none "
                       "-audio none "
                       "%s "
python/qemu/machine/machine.py +2 -2
index 3670c8cd39..bfb59d4c0b 100644
@@ -304,8 +304,8 @@ def _harness_args(self) -> List[str]:
                 )
             else:
                 moncdev = f"socket,id=mon,path={self._monitor_address}"
-            args.extend(['-chardev', moncdev, '-mon',
-                         'chardev=mon,mode=control'])
+            args.extend(['-chardev', moncdev, '-object',
+                         'monitor-qmp,id=qmp,chardev=mon'])
         return args
 
     def _console_args(self, interactive: bool = False) -> List[str]:
Signature · 1 line
2.54.0
#30 lore raw

[PULL 35/35] docs: mark '-mon' as deprecated in favour of -object

In reply to Markus Armbruster

From: Daniel P. Berrangé <[email protected]>

The high level -qmp and -monitor options can remain as convenience wrappers, but the low level -mon is completed obsoleted by the new -object support with 'monitor-qmp' and 'monitor-hmp' types.

Message-ID: <[email protected]>

[Editing accident fixed in qemu-options.hx]
---
 docs/about/deprecated.rst               | 10 ++++++++++
 docs/devel/writing-monitor-commands.rst |  4 ++--
 docs/system/arm/xenpvh.rst              |  4 ++--
 docs/system/i386/xen.rst                |  3 ++-
 docs/system/i386/xenpvh.rst             |  4 ++--
 system/vl.c                             |  2 ++
 qemu-options.hx                         | 15 +++++++--------
 7 files changed, 27 insertions(+), 15 deletions(-)
docs/about/deprecated.rst +10 -0
index ef1d7b9ea8..0c656a968f 100644
@@ -61,6 +61,16 @@ The ``debug-threads`` option of the ``-name`` argument is now
 ignored. Thread naming is unconditionally enabled for all platforms
 where it is supported.
 
+``-mon`` option (since 11.1)
+''''''''''''''''''''''''''''
+
+The ``-mon`` option was the generic mechanism for creating monitor
+objects if the convenience ``-qmp`` or ``-monitor`` options were not
+flexible enough. The monitor objects have been converted to QOM, so
+``-mon mode=readline`` is replaced by ``-object monitor-hmp`` and
+``-mon mode=control`` is replaced by ``-object monitor-qmp``. The
+short convenience options are not deprecated, only ``-mon``.
+
 QEMU Machine Protocol (QMP) commands
 ------------------------------------
 
docs/devel/writing-monitor-commands.rst +2 -2
index 930da5cd06..7ae7efe327 100644
@@ -52,8 +52,8 @@ shown here.
 First, QEMU should be started like this::
 
  # qemu-system-TARGET [...] \
-     -chardev socket,id=qmp,port=4444,host=localhost,server=on \
-     -mon chardev=qmp,mode=control,pretty=on
+     -chardev socket,id=chrqmp0,port=4444,host=localhost,server=on \
+     -object monitor-qmp,chardev=chrqmp0,pretty=on,id=qmp0
 
 Then, in a different terminal::
 
docs/system/arm/xenpvh.rst +2 -2
index 430ac2c02e..511af63e3d 100644
@@ -27,9 +27,9 @@ Sample QEMU xenpvh commands for running and connecting with Xen:
 
     qemu-system-aarch64 -xen-domid 1 \
       -chardev socket,id=libxl-cmd,path=qmp-libxl-1,server=on,wait=off \
-      -mon chardev=libxl-cmd,mode=control \
+      -object monitor-qmp,id=qmp0,chardev=libxl-cmd \
       -chardev socket,id=libxenstat-cmd,path=qmp-libxenstat-1,server=on,wait=off \
-      -mon chardev=libxenstat-cmd,mode=control \
+      -object monitor-qmp,id=qmp1,chardev=libxenstat-cmd \
       -xen-attach -name guest0 -vnc none -display none -nographic \
       -machine xenpvh -m 1301 \
       -chardev socket,id=chrtpm,path=tmp/vtpm2/swtpm-sock \
docs/system/i386/xen.rst +2 -1
index 46db5f34c1..6ff5cdb1e4 100644
@@ -79,7 +79,8 @@ of type ``xen-console`` to connect to it. For the Xen console equivalent of
 the handy ``-serial mon:stdio`` option, for example:
 
 .. parsed-literal::
-   -chardev stdio,mux=on,id=char0,signal=off -mon char0 \\
+   -chardev stdio,mux=on,id=char0,signal=off \\
+   -object monitor-hmp,chardev=char0,id=hmp0 \\
    -device xen-console,chardev=char0
 
 The Xen network device is ``xen-net-device``, which becomes the default NIC
docs/system/i386/xenpvh.rst +2 -2
index 354250f073..904778e3f5 100644
@@ -33,9 +33,9 @@ case you need to construct one manually:
 
     qemu-system-i386 -xen-domid 3 -no-shutdown        \
       -chardev socket,id=libxl-cmd,path=/var/run/xen/qmp-libxl-3,server=on,wait=off \
-      -mon chardev=libxl-cmd,mode=control             \
+      -object monitor-qmp,id=qmp0,chardev=libxl-cmd   \
       -chardev socket,id=libxenstat-cmd,path=/var/run/xen/qmp-libxenstat-3,server=on,wait=off \
-      -mon chardev=libxenstat-cmd,mode=control        \
+      -object monitor-qmp,id=qmp1,chardev=libxenstat-cmd \
       -nodefaults                                     \
       -no-user-config                                 \
       -xen-attach -name g0                            \
system/vl.c +2 -0
index 63bdd06dfa..061cbdf860 100644
@@ -3239,6 +3239,8 @@ void qemu_init(int argc, char **argv)
                 default_monitor = 0;
                 break;
             case QEMU_OPTION_mon:
+                warn_report_once("'-mon' is deprecated, use '-object' with "
+                                 "'monitor-hmp' or 'monitor-qmp' types instead");
                 if (!qemu_opts_parse_noisily(qemu_find_opts("mon"), optarg,
                                              true)) {
                     exit(1);
qemu-options.hx +7 -8
index fe76c18c81..308864a185 100644
@@ -4154,7 +4154,7 @@ The general form of a character device option is:
     ::
 
         -chardev stdio,mux=on,id=char0 \
-        -mon chardev=char0,mode=readline \
+        -object monitor-hmp,id=hmp0,chardev=char0 \
         -serial chardev:char0 \
         -serial chardev:char0
 
@@ -4166,7 +4166,7 @@ The general form of a character device option is:
     ::
 
         -chardev stdio,mux=on,id=char0 \
-        -mon chardev=char0,mode=readline \
+        -object monitor-hmp,id=hmp0,chardev=char0 \
         -parallel chardev:char0 \
         -chardev tcp,...,mux=on,id=char1 \
         -serial chardev:char1 \
@@ -5004,12 +5004,12 @@ SRST
 
     enables the QMP monitor on localhost port 4444 with pretty-printing.
 
-    The use of ``-mon mode=readline`` is syntactic sugar
+    The use of ``-mon mode=readline`` is deprecated syntactic sugar
     for the new ``-object monitor-hmp`` option, each use of which
     creates an object with the ID ``compat_monitorNNN`` where ``NNN`` is
     a counter starting from 0.
 
-    The use of ``-mon mode=control`` is syntactic sugar
+    The use of ``-mon mode=control`` is deprecated syntactic sugar
     for the new ``-object monitor-qmp`` option, each use of which
     creates an object with the ID ``compat_monitorNNN`` where ``NNN`` is
     a counter starting from 0.
@@ -5771,8 +5771,7 @@ SRST
         to dynamically delete the monitor at runtime. Note
         that monitors created using the historical syntax
         will be allocated IDs following the pattern ``compat_monmitorNNN``.
-        Mixing ``-object`` with ``-monitor`` and ``-mon`` syntax is
-        discouraged.
+        Mixing ``-object`` with ``-monitor`` syntax is discouraged.
 
         The ``readline`` parameter, which defaults to ``on``,
         controls whether the monitor provides line editing.
@@ -5785,8 +5784,8 @@ SRST
         to dynamically delete the monitor at runtime. Note
         that monitors created using the historical syntax
         will be allocated IDs following the pattern ``compat_monitorNNN``.
-        Mixing ``-object`` with ``-qmp``, ``-qmp-pretty`` and
-        ``-mon`` syntax is discouraged.
+        Mixing ``-object`` with ``-qmp`` and ``-qmp-pretty``
+        syntax is discouraged.
 
         The ``pretty`` parameter, which defaults to ``off``,
         controls whether the monitor responses are pretty
Signature · 1 line
2.54.0
#31 lore raw

Re: [PULL 35/35] docs: mark '-mon' as deprecated in favour of -object

Quoted 9 lines · Markus Armbruster

From: Daniel P. Berrangé <[email protected]>

The high level -qmp and -monitor options can remain as convenience wrappers, but the low level -mon is completed obsoleted by the new -object support with 'monitor-qmp' and 'monitor-hmp' types.

system/vl.c void qemu_init(int argc, char **argv) · line 3243

Quoted 5 lines
system/vl.c +2 -0
@@ -3239,6 +3239,8 @@ void qemu_init(int argc, char **argv)
                 default_monitor = 0;
                 break;
             case QEMU_OPTION_mon:
+                warn_report_once("'-mon' is deprecated, use '-object' with "
+                                 "'monitor-hmp' or 'monitor-qmp' types instead");

Can we be more precise in deprecation messages of this kind, please? This warning is not enough for the user to be able to figure out how to change their existing command line.

I had to look into deprecated.rst, check the git history to see which commit added the deprecation, then find out how this commit was adjusting the examples in the tree.

Notably, "-object monitor-hmp" appears to require an "id=" despite nothing actually caring what that ID is, and the warning message doesn't say how to determine whether your existing -mon option should be changed to monitor-hmp or monitor-qmp. The deprecated.rst docs do say that part, but don't mention the ID bit.

thanks
-- PMM

#32 lore raw

Re: [PULL 35/35] docs: mark '-mon' as deprecated in favour of -object

Quoted 20 lines · Peter Maydell
Quoted 9 lines · Markus Armbruster

From: Daniel P. Berrangé <[email protected]>

The high level -qmp and -monitor options can remain as convenience wrappers, but the low level -mon is completed obsoleted by the new -object support with 'monitor-qmp' and 'monitor-hmp' types.

system/vl.c void qemu_init(int argc, char **argv) · line 3243

Quoted 5 lines
system/vl.c +2 -0
@@ -3239,6 +3239,8 @@ void qemu_init(int argc, char **argv)
                 default_monitor = 0;
                 break;
             case QEMU_OPTION_mon:
+                warn_report_once("'-mon' is deprecated, use '-object' with "
+                                 "'monitor-hmp' or 'monitor-qmp' types instead");

Can we be more precise in deprecation messages of this kind, please? This warning is not enough for the user to be able to figure out how to change their existing command line.

Quoted 6 lines

I had to look into deprecated.rst, check the git history to see which commit added the deprecation, then find out how this commit was adjusting the examples in the tree.

Notably, "-object monitor-hmp" appears to require an "id=" despite nothing actually caring what that ID is,

Yes, -object requires @id regardless of object type. It calls object_new_with_props_from_qdict() via user_creatable_add_qapi(). Together, they create the object at /objects/ID.

Quoted 4 lines

and the warning message
doesn't say how to determine whether your existing -mon option should be changed to monitor-hmp or monitor-qmp. The deprecated.rst docs do say that part, but don't mention the ID bit.

Fair points.

Is this just "do better in the future", or are you also asking for a patch to improve this warning?

#33 lore raw

Re: [PULL 35/35] docs: mark '-mon' as deprecated in favour of -object

Quoted 9 lines · Markus Armbruster
Quoted 8 lines · Peter Maydell

Can we be more precise in deprecation messages of this kind, please? This warning is not enough for the user to be able to figure out how to change their existing command line.

I had to look into deprecated.rst, check the git history to see which commit added the deprecation, then find out how this commit was adjusting the examples in the tree.

Quoted 6 lines
Quoted 2 lines

Notably, "-object monitor-hmp" appears to require an "id=" despite nothing actually caring what that ID is,

Yes, -object requires @id regardless of object type. It calls object_new_with_props_from_qdict() via user_creatable_add_qapi(). Together, they create the object at /objects/ID.

Yes, but usually you need the ID because it's going to plug into some other option somewhere else; other options like -drive can take an id=, but don't insist on it if you don't need it, and some options like chardev are only useful if you connect them to something else by using the ID elsewhere in the command line, so whether they require id= or not never comes up. So the idea of an option requiring an ID even though it is never referenced anywhere else may well be new to the user.

Mostly I mention it because otherwise I think the typical user is going to do what I did, i.e. replace "-mon" with "-object monitor-hmp" and then immediately get a different error from QEMU. The warning being more precise could save them a step.

Quoted 9 lines
Quoted 4 lines

and the warning message
doesn't say how to determine whether your existing -mon option should be changed to monitor-hmp or monitor-qmp. The deprecated.rst docs do say that part, but don't mention the ID bit.

Fair points.

Is this just "do better in the future", or are you also asking for a patch to improve this warning?

Both, preferably :-)

There's an argument that the deprecation warning could look at the option the user actually provided and emit the exact right new option to use instead. But I don't think that's something we've ever done before for deprecations.

-- PMM

#34 lore raw

Re: [PULL 35/35] docs: mark '-mon' as deprecated in favour of -object

Quoted 17 lines · Peter Maydell
Quoted 9 lines · Markus Armbruster
Quoted 8 lines · Peter Maydell

Can we be more precise in deprecation messages of this kind, please? This warning is not enough for the user to be able to figure out how to change their existing command line.

I had to look into deprecated.rst, check the git history to see which commit added the deprecation, then find out how this commit was adjusting the examples in the tree.

Quoted 6 lines
Quoted 2 lines

Notably, "-object monitor-hmp" appears to require an "id=" despite nothing actually caring what that ID is,

Yes, -object requires @id regardless of object type. It calls object_new_with_props_from_qdict() via user_creatable_add_qapi(). Together, they create the object at /objects/ID.

Quoted 8 lines

Yes, but usually you need the ID because it's going to plug into some other option somewhere else; other options like -drive can take an id=, but don't insist on it if you don't need it, and some options like chardev are only useful if you connect them to something else by using the ID elsewhere in the command line, so whether they require id= or not never comes up. So the idea of an option requiring an ID even though it is never referenced anywhere else may well be new to the user.

FYI, the ID for the monitor can be used with object-del QMP/HMP commands.

Quoted 4 lines

Mostly I mention it because otherwise I think the typical user is going to do what I did, i.e. replace "-mon" with "-object monitor-hmp" and then immediately get a different error from QEMU. The warning being more precise could save them a step.

I was thinking that the user would do 'man qemu' where we have docs for "-object", for each object type including "monitor-hmp/qmp", which are shown taking an ID parameter.

Quoted 11 lines
Quoted 10 lines
Quoted 5 lines

and the warning message
doesn't say how to determine whether your existing -mon option should be changed to monitor-hmp or monitor-qmp. The deprecated.rst docs do say that part, but don't mention the ID bit.

Fair points.

Is this just "do better in the future", or are you also asking for a patch to improve this warning?

Quoted 6 lines

Both, preferably :-)

There's an argument that the deprecation warning could look at the option the user actually provided and emit the exact right new option to use instead. But I don't think that's something we've ever done before for deprecations.

Essentially we have three distinct places with info - the deprecation message at runtime, the deprecated.rst docs, and the qemu.1 manual page. It is a trade off between how much effort we want to put into each area.

For humans I anticipated they'd be mostly using -monitor / -qmp convenience options, with -mon mostly used by machines which are already familiar with -object usage already.

With regards,
Daniel

Signature · 3 lines
|: https://berrange.com       ~~        https://hachyderm.io/@berrange :|
|: https://libvirt.org          ~~          https://entangle-photo.org :|
|: https://pixelfed.art/berrange   ~~    https://fstop138.berrange.com :|
#35 lore raw

Re: [PULL 35/35] docs: mark '-mon' as deprecated in favour of -object

Quoted 9 lines · Daniel P. Berrangé
Quoted 4 lines · Peter Maydell

Mostly I mention it because otherwise I think the typical user is going to do what I did, i.e. replace "-mon" with "-object monitor-hmp" and then immediately get a different error from QEMU. The warning being more precise could save them a step.

I was thinking that the user would do 'man qemu' where we have docs for "-object", for each object type including "monitor-hmp/qmp", which are shown taking an ID parameter.

But they only have to look at the docs because the warning message we just printed doesn't give them enough information.

FWIW, I did try the docs: putting "monitor-hmp" into the online HTML search produces as the top hit the "Deprecated features" subsection, which also doesn't give enough information (and doesn't hyperlink to anywhere else that gives more information[*]), and then a lot of other irrelevant hits because the search seems to be word based so it shows you everything with either "monitor" or "HMP".
At this point I gave up and started looking around in the git history.

[*] partly this is because hyperlinks into the qemu-options.hx docs are awkward. We have syntax so you can say "SRST(something)" to get a linkable label at the top of a section, but nothing more precisely targeted than that. (I think that ultimately we should consider splitting out "build manpages" and "build HTML docs" into completely separate sphinx doc source trees and sphinx-doc runs (with build time fiddling for where they share content), because sphinx really really doesn't want "different docs formats are different content" and it shows up in various places including this "it's hard to define a label in content that's shared between manpages and HTML" one.)

Quoted 9 lines
Quoted 4 lines

There's an argument that the deprecation warning could look at the option the user actually provided and emit the exact right new option to use instead. But I don't think that's something we've ever done before for deprecations.

Essentially we have three distinct places with info - the deprecation message at runtime, the deprecated.rst docs, and the qemu.1 manual page. It is a trade off between how much effort we want to put into each area.

One of these is the one that by definition every user who needs to update their command lines will see, though.

Quoted 3 lines

For humans I anticipated they'd be mostly using -monitor / -qmp convenience options, with -mon mostly used by machines which are already familiar with -object usage already.

Mmm. I'm not quite sure why my scripts use -mon + -chardev rather than '-monitor tcp:...'.

thanks
-- PMM

#36 lore raw

[PULL 32/35] monitor: add support for auto-deleting monitors upon close

In reply to Markus Armbruster

From: Daniel P. Berrangé <[email protected]>

The default monitor is usually a long lived object that will exist for the entire lifetime of the VM. A monitor can only service a single client at a time though, and so it might be desirable to hotplug additional monitors at runtime for specific tasks. If doing that, however, there is a need to remove the monitor when it is no longer needed.

A use case for hotplugging a monitor can involve a user wishing to spawn an ad hoc script that uses a temporary monitor. The script can ask the management application to hotplug a monitor and pass back a pre-opened FD using SCM_RIGHTS. In this case the lifetime of the script is not tied to the management application and thus it is desirable to have automatic cleanup when the script exits.

Allowing a client to run "object-del" against its own monitor adds complex edge cases, as it would be desirable to send the QMP response despite the monitor sending it being deleted. Doing "object-del" alone will also result in orphaning a character device backend instance, as there is no opportunity to run the companion "chardev-del" command.

A simpler way to ensure cleanup is to add the concept of auto-deleting monitor objects. Specifically when the "CHR_EVENT_CLOSED" event is emitted, the equivalent of "object-del" + "chardev-del" can be run internally. Since the transient client has already droppped its monitor connection, there is no synchronization to be concerned about with sending QMP replies. There is still some internal synchronization needed, however, between the character device event callback and the bottom-half that runs the delete. There is a chance that an incoming client connection may arise before the bottom-half runs, which has to be checked. Once the monitor object is deleted, the event callback is unregistered from the character device, eliminating any further races before the character device is fully deleted.

This is implemented via a new "close-action=none|delete" property on the 'monitor-qmp' object. This concept could be extended with further actions in future, for example:

* close-action=shutdown - graceful guest shutdown
* close-action=terminate - immediate guest poweroff
* close-action=stop - pause guest CPUs while the monitor is not connected to any client

This is left as an exercise for future interested contributors.

Message-ID: <[email protected]>

[Commit message typos fixed]
---
 qapi/qom.json                                 | 22 ++++-
 monitor/monitor-internal.h                    |  3 +
 monitor/qmp.c                                 | 80 ++++++++++++++++++
 .../generic/test_monitor_hotplug.py           | 83 ++++++++++++++++++-
 4 files changed, 183 insertions(+), 5 deletions(-)
qapi/qom.json +21 -1
index 33a827b9fa..d96cc5aa21 100644
@@ -1213,6 +1213,22 @@
   'base': 'MonitorProperties',
   'data': { '*readline': 'bool' } }
 
+
+##
+# @MonitorQMPCloseAction:
+#
+# Action to take when the character device backend is closed.
+#
+# @none: take no action
+#
+# @delete: delete both the 'monitor-qmp' object and its associated
+#     character device backend object
+#
+# Since: 11.1
+##
+{ 'enum': 'MonitorQMPCloseAction',
+  'data': ['none', 'delete'] }
+
 ##
 # @MonitorQMPProperties:
 #
@@ -1220,11 +1236,15 @@
 #
 # @pretty: whether to pretty print JSON responses (default: false)
 #
+# @close-action: action to take when the character device backend is
+#     closed (default: none)
+#
 # Since: 11.1
 ##
 { 'struct': 'MonitorQMPProperties',
   'base': 'MonitorProperties',
-  'data': { '*pretty': 'bool' } }
+  'data': { '*pretty': 'bool',
+            '*close-action': 'MonitorQMPCloseAction' } }
 
 ##
 # @ObjectType:
monitor/monitor-internal.h +3 -0
index 5522e05464..23829f32f9 100644
@@ -28,6 +28,7 @@
 #include "chardev/char-fe.h"
 #include "monitor/monitor.h"
 #include "qapi/qapi-types-control.h"
+#include "qapi/qapi-types-qom.h"
 #include "qapi/qmp-registry.h"
 #include "qobject/json-parser.h"
 #include "qemu/readline.h"
@@ -178,7 +179,9 @@ struct MonitorQMP {
     Monitor parent_obj;
     JSONMessageParser parser;
     bool pretty;
+    MonitorQMPCloseAction close_action;
     bool setup_pending; /* iothread BH has not yet set up chardev handlers */
+    bool delete_pending; /* close_action has started 'delete' process */
     /*
      * When a client connects, we're in capabilities negotiation mode.
      * @commands is &qmp_cap_negotiation_commands then.  When command
monitor/qmp.c +80 -0

115 lines not on this page · raw message

tests/functional/generic/test_monitor_hotplug.py +79 -4

101 lines not on this page · raw message

Signature · 1 line
2.54.0
#37 lore raw

[PULL 02/35] monitor: replace 'common' with 'parent_obj' in MonitorHMP

In reply to Markus Armbruster

From: Daniel P. Berrangé <[email protected]>

The field name 'parent_obj' is standard practice for QOM structs so align the HMP monitor.

Message-ID: <[email protected]>

---
 monitor/monitor-internal.h |  2 +-
 monitor/hmp-cmds.c         |  2 +-
 monitor/hmp.c              | 43 ++++++++++++++++++++------------------
 monitor/monitor.c          |  6 +++---
 monitor/qmp-cmds.c         | 10 ++++-----
 ui/ui-hmp-cmds.c           |  2 +-
 6 files changed, 34 insertions(+), 31 deletions(-)
monitor/monitor-internal.h +1 -1
index a5c4aba306..eb301ea796 100644
@@ -128,7 +128,7 @@ struct Monitor {
 };
 
 struct MonitorHMP {
-    Monitor common;
+    Monitor parent_obj;
     bool use_readline;
     /*
      * State used only in the thread "owning" the monitor.
monitor/hmp-cmds.c +1 -1
index 443b8c785d..e139caeba9 100644
@@ -287,7 +287,7 @@ void hmp_info_sync_profile(Monitor *mon, const QDict *qdict)
 
 void hmp_info_history(Monitor *mon, const QDict *qdict)
 {
-    MonitorHMP *hmp_mon = container_of(mon, MonitorHMP, common);
+    MonitorHMP *hmp_mon = container_of(mon, MonitorHMP, parent_obj);
     int i;
     const char *str;
 
monitor/hmp.c +23 -20

130 lines not on this page · raw message

monitor/monitor.c +3 -3
index 00b93ed612..2a1b511ff4 100644
@@ -132,7 +132,7 @@ static inline bool monitor_is_hmp_non_interactive(const Monitor *mon)
         return false;
     }
 
-    return !monitor_uses_readline(container_of(mon, MonitorHMP, common));
+    return !monitor_uses_readline(container_of(mon, MonitorHMP, parent_obj));
 }
 
 static gboolean monitor_unblocked(void *do_not_use, GIOCondition cond,
@@ -542,7 +542,7 @@ static void monitor_accept_input(void *opaque)
 
     qemu_mutex_lock(&mon->mon_lock);
     if (!monitor_is_qmp(mon) && mon->reset_seen) {
-        MonitorHMP *hmp_mon = container_of(mon, MonitorHMP, common);
+        MonitorHMP *hmp_mon = container_of(mon, MonitorHMP, parent_obj);
         assert(hmp_mon->rs);
         readline_restart(hmp_mon->rs);
         qemu_mutex_unlock(&mon->mon_lock);
@@ -627,7 +627,7 @@ void monitor_data_destroy(Monitor *mon)
     if (monitor_is_qmp(mon)) {
         monitor_data_destroy_qmp(container_of(mon, MonitorQMP, common));
     } else {
-        readline_free(container_of(mon, MonitorHMP, common)->rs);
+        readline_free(container_of(mon, MonitorHMP, parent_obj)->rs);
     }
     g_string_free(mon->outbuf, true);
     qemu_mutex_destroy(&mon->mon_lock);
monitor/qmp-cmds.c +5 -5
index 0c409c27dc..aa9ee8a391 100644
@@ -168,10 +168,10 @@ char *qmp_human_monitor_command(const char *command_line, bool has_cpu_index,
     char *output = NULL;
     MonitorHMP hmp = {};
 
-    monitor_data_init(&hmp.common, false, true, false);
+    monitor_data_init(&hmp.parent_obj, false, true, false);
 
     if (has_cpu_index) {
-        int ret = monitor_set_cpu(&hmp.common, cpu_index);
+        int ret = monitor_set_cpu(&hmp.parent_obj, cpu_index);
         if (ret < 0) {
             error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "cpu-index",
                        "a CPU number");
@@ -181,12 +181,12 @@ char *qmp_human_monitor_command(const char *command_line, bool has_cpu_index,
 
     handle_hmp_command(&hmp, command_line);
 
-    WITH_QEMU_LOCK_GUARD(&hmp.common.mon_lock) {
-        output = g_strdup(hmp.common.outbuf->str);
+    WITH_QEMU_LOCK_GUARD(&hmp.parent_obj.mon_lock) {
+        output = g_strdup(hmp.parent_obj.outbuf->str);
     }
 
 out:
-    monitor_data_destroy(&hmp.common);
+    monitor_data_destroy(&hmp.parent_obj);
     return output;
 }
 
ui/ui-hmp-cmds.c +1 -1
index ee3e731d07..06f4030ce4 100644
@@ -343,7 +343,7 @@ void hmp_change_vnc(Monitor *mon, const char *device, const char *target,
         return;
     }
     if (!arg) {
-        MonitorHMP *hmp_mon = container_of(mon, MonitorHMP, common);
+        MonitorHMP *hmp_mon = container_of(mon, MonitorHMP, parent_obj);
         monitor_read_password(hmp_mon, hmp_change_read_arg, NULL);
     } else {
         qmp_change_vnc_password(arg, errp);
Signature · 1 line
2.54.0
#38 lore raw

[PULL 10/35] monitor: remove 'skip_flush' field

In reply to Markus Armbruster

From: Daniel P. Berrangé <[email protected]>

The 'skip_flush' field is set on the dummy throwaway HMP monitor object created by QMP's 'human-monitor-command', as an indication not to try to write data to the chardev. Instead the QMP command impl will grab the data straight out of the in-memory buffer.

The flag is redundant, however, as the monitor code could instead simply check the 'fe_is_open' field on the CharFrontend, which will be false in the same scenarios that 'skip_flush' is true.

Message-ID: <[email protected]>

---
 monitor/monitor-internal.h |  4 +---
 monitor/hmp.c              |  2 +-
 monitor/monitor.c          | 11 +++++++----
 monitor/qmp-cmds.c         |  2 +-
 monitor/qmp.c              |  2 +-
 5 files changed, 11 insertions(+), 10 deletions(-)
monitor/monitor-internal.h +1 -3
index 145d52fd71..d34f9be139 100644
@@ -112,7 +112,6 @@ struct Monitor {
     CharFrontend chr;
     int suspend_cnt;            /* Needs to be accessed atomically */
     bool is_qmp;
-    bool skip_flush;
     bool use_io_thread;
 
     char *mon_cpu_path;
@@ -194,8 +193,7 @@ extern QemuMutex monitor_lock;
 extern MonitorList mon_list;
 
 void monitor_complete(Monitor *mon, Error **errp);
-void monitor_data_init(Monitor *mon, bool is_qmp, bool skip_flush,
-                       bool use_io_thread);
+void monitor_data_init(Monitor *mon, bool is_qmp, bool use_io_thread);
 void monitor_data_destroy(Monitor *mon);
 int monitor_can_read(void *opaque);
 void monitor_list_append(Monitor *mon);
monitor/hmp.c +1 -1
index 54fd25f220..5644c9c4f5 100644
@@ -1590,7 +1590,7 @@ void monitor_new_hmp(const char *id, const char *chardev_id,
         return;
     }
 
-    monitor_data_init(&mon->parent_obj, false, false, false);
+    monitor_data_init(&mon->parent_obj, false, false);
 
     if (mon->use_readline) {
         mon->rs = readline_init(monitor_readline_printf,
monitor/monitor.c +7 -4
index 1648946c92..db9243410a 100644
@@ -190,7 +190,12 @@ void monitor_flush_locked(Monitor *mon)
     size_t len;
     const char *buf;
 
-    if (mon->skip_flush) {
+    /*
+     * When used by QMP human-monitor-command, no chardev
+     * will be connected, as we want to just collect the
+     * output in the buffer
+     */
+    if (!mon->chr.fe_is_open) {
         return;
     }
 
@@ -644,8 +649,7 @@ static void monitor_iothread_init(void)
     mon_iothread = iothread_create("mon_iothread", &error_abort);
 }
 
-void monitor_data_init(Monitor *mon, bool is_qmp, bool skip_flush,
-                       bool use_io_thread)
+void monitor_data_init(Monitor *mon, bool is_qmp, bool use_io_thread)
 {
     if (use_io_thread && !mon_iothread) {
         monitor_iothread_init();
@@ -653,7 +657,6 @@ void monitor_data_init(Monitor *mon, bool is_qmp, bool skip_flush,
     qemu_mutex_init(&mon->mon_lock);
     mon->is_qmp = is_qmp;
     mon->outbuf = g_string_new(NULL);
-    mon->skip_flush = skip_flush;
     mon->use_io_thread = use_io_thread;
 }
 
monitor/qmp-cmds.c +1 -1
index bfde769ef0..0d9adad288 100644
@@ -168,7 +168,7 @@ char *qmp_human_monitor_command(const char *command_line, bool has_cpu_index,
     char *output = NULL;
     MonitorHMP *hmp = MONITOR_HMP(object_new(TYPE_MONITOR_HMP));
 
-    monitor_data_init(&hmp->parent_obj, false, true, false);
+    monitor_data_init(&hmp->parent_obj, false, false);
 
     if (has_cpu_index) {
         int ret = monitor_set_cpu(&hmp->parent_obj, cpu_index);
monitor/qmp.c +1 -1
index d7adb9ba8b..b300886f33 100644
@@ -572,7 +572,7 @@ void monitor_new_qmp(const char *id, const char *chardev_id,
     qemu_chr_fe_set_echo(&mon->parent_obj.chr, true);
 
     /* Note: we run QMP monitor in I/O thread when @chr supports that */
-    monitor_data_init(&mon->parent_obj, true, false,
+    monitor_data_init(&mon->parent_obj, true,
                       qemu_chr_has_feature(mon->parent_obj.chr.chr,
                                            QEMU_CHAR_FEATURE_GCONTEXT));
 
Signature · 1 line
2.54.0
#39 lore raw

[PULL 16/35] monitor: use dynamic cast in monitor_qmp_requests_pop_any_with_lock

In reply to Markus Armbruster

From: Daniel P. Berrangé <[email protected]>

This eliminates a use of monitor_is_qmp() from the QMP coroutine dispatch path.

Message-ID: <[email protected]>

---
 monitor/qmp.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)
monitor/qmp.c +3 -2
index 8bbe25d8de..bd3e6f8375 100644
@@ -277,11 +277,12 @@ static QMPRequest *monitor_qmp_requests_pop_any_with_lock(void)
     MonitorQMP *qmp_mon;
 
     QTAILQ_FOREACH(mon, &mon_list, entry) {
-        if (!monitor_is_qmp(mon)) {
+        qmp_mon = MONITOR_QMP(
+            object_dynamic_cast(OBJECT(mon), TYPE_MONITOR_QMP));
+        if (!qmp_mon) {
             continue;
         }
 
-        qmp_mon = container_of(mon, MonitorQMP, parent_obj);
         qemu_mutex_lock(&qmp_mon->qmp_queue_lock);
         req_obj = g_queue_pop_head(qmp_mon->qmp_requests);
         if (req_obj) {
Signature · 1 line
2.54.0
#40 lore raw

[PULL 14/35] monitor: use class methods for monitor_accept_input

In reply to Markus Armbruster

From: Daniel P. Berrangé <[email protected]>

This removes the need for using monitor_is_qmp() to check the subclass type, which is an anti-pattern.

Message-ID: <[email protected]>

---
 monitor/monitor-internal.h |  5 +++++
 monitor/hmp.c              | 16 ++++++++++++++++
 monitor/monitor.c          | 12 +++---------
 3 files changed, 24 insertions(+), 9 deletions(-)
monitor/monitor-internal.h +5 -0
index 763b5c9625..592f146331 100644
@@ -116,6 +116,11 @@ struct MonitorClass {
      * notifications back to the client
      */
     void (*emit_event)(Monitor *mon, QAPIEvent event, QDict *qdict);
+    /*
+     * If non-NULL, perform any actions needed to prepare
+     * the monitor to accept further client input
+     */
+    void (*accept_input)(Monitor *mon);
 };
 
 struct Monitor {
monitor/hmp.c +16 -0
index f9252387c4..4636165d0b 100644
@@ -70,6 +70,7 @@ static void monitor_hmp_set_readline(Object *obj, bool val, Error **errp)
 
 int monitor_hmp_vprintf(Monitor *mon, const char *fmt, va_list ap)
     G_GNUC_PRINTF(2, 0);
+static void monitor_hmp_accept_input(Monitor *mon);
 
 static void monitor_hmp_class_init(ObjectClass *cls, const void *data)
 {
@@ -80,6 +81,7 @@ static void monitor_hmp_class_init(ObjectClass *cls, const void *data)
                                    monitor_hmp_set_readline);
 
     moncls->vprintf = monitor_hmp_vprintf;
+    moncls->accept_input = monitor_hmp_accept_input;
 }
 
 static void monitor_hmp_init(Object *obj)
@@ -100,6 +102,20 @@ int monitor_hmp_vprintf(Monitor *mon, const char *fmt, va_list ap)
     return monitor_puts(mon, buf);
 }
 
+static void monitor_hmp_accept_input(Monitor *mon)
+{
+    qemu_mutex_lock(&mon->mon_lock);
+    if (mon->reset_seen) {
+        MonitorHMP *hmp = MONITOR_HMP(mon);
+        assert(hmp->rs);
+        readline_restart(hmp->rs);
+        qemu_mutex_unlock(&mon->mon_lock);
+        readline_show_prompt(hmp->rs);
+    } else {
+        qemu_mutex_unlock(&mon->mon_lock);
+    }
+}
+
 static void monitor_command_cb(void *opaque, const char *cmdline,
                                void *readline_opaque)
 {
monitor/monitor.c +3 -9
index 90cfb59c66..6e63e7a5c7 100644
@@ -578,16 +578,10 @@ int monitor_suspend(Monitor *mon)
 static void monitor_accept_input(void *opaque)
 {
     Monitor *mon = opaque;
+    MonitorClass *cls = MONITOR_GET_CLASS(mon);
 
-    qemu_mutex_lock(&mon->mon_lock);
-    if (!monitor_is_qmp(mon) && mon->reset_seen) {
-        MonitorHMP *hmp_mon = container_of(mon, MonitorHMP, parent_obj);
-        assert(hmp_mon->rs);
-        readline_restart(hmp_mon->rs);
-        qemu_mutex_unlock(&mon->mon_lock);
-        readline_show_prompt(hmp_mon->rs);
-    } else {
-        qemu_mutex_unlock(&mon->mon_lock);
+    if (cls->accept_input) {
+        cls->accept_input(mon);
     }
 
     qemu_chr_fe_accept_input(&mon->chr);
Signature · 1 line
2.54.0