diff options
Diffstat (limited to 'monitor/qmp.c')
| -rw-r--r-- | monitor/qmp.c | 44 |
1 files changed, 36 insertions, 8 deletions
diff --git a/monitor/qmp.c b/monitor/qmp.c index 8f91af32be..43880fa623 100644 --- a/monitor/qmp.c +++ b/monitor/qmp.c @@ -79,7 +79,7 @@ static void monitor_qmp_cleanup_queue_and_resume(MonitorQMP *mon) qemu_mutex_lock(&mon->qmp_queue_lock); /* - * Same condition as in monitor_qmp_bh_dispatcher(), but before + * Same condition as in monitor_qmp_dispatcher_co(), but before * removing an element from the queue (hence no `- 1`). * Also, the queue should not be empty either, otherwise the * monitor hasn't been suspended yet (or was already resumed). @@ -113,6 +113,7 @@ void qmp_send_response(MonitorQMP *mon, const QDict *rsp) json = qobject_to_json_pretty(data, mon->pretty); assert(json != NULL); + trace_monitor_qmp_respond(mon, json->str); g_string_append_c(json, '\n'); monitor_puts(&mon->common, json->str); @@ -213,7 +214,7 @@ void coroutine_fn monitor_qmp_dispatcher_co(void *data) { QMPRequest *req_obj = NULL; QDict *rsp; - bool need_resume; + bool oob_enabled; MonitorQMP *mon; while (true) { @@ -251,6 +252,9 @@ void coroutine_fn monitor_qmp_dispatcher_co(void *data) } } + trace_monitor_qmp_in_band_dequeue(req_obj, + req_obj->mon->qmp_requests->length); + if (qatomic_xchg(&qmp_dispatcher_co_busy, true) == true) { /* * Someone rescheduled us (probably because a new requests @@ -269,11 +273,32 @@ void coroutine_fn monitor_qmp_dispatcher_co(void *data) aio_co_schedule(qemu_get_aio_context(), qmp_dispatcher_co); qemu_coroutine_yield(); + /* + * @req_obj has a request, we hold req_obj->mon->qmp_queue_lock + */ + mon = req_obj->mon; - /* qmp_oob_enabled() might change after "qmp_capabilities" */ - need_resume = !qmp_oob_enabled(mon) || - mon->qmp_requests->length == QMP_REQ_QUEUE_LEN_MAX - 1; + + /* + * We need to resume the monitor if handle_qmp_command() + * suspended it. Two cases: + * 1. OOB enabled: mon->qmp_requests has no more space + * Resume right away, so that OOB commands can get executed while + * this request is being processed. + * 2. OOB disabled: always + * Resume only after we're done processing the request, + * We need to save qmp_oob_enabled() for later, because + * qmp_qmp_capabilities() can change it. + */ + oob_enabled = qmp_oob_enabled(mon); + if (oob_enabled + && mon->qmp_requests->length == QMP_REQ_QUEUE_LEN_MAX - 1) { + monitor_resume(&mon->common); + } + qemu_mutex_unlock(&mon->qmp_queue_lock); + + /* Process request */ if (req_obj->req) { if (trace_event_get_state(TRACE_MONITOR_QMP_CMD_IN_BAND)) { QDict *qdict = qobject_to(QDict, req_obj->req); @@ -287,16 +312,17 @@ void coroutine_fn monitor_qmp_dispatcher_co(void *data) monitor_qmp_dispatch(mon, req_obj->req); } else { assert(req_obj->err); + trace_monitor_qmp_err_in_band(error_get_pretty(req_obj->err)); rsp = qmp_error_response(req_obj->err); req_obj->err = NULL; monitor_qmp_respond(mon, rsp); qobject_unref(rsp); } - if (need_resume) { - /* Pairs with the monitor_suspend() in handle_qmp_command() */ + if (!oob_enabled) { monitor_resume(&mon->common); } + qmp_request_free(req_obj); /* @@ -349,7 +375,7 @@ static void handle_qmp_command(void *opaque, QObject *req, Error *err) /* * Suspend the monitor when we can't queue more requests after - * this one. Dequeuing in monitor_qmp_bh_dispatcher() or + * this one. Dequeuing in monitor_qmp_dispatcher_co() or * monitor_qmp_cleanup_queue_and_resume() will resume it. * Note that when OOB is disabled, we queue at most one command, * for backward compatibility. @@ -364,6 +390,8 @@ static void handle_qmp_command(void *opaque, QObject *req, Error *err) * handled in time order. Ownership for req_obj, req, * etc. will be delivered to the handler side. */ + trace_monitor_qmp_in_band_enqueue(req_obj, mon, + mon->qmp_requests->length); assert(mon->qmp_requests->length < QMP_REQ_QUEUE_LEN_MAX); g_queue_push_tail(mon->qmp_requests, req_obj); qemu_mutex_unlock(&mon->qmp_queue_lock); |