From patchwork Mon Jun 17 18:49:00 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Markus Armbruster X-Patchwork-Id: 1117388 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (mailfrom) smtp.mailfrom=nongnu.org (client-ip=209.51.188.17; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=) Authentication-Results: ozlabs.org; dmarc=fail (p=none dis=none) header.from=redhat.com Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 45SL4Q4rmRz9sNC for ; Tue, 18 Jun 2019 04:55:02 +1000 (AEST) Received: from localhost ([::1]:51156 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.86_2) (envelope-from ) id 1hcwmS-0000SV-NQ for incoming@patchwork.ozlabs.org; Mon, 17 Jun 2019 14:55:00 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:40578) by lists.gnu.org with esmtp (Exim 4.86_2) (envelope-from ) id 1hcwhA-0001wR-Jf for qemu-devel@nongnu.org; Mon, 17 Jun 2019 14:49:37 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1hcwh5-0007wU-BL for qemu-devel@nongnu.org; Mon, 17 Jun 2019 14:49:32 -0400 Received: from mx1.redhat.com ([209.132.183.28]:42430) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1hcwh4-0007lc-Uc for qemu-devel@nongnu.org; Mon, 17 Jun 2019 14:49:27 -0400 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 76DB87FDCA for ; Mon, 17 Jun 2019 18:49:08 +0000 (UTC) Received: from blackfin.pond.sub.org (ovpn-117-177.ams2.redhat.com [10.36.117.177]) by smtp.corp.redhat.com (Postfix) with ESMTPS id A2C7C19746; Mon, 17 Jun 2019 18:49:07 +0000 (UTC) Received: by blackfin.pond.sub.org (Postfix, from userid 1000) id 80291113301F; Mon, 17 Jun 2019 20:49:03 +0200 (CEST) From: Markus Armbruster To: qemu-devel@nongnu.org Date: Mon, 17 Jun 2019 20:49:00 +0200 Message-Id: <20190617184903.19436-14-armbru@redhat.com> In-Reply-To: <20190617184903.19436-1-armbru@redhat.com> References: <20190617184903.19436-1-armbru@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.27]); Mon, 17 Jun 2019 18:49:08 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 209.132.183.28 Subject: [Qemu-devel] [PULL 13/16] monitor: Split out monitor/monitor.c X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Kevin Wolf Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: "Qemu-devel" From: Kevin Wolf Move the monitor core infrastructure from monitor/misc.c to monitor/monitor.c. This is code that can be shared for all targets, so compile it only once. What remains in monitor/misc.c after this patch is mostly monitor command implementations (which could move to hmp-cmds.c or qmp-cmds.c later) and code that requires a system emulator or is even target-dependent (including HMP command completion code). The amount of function and particularly extern variables in monitor_int.h is probably a bit larger than it needs to be, but this way no non-trivial code modifications are needed. The interfaces between all monitor parts can be cleaned up later. Signed-off-by: Kevin Wolf Message-Id: <20190613153405.24769-13-kwolf@redhat.com> Reviewed-by: Markus Armbruster [Superfluous #include dropped] Signed-off-by: Markus Armbruster --- MAINTAINERS | 2 + include/monitor/monitor.h | 1 + monitor/Makefile.objs | 2 +- monitor/misc.c | 598 +---------------------------------- monitor/monitor-internal.h | 1 + monitor/monitor.c | 633 +++++++++++++++++++++++++++++++++++++ monitor/trace-events | 2 +- 7 files changed, 640 insertions(+), 599 deletions(-) create mode 100644 monitor/monitor.c diff --git a/MAINTAINERS b/MAINTAINERS index 15f21c35e0..d32c5c2313 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -1920,6 +1920,7 @@ M: Dr. David Alan Gilbert S: Maintained F: monitor/monitor-internal.h F: monitor/misc.c +F: monitor/monitor.c F: monitor/hmp* F: hmp.h F: hmp-commands*.hx @@ -2044,6 +2045,7 @@ S: Supported F: monitor/monitor-internal.h F: monitor/qmp* F: monitor/misc.c +F: monitor/monitor.c F: docs/devel/*qmp-* F: docs/interop/*qmp-* F: scripts/qmp/ diff --git a/include/monitor/monitor.h b/include/monitor/monitor.h index f9d30e1d78..44ac43df34 100644 --- a/include/monitor/monitor.h +++ b/include/monitor/monitor.h @@ -19,6 +19,7 @@ typedef struct MonitorHMP MonitorHMP; bool monitor_cur_is_qmp(void); void monitor_init_globals(void); +void monitor_init_globals_core(void); void monitor_init(Chardev *chr, int flags); void monitor_cleanup(void); diff --git a/monitor/Makefile.objs b/monitor/Makefile.objs index bea8838acc..e91a8581cd 100644 --- a/monitor/Makefile.objs +++ b/monitor/Makefile.objs @@ -1,3 +1,3 @@ obj-y += misc.o -common-obj-y += qmp.o hmp.o +common-obj-y += monitor.o qmp.o hmp.o common-obj-y += qmp-cmds.o hmp-cmds.o diff --git a/monitor/misc.c b/monitor/misc.c index 5756d25590..002aba1030 100644 --- a/monitor/misc.c +++ b/monitor/misc.c @@ -54,7 +54,6 @@ #include "qapi/qmp/qerror.h" #include "qapi/qmp/qstring.h" #include "qom/object_interfaces.h" -#include "trace.h" #include "trace/control.h" #include "monitor/hmp-target.h" #ifdef CONFIG_TRACE_SIMPLE @@ -71,7 +70,6 @@ #include "qapi/error.h" #include "qapi/qmp-event.h" #include "qapi/qapi-introspect.h" -#include "sysemu/qtest.h" #include "sysemu/cpus.h" #include "qemu/cutils.h" #include "tcg/tcg.h" @@ -107,427 +105,15 @@ struct MonFdset { QLIST_ENTRY(MonFdset) next; }; -/* - * To prevent flooding clients, events can be throttled. The - * throttling is calculated globally, rather than per-Monitor - * instance. - */ -typedef struct MonitorQAPIEventState { - QAPIEvent event; /* Throttling state for this event type and... */ - QDict *data; /* ... data, see qapi_event_throttle_equal() */ - QEMUTimer *timer; /* Timer for handling delayed events */ - QDict *qdict; /* Delayed event (if any) */ -} MonitorQAPIEventState; - -typedef struct { - int64_t rate; /* Minimum time (in ns) between two events */ -} MonitorQAPIEventConf; - -/* Shared monitor I/O thread */ -IOThread *mon_iothread; - -/* Bottom half to dispatch the requests received from I/O thread */ -QEMUBH *qmp_dispatcher_bh; - /* QMP checker flags */ #define QMP_ACCEPT_UNKNOWNS 1 -/* Protects mon_list, monitor_qapi_event_state, monitor_destroyed. */ -QemuMutex monitor_lock; -static GHashTable *monitor_qapi_event_state; -MonitorList mon_list; -static bool monitor_destroyed; - /* Protects mon_fdsets */ static QemuMutex mon_fdsets_lock; static QLIST_HEAD(, MonFdset) mon_fdsets; -int mon_refcount; - static HMPCommand hmp_info_cmds[]; -__thread Monitor *cur_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 Monitor *mon) -{ - return mon->flags & MONITOR_USE_READLINE; -} - -static inline bool monitor_is_hmp_non_interactive(const Monitor *mon) -{ - return !monitor_is_qmp(mon) && !monitor_uses_readline(mon); -} - -/* - * Return the clock to use for recording an event's time. - * It's QEMU_CLOCK_REALTIME, except for qtests it's - * QEMU_CLOCK_VIRTUAL, to support testing rate limits. - * Beware: result is invalid before configure_accelerator(). - */ -static inline QEMUClockType monitor_get_event_clock(void) -{ - return qtest_enabled() ? QEMU_CLOCK_VIRTUAL : QEMU_CLOCK_REALTIME; -} - -/** - * Is the current monitor, if any, a QMP monitor? - */ -bool monitor_cur_is_qmp(void) -{ - return cur_mon && monitor_is_qmp(cur_mon); -} - -static void monitor_flush_locked(Monitor *mon); - -static gboolean monitor_unblocked(GIOChannel *chan, GIOCondition cond, - void *opaque) -{ - Monitor *mon = opaque; - - qemu_mutex_lock(&mon->mon_lock); - mon->out_watch = 0; - monitor_flush_locked(mon); - qemu_mutex_unlock(&mon->mon_lock); - return FALSE; -} - -/* Caller must hold mon->mon_lock */ -static void monitor_flush_locked(Monitor *mon) -{ - int rc; - size_t len; - const char *buf; - - if (mon->skip_flush) { - return; - } - - buf = qstring_get_str(mon->outbuf); - len = qstring_get_length(mon->outbuf); - - if (len && !mon->mux_out) { - rc = qemu_chr_fe_write(&mon->chr, (const uint8_t *) buf, len); - if ((rc < 0 && errno != EAGAIN) || (rc == len)) { - /* all flushed or error */ - qobject_unref(mon->outbuf); - mon->outbuf = qstring_new(); - return; - } - if (rc > 0) { - /* partial write */ - QString *tmp = qstring_from_str(buf + rc); - qobject_unref(mon->outbuf); - mon->outbuf = tmp; - } - if (mon->out_watch == 0) { - mon->out_watch = - qemu_chr_fe_add_watch(&mon->chr, G_IO_OUT | G_IO_HUP, - monitor_unblocked, mon); - } - } -} - -void monitor_flush(Monitor *mon) -{ - qemu_mutex_lock(&mon->mon_lock); - monitor_flush_locked(mon); - qemu_mutex_unlock(&mon->mon_lock); -} - -/* flush at every end of line */ -int monitor_puts(Monitor *mon, const char *str) -{ - int i; - char c; - - qemu_mutex_lock(&mon->mon_lock); - for (i = 0; str[i]; i++) { - c = str[i]; - if (c == '\n') { - qstring_append_chr(mon->outbuf, '\r'); - } - qstring_append_chr(mon->outbuf, c); - if (c == '\n') { - monitor_flush_locked(mon); - } - } - qemu_mutex_unlock(&mon->mon_lock); - - return i; -} - -int monitor_vprintf(Monitor *mon, const char *fmt, va_list ap) -{ - char *buf; - int n; - - if (!mon) - return -1; - - if (monitor_is_qmp(mon)) { - return -1; - } - - buf = g_strdup_vprintf(fmt, ap); - n = monitor_puts(mon, buf); - g_free(buf); - return n; -} - -int monitor_printf(Monitor *mon, const char *fmt, ...) -{ - int ret; - - va_list ap; - va_start(ap, fmt); - ret = monitor_vprintf(mon, fmt, ap); - va_end(ap); - return ret; -} - -static MonitorQAPIEventConf monitor_qapi_event_conf[QAPI_EVENT__MAX] = { - /* Limit guest-triggerable events to 1 per second */ - [QAPI_EVENT_RTC_CHANGE] = { 1000 * SCALE_MS }, - [QAPI_EVENT_WATCHDOG] = { 1000 * SCALE_MS }, - [QAPI_EVENT_BALLOON_CHANGE] = { 1000 * SCALE_MS }, - [QAPI_EVENT_QUORUM_REPORT_BAD] = { 1000 * SCALE_MS }, - [QAPI_EVENT_QUORUM_FAILURE] = { 1000 * SCALE_MS }, - [QAPI_EVENT_VSERPORT_CHANGE] = { 1000 * SCALE_MS }, -}; - -/* - * Broadcast an event to all monitors. - * @qdict is the event object. Its member "event" must match @event. - * Caller must hold monitor_lock. - */ -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; - } - - qmp_mon = container_of(mon, MonitorQMP, common); - if (qmp_mon->commands != &qmp_cap_negotiation_commands) { - qmp_send_response(qmp_mon, qdict); - } - } -} - -static void monitor_qapi_event_handler(void *opaque); - -/* - * Queue a new event for emission to Monitor instances, - * applying any rate limiting if required. - */ -static void -monitor_qapi_event_queue_no_reenter(QAPIEvent event, QDict *qdict) -{ - MonitorQAPIEventConf *evconf; - MonitorQAPIEventState *evstate; - - assert(event < QAPI_EVENT__MAX); - evconf = &monitor_qapi_event_conf[event]; - trace_monitor_protocol_event_queue(event, qdict, evconf->rate); - - qemu_mutex_lock(&monitor_lock); - - if (!evconf->rate) { - /* Unthrottled event */ - monitor_qapi_event_emit(event, qdict); - } else { - QDict *data = qobject_to(QDict, qdict_get(qdict, "data")); - MonitorQAPIEventState key = { .event = event, .data = data }; - - evstate = g_hash_table_lookup(monitor_qapi_event_state, &key); - assert(!evstate || timer_pending(evstate->timer)); - - if (evstate) { - /* - * Timer is pending for (at least) evconf->rate ns after - * last send. Store event for sending when timer fires, - * replacing a prior stored event if any. - */ - qobject_unref(evstate->qdict); - evstate->qdict = qobject_ref(qdict); - } else { - /* - * Last send was (at least) evconf->rate ns ago. - * Send immediately, and arm the timer to call - * monitor_qapi_event_handler() in evconf->rate ns. Any - * events arriving before then will be delayed until then. - */ - int64_t now = qemu_clock_get_ns(monitor_get_event_clock()); - - monitor_qapi_event_emit(event, qdict); - - evstate = g_new(MonitorQAPIEventState, 1); - evstate->event = event; - evstate->data = qobject_ref(data); - evstate->qdict = NULL; - evstate->timer = timer_new_ns(monitor_get_event_clock(), - monitor_qapi_event_handler, - evstate); - g_hash_table_add(monitor_qapi_event_state, evstate); - timer_mod_ns(evstate->timer, now + evconf->rate); - } - } - - qemu_mutex_unlock(&monitor_lock); -} - -void qapi_event_emit(QAPIEvent event, QDict *qdict) -{ - /* - * monitor_qapi_event_queue_no_reenter() is not reentrant: it - * would deadlock on monitor_lock. Work around by queueing - * events in thread-local storage. - * TODO: remove this, make it re-enter safe. - */ - typedef struct MonitorQapiEvent { - QAPIEvent event; - QDict *qdict; - QSIMPLEQ_ENTRY(MonitorQapiEvent) entry; - } MonitorQapiEvent; - static __thread QSIMPLEQ_HEAD(, MonitorQapiEvent) event_queue; - static __thread bool reentered; - MonitorQapiEvent *ev; - - if (!reentered) { - QSIMPLEQ_INIT(&event_queue); - } - - ev = g_new(MonitorQapiEvent, 1); - ev->qdict = qobject_ref(qdict); - ev->event = event; - QSIMPLEQ_INSERT_TAIL(&event_queue, ev, entry); - if (reentered) { - return; - } - - reentered = true; - - while ((ev = QSIMPLEQ_FIRST(&event_queue)) != NULL) { - QSIMPLEQ_REMOVE_HEAD(&event_queue, entry); - monitor_qapi_event_queue_no_reenter(ev->event, ev->qdict); - qobject_unref(ev->qdict); - g_free(ev); - } - - reentered = false; -} - -/* - * This function runs evconf->rate ns after sending a throttled - * event. - * If another event has since been stored, send it. - */ -static void monitor_qapi_event_handler(void *opaque) -{ - MonitorQAPIEventState *evstate = opaque; - MonitorQAPIEventConf *evconf = &monitor_qapi_event_conf[evstate->event]; - - trace_monitor_protocol_event_handler(evstate->event, evstate->qdict); - qemu_mutex_lock(&monitor_lock); - - if (evstate->qdict) { - int64_t now = qemu_clock_get_ns(monitor_get_event_clock()); - - monitor_qapi_event_emit(evstate->event, evstate->qdict); - qobject_unref(evstate->qdict); - evstate->qdict = NULL; - timer_mod_ns(evstate->timer, now + evconf->rate); - } else { - g_hash_table_remove(monitor_qapi_event_state, evstate); - qobject_unref(evstate->data); - timer_free(evstate->timer); - g_free(evstate); - } - - qemu_mutex_unlock(&monitor_lock); -} - -static unsigned int qapi_event_throttle_hash(const void *key) -{ - const MonitorQAPIEventState *evstate = key; - unsigned int hash = evstate->event * 255; - - if (evstate->event == QAPI_EVENT_VSERPORT_CHANGE) { - hash += g_str_hash(qdict_get_str(evstate->data, "id")); - } - - if (evstate->event == QAPI_EVENT_QUORUM_REPORT_BAD) { - hash += g_str_hash(qdict_get_str(evstate->data, "node-name")); - } - - return hash; -} - -static gboolean qapi_event_throttle_equal(const void *a, const void *b) -{ - const MonitorQAPIEventState *eva = a; - const MonitorQAPIEventState *evb = b; - - if (eva->event != evb->event) { - return FALSE; - } - - if (eva->event == QAPI_EVENT_VSERPORT_CHANGE) { - return !strcmp(qdict_get_str(eva->data, "id"), - qdict_get_str(evb->data, "id")); - } - - if (eva->event == QAPI_EVENT_QUORUM_REPORT_BAD) { - return !strcmp(qdict_get_str(eva->data, "node-name"), - qdict_get_str(evb->data, "node-name")); - } - - return TRUE; -} - -static void monitor_qapi_event_init(void) -{ - monitor_qapi_event_state = g_hash_table_new(qapi_event_throttle_hash, - qapi_event_throttle_equal); -} - -static void monitor_iothread_init(void); - -void monitor_data_init(Monitor *mon, int flags, bool skip_flush, - bool use_io_thread) -{ - if (use_io_thread && !mon_iothread) { - monitor_iothread_init(); - } - qemu_mutex_init(&mon->mon_lock); - mon->outbuf = qstring_new(); - mon->skip_flush = skip_flush; - mon->use_io_thread = use_io_thread; - mon->flags = flags; -} - -static 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)); - } else { - readline_free(container_of(mon, MonitorHMP, common)->rs); - } - qobject_unref(mon->outbuf); - qemu_mutex_destroy(&mon->mon_lock); -} - char *qmp_human_monitor_command(const char *command_line, bool has_cpu_index, int64_t cpu_index, Error **errp) { @@ -2728,67 +2314,6 @@ void loadvm_completion(ReadLineState *rs, int nb_args, const char *str) } } -int monitor_can_read(void *opaque) -{ - Monitor *mon = opaque; - - return !atomic_mb_read(&mon->suspend_cnt); -} - -int monitor_suspend(Monitor *mon) -{ - if (monitor_is_hmp_non_interactive(mon)) { - return -ENOTTY; - } - - atomic_inc(&mon->suspend_cnt); - - if (mon->use_io_thread) { - /* - * Kick I/O thread to make sure this takes effect. It'll be - * evaluated again in prepare() of the watch object. - */ - aio_notify(iothread_get_aio_context(mon_iothread)); - } - - trace_monitor_suspend(mon, 1); - return 0; -} - -static void monitor_accept_input(void *opaque) -{ - Monitor *mon = opaque; - - qemu_chr_fe_accept_input(&mon->chr); -} - -void monitor_resume(Monitor *mon) -{ - if (monitor_is_hmp_non_interactive(mon)) { - return; - } - - if (atomic_dec_fetch(&mon->suspend_cnt) == 0) { - AioContext *ctx; - - if (mon->use_io_thread) { - ctx = iothread_get_aio_context(mon_iothread); - } else { - ctx = qemu_get_aio_context(); - } - - if (!monitor_is_qmp(mon)) { - MonitorHMP *hmp_mon = container_of(mon, MonitorHMP, common); - assert(hmp_mon->rs); - readline_show_prompt(hmp_mon->rs); - } - - aio_bh_schedule_oneshot(ctx, monitor_accept_input, mon); - } - - trace_monitor_suspend(mon, -1); -} - static int compare_mon_cmd(const void *a, const void *b) { @@ -2806,135 +2331,14 @@ static void sortcmdlist(void) compare_mon_cmd); } -static void monitor_iothread_init(void) -{ - mon_iothread = iothread_create("mon_iothread", &error_abort); -} - void monitor_init_globals(void) { + monitor_init_globals_core(); monitor_init_qmp_commands(); - monitor_qapi_event_init(); sortcmdlist(); - qemu_mutex_init(&monitor_lock); qemu_mutex_init(&mon_fdsets_lock); - - /* - * The dispatcher BH must run in the main loop thread, since we - * have commands assuming that context. It would be nice to get - * rid of those assumptions. - */ - qmp_dispatcher_bh = aio_bh_new(iohandler_get_aio_context(), - monitor_qmp_bh_dispatcher, - NULL); } -/* - * Print to current monitor if we have one, else to stderr. - */ -int error_vprintf(const char *fmt, va_list ap) -{ - if (cur_mon && !monitor_cur_is_qmp()) { - return monitor_vprintf(cur_mon, fmt, ap); - } - return vfprintf(stderr, fmt, ap); -} - -int error_vprintf_unless_qmp(const char *fmt, va_list ap) -{ - if (!cur_mon) { - return vfprintf(stderr, fmt, ap); - } - if (!monitor_cur_is_qmp()) { - return monitor_vprintf(cur_mon, fmt, ap); - } - return -1; -} - -void monitor_list_append(Monitor *mon) -{ - qemu_mutex_lock(&monitor_lock); - /* - * This prevents inserting new monitors during monitor_cleanup(). - * A cleaner solution would involve the main thread telling other - * threads to terminate, waiting for their termination. - */ - if (!monitor_destroyed) { - QTAILQ_INSERT_HEAD(&mon_list, mon, entry); - mon = NULL; - } - qemu_mutex_unlock(&monitor_lock); - - if (mon) { - monitor_data_destroy(mon); - g_free(mon); - } -} - -void monitor_init(Chardev *chr, int flags) -{ - if (flags & MONITOR_USE_CONTROL) { - monitor_init_qmp(chr, flags); - } else { - monitor_init_hmp(chr, flags); - } -} - -void monitor_cleanup(void) -{ - /* - * We need to explicitly stop the I/O thread (but not destroy it), - * clean up the monitor resources, then destroy the I/O thread since - * we need to unregister from chardev below in - * monitor_data_destroy(), and chardev is not thread-safe yet - */ - if (mon_iothread) { - iothread_stop(mon_iothread); - } - - /* Flush output buffers and destroy monitors */ - qemu_mutex_lock(&monitor_lock); - monitor_destroyed = true; - while (!QTAILQ_EMPTY(&mon_list)) { - Monitor *mon = QTAILQ_FIRST(&mon_list); - QTAILQ_REMOVE(&mon_list, mon, entry); - /* Permit QAPI event emission from character frontend release */ - qemu_mutex_unlock(&monitor_lock); - monitor_flush(mon); - monitor_data_destroy(mon); - qemu_mutex_lock(&monitor_lock); - g_free(mon); - } - qemu_mutex_unlock(&monitor_lock); - - /* QEMUBHs needs to be deleted before destroying the I/O thread */ - qemu_bh_delete(qmp_dispatcher_bh); - qmp_dispatcher_bh = NULL; - if (mon_iothread) { - iothread_destroy(mon_iothread); - mon_iothread = NULL; - } -} - -QemuOptsList qemu_mon_opts = { - .name = "mon", - .implied_opt_name = "chardev", - .head = QTAILQ_HEAD_INITIALIZER(qemu_mon_opts.head), - .desc = { - { - .name = "mode", - .type = QEMU_OPT_STRING, - },{ - .name = "chardev", - .type = QEMU_OPT_STRING, - },{ - .name = "pretty", - .type = QEMU_OPT_BOOL, - }, - { /* end of list */ } - }, -}; - HotpluggableCPUList *qmp_query_hotpluggable_cpus(Error **errp) { MachineState *ms = MACHINE(qdev_get_machine()); diff --git a/monitor/monitor-internal.h b/monitor/monitor-internal.h index 10fda7d97c..b4996c14ac 100644 --- a/monitor/monitor-internal.h +++ b/monitor/monitor-internal.h @@ -167,6 +167,7 @@ void monitor_init_hmp(Chardev *chr, int flags); int monitor_puts(Monitor *mon, const char *str); void monitor_data_init(Monitor *mon, int flags, bool skip_flush, bool use_io_thread); +void monitor_data_destroy(Monitor *mon); int monitor_can_read(void *opaque); void monitor_list_append(Monitor *mon); void monitor_fdsets_cleanup(void); diff --git a/monitor/monitor.c b/monitor/monitor.c new file mode 100644 index 0000000000..db3d5ece99 --- /dev/null +++ b/monitor/monitor.c @@ -0,0 +1,633 @@ +/* + * QEMU monitor + * + * Copyright (c) 2003-2004 Fabrice Bellard + * + * Permission is hereby granted, free of charge, to any person obtaining a copy + * of this software and associated documentation files (the "Software"), to deal + * in the Software without restriction, including without limitation the rights + * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell + * copies of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in + * all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, + * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN + * THE SOFTWARE. + */ + +#include "qemu/osdep.h" +#include "monitor-internal.h" +#include "qapi/error.h" +#include "qapi/qapi-emit-events.h" +#include "qapi/qmp/qdict.h" +#include "qapi/qmp/qstring.h" +#include "qemu/error-report.h" +#include "qemu/option.h" +#include "sysemu/qtest.h" +#include "trace.h" + +/* + * To prevent flooding clients, events can be throttled. The + * throttling is calculated globally, rather than per-Monitor + * instance. + */ +typedef struct MonitorQAPIEventState { + QAPIEvent event; /* Throttling state for this event type and... */ + QDict *data; /* ... data, see qapi_event_throttle_equal() */ + QEMUTimer *timer; /* Timer for handling delayed events */ + QDict *qdict; /* Delayed event (if any) */ +} MonitorQAPIEventState; + +typedef struct { + int64_t rate; /* Minimum time (in ns) between two events */ +} MonitorQAPIEventConf; + +/* Shared monitor I/O thread */ +IOThread *mon_iothread; + +/* Bottom half to dispatch the requests received from I/O thread */ +QEMUBH *qmp_dispatcher_bh; + +/* Protects mon_list, monitor_qapi_event_state, monitor_destroyed. */ +QemuMutex monitor_lock; +static GHashTable *monitor_qapi_event_state; + +MonitorList mon_list; +int mon_refcount; +static bool monitor_destroyed; + +__thread Monitor *cur_mon; + +/** + * Is the current monitor, if any, a QMP monitor? + */ +bool monitor_cur_is_qmp(void) +{ + return cur_mon && monitor_is_qmp(cur_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 Monitor *mon) +{ + return mon->flags & MONITOR_USE_READLINE; +} + +static inline bool monitor_is_hmp_non_interactive(const Monitor *mon) +{ + return !monitor_is_qmp(mon) && !monitor_uses_readline(mon); +} + +static void monitor_flush_locked(Monitor *mon); + +static gboolean monitor_unblocked(GIOChannel *chan, GIOCondition cond, + void *opaque) +{ + Monitor *mon = opaque; + + qemu_mutex_lock(&mon->mon_lock); + mon->out_watch = 0; + monitor_flush_locked(mon); + qemu_mutex_unlock(&mon->mon_lock); + return FALSE; +} + +/* Caller must hold mon->mon_lock */ +static void monitor_flush_locked(Monitor *mon) +{ + int rc; + size_t len; + const char *buf; + + if (mon->skip_flush) { + return; + } + + buf = qstring_get_str(mon->outbuf); + len = qstring_get_length(mon->outbuf); + + if (len && !mon->mux_out) { + rc = qemu_chr_fe_write(&mon->chr, (const uint8_t *) buf, len); + if ((rc < 0 && errno != EAGAIN) || (rc == len)) { + /* all flushed or error */ + qobject_unref(mon->outbuf); + mon->outbuf = qstring_new(); + return; + } + if (rc > 0) { + /* partial write */ + QString *tmp = qstring_from_str(buf + rc); + qobject_unref(mon->outbuf); + mon->outbuf = tmp; + } + if (mon->out_watch == 0) { + mon->out_watch = + qemu_chr_fe_add_watch(&mon->chr, G_IO_OUT | G_IO_HUP, + monitor_unblocked, mon); + } + } +} + +void monitor_flush(Monitor *mon) +{ + qemu_mutex_lock(&mon->mon_lock); + monitor_flush_locked(mon); + qemu_mutex_unlock(&mon->mon_lock); +} + +/* flush at every end of line */ +int monitor_puts(Monitor *mon, const char *str) +{ + int i; + char c; + + qemu_mutex_lock(&mon->mon_lock); + for (i = 0; str[i]; i++) { + c = str[i]; + if (c == '\n') { + qstring_append_chr(mon->outbuf, '\r'); + } + qstring_append_chr(mon->outbuf, c); + if (c == '\n') { + monitor_flush_locked(mon); + } + } + qemu_mutex_unlock(&mon->mon_lock); + + return i; +} + +int monitor_vprintf(Monitor *mon, const char *fmt, va_list ap) +{ + char *buf; + int n; + + if (!mon) { + return -1; + } + + if (monitor_is_qmp(mon)) { + return -1; + } + + buf = g_strdup_vprintf(fmt, ap); + n = monitor_puts(mon, buf); + g_free(buf); + return n; +} + +int monitor_printf(Monitor *mon, const char *fmt, ...) +{ + int ret; + + va_list ap; + va_start(ap, fmt); + ret = monitor_vprintf(mon, fmt, ap); + va_end(ap); + return ret; +} + +/* + * Print to current monitor if we have one, else to stderr. + */ +int error_vprintf(const char *fmt, va_list ap) +{ + if (cur_mon && !monitor_cur_is_qmp()) { + return monitor_vprintf(cur_mon, fmt, ap); + } + return vfprintf(stderr, fmt, ap); +} + +int error_vprintf_unless_qmp(const char *fmt, va_list ap) +{ + if (!cur_mon) { + return vfprintf(stderr, fmt, ap); + } + if (!monitor_cur_is_qmp()) { + return monitor_vprintf(cur_mon, fmt, ap); + } + return -1; +} + + +static MonitorQAPIEventConf monitor_qapi_event_conf[QAPI_EVENT__MAX] = { + /* Limit guest-triggerable events to 1 per second */ + [QAPI_EVENT_RTC_CHANGE] = { 1000 * SCALE_MS }, + [QAPI_EVENT_WATCHDOG] = { 1000 * SCALE_MS }, + [QAPI_EVENT_BALLOON_CHANGE] = { 1000 * SCALE_MS }, + [QAPI_EVENT_QUORUM_REPORT_BAD] = { 1000 * SCALE_MS }, + [QAPI_EVENT_QUORUM_FAILURE] = { 1000 * SCALE_MS }, + [QAPI_EVENT_VSERPORT_CHANGE] = { 1000 * SCALE_MS }, +}; + +/* + * Return the clock to use for recording an event's time. + * It's QEMU_CLOCK_REALTIME, except for qtests it's + * QEMU_CLOCK_VIRTUAL, to support testing rate limits. + * Beware: result is invalid before configure_accelerator(). + */ +static inline QEMUClockType monitor_get_event_clock(void) +{ + return qtest_enabled() ? QEMU_CLOCK_VIRTUAL : QEMU_CLOCK_REALTIME; +} + +/* + * Broadcast an event to all monitors. + * @qdict is the event object. Its member "event" must match @event. + * Caller must hold monitor_lock. + */ +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; + } + + qmp_mon = container_of(mon, MonitorQMP, common); + if (qmp_mon->commands != &qmp_cap_negotiation_commands) { + qmp_send_response(qmp_mon, qdict); + } + } +} + +static void monitor_qapi_event_handler(void *opaque); + +/* + * Queue a new event for emission to Monitor instances, + * applying any rate limiting if required. + */ +static void +monitor_qapi_event_queue_no_reenter(QAPIEvent event, QDict *qdict) +{ + MonitorQAPIEventConf *evconf; + MonitorQAPIEventState *evstate; + + assert(event < QAPI_EVENT__MAX); + evconf = &monitor_qapi_event_conf[event]; + trace_monitor_protocol_event_queue(event, qdict, evconf->rate); + + qemu_mutex_lock(&monitor_lock); + + if (!evconf->rate) { + /* Unthrottled event */ + monitor_qapi_event_emit(event, qdict); + } else { + QDict *data = qobject_to(QDict, qdict_get(qdict, "data")); + MonitorQAPIEventState key = { .event = event, .data = data }; + + evstate = g_hash_table_lookup(monitor_qapi_event_state, &key); + assert(!evstate || timer_pending(evstate->timer)); + + if (evstate) { + /* + * Timer is pending for (at least) evconf->rate ns after + * last send. Store event for sending when timer fires, + * replacing a prior stored event if any. + */ + qobject_unref(evstate->qdict); + evstate->qdict = qobject_ref(qdict); + } else { + /* + * Last send was (at least) evconf->rate ns ago. + * Send immediately, and arm the timer to call + * monitor_qapi_event_handler() in evconf->rate ns. Any + * events arriving before then will be delayed until then. + */ + int64_t now = qemu_clock_get_ns(monitor_get_event_clock()); + + monitor_qapi_event_emit(event, qdict); + + evstate = g_new(MonitorQAPIEventState, 1); + evstate->event = event; + evstate->data = qobject_ref(data); + evstate->qdict = NULL; + evstate->timer = timer_new_ns(monitor_get_event_clock(), + monitor_qapi_event_handler, + evstate); + g_hash_table_add(monitor_qapi_event_state, evstate); + timer_mod_ns(evstate->timer, now + evconf->rate); + } + } + + qemu_mutex_unlock(&monitor_lock); +} + +void qapi_event_emit(QAPIEvent event, QDict *qdict) +{ + /* + * monitor_qapi_event_queue_no_reenter() is not reentrant: it + * would deadlock on monitor_lock. Work around by queueing + * events in thread-local storage. + * TODO: remove this, make it re-enter safe. + */ + typedef struct MonitorQapiEvent { + QAPIEvent event; + QDict *qdict; + QSIMPLEQ_ENTRY(MonitorQapiEvent) entry; + } MonitorQapiEvent; + static __thread QSIMPLEQ_HEAD(, MonitorQapiEvent) event_queue; + static __thread bool reentered; + MonitorQapiEvent *ev; + + if (!reentered) { + QSIMPLEQ_INIT(&event_queue); + } + + ev = g_new(MonitorQapiEvent, 1); + ev->qdict = qobject_ref(qdict); + ev->event = event; + QSIMPLEQ_INSERT_TAIL(&event_queue, ev, entry); + if (reentered) { + return; + } + + reentered = true; + + while ((ev = QSIMPLEQ_FIRST(&event_queue)) != NULL) { + QSIMPLEQ_REMOVE_HEAD(&event_queue, entry); + monitor_qapi_event_queue_no_reenter(ev->event, ev->qdict); + qobject_unref(ev->qdict); + g_free(ev); + } + + reentered = false; +} + +/* + * This function runs evconf->rate ns after sending a throttled + * event. + * If another event has since been stored, send it. + */ +static void monitor_qapi_event_handler(void *opaque) +{ + MonitorQAPIEventState *evstate = opaque; + MonitorQAPIEventConf *evconf = &monitor_qapi_event_conf[evstate->event]; + + trace_monitor_protocol_event_handler(evstate->event, evstate->qdict); + qemu_mutex_lock(&monitor_lock); + + if (evstate->qdict) { + int64_t now = qemu_clock_get_ns(monitor_get_event_clock()); + + monitor_qapi_event_emit(evstate->event, evstate->qdict); + qobject_unref(evstate->qdict); + evstate->qdict = NULL; + timer_mod_ns(evstate->timer, now + evconf->rate); + } else { + g_hash_table_remove(monitor_qapi_event_state, evstate); + qobject_unref(evstate->data); + timer_free(evstate->timer); + g_free(evstate); + } + + qemu_mutex_unlock(&monitor_lock); +} + +static unsigned int qapi_event_throttle_hash(const void *key) +{ + const MonitorQAPIEventState *evstate = key; + unsigned int hash = evstate->event * 255; + + if (evstate->event == QAPI_EVENT_VSERPORT_CHANGE) { + hash += g_str_hash(qdict_get_str(evstate->data, "id")); + } + + if (evstate->event == QAPI_EVENT_QUORUM_REPORT_BAD) { + hash += g_str_hash(qdict_get_str(evstate->data, "node-name")); + } + + return hash; +} + +static gboolean qapi_event_throttle_equal(const void *a, const void *b) +{ + const MonitorQAPIEventState *eva = a; + const MonitorQAPIEventState *evb = b; + + if (eva->event != evb->event) { + return FALSE; + } + + if (eva->event == QAPI_EVENT_VSERPORT_CHANGE) { + return !strcmp(qdict_get_str(eva->data, "id"), + qdict_get_str(evb->data, "id")); + } + + if (eva->event == QAPI_EVENT_QUORUM_REPORT_BAD) { + return !strcmp(qdict_get_str(eva->data, "node-name"), + qdict_get_str(evb->data, "node-name")); + } + + return TRUE; +} + +int monitor_suspend(Monitor *mon) +{ + if (monitor_is_hmp_non_interactive(mon)) { + return -ENOTTY; + } + + atomic_inc(&mon->suspend_cnt); + + if (mon->use_io_thread) { + /* + * Kick I/O thread to make sure this takes effect. It'll be + * evaluated again in prepare() of the watch object. + */ + aio_notify(iothread_get_aio_context(mon_iothread)); + } + + trace_monitor_suspend(mon, 1); + return 0; +} + +static void monitor_accept_input(void *opaque) +{ + Monitor *mon = opaque; + + qemu_chr_fe_accept_input(&mon->chr); +} + +void monitor_resume(Monitor *mon) +{ + if (monitor_is_hmp_non_interactive(mon)) { + return; + } + + if (atomic_dec_fetch(&mon->suspend_cnt) == 0) { + AioContext *ctx; + + if (mon->use_io_thread) { + ctx = iothread_get_aio_context(mon_iothread); + } else { + ctx = qemu_get_aio_context(); + } + + if (!monitor_is_qmp(mon)) { + MonitorHMP *hmp_mon = container_of(mon, MonitorHMP, common); + assert(hmp_mon->rs); + readline_show_prompt(hmp_mon->rs); + } + + aio_bh_schedule_oneshot(ctx, monitor_accept_input, mon); + } + + trace_monitor_suspend(mon, -1); +} + +int monitor_can_read(void *opaque) +{ + Monitor *mon = opaque; + + return !atomic_mb_read(&mon->suspend_cnt); +} + +void monitor_list_append(Monitor *mon) +{ + qemu_mutex_lock(&monitor_lock); + /* + * This prevents inserting new monitors during monitor_cleanup(). + * A cleaner solution would involve the main thread telling other + * threads to terminate, waiting for their termination. + */ + if (!monitor_destroyed) { + QTAILQ_INSERT_HEAD(&mon_list, mon, entry); + mon = NULL; + } + qemu_mutex_unlock(&monitor_lock); + + if (mon) { + monitor_data_destroy(mon); + g_free(mon); + } +} + +static void monitor_iothread_init(void) +{ + mon_iothread = iothread_create("mon_iothread", &error_abort); +} + +void monitor_data_init(Monitor *mon, int flags, bool skip_flush, + bool use_io_thread) +{ + if (use_io_thread && !mon_iothread) { + monitor_iothread_init(); + } + qemu_mutex_init(&mon->mon_lock); + mon->outbuf = qstring_new(); + mon->skip_flush = skip_flush; + mon->use_io_thread = use_io_thread; + mon->flags = flags; +} + +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)); + } else { + readline_free(container_of(mon, MonitorHMP, common)->rs); + } + qobject_unref(mon->outbuf); + qemu_mutex_destroy(&mon->mon_lock); +} + +void monitor_init(Chardev *chr, int flags) +{ + if (flags & MONITOR_USE_CONTROL) { + monitor_init_qmp(chr, flags); + } else { + monitor_init_hmp(chr, flags); + } +} + +void monitor_cleanup(void) +{ + /* + * We need to explicitly stop the I/O thread (but not destroy it), + * clean up the monitor resources, then destroy the I/O thread since + * we need to unregister from chardev below in + * monitor_data_destroy(), and chardev is not thread-safe yet + */ + if (mon_iothread) { + iothread_stop(mon_iothread); + } + + /* Flush output buffers and destroy monitors */ + qemu_mutex_lock(&monitor_lock); + monitor_destroyed = true; + while (!QTAILQ_EMPTY(&mon_list)) { + Monitor *mon = QTAILQ_FIRST(&mon_list); + QTAILQ_REMOVE(&mon_list, mon, entry); + /* Permit QAPI event emission from character frontend release */ + qemu_mutex_unlock(&monitor_lock); + monitor_flush(mon); + monitor_data_destroy(mon); + qemu_mutex_lock(&monitor_lock); + g_free(mon); + } + qemu_mutex_unlock(&monitor_lock); + + /* QEMUBHs needs to be deleted before destroying the I/O thread */ + qemu_bh_delete(qmp_dispatcher_bh); + qmp_dispatcher_bh = NULL; + if (mon_iothread) { + iothread_destroy(mon_iothread); + mon_iothread = NULL; + } +} + +static void monitor_qapi_event_init(void) +{ + monitor_qapi_event_state = g_hash_table_new(qapi_event_throttle_hash, + qapi_event_throttle_equal); +} + +void monitor_init_globals_core(void) +{ + monitor_qapi_event_init(); + qemu_mutex_init(&monitor_lock); + + /* + * The dispatcher BH must run in the main loop thread, since we + * have commands assuming that context. It would be nice to get + * rid of those assumptions. + */ + qmp_dispatcher_bh = aio_bh_new(iohandler_get_aio_context(), + monitor_qmp_bh_dispatcher, + NULL); +} + +QemuOptsList qemu_mon_opts = { + .name = "mon", + .implied_opt_name = "chardev", + .head = QTAILQ_HEAD_INITIALIZER(qemu_mon_opts.head), + .desc = { + { + .name = "mode", + .type = QEMU_OPT_STRING, + },{ + .name = "chardev", + .type = QEMU_OPT_STRING, + },{ + .name = "pretty", + .type = QEMU_OPT_BOOL, + }, + { /* end of list */ } + }, +}; diff --git a/monitor/trace-events b/monitor/trace-events index 2285d26121..0365ac4d99 100644 --- a/monitor/trace-events +++ b/monitor/trace-events @@ -3,7 +3,7 @@ # hmp.c handle_hmp_command(void *mon, const char *cmdline) "mon %p cmdline: %s" -# misc.c +# monitor.c monitor_protocol_event_handler(uint32_t event, void *qdict) "event=%d data=%p" monitor_protocol_event_emit(uint32_t event, void *data) "event=%d data=%p" monitor_protocol_event_queue(uint32_t event, void *qdict, uint64_t rate) "event=%d data=%p rate=%" PRId64