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Re: [Qemu-block] [RFC PATCH 10/10] monitor: Split out monitor/core.c
From: |
Dr. David Alan Gilbert |
Subject: |
Re: [Qemu-block] [RFC PATCH 10/10] monitor: Split out monitor/core.c |
Date: |
Fri, 7 Jun 2019 18:29:49 +0100 |
User-agent: |
Mutt/1.11.4 (2019-03-13) |
* Kevin Wolf (address@hidden) wrote:
> Move the monitor core infrastructure from monitor/misc.c to
> monitor/core.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 and code that requires a system emulator or is
> even target-dependent.
>
> 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 <address@hidden>
OK, but can you call it anything other than core.* - I regularly end up
deleting things like that!
Other than that,
Reviewed-by: Dr. David Alan Gilbert <address@hidden>
> ---
> include/monitor/monitor.h | 1 +
> monitor/monitor_int.h | 1 +
> monitor/core.c | 604 ++++++++++++++++++++++++++++++++++++++
> monitor/misc.c | 567 +----------------------------------
> monitor/Makefile.objs | 2 +-
> 5 files changed, 608 insertions(+), 567 deletions(-)
> create mode 100644 monitor/core.c
>
> diff --git a/include/monitor/monitor.h b/include/monitor/monitor.h
> index 8547529e49..b9f8d175ed 100644
> --- a/include/monitor/monitor.h
> +++ b/include/monitor/monitor.h
> @@ -20,6 +20,7 @@ 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_init_qmp(Chardev *chr, int flags);
> void monitor_init_hmp(Chardev *chr, int flags);
> diff --git a/monitor/monitor_int.h b/monitor/monitor_int.h
> index 8c5d95f942..1a7af6a223 100644
> --- a/monitor/monitor_int.h
> +++ b/monitor/monitor_int.h
> @@ -190,6 +190,7 @@ extern mon_cmd_t mon_cmds[];
> 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/core.c b/monitor/core.c
> new file mode 100644
> index 0000000000..1cea56054b
> --- /dev/null
> +++ b/monitor/core.c
> @@ -0,0 +1,604 @@
> +/*
> + * 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_int.h"
> +
> +#include "qapi/error.h"
> +#include "qapi/qapi-emit-events.h"
> +#include "qapi/qmp/qstring.h"
> +
> +#include "qemu/option.h"
> +#include "sysemu/qtest.h"
> +
> +#include "trace-root.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;
> +
> +/**
> + * 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;
> +}
> +
> +
> +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();
> + }
> + memset(mon, 0, sizeof(Monitor));
> + 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)) {
> + MonitorQMP *qmp_mon = container_of(mon, MonitorQMP, common);
> + monitor_data_destroy_qmp(qmp_mon);
> + } else {
> + MonitorHMP *hmp_mon = container_of(mon, MonitorHMP, common);
> + readline_free(hmp_mon->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/misc.c b/monitor/misc.c
> index 408d11e1fe..1f60f31c95 100644
> --- a/monitor/misc.c
> +++ b/monitor/misc.c
> @@ -117,43 +117,13 @@ 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 mon_cmd_t info_cmds[];
>
> __thread Monitor *cur_mon;
> @@ -161,32 +131,6 @@ __thread Monitor *cur_mon;
> static void monitor_command_cb(void *opaque, const char *cmdline,
> void *readline_opaque);
>
> -/**
> - * 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?
> */
> @@ -220,355 +164,6 @@ int monitor_read_password(MonitorHMP *mon, ReadLineFunc
> *readline_func,
> }
>
>
> -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();
> - }
> - memset(mon, 0, sizeof(Monitor));
> - 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)) {
> - MonitorQMP *qmp_mon = container_of(mon, MonitorQMP, common);
> - monitor_data_destroy_qmp(qmp_mon);
> - } else {
> - MonitorHMP *hmp_mon = container_of(mon, MonitorHMP, common);
> - readline_free(hmp_mon->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)
> {
> @@ -2738,13 +2333,6 @@ 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);
> -}
> -
> static void monitor_command_cb(void *opaque, const char *cmdline,
> void *readline_opaque)
> {
> @@ -2755,60 +2343,6 @@ static void monitor_command_cb(void *opaque, const
> char *cmdline,
> monitor_resume(&mon->common);
> }
>
> -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)
> {
> @@ -2828,27 +2362,12 @@ static void sortcmdlist(void)
> qsort((void *)info_cmds, array_num, elem_size, 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);
> }
>
> /*
> @@ -2873,90 +2392,6 @@ int error_vprintf_unless_qmp(const char *fmt, va_list
> 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/Makefile.objs b/monitor/Makefile.objs
> index 48c73eed51..c8dff5e4b5 100644
> --- a/monitor/Makefile.objs
> +++ b/monitor/Makefile.objs
> @@ -1,2 +1,2 @@
> obj-y += misc.o
> -common-obj-y += qmp.o hmp.o
> +common-obj-y += core.o qmp.o hmp.o
> --
> 2.20.1
>
--
Dr. David Alan Gilbert / address@hidden / Manchester, UK
- Re: [Qemu-block] [RFC PATCH 04/10] monitor: Create MonitorHMP with readline state, (continued)
- [Qemu-block] [RFC PATCH 06/10] Move monitor.c to monitor/misc.c, Kevin Wolf, 2019/06/07
- [Qemu-block] [RFC PATCH 07/10] monitor: Create monitor_int.h with common definitions, Kevin Wolf, 2019/06/07
- [Qemu-block] [RFC PATCH 08/10] monitor: Split out monitor/qmp.c, Kevin Wolf, 2019/06/07
- [Qemu-block] [RFC PATCH 03/10] monitor: Make MonitorQMP a child class of Monitor, Kevin Wolf, 2019/06/07
- [Qemu-block] [RFC PATCH 10/10] monitor: Split out monitor/core.c, Kevin Wolf, 2019/06/07
- Re: [Qemu-block] [RFC PATCH 10/10] monitor: Split out monitor/core.c,
Dr. David Alan Gilbert <=
- Re: [Qemu-block] [RFC PATCH 10/10] monitor: Split out monitor/core.c, Dr. David Alan Gilbert, 2019/06/07
- [Qemu-block] [RFC PATCH 09/10] monitor: Split out monitor/hmp.c, Kevin Wolf, 2019/06/07
- Re: [Qemu-block] [Qemu-devel] [RFC PATCH 00/10] monitor: Split monitor.c in core/HMP/QMP/misc, Daniel P . Berrangé, 2019/06/07