From nobody Tue Feb 10 12:43:12 2026 Delivered-To: importer@patchew.org Received-SPF: pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) client-ip=208.118.235.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Authentication-Results: mx.zohomail.com; spf=pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org Return-Path: Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) by mx.zohomail.com with SMTPS id 1522077099215198.17286966630002; Mon, 26 Mar 2018 08:11:39 -0700 (PDT) Received: from localhost ([::1]:57272 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1f0TmT-0006UJ-VQ for importer@patchew.org; Mon, 26 Mar 2018 11:11:30 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:54761) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1f0Tkc-00054w-He for qemu-devel@nongnu.org; Mon, 26 Mar 2018 11:09:35 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1f0TkZ-0002g8-Q0 for qemu-devel@nongnu.org; Mon, 26 Mar 2018 11:09:34 -0400 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:57182 helo=mx1.redhat.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1f0TkZ-0002fr-K3 for qemu-devel@nongnu.org; Mon, 26 Mar 2018 11:09:31 -0400 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.rdu2.redhat.com [10.11.54.6]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 4D5FB84256; Mon, 26 Mar 2018 15:09:31 +0000 (UTC) Received: from localhost (ovpn-112-61.ams2.redhat.com [10.36.112.61]) by smtp.corp.redhat.com (Postfix) with ESMTP id D1A08215CDAE; Mon, 26 Mar 2018 15:09:30 +0000 (UTC) From: =?UTF-8?q?Marc-Andr=C3=A9=20Lureau?= To: qemu-devel@nongnu.org Date: Mon, 26 Mar 2018 17:08:41 +0200 Message-Id: <20180326150916.9602-4-marcandre.lureau@redhat.com> In-Reply-To: <20180326150916.9602-1-marcandre.lureau@redhat.com> References: <20180326150916.9602-1-marcandre.lureau@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.78 on 10.11.54.6 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.2]); Mon, 26 Mar 2018 15:09:31 +0000 (UTC) X-Greylist: inspected by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.2]); Mon, 26 Mar 2018 15:09:31 +0000 (UTC) for IP:'10.11.54.6' DOMAIN:'int-mx06.intmail.prod.int.rdu2.redhat.com' HELO:'smtp.corp.redhat.com' FROM:'marcandre.lureau@redhat.com' RCPT:'' Content-Transfer-Encoding: quoted-printable X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 66.187.233.73 Subject: [Qemu-devel] [PATCH v3 03/38] Revert "qmp: isolate responses into io thread" X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Eduardo Habkost , Juan Quintela , Markus Armbruster , "Dr. David Alan Gilbert" , Gerd Hoffmann , Cleber Rosa , =?UTF-8?q?Marc-Andr=C3=A9=20Lureau?= , Michael Roth Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail: RSF_0 Z_629925259 SPT_0 Content-Type: text/plain; charset="utf-8" This reverts commit abe3cd0ff7f774966da6842620806ab7576fe4f3. There is no need to add an additional queue to send the reply to the IOThread, because QMP response is thread safe, and chardev write path is thread safe. It will schedule watcher in the associated IOThread. Signed-off-by: Marc-Andr=C3=A9 Lureau --- monitor.c | 96 +------------------------------------------------------ 1 file changed, 1 insertion(+), 95 deletions(-) diff --git a/monitor.c b/monitor.c index d57bbbb134..59920ea872 100644 --- a/monitor.c +++ b/monitor.c @@ -180,8 +180,6 @@ typedef struct { QemuMutex qmp_queue_lock; /* Input queue that holds all the parsed QMP requests */ GQueue *qmp_requests; - /* Output queue contains all the QMP responses in order */ - GQueue *qmp_responses; } MonitorQMP; =20 /* @@ -208,7 +206,6 @@ struct Monitor { bool skip_flush; bool use_io_thr; =20 - /* We can't access guest memory when holding the lock */ QemuMutex out_lock; QString *outbuf; guint out_watch; @@ -231,8 +228,6 @@ static struct { IOThread *mon_iothread; /* Bottom half to dispatch the requests received from IO thread */ QEMUBH *qmp_dispatcher_bh; - /* Bottom half to deliver the responses back to clients */ - QEMUBH *qmp_respond_bh; } mon_global; =20 /* QMP checker flags */ @@ -422,8 +417,7 @@ int monitor_fprintf(FILE *stream, const char *fmt, ...) return 0; } =20 -static void monitor_json_emitter_raw(Monitor *mon, - QObject *data) +static void monitor_json_emitter(Monitor *mon, const QObject *data) { QString *json; =20 @@ -437,71 +431,6 @@ static void monitor_json_emitter_raw(Monitor *mon, QDECREF(json); } =20 -static void monitor_json_emitter(Monitor *mon, QObject *data) -{ - if (mon->use_io_thr) { - /* - * If using IO thread, we need to queue the item so that IO - * thread will do the rest for us. Take refcount so that - * caller won't free the data (which will be finally freed in - * responder thread). - */ - qobject_incref(data); - qemu_mutex_lock(&mon->qmp.qmp_queue_lock); - g_queue_push_tail(mon->qmp.qmp_responses, (void *)data); - qemu_mutex_unlock(&mon->qmp.qmp_queue_lock); - qemu_bh_schedule(mon_global.qmp_respond_bh); - } else { - /* - * If not using monitor IO thread, then we are in main thread. - * Do the emission right away. - */ - monitor_json_emitter_raw(mon, data); - } -} - -struct QMPResponse { - Monitor *mon; - QObject *data; -}; -typedef struct QMPResponse QMPResponse; - -/* - * Return one QMPResponse. The response is only valid if - * response.data is not NULL. - */ -static QMPResponse monitor_qmp_response_pop_one(void) -{ - Monitor *mon; - QObject *data =3D NULL; - - qemu_mutex_lock(&monitor_lock); - QTAILQ_FOREACH(mon, &mon_list, entry) { - qemu_mutex_lock(&mon->qmp.qmp_queue_lock); - data =3D g_queue_pop_head(mon->qmp.qmp_responses); - qemu_mutex_unlock(&mon->qmp.qmp_queue_lock); - if (data) { - break; - } - } - qemu_mutex_unlock(&monitor_lock); - return (QMPResponse) { .mon =3D mon, .data =3D data }; -} - -static void monitor_qmp_bh_responder(void *opaque) -{ - QMPResponse response; - - while (true) { - response =3D monitor_qmp_response_pop_one(); - if (!response.data) { - break; - } - monitor_json_emitter_raw(response.mon, response.data); - qobject_decref(response.data); - } -} - static MonitorQAPIEventConf monitor_qapi_event_conf[QAPI_EVENT__MAX] =3D { /* Limit guest-triggerable events to 1 per second */ [QAPI_EVENT_RTC_CHANGE] =3D { 1000 * SCALE_MS }, @@ -688,7 +617,6 @@ static void monitor_data_init(Monitor *mon, bool skip_f= lush, mon->skip_flush =3D skip_flush; mon->use_io_thr =3D use_io_thr; mon->qmp.qmp_requests =3D g_queue_new(); - mon->qmp.qmp_responses =3D g_queue_new(); } =20 static void monitor_data_destroy(Monitor *mon) @@ -703,7 +631,6 @@ static void monitor_data_destroy(Monitor *mon) qemu_mutex_destroy(&mon->out_lock); qemu_mutex_destroy(&mon->qmp.qmp_queue_lock); g_queue_free(mon->qmp.qmp_requests); - g_queue_free(mon->qmp.qmp_responses); } =20 char *qmp_human_monitor_command(const char *command_line, bool has_cpu_ind= ex, @@ -4443,15 +4370,6 @@ static void monitor_iothread_init(void) mon_global.qmp_dispatcher_bh =3D aio_bh_new(qemu_get_aio_context(), monitor_qmp_bh_dispatcher, NULL); - - /* - * Unlike the dispatcher BH, this must be run on the monitor IO - * thread, so that monitors that are using IO thread will make - * sure read/write operations are all done on the IO thread. - */ - mon_global.qmp_respond_bh =3D aio_bh_new(monitor_get_aio_context(), - monitor_qmp_bh_responder, - NULL); } =20 void monitor_init_globals(void) @@ -4597,19 +4515,9 @@ void monitor_cleanup(void) */ iothread_stop(mon_global.mon_iothread); =20 - /* - * After we have IOThread to send responses, it's possible that - * when we stop the IOThread there are still replies queued in the - * responder queue. Flush all of them. Note that even after this - * flush it's still possible that out buffer is not flushed. - * It'll be done in below monitor_flush() as the last resort. - */ - monitor_qmp_bh_responder(NULL); - qemu_mutex_lock(&monitor_lock); QTAILQ_FOREACH_SAFE(mon, &mon_list, entry, next) { QTAILQ_REMOVE(&mon_list, mon, entry); - monitor_flush(mon); monitor_data_destroy(mon); g_free(mon); } @@ -4618,8 +4526,6 @@ void monitor_cleanup(void) /* QEMUBHs needs to be deleted before destroying the IOThread. */ qemu_bh_delete(mon_global.qmp_dispatcher_bh); mon_global.qmp_dispatcher_bh =3D NULL; - qemu_bh_delete(mon_global.qmp_respond_bh); - mon_global.qmp_respond_bh =3D NULL; =20 iothread_destroy(mon_global.mon_iothread); mon_global.mon_iothread =3D NULL; --=20 2.17.0.rc1.1.g4c4f2b46a3