From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:49010) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gX1Ue-0000u4-Nk for qemu-devel@nongnu.org; Wed, 12 Dec 2018 05:11:53 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1gX1Uc-0003NK-On for qemu-devel@nongnu.org; Wed, 12 Dec 2018 05:11:52 -0500 Received: from mx1.redhat.com ([209.132.183.28]:45982) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1gX1Uc-0003MD-Hs for qemu-devel@nongnu.org; Wed, 12 Dec 2018 05:11:50 -0500 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 D2CFE3002C6A for ; Wed, 12 Dec 2018 10:11:49 +0000 (UTC) From: Markus Armbruster Date: Wed, 12 Dec 2018 11:11:36 +0100 Message-Id: <20181212101145.3496-3-armbru@redhat.com> In-Reply-To: <20181212101145.3496-1-armbru@redhat.com> References: <20181212101145.3496-1-armbru@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Subject: [Qemu-devel] [PULL 02/11] monitor: accept chardev input from iothread List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: =?UTF-8?q?Marc-Andr=C3=A9=20Lureau?= From: Marc-Andr=C3=A9 Lureau Chardev backends may not handle safely IO events from concurrent threads (may not handle I/O events from concurrent threads safely, only the write path is since commit > 9005b2a7589540a3733b3abdcfbccfe7746cd1a1). Better to wake up the chardev from the monitor IO thread if it's being used as the chardev context. Unify code paths by using a BH in all cases. Drop the now redundant aio_notify() call. Clean up control flow not to rely on mon->use_io_thread implying monitor_is_qmp(mon). Signed-off-by: Marc-Andr=C3=A9 Lureau Reviewed-by: Peter Xu Reviewed-by: Markus Armbruster Message-Id: <20181205203737.9011-3-marcandre.lureau@redhat.com> Signed-off-by: Markus Armbruster --- monitor.c | 29 +++++++++++++++++++---------- 1 file changed, 19 insertions(+), 10 deletions(-) diff --git a/monitor.c b/monitor.c index d531e8ccc9..79afe99079 100644 --- a/monitor.c +++ b/monitor.c @@ -4297,7 +4297,7 @@ int monitor_suspend(Monitor *mon) =20 atomic_inc(&mon->suspend_cnt); =20 - if (monitor_is_qmp(mon) && mon->use_io_thread) { + 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. @@ -4309,6 +4309,13 @@ int monitor_suspend(Monitor *mon) return 0; } =20 +static void monitor_accept_input(void *opaque) +{ + Monitor *mon =3D opaque; + + qemu_chr_fe_accept_input(&mon->chr); +} + void monitor_resume(Monitor *mon) { if (monitor_is_hmp_non_interactive(mon)) { @@ -4316,20 +4323,22 @@ void monitor_resume(Monitor *mon) } =20 if (atomic_dec_fetch(&mon->suspend_cnt) =3D=3D 0) { - if (monitor_is_qmp(mon)) { - /* - * For QMP monitors that are running in the I/O thread, - * let's kick the thread in case it's sleeping. - */ - if (mon->use_io_thread) { - aio_notify(iothread_get_aio_context(mon_iothread)); - } + AioContext *ctx; + + if (mon->use_io_thread) { + ctx =3D iothread_get_aio_context(mon_iothread); } else { + ctx =3D qemu_get_aio_context(); + } + + if (!monitor_is_qmp(mon)) { assert(mon->rs); readline_show_prompt(mon->rs); } - qemu_chr_fe_accept_input(&mon->chr); + + aio_bh_schedule_oneshot(ctx, monitor_accept_input, mon); } + trace_monitor_suspend(mon, -1); } =20 --=20 2.17.2