From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:43498) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1WvTWR-0000OA-WE for qemu-devel@nongnu.org; Fri, 13 Jun 2014 11:36:12 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1WvTWN-0003BM-EE for qemu-devel@nongnu.org; Fri, 13 Jun 2014 11:36:07 -0400 Received: from smtp.citrix.com ([66.165.176.89]:25661) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1WvTWN-0003BG-7x for qemu-devel@nongnu.org; Fri, 13 Jun 2014 11:36:03 -0400 Message-ID: <539B1A5C.80104@citrix.com> Date: Fri, 13 Jun 2014 17:35:56 +0200 From: =?UTF-8?B?Um9nZXIgUGF1IE1vbm7DqQ==?= MIME-Version: 1.0 References: <1400860669-21593-1-git-send-email-roger.pau@citrix.com> <1400860669-21593-4-git-send-email-roger.pau@citrix.com> In-Reply-To: <1400860669-21593-4-git-send-email-roger.pau@citrix.com> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8bit Subject: Re: [Qemu-devel] [PATCH v2 3/3] serial: poll the serial console with G_IO_HUP List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org, xen-devel@lists.xenproject.org Cc: Paolo Bonzini , Peter Crosthwaite , Michael Tokarev , =?UTF-8?B?QW5kcmVhcyBGw6RyYmVy?= Ping? On 23/05/14 17:57, Roger Pau Monne wrote: > On FreeBSD polling a master pty while the other end is not connected > with G_IO_OUT only results in an endless wait. This is different from > the Linux behaviour, that returns immediately. In order to demonstrate > this, I have the following example code: > > http://xenbits.xen.org/people/royger/test_poll.c > > When executed on Linux: > > $ ./test_poll > In callback > > On FreeBSD instead, the callback never gets called: > > $ ./test_poll > > So, in order to workaround this, poll the source with G_IO_HUP (which > makes the code behave the same way on both Linux and FreeBSD). > > Signed-off-by: Roger Pau Monné > Cc: Peter Crosthwaite > Cc: Michael Tokarev > Cc: "Andreas Färber" > Cc: Paolo Bonzini > Cc: xen-devel@lists.xenproject.org > --- > Changes since v1: > - Fix other users of qemu_chr_fe_add_watch to use G_IO_HUP. > --- > hw/char/serial.c | 2 +- > hw/char/virtio-console.c | 3 ++- > hw/usb/redirect.c | 2 +- > monitor.c | 2 +- > 4 files changed, 5 insertions(+), 4 deletions(-) > > diff --git a/hw/char/serial.c b/hw/char/serial.c > index f4d167f..2a2c9e5 100644 > --- a/hw/char/serial.c > +++ b/hw/char/serial.c > @@ -246,7 +246,7 @@ static gboolean serial_xmit(GIOChannel *chan, GIOCondition cond, void *opaque) > serial_receive1(s, &s->tsr, 1); > } else if (qemu_chr_fe_write(s->chr, &s->tsr, 1) != 1) { > if (s->tsr_retry >= 0 && s->tsr_retry < MAX_XMIT_RETRY && > - qemu_chr_fe_add_watch(s->chr, G_IO_OUT, serial_xmit, s) > 0) { > + qemu_chr_fe_add_watch(s->chr, G_IO_OUT|G_IO_HUP, serial_xmit, s) > 0) { > s->tsr_retry++; > return FALSE; > } > diff --git a/hw/char/virtio-console.c b/hw/char/virtio-console.c > index 6c8be0f..38e290a 100644 > --- a/hw/char/virtio-console.c > +++ b/hw/char/virtio-console.c > @@ -69,7 +69,8 @@ static ssize_t flush_buf(VirtIOSerialPort *port, > if (!k->is_console) { > virtio_serial_throttle_port(port, true); > if (!vcon->watch) { > - vcon->watch = qemu_chr_fe_add_watch(vcon->chr, G_IO_OUT, > + vcon->watch = qemu_chr_fe_add_watch(vcon->chr, > + G_IO_OUT|G_IO_HUP, > chr_write_unblocked, vcon); > } > } > diff --git a/hw/usb/redirect.c b/hw/usb/redirect.c > index 287a505..06e757d 100644 > --- a/hw/usb/redirect.c > +++ b/hw/usb/redirect.c > @@ -284,7 +284,7 @@ static int usbredir_write(void *priv, uint8_t *data, int count) > r = qemu_chr_fe_write(dev->cs, data, count); > if (r < count) { > if (!dev->watch) { > - dev->watch = qemu_chr_fe_add_watch(dev->cs, G_IO_OUT, > + dev->watch = qemu_chr_fe_add_watch(dev->cs, G_IO_OUT|G_IO_HUP, > usbredir_write_unblocked, dev); > } > if (r < 0) { > diff --git a/monitor.c b/monitor.c > index 593679a..ae1c539 100644 > --- a/monitor.c > +++ b/monitor.c > @@ -304,7 +304,7 @@ void monitor_flush(Monitor *mon) > mon->outbuf = tmp; > } > if (mon->watch == 0) { > - mon->watch = qemu_chr_fe_add_watch(mon->chr, G_IO_OUT, > + mon->watch = qemu_chr_fe_add_watch(mon->chr, G_IO_OUT|G_IO_HUP, > monitor_unblocked, mon); > } > } >