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From: Anthony Liguori <anthony@codemonkey.ws>
To: "Krumme, Chris" <Chris.Krumme@windriver.com>
Cc: Ian Molton <ian.molton@collabora.co.uk>, qemu-devel@nongnu.org
Subject: Re: [Qemu-devel] Socket reconnection.
Date: Tue, 01 Dec 2009 12:54:42 -0600	[thread overview]
Message-ID: <4B156672.1010008@codemonkey.ws> (raw)
In-Reply-To: <58BD0469C48A7443A479A13D101685E30380B88A@ala-mail09.corp.ad.wrs.com>

Krumme, Chris wrote:
> Hello Ian,
>
> Since you did not inline your source I will paste in a chunk:
>
>
> @@ -2030,10 +2036,18 @@ static void tcp_chr_read(void *opaque)
>          if (s->listen_fd >= 0) {
>              qemu_set_fd_handler(s->listen_fd, tcp_chr_accept, NULL,
> chr);
>          }
> -        qemu_set_fd_handler(s->fd, NULL, NULL, NULL);
> +        if (!s->reconnect)
> +            qemu_set_fd_handler(s->fd, NULL, NULL, NULL);
>          closesocket(s->fd);
>          s->fd = -1;
> -        qemu_chr_event(chr, CHR_EVENT_CLOSED);
> +        if (!s->reconnect) {
> +            qemu_chr_event(chr, CHR_EVENT_CLOSED);
> +        } else {
> +            do {
> +                sleep(s->reconnect);
> +            } while(!qemu_chr_connect_socket(s));
> +            qemu_chr_event(chr, CHR_EVENT_RECONNECTED);
> +        }
>      } else if (size > 0) {
>          if (s->do_telnetopt)
>              tcp_chr_process_IAC_bytes(chr, s, buf, &size);
>
>
> Should you be introducing a while sleep loop into Qemu here?
>
> I would think you should be returning 'no data', maybe after trying
> once.
>
> Hope this helps.
>
> Chris
>   

sleep() in qemu is very, very wrong.  It will pause the guest's 
execution and all sorts of badness can ensue.

The right thing to do is set a timer and not generate data while 
disconnected.  I still am not confident this is really a great thing to do.

Regards,

Anthony Liguori

  parent reply	other threads:[~2009-12-01 18:54 UTC|newest]

Thread overview: 22+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-11-26  0:31 [Qemu-devel] Socket reconnection Ian Molton
2009-11-26  9:21 ` Gerd Hoffmann
2009-11-27  9:01 ` Jamie Lokier
2009-12-01 11:55   ` Ian Molton
2009-12-06 14:32     ` Jamie Lokier
2009-12-06 16:33       ` Ian Molton
2009-12-07  2:29         ` Jamie Lokier
2009-12-07  9:29           ` Ian Molton
2009-11-30 17:18 ` Anthony Liguori
2009-12-01 11:54   ` Ian Molton
2009-12-01 14:38     ` Krumme, Chris
2009-12-01 18:29       ` Ian Molton
2009-12-01 18:54       ` Anthony Liguori [this message]
2009-12-02 10:40         ` Ian Molton
2009-12-02 12:04           ` [Qemu-devel] " Jan Kiszka
2009-12-02 19:56           ` [Qemu-devel] " Anthony Liguori
2009-12-02 22:35           ` Krumme, Chris
2009-12-03 10:04             ` Ian Molton
2009-12-03 10:23               ` Kevin Wolf
2009-12-03 14:22               ` Anthony Liguori
2009-12-03 18:37                 ` [Qemu-devel] [PATCH]Socket reconnection Ian Molton
2009-12-05 22:03                   ` Ian Molton

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