From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ben Thomas Subject: Re: [PATCH] 14287 followup - console Date: Wed, 14 Mar 2007 08:40:19 -0400 Message-ID: <45F7ED33.3030507@virtualiron.com> References: Mime-Version: 1.0 Content-Type: multipart/mixed; boundary="------------030100040703010507000809" Return-path: In-Reply-To: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: Keir Fraser Cc: xen-devel@lists.xensource.com List-Id: xen-devel@lists.xenproject.org This is a multi-part message in MIME format. --------------030100040703010507000809 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sounds like a plan... How about this ? -b Keir Fraser wrote: > On 13/3/07 12:24, "Ben Thomas" wrote: > >> Two input sources are inherently capable >> of getting slightly out of sync (or worse). The second reason >> is that syslog can be expensive. In the end, the WYSIWYG and >> cost resulted in the console ring approach. >> >> Would this be more acceptable if it were selectable ? That is, >> come up with a libxc/sysctl mechanism (which should be pretty >> easy) to control the gating of character data to the console ring >> fom guest_console_write ? > > You could add a Xen boot parameter. > > -- Keir > -- ------------------------------------------------------------------------ Ben Thomas Virtual Iron Software bthomas@virtualiron.com Tower 1, Floor 2 978-849-1214 900 Chelmsford Street Lowell, MA 01851 --------------030100040703010507000809 Content-Type: text/x-patch; name="xen-console.patch" Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="xen-console.patch" Add boot option to allow console I/O to be placed into ring buffer This option allows console I/O to be placed into the hypervisor console ring buffer. When enabled, all output to the console device will be reflected in the ring buffer. When disabled (the default), only hypervisor output is available from the ring buffer. Signed-off-by: Ben Thomas (ben@virtualiron.com) diff -r f183e0a4d0c9 docs/src/user.tex --- a/docs/src/user.tex Wed Mar 14 08:32:05 2007 -0400 +++ b/docs/src/user.tex Wed Mar 14 08:35:11 2007 -0400 @@ -3179,6 +3179,11 @@ editing \path{grub.conf}. one of 80x25, 80x28, 80x30, 80x34, 80x43, 80x50, 80x60. \item[ keep ] Keep the VGA console even after domain 0 boots. \end{description} +\item [ console\_to\_ring ] Place guest console output into the + hypervisor console ring buffer. This is disabled by default. + When enabled, both hypervisor output and guest console output + is available from the ring buffer. This can be useful for logging + and/or remote presentation of console data. \item [ sync\_console ] Force synchronous console output. This is useful if you system fails unexpectedly before it has sent all available output to the console. In most cases Xen will diff -r f183e0a4d0c9 xen/drivers/char/console.c --- a/xen/drivers/char/console.c Wed Mar 14 08:32:05 2007 -0400 +++ b/xen/drivers/char/console.c Wed Mar 14 08:32:06 2007 -0400 @@ -48,6 +48,10 @@ static int opt_sync_console; static int opt_sync_console; boolean_param("sync_console", opt_sync_console); +/* console_to_ring: send guest (incl dom 0) console data to console ring */ +static int opt_console_to_ring; +boolean_param("console_to_ring", opt_console_to_ring); + #define CONRING_SIZE 16384 #define CONRING_IDX_MASK(i) ((i)&(CONRING_SIZE-1)) static char conring[CONRING_SIZE]; @@ -328,8 +332,14 @@ static long guest_console_write(XEN_GUES sercon_puts(kbuf); - for ( kptr = kbuf; *kptr != '\0'; kptr++ ) + for ( kptr = kbuf; *kptr != '\0'; kptr++ ) { vga_putchar(*kptr); + if (opt_console_to_ring) + putchar_console_ring(*kptr); + } + + if (opt_console_to_ring) + send_guest_global_virq(dom0, VIRQ_CON_RING); guest_handle_add_offset(buffer, kcount); count -= kcount; --------------030100040703010507000809 Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel --------------030100040703010507000809--