From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([208.118.235.92]:56476) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1UdJo9-0003gq-DU for qemu-devel@nongnu.org; Fri, 17 May 2013 08:30:55 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1UdJo4-0002ky-0s for qemu-devel@nongnu.org; Fri, 17 May 2013 08:30:49 -0400 Received: from mx1.redhat.com ([209.132.183.28]:62149) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1UdJo3-0002kl-OD for qemu-devel@nongnu.org; Fri, 17 May 2013 08:30:43 -0400 Date: Fri, 17 May 2013 08:30:38 -0400 From: Luiz Capitulino Message-ID: <20130517083038.3a0c1472@redhat.com> In-Reply-To: <5195A457.9050402@linux.vnet.ibm.com> References: <1366968675-1451-1-git-send-email-xiawenc@linux.vnet.ibm.com> <1366968675-1451-8-git-send-email-xiawenc@linux.vnet.ibm.com> <20130426144657.GB7648@stefanha-thinkpad.redhat.com> <20130429150541.298db151@redhat.com> <5181C9D4.4000905@linux.vnet.ibm.com> <20130502080206.21df203f@redhat.com> <51832636.1020900@linux.vnet.ibm.com> <518710E7.5060103@linux.vnet.ibm.com> <20130506092224.18dbac32@redhat.com> <5192EE9D.5030604@linux.vnet.ibm.com> <20130515082848.0ec7ca4c@redhat.com> <519442D1.8070402@linux.vnet.ibm.com> <20130516081740.6c7ee91c@redhat.com> <5195A457.9050402@linux.vnet.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Subject: Re: [Qemu-devel] [PATCH 7/7] block: dump to monitor for bdrv_snapshot_dump() and bdrv_image_info_dump() List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Wenchao Xia Cc: kwolf@redhat.com, phrdina@redhat.com, Stefan Hajnoczi , qemu-devel@nongnu.org, armbru@redhat.com, pbonzini@redhat.com On Fri, 17 May 2013 11:30:31 +0800 Wenchao Xia wrote: > =E4=BA=8E 2013-5-16 20:17, Luiz Capitulino =E5=86=99=E9=81=93: > > On Thu, 16 May 2013 10:22:09 +0800 > > Wenchao Xia wrote: > > > >> =E4=BA=8E 2013-5-15 20:28, Luiz Capitulino =E5=86=99=E9=81=93: > >>> On Wed, 15 May 2013 10:10:37 +0800 > >>> Wenchao Xia wrote: > >>> > >>>> =E4=BA=8E 2013-5-6 21:22, Luiz Capitulino =E5=86=99=E9=81=93: > >>>>> On Mon, 06 May 2013 10:09:43 +0800 > >>>>> Wenchao Xia wrote: > >>>>> > >>>>>> =E4=BA=8E 2013-5-3 10:51, Wenchao Xia =E5=86=99=E9=81=93: > >>>>>>> =E4=BA=8E 2013-5-2 20:02, Luiz Capitulino =E5=86=99=E9=81=93: > >>>>>>>> On Thu, 02 May 2013 10:05:08 +0800 > >>>>>>>> Wenchao Xia wrote: > >>>>>>>> > >>>>>>>>> =E4=BA=8E 2013-4-30 3:05, Luiz Capitulino =E5=86=99=E9=81=93: > >>>>>>>>>> On Fri, 26 Apr 2013 16:46:57 +0200 > >>>>>>>>>> Stefan Hajnoczi wrote: > >>>>>>>>>> > >>>>>>>>>>> On Fri, Apr 26, 2013 at 05:31:15PM +0800, Wenchao Xia wrote: > >>>>>>>>>>>> @@ -2586,10 +2585,12 @@ void do_info_snapshots(Monitor *mon,= const > >>>>>>>>>>>> QDict *qdict) > >>>>>>>>>>>> } > >>>>>>>>>>>> > >>>>>>>>>>>> if (total > 0) { > >>>>>>>>>>>> - monitor_printf(mon, "%s\n", bdrv_snapshot_dump(buf, > >>>>>>>>>>>> sizeof(buf), NULL)); > >>>>>>>>>>>> + bdrv_snapshot_dump(NULL); > >>>>>>>>>>>> + monitor_printf(mon, "\n"); > >>>>>>>>>>> > >>>>>>>>>>> Luiz: any issue with mixing monitor_printf(mon) and > >>>>>>>>>>> monitor_vprintf(cur_mon) calls? I guess there was a reason f= or > >>>>>>>>>>> explicitly passing mon instead of relying on cur_mon. > >>>>>>>>>> > >>>>>>>>>> where are they being mixed? > >>>>>>>>>> > >>>>>>>>> bdrv_snapshot_dump() used a global variable "cur_mon" in= side, > >>>>>>>>> instead > >>>>>>>>> of let caller pass in a explicit montior* "mon", I guess that i= s the > >>>>>>>>> question. > >>>>>>>> > >>>>>>>> I'd have to see the code to tell, but yes, what Stefan described= is the > >>>>>>>> best practice for the Monitor. > >>>>>>>> > >>>>>>> I think this would not be a problem until qemu wants more t= han one > >>>>>>> human monitor console, and then we may require a data structure t= o tell > >>>>>>> where to output the string: stdout, *mon, or even stderr, and > >>>>>>> error_printf() also need to be changed. > >>>>>>> > >>>>>> Luiz, what is your idea? I'd like to respin v2 if no issues = for it. > >>>>> > >>>>> As I said before, I'd have to see the code to tell. But answering y= our comment, > >>>>> the code does support multiple monitors. > >>>>> > >>>> Hi Luiz, > >>>> Sorry to ask again, do you think method above is OK now, waitin= g for > >>>> your confirm. > >>> > >>> Can you point me to the code in question? > >>> > >> Sure, it is > >> > >> + > >> +/* > >> + * Print to current monitor if we have one, else to stdout. It is > >> similar with > >> + * error_printf(). > >> + * TODO just like error_vprintf() > >> + */ > >> +void message_printf(const char *fmt, ...) > >> +{ > >> + va_list ap; > >> + > >> + va_start(ap, fmt); > >> + if (cur_mon) { > >> + monitor_vprintf(cur_mon, fmt, ap); > >> + } else { > >> + vfprintf(stdout, fmt, ap); > >> + } > >> + va_end(ap); > >> +} > >> > >> This function used global variable cur_mon instead of input parame= ter, > >> similar to error_printf(). > > > > Why do you need it? Why can't you you use error_printf() for example? > > > error_printf() will print out to stderr in qemu-img, but stdout is > wanted for those dump info function. You can refactor the code so that you can pass a FILE *stream argument to error_vprintf() and maybe add error_printf_stream()?