From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([208.118.235.92]:50380) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1UdBNo-0005o2-CY for qemu-devel@nongnu.org; Thu, 16 May 2013 23:31:05 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1UdBNn-0000Hx-84 for qemu-devel@nongnu.org; Thu, 16 May 2013 23:31:04 -0400 Received: from e28smtp06.in.ibm.com ([122.248.162.6]:55441) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1UdBNm-0000Hp-Ki for qemu-devel@nongnu.org; Thu, 16 May 2013 23:31:03 -0400 Received: from /spool/local by e28smtp06.in.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Fri, 17 May 2013 08:54:53 +0530 Received: from d28relay02.in.ibm.com (d28relay02.in.ibm.com [9.184.220.59]) by d28dlp01.in.ibm.com (Postfix) with ESMTP id D2CE6E0054 for ; Fri, 17 May 2013 09:03:22 +0530 (IST) Received: from d28av05.in.ibm.com (d28av05.in.ibm.com [9.184.220.67]) by d28relay02.in.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id r4H3Un9J66977906 for ; Fri, 17 May 2013 09:00:49 +0530 Received: from d28av05.in.ibm.com (loopback [127.0.0.1]) by d28av05.in.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id r4H3UrlV015256 for ; Fri, 17 May 2013 13:30:53 +1000 Message-ID: <5195A457.9050402@linux.vnet.ibm.com> Date: Fri, 17 May 2013 11:30:31 +0800 From: Wenchao Xia MIME-Version: 1.0 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> In-Reply-To: <20130516081740.6c7ee91c@redhat.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit 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: Luiz Capitulino Cc: kwolf@redhat.com, phrdina@redhat.com, Stefan Hajnoczi , qemu-devel@nongnu.org, armbru@redhat.com, pbonzini@redhat.com 于 2013-5-16 20:17, Luiz Capitulino 写道: > On Thu, 16 May 2013 10:22:09 +0800 > Wenchao Xia wrote: > >> 于 2013-5-15 20:28, Luiz Capitulino 写道: >>> On Wed, 15 May 2013 10:10:37 +0800 >>> Wenchao Xia wrote: >>> >>>> 于 2013-5-6 21:22, Luiz Capitulino 写道: >>>>> On Mon, 06 May 2013 10:09:43 +0800 >>>>> Wenchao Xia wrote: >>>>> >>>>>> 于 2013-5-3 10:51, Wenchao Xia 写道: >>>>>>> 于 2013-5-2 20:02, Luiz Capitulino 写道: >>>>>>>> On Thu, 02 May 2013 10:05:08 +0800 >>>>>>>> Wenchao Xia wrote: >>>>>>>> >>>>>>>>> 于 2013-4-30 3:05, Luiz Capitulino 写道: >>>>>>>>>> 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 for >>>>>>>>>>> explicitly passing mon instead of relying on cur_mon. >>>>>>>>>> >>>>>>>>>> where are they being mixed? >>>>>>>>>> >>>>>>>>> bdrv_snapshot_dump() used a global variable "cur_mon" inside, >>>>>>>>> instead >>>>>>>>> of let caller pass in a explicit montior* "mon", I guess that is 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 than one >>>>>>> human monitor console, and then we may require a data structure to 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 your comment, >>>>> the code does support multiple monitors. >>>>> >>>> Hi Luiz, >>>> Sorry to ask again, do you think method above is OK now, waiting 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 parameter, >> 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. -- Best Regards Wenchao Xia