From mboxrd@z Thu Jan  1 00:00:00 1970
Received: from eggs.gnu.org ([208.118.235.92]:44497)
	by lists.gnu.org with esmtp (Exim 4.71)
	(envelope-from <kraxel@redhat.com>) id 1UhCkE-0007SY-GE
	for qemu-devel@nongnu.org; Tue, 28 May 2013 01:46:55 -0400
Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71)
	(envelope-from <kraxel@redhat.com>) id 1UhCkA-0008La-4F
	for qemu-devel@nongnu.org; Tue, 28 May 2013 01:46:50 -0400
Message-ID: <51A444B4.3020006@redhat.com>
Date: Tue, 28 May 2013 07:46:28 +0200
From: Gerd Hoffmann <kraxel@redhat.com>
MIME-Version: 1.0
References: <1369363654-7063-1-git-send-email-lig.fnst@cn.fujitsu.com>
	<51A323B4.2000101@redhat.com>
	<1369701066.19028.53.camel@liguang.fnst.cn.fujitsu.com>
In-Reply-To: <1369701066.19028.53.camel@liguang.fnst.cn.fujitsu.com>
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: quoted-printable
Subject: Re: [Qemu-devel] [PATCH 0/4] debugcon: fix some bugs when
	DEBUG_DEBUGCON
List-Id: <qemu-devel.nongnu.org>
List-Unsubscribe: <https://lists.nongnu.org/mailman/options/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=unsubscribe>
List-Archive: <http://lists.nongnu.org/archive/html/qemu-devel>
List-Post: <mailto:qemu-devel@nongnu.org>
List-Help: <mailto:qemu-devel-request@nongnu.org?subject=help>
List-Subscribe: <https://lists.nongnu.org/mailman/listinfo/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=subscribe>
To: li guang <lig.fnst@cn.fujitsu.com>
Cc: qemu-trivial@nongnu.org, Paolo Bonzini <pbonzini@redhat.com>, Anthony Liguori <aliguori@us.ibm.com>, qemu-devel@nongnu.org, =?UTF-8?B?QW5kcmVhcyBGw6RyYmVy?= <afaerber@suse.de>

On 05/28/13 02:31, li guang wrote:
> =E5=9C=A8 2013-05-27=E4=B8=80=E7=9A=84 11:13 +0200=EF=BC=8CGerd Hoffman=
n=E5=86=99=E9=81=93=EF=BC=9A
>> On 05/24/13 04:47, liguang wrote:
>>> when enable DEBUG_DEBUGCON, there are some message
>>> printing bugs, so fix them.
>>
>> I'd suggest to either simply remove the debug printfs or turn them int=
o
>> tracepoints.
>>
>=20
> sorry, why we simply remove debug message printing?
> it's un-useful at all?

It's a case-by-case thing.

Debug messages logging guest activity like port access tend to be useful
for trouble-shooting.  They should be turned into tracepoints, so they
can be toggled at runtime and integrate nicely with tracing tools.

Sometimes debug messages are just leftovers and don't serve a real
purpose (any more).  Then it is best to simply remove them.

In the debugcon case I'd tend to simply remove them given how trivial
the device is.  But if you prefer making them tracepoints I'm ok with tha=
t.

cheers,
  Gerd