[libvirt] [PATCH]lxc: improve readability of lxcContainer[Send|Waitfor]Continue

[Daniel P. Berrange]

On Mon, Oct 21, 2013 at 02:28:37PM +0100, Michal Privoznik wrote:
> On 16.10.2013 08:27, Chen Hanxiao wrote:
> > From: Chen Hanxiao <chenhanxiao at cn.fujitsu.com>
> > 
> > Currently, lxcContainer[Send|Waitfor]Continue only tell
> > us 'fd', but we had to deal with the interaction between
> > lxc_[container|controller|process].
> > This patch adds parameters to identify the caller.
> > 
> > Signed-off-by: Chen Hanxiao <chenhanxiao at cn.fujitsu.com>
> > ---
> >  src/lxc/lxc_container.c  | 16 +++++++++-------
> >  src/lxc/lxc_container.h  |  4 ++--
> >  src/lxc/lxc_controller.c |  6 +++---
> >  src/lxc/lxc_process.c    |  2 +-
> >  4 files changed, 15 insertions(+), 13 deletions(-)
> 
> I think this can be achieved even without this hack. We already can
> produce a stack trace on VIR_DEBUG() [1]. And if you don't want to keep
> only some debug messages, apply filters.

FYI, you don't even need to look at stack traces. The debug message
includes the PID - the LXC controller will have a large random PID
number, while what will become the container init process will have
PID ==1

eg

# grep Continue wait9.log 
2013-09-10 14:54:54.416+0000: 17150: debug : lxcContainerSendContinue:366 : Send continue on fd 8
2013-09-10 14:54:54.416+0000: 17150: debug : lxcContainerWaitForContinue:392 : Wait continue on fd 10
2013-09-10 14:54:54.416+0000: 1: debug : lxcContainerWaitForContinue:392 : Wait continue on fd 9
2013-09-10 14:54:54.416+0000: 1: debug : lxcContainerWaitForContinue:394 : Got continue on fd 9 1
2013-09-10 14:54:54.437+0000: 1: debug : lxcContainerSendContinue:366 : Send continue on fd 11
2013-09-10 14:54:54.437+0000: 17150: debug : lxcContainerWaitForContinue:394 : Got continue on fd 10 1
2013-09-10 14:54:54.437+0000: 17150: debug : lxcContainerSendContinue:366 : Send continue on fd 52


So I agree, this patch is not really compelling enough to add

Daniel
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