Re: [Qemu-devel] [RFC PATCH V4 0/4] Introduce COLO-compare

[Jason Wang <jasowang@redhat.com>]

On 2016年05月31日 11:54, Zhang Chen wrote:
>
>
> On 05/30/2016 11:19 AM, Jason Wang wrote:
>>
>>
>> On 2016年05月25日 20:50, Zhang Chen wrote:
>>> COLO-compare is a part of COLO project. It is used
>>> to compare the network package to help COLO decide
>>> whether to do checkpoint.
>>>
>>> the full version in this github:
>>> https://github.com/zhangckid/qemu/tree/colo-v2.7-proxy-mode-compare-with-colo-base-may25 
>>>
>>>
>>>
>>> v4:
>>>   p4:
>>>      - add some comments
>>>      - fix some trace-events
>>>      - fix tcp compare error
>>>   p3:
>>>      - add rcu_read_lock().
>>>      - fix trace name
>>>      - fix jason's other comments
>>>      - rebase some Dave's branch function
>>>   p2:
>>>      - colo_compare_connection() change g_queue_push_head() to
>>>      - g_queue_push_tail() match to sorted order.
>>>      - remove QemuMutex conn_list_lock
>>
>> Looks like conn_list lock is still there. I still prefer to do all 
>> thing in the comparing thread. Have you tried Fam's suggestion to use 
>> g_main_context_push_thread_default()? If it does not work, does it 
>> work simply by replacing all:
>>
>> g_source_attach(x, NULL);
>>
>> with
>>
>> g_souce_attach(x, g_main_context_get_thread_default());
>>
>> after call g_main_context_push_thread_default()?
>>
>> Thanks
>
> I have tried fam's suggestion it does not work.
>
> so I tried what you suggestion like that:
>
> static void *colo_compare_thread(void *opaque)
> {
>     CompareState *s = opaque;
>     GSource *source;
>     GMainContext *worker_context;
>
>     source = g_source_new(&source_funcs, sizeof(DemoSource));
>     worker_context = g_main_context_new ();
>
>     g_source_attach(source, g_main_context_get_thread_default());
>     g_source_set_callback(source, NULL, NULL, NULL);
>     g_main_context_push_thread_default (worker_context);
>     qemu_chr_add_handlers(s->chr_pri_in, compare_chr_can_read,
>                           compare_pri_chr_in, NULL, s);
>     qemu_chr_add_handlers(s->chr_sec_in, compare_chr_can_read,
>                           compare_sec_chr_in, NULL, s);
>     g_main_context_pop_thread_default (worker_context);

g_source_attach() should be done after g_main_context_push_thread_default()

>
>
> but it does not work too. Do you mean like this?

Not exactly the same, but should be worth to try also. My suggestion is 
to replace all g_source_attach(src, NULL) in qemu source (especially the 
ones in qemu-char.c) with g_source_attach(src, 
g_main_context_get_thread_default()). (Maybe not that easy, but better 
to have a try).

You may refer 
https://developer.gnome.org/glib/unstable/glib-The-Main-Event-Loop.html 
for more docs on this. I believe there should have some solutions on this.

>
> Thanks
> Zhang Chen
>
>>>      - remove pkt->s
>>>      - move data structure to colo-base.h
>>>      - add colo-base.c reuse codes for filter-rewriter
>>>      - add some filter-rewriter needs struct
>>>      - depends on previous SocketReadState patch
>>>   p1:
>>>      - except move qemu_chr_add_handlers()
>>>        to colo thread
>>>      - remove class_finalize
>>>      - remove secondary arp codes
>>>      - depends on previous SocketReadState patch
>>>
>>> v3:
>>>    - rebase colo-compare to colo-frame v2.7
>>>    - fix most of Dave's comments
>>>      (except RCU)
>>>    - add TCP,UDP,ICMP and other packet comparison
>>>    - add trace-event
>>>    - add some comments
>>>    - other bug fix
>>>    - add RFC index
>>>    - add usage in patch 1/4
>>>
>>> v2:
>>>    - add jhash.h
>>>
>>> v1:
>>>    - initial patch
>>>
>>>
>>> Zhang Chen (4):
>>>    colo-compare: introduce colo compare initialization
>>>    colo-compare: track connection and enqueue packet
>>>    colo-compare: introduce packet comparison thread
>>>    colo-compare: add TCP,UDP,ICMP packet comparison
>>>
>>>   include/qemu/jhash.h |  61 +++++
>>>   net/Makefile.objs    |   2 +
>>>   net/colo-base.c      | 183 +++++++++++++
>>>   net/colo-base.h      |  92 +++++++
>>>   net/colo-compare.c   | 745 
>>> +++++++++++++++++++++++++++++++++++++++++++++++++++
>>>   qemu-options.hx      |  34 +++
>>>   trace-events         |  11 +
>>>   vl.c                 |   3 +-
>>>   8 files changed, 1130 insertions(+), 1 deletion(-)
>>>   create mode 100644 include/qemu/jhash.h
>>>   create mode 100644 net/colo-base.c
>>>   create mode 100644 net/colo-base.h
>>>   create mode 100644 net/colo-compare.c
>>>
>>
>>
>>
>> .
>>
>