On 04/28/2012 05:49 PM, Shevek wrote:
> On Sat, 2012-04-28 at 17:34 +0800, Liu Yuan wrote:
>> On 04/28/2012 05:22 PM, Shevek wrote:
>>
>>>>> - if (join_finished)
>>>>> + if (join_finished || is_master(&cevent->sender))
>>> I believe this patch does NOT work:
>>>
>>> 1) is_master returns -1 for not-master, 0 means the given node is
>>> master, so this is apparently a misuse of is_master.
>>>
>>> However, even worse:
>>>
>>> 2) If we never got a join response, then line 388:
>>> 388 if (!cevent->blocked && cpg_node_equal(&cevent->sender,
>>> &this_node)) {
>>> never triggered, therefore we have never set join_finished, and
>>> nr_cpg_nodes is always 0 (look for every place where it got set), so
>>> is_master() is always 0.
>>>
>>> So, by inspection, this patch can never work, for both reasons.
>>>
>>
>>
>> Oh, yes. Thanks for pointing it out.
>>
>> But what if set set
>>
>> if (join_finished || (is_master(&cevent->sender >= 0)))
>> done = __corosync_dispatch_one(cevent);
>> else
>> done = !cevent->blocked;
>>
>> Then, the master will be called for sure, and would give other nodes a
>> join response.
>
> As I said before under (2), is_master() will always return 0, since the
> only assignments to nr_cpg_nodes are within __corosync_dispatch_one()
> (which has never yet been called) or when first_node == 1 (which never
> happened).
>
> So this new patch is still invalid.
>
confchg event will be broadcast to all the nodes.
for our case, if is_master() returns >=0, it means the very node *is*
the master, then will call into __corosync_dispatch_one[1], where then
it will call into send_message(response).
so your assumption for (2) isn't valid.
[1]
if (join_finished || (is_master(&cevent->sender >= 0)))
done = __corosync_dispatch_one(cevent);
Thanks,
Yuan
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