Re: [Qemu-devel] [PATCH 08/12] Threadlet: Add aio_signal_handler threadlet API

[Stefan Hajnoczi <stefanha@gmail.com>]

On Tue, Jan 18, 2011 at 6:10 PM, Venkateswararao Jujjuri (JV)
<jvrao@linux.vnet.ibm.com> wrote:
> On 1/17/2011 11:14 PM, Stefan Hajnoczi wrote:
>> On Tue, Jan 18, 2011 at 6:46 AM, Arun R Bharadwaj
>> <arun@linux.vnet.ibm.com> wrote:
>>> * Stefan Hajnoczi <stefanha@gmail.com> [2011-01-18 06:31:34]:
>>>
>>>> On Tue, Jan 18, 2011 at 4:43 AM, Arun R Bharadwaj
>>>> <arun@linux.vnet.ibm.com> wrote:
>>>>> * Stefan Hajnoczi <stefanha@gmail.com> [2011-01-17 09:56:58]:
>>>>>
>>>>>> On Thu, Jan 13, 2011 at 12:14 PM, Arun R Bharadwaj
>>>>>> <arun@linux.vnet.ibm.com> wrote:
>>>>>>> +static void threadlet_io_completion_signal_handler(int signum)
>>>>>>> +{
>>>>>>> +    qemu_service_io();
>>>>>>> +}
>>>>>>> +
>>>>>>> +static void threadlet_register_signal_handler(void)
>>>>>>> +{
>>>>>>> +    struct sigaction act;
>>>>>>> +    sigfillset(&act.sa_mask);
>>>>>>> +    act.sa_flags = 0; /* do not restart syscalls to interrupt select() */
>>>>>>> +    act.sa_handler = threadlet_io_completion_signal_handler;
>>>>>>> +    sigaction(SIGUSR2, &act, NULL);
>>>>>>> +}
>>>>>>> +
>>>>>>> +void threadlet_init(void)
>>>>>>> +{
>>>>>>> +    threadlet_register_signal_handler();
>>>>>>> +}
>>>>>>
>>>>>> This would be the right place to create qemu-threadlet.c, instead of
>>>>>> adding the thread_init() prototype to qemu-thread.h and then including
>>>>>> that in vl.c.
>>>>>>
>>>>>> Stefan
>>>>>
>>>>> I did not follow your comment here. How can we avoid including
>>>>> threadler_init() in vl.c?
>>>>
>>>> Instead of adding threadlet_init() and related functions to
>>>> posix-aio-compat.c and adding the prototype to qemu-thread.h, why not
>>>> just create qemu-threadlet.c/qemu-threadlet.h and put these functions
>>>> there instead?
>>>>
>>>> Stefan
>>>
>>> Got it. So you mean I merge patch 8 and patch 10 into a single patch.
>>> But wouldn't this mean we are moving code and adding new API in the
>>> same patch? Anthony did not want this from what I recall. But I can do
>>> it if you feel it makes things simple.
>>
>> I don't think you need to merge the patches.  It's odd to add
>> functions to posix-aio-compat.c but put the prototype in qemu-thread.h
>> (and then include and call from vl.c).  So for these three functions
>> (threadlet_init, threadlet_register_signal_handler, and
>> threadlet_io_completion_signal_handler) only I think it makes sense to
>> move them to qemu-threadlet.[ch] straight away.
>
> So basically create the new file qemu-threadlet.[ch] with only these functions
> and move the rest of the code in patch 10(as we do now).

Exactly.

Stefan