Re: [Qemu-devel] qxl: pthread_yield on QXL_IO_NOTIFY_OOM

[Jan Kiszka]

On 2011-09-20 16:48, Gerd Hoffmann wrote:
> On 09/20/11 16:27, Jan Kiszka wrote:
>> Hi Gerd,
>>
>> can you (or anyone familiar with those bits) comment on pthread_yield()
>> in ioport_write() of hw/qxl.c?  Which threads are supposed to run this
>> way?
> 
> spice server thread.
> 
>> Can't this relation be expressed explicitly?
> 
> The thread is created by libspice-server, so we don't have a handle for it.

And also no communication channel to kick?

> 
>> If not, can we use a
>> sleep here (how long?)?
> 
> Good question.  I'm tempted to just rip it out and run qxl_spice_oom() 
> unconditionally.  The yield thing is best effort only anyway, there is 
> no guarantee that the spice server thread actually gets scheduled and 
> puts some stuff into the release ring.

And the issue with sleeping is that we stall the vcpu. So just reporting
oom is likely better.

Thanks,
Jan

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