[PATCH xserver] Pass ClientPtr to FlushCallback

Michel Dänzer michel at daenzer.net
Wed Aug 3 00:51:19 UTC 2016

On 03.08.2016 09:40, Eric Anholt wrote:
> Michel Dänzer <michel at daenzer.net> writes:
>> From: Michel Dänzer <michel.daenzer at amd.com>
>> This change has two effects:
>> 1. Only calls FlushCallbacks when we're actually flushing data to a
>>    client. The unnecessary FlushCallback calls could cause significant
>>    performance degradation with compositing, which is significantly
>>    reduced even without any driver changes.
>> 2. By passing the ClientPtr to FlushCallbacks, drivers can completely
>>    eliminate unnecessary flushing of GPU commands by keeping track of
>>    whether we're flushing any XDamageNotify events to the client for
>>    which the corresponding rendering commands haven't been flushed to
>>    the GPU yet.
>> Signed-off-by: Michel Dänzer <michel.daenzer at amd.com>
>> ---
>> See https://lists.freedesktop.org/archives/amd-gfx/2016-August/000977.html
>> for an example of how to take advantage of this change to eliminate
>> unnecessary GPU flushes.
> Note: Mesa's DRI2 is (supposed to be) doing XSync() during glXWaitX() to
> ensure that the server has processed the client's X requests and flushed
> its batchbuffers, so that the kernel serializes the batchbuffer from X
> before the next rendering by Mesa.  I think your xf86-video-ati patches
> will break that.

Can you elaborate how? I honestly can't imagine.

Earthling Michel Dänzer               |               http://www.amd.com
Libre software enthusiast             |             Mesa and X developer

-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 181 bytes
Desc: OpenPGP digital signature
URL: <https://lists.x.org/archives/xorg-devel/attachments/20160803/bc78b159/attachment.sig>

More information about the xorg-devel mailing list