Re: [PATCH v2 01/11] dma-buf/sync_file: de-stage sync_file

From: Gustavo Padovan
Date: Wed Jan 27 2016 - 12:03:24 EST

Hi Maarten,

2016-01-27 Maarten Lankhorst <maarten.lankhorst@xxxxxxxxxxxxxxx>:

> Hey,
> Op 27-01-16 om 14:30 schreef Gustavo Padovan:
> > From: Gustavo Padovan <gustavo.padovan@xxxxxxxxxxxxxxx>
> >
> > sync_file is useful to connect one or more fences to the file. The file is
> > used by userspace to track fences.
> >
> > Signed-off-by: Gustavo Padovan <gustavo.padovan@xxxxxxxxxxxxxxx>
> >
> Is there a value in keeping the abi unchanged?
> If not, then Documentation/ioctl/botching-up-ioctls.txt is worth a read.

None from me. I'll look where we can improve the ABI.

> Looking at the patch, it seems you kept SYNC_IOC_WAIT, won't it be better to remove it, and only support waiting with polling?
> The code for polling should already work.

Sure, that makes sense for me.

> It's very unclear what format @driver_data has. I kept it for compatibility with android, but it's not clear to me how a userspace consumer would print it.
> Is there a usecase for this, or could it be removed from fence and sync_file?

I don't have any usecase for this. I'd say we remove it for now and if
someone needs this in the future we can talk about this again.