[PATCH 2/6] xf86drmMode: separate drmModeAtomicCommit() and drmModeAtomicCleanup()

[Hyungwon Hwang]

Hi Pekka,

On Fri, 21 Aug 2015 09:42:26 +0300
Pekka Paalanen <ppaalanen at gmail.com> wrote:

> On Fri, 21 Aug 2015 13:54:49 +0900
> Hyungwon Hwang <human.hwang at samsung.com> wrote:
> 
> > Hi Emil,
> > 
> > On Thu, 20 Aug 2015 17:17:27 +0100
> > Emil Velikov <emil.l.velikov at gmail.com> wrote:
> > 
> > > Hi Hyungwon,
> > > 
> > > On 19 August 2015 at 01:58, Hyungwon Hwang
> > > <human.hwang at samsung.com> wrote:
> > > > This patch seprates the code, which sorts proprty sets and
> > > > eliminates duplicate properties, from drmModeAtomicCommit(). Now
> > > > drmModeAtomicCleanup() has to do the job before calling
> > > > drmModeAtomicCommit(), and drmModeAtomicCommit() just converts
> > > > the cleaned request to IOCTL argument.
> > > >
> > > Afaict the commit message should say why we want this, rather than
> > > rewording what the patch does.
> > > 
> > > I'm not sure about the atomic status for wayland and others but
> > > this commit might cause issues there. Additionally, with this
> > > patch we'll send a lot of useless information to the kernel if
> > > one omits drmModeAtomicCleanup(). The kernel will likely discard
> > > it but still this doesn't seem like a good idea imho.
> > 
> > Yes. I agree that this change burdens the userspace application to
> > use API correctly. In my case, for modetest, the function of
> > cleaning up the request is needed, so I thought that this
> > separation would be needed. Overall, I agree with you. So I will
> > drop this patch, and find another way which is specific for
> > modetest.
> 
> Hi,
> 
> why do you need that, exactly?

To make the buffer for plane, I needed to figure out the width and the
height which the user set which are in the request, but not applied to
the kernel yet. To get the value from the request, I thought cleaning
the request before I try to getting the value from the request was
needed because the user could set the different values for the same
property.

> 
> 
> Thanks,
> pq