unnecessary polls of cdrom block device from udisks daemon

[Aaron Lu]

Hi,

On Fri, Apr 06, 2012 at 12:07:06PM -0400, David Zeuthen wrote:
> Hey,
> 
> On Fri, Apr 6, 2012 at 5:15 AM, Aaron Lu <aaron.lu at amd.com> wrote:
> > Hi,
> >
> > I'm doing some development on Linux scsi cdrom driver(sr module)
> > recently and found that the udisks daemon will periodically open the
> > ODD block device /dev/sr0. I guess the reason is to check events, since
> > on block open, the check_events function will be called.
> >
> > But since the udev will also enable in kernel polling by change the
> > kernel parameter /sys/module/block/parameters/events_dfl_poll_msecs to 2
> > seconds, so the polls done by udisks daemon by a open system call for
> > the scsi cdrom block device should be unnecessary.
> 
> Maybe you are just using an old version of udisks? As of udisks 1.0.3
> (released mid 2011), we no longer poll if the kernel does, this is the
> commit
> 
> http://cgit.freedesktop.org/udisks/commit/?h=udisks1&id=2d0272eb3be71f6ee3f52c55a3d608764b675fb0
> 
> For udisks2, we never poll, we assume the kernel is always polling.
> 

Thanks for the information.

I just test again, and didn't see any more udisks polls...
I have no idea what happened the last time, I indeed see a lot of opens
from udisks. I'm using udisks-1.0.4-3.fc16.x86_64.

Anyway, from your description, this is already fixed and if it ever
happens again to me, it should be a bug :-)

Thanks,
Aaron