Re: Kernel thoughts of a Linux user

Gerold J. Wucherpfennig
2004-11-21T07:26:53Z

> On Thu, Nov 18, 2004 at 06:59:27PM +0100, Gerold J. Wucherpfennig wrote:
> >
> > - Make sysfs optional and enable to publish kernel <-> userspace data
> > especially the kernel's KObject data across the kernel's netlink interface
as
> > it has been summarized on www.kerneltrap.org. This will avoid the
> > deadlocks sysfs does introduce when some userspace app holds an open file
> > handle of an sysfs object (KObject) which is to be removed. An importrant
side
> > effect for embedded systems will be that the RAM overhead introduced by
sysfs
> > will vaporize.
>
> What RAM overhead? With 2.6.10-rc2 the memory footprint of sysfs has
> been drasticly shrunk.

Sorry I my kernel knowledge only consists of kerneltrap.org news :-(
I didn't knew that.

>
> What deadlocks are you referring to?
>

I don't know if it are deadlocks, please read last years article from lwn:
http://lwn.net/Articles/36850/

> And the netlink interface for hotplug events is already present in the
> latest kernel.

I don't know much about netlink. But sysfs --> libsysfs --> hal --> dbus
seems to be a lot of an overhead. Maybe create an in-kernel queue
for hardware information requests and publish the hardware information
with netlink would be a little less overhead??? Just a though...