Messages in this thread | | | Date | Wed, 13 Aug 2008 11:18:50 -0700 | From | Greg KH <> | Subject | Re: [PATCH] Intel Management Engine Interface |
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On Wed, Aug 13, 2008 at 08:16:02AM +0100, Marcin Obara wrote: > 2008/8/13 Greg KH <greg@kroah.com>: > > On Mon, Aug 11, 2008 at 09:23:01PM +0200, Marcin Obara wrote: > >> +/* IOCTL commands */ > >> +#define IOCTL_HECI_GET_VERSION \ > >> + _IOWR('H' , 0x0, struct heci_message_data) > > > > This can easily be a sysfs file, why not do that instead? > > > sysfs file would require additional file handle used by every userspace client.
So, is that really a great overhead?
> GET_VERSION is called frequently
Why? Shouldn't it only be called once?
>, and sysfs file would create extra overhead.
Have you measured it?
> With ioctl - only one file handle is used, and userspace client logic > is simpler.
But the kernel is messier and we are trying to not add any more ioctls to it. Especially for trivial things like the version number of the hardware device.
> Normal flow looks like: > > open > ioctl(GET_VERSION)
Great, do an additional open/read/close here for the version, I think you will find it pretty trivial to do :)
thanks,
greg k-h
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