Porting kref to a 2.4 kernel (2.4.20 or greater)

Porting kref to a 2.4 kernel (2.4.20 or greater)

[Hareesh Nagarajan]

Hi,

What stumbling blocks do you think I would encounter if I wanted to port 
kref to a 2.4.xx kernel? Is kref tightly coupled with the kernel object 
infrastructure found in the 2.6.xx kernel?

Many thanks!

Hareesh
-= Engineering Intern =-
cs.uic.edu/~hnagaraj

Re: Porting kref to a 2.4 kernel (2.4.20 or greater)

[Greg KH]

On Wed, Jun 15, 2005 at 10:20:04AM -0700, Hareesh Nagarajan wrote:
> Hi,
> 
> What stumbling blocks do you think I would encounter if I wanted to port 
> kref to a 2.4.xx kernel? Is kref tightly coupled with the kernel object 
> infrastructure found in the 2.6.xx kernel?

Have you looked at the kref code to see if there is any such coupling?
Can you describe any problems you are having doing the uncoupling?

What do you want this in the 2.4 kernel for?  You know that no new
features are being accepted for that tree, right?

thanks,

greg k-h

Re: Porting kref to a 2.4 kernel (2.4.20 or greater)

[Hareesh Nagarajan]

Greg KH wrote:
> On Wed, Jun 15, 2005 at 10:20:04AM -0700, Hareesh Nagarajan wrote:
> 
>>What stumbling blocks do you think I would encounter if I wanted to port 
>>kref to a 2.4.xx kernel? Is kref tightly coupled with the kernel object 
>>infrastructure found in the 2.6.xx kernel?
> 
> Have you looked at the kref code to see if there is any such coupling?

Not really. Kref seems pretty light and loosely coupled with the 2.6 
kernel. There just appears to be a C file (and a .h of course).

> Can you describe any problems you are having doing the uncoupling?

I'm having problems porting the KObject and Work Queue infrastructure to 
the 2.4 kernel. Any ideas if anyone has tried this port?

> What do you want this in the 2.4 kernel for?  

I need to port RelayFS into a 2.4 kernel.

> You know that no new
> features are being accepted for that tree, right?

Yes, I am aware of that :(

Thank you very much!

Hareesh
-= Engineering Intern =-
cs.uic.edu/~hnagaraj

Re: Porting kref to a 2.4 kernel (2.4.20 or greater)

[Hareesh Nagarajan]

Correction:
(Appears with a *)

Greg KH wrote:
> On Wed, Jun 15, 2005 at 10:20:04AM -0700, Hareesh Nagarajan wrote:
> 
>>What stumbling blocks do you think I would encounter if I wanted to port 
>>kref to a 2.4.xx kernel? Is kref tightly coupled with the kernel object 
>>infrastructure found in the 2.6.xx kernel?
> 
> Have you looked at the kref code to see if there is any such coupling?

Not really. Kref seems pretty light and loosely coupled with the 2.6
kernel. There just appears to be a C file (and a .h of course).

> Can you describe any problems you are having doing the uncoupling?

I'm having problems porting the KObject* and Work Queue infrastructure 
to the 2.4 kernel. Any ideas if anyone has tried this port?

(Correction: * => I meant KThread)

Sorry about that!

Hareesh
-= Engineering Intern =-
cs.uic.edu/~hnagaraj

Re: Porting kref to a 2.4 kernel (2.4.20 or greater)

[Dipankar Sarma]

On Wed, Jun 15, 2005 at 03:47:51PM -0700, Hareesh Nagarajan wrote:
> Correction:
> (Appears with a *)
> 
> Greg KH wrote:
> >On Wed, Jun 15, 2005 at 10:20:04AM -0700, Hareesh Nagarajan wrote:
> >
> >>What stumbling blocks do you think I would encounter if I wanted to port 
> >>kref to a 2.4.xx kernel? Is kref tightly coupled with the kernel object 
> >>infrastructure found in the 2.6.xx kernel?
> >
> >Have you looked at the kref code to see if there is any such coupling?
> 
> >Can you describe any problems you are having doing the uncoupling?
> 
> I'm having problems porting the KObject* and Work Queue infrastructure 
> to the 2.4 kernel. Any ideas if anyone has tried this port?
> 
> (Correction: * => I meant KThread)

There were a number of backports of 2.6 workqueue stuff without
kthread (before they were introduced for cpu hotplug) floating
around in mailing list. You can probably google for them.
Aren't they sufficient or does google want to do CPU hotplug ? :)

Thanks
Dipankar

Re: Porting kref to a 2.4 kernel (2.4.20 or greater)

[Hareesh Nagarajan]

Dipankar Sarma wrote:
> On Wed, Jun 15, 2005 at 03:47:51PM -0700, Hareesh Nagarajan wrote:
> 
>>Correction:
>>(Appears with a *)
>>
>>Greg KH wrote:
>>
>>>On Wed, Jun 15, 2005 at 10:20:04AM -0700, Hareesh Nagarajan wrote:
>>>
>>>
>>>>What stumbling blocks do you think I would encounter if I wanted to port 
>>>>kref to a 2.4.xx kernel? Is kref tightly coupled with the kernel object 
>>>>infrastructure found in the 2.6.xx kernel?
>>>
>>>Have you looked at the kref code to see if there is any such coupling?
>>
>>>Can you describe any problems you are having doing the uncoupling?
>>
>>I'm having problems porting the KObject* and Work Queue infrastructure 
>>to the 2.4 kernel. Any ideas if anyone has tried this port?
>>
>>(Correction: * => I meant KThread)
> 
> 
> There were a number of backports of 2.6 workqueue stuff without
> kthread (before they were introduced for cpu hotplug) floating
> around in mailing list. You can probably google for them.

I will do that!

> Aren't they sufficient or does google want to do CPU hotplug ? :)

I was thinking of porting the RelayFS patches (from 2.6.11-mm2) to the 
2.4 kernel. RelayFS seems to use the work queue infrastructure.

And AFAIK, Google doesn't seem to be too interested in hotplugging :)

Thanks Dipankar!

Hareesh

Re: Porting kref to a 2.4 kernel (2.4.20 or greater)

[Greg KH]

On Wed, Jun 15, 2005 at 03:47:51PM -0700, Hareesh Nagarajan wrote:
> Correction:
> (Appears with a *)
> 
> Greg KH wrote:
> >On Wed, Jun 15, 2005 at 10:20:04AM -0700, Hareesh Nagarajan wrote:
> >
> >>What stumbling blocks do you think I would encounter if I wanted to port 
> >>kref to a 2.4.xx kernel? Is kref tightly coupled with the kernel object 
> >>infrastructure found in the 2.6.xx kernel?
> >
> >Have you looked at the kref code to see if there is any such coupling?
> 
> Not really. Kref seems pretty light and loosely coupled with the 2.6
> kernel. There just appears to be a C file (and a .h of course).

Exactly, that code should have no problems working in 2.4.

Good luck,

greg k-h