2011-06-07 08:11:21

by Denys Vlasenko

[permalink] [raw]
Subject: Re: Status of function-sections work?

On Monday 06 June 2011 03:15, Josh Triplett wrote:
> Hello,
>
> I found your work in 2010 on using function-sections and data-sections
> to eliminate unused code in the kernel. I'd like to make use of this
> work to try to build an extremely space-constrained kernel.
>
> It looks like a few of your patches made it into the kernel, but most of
> the linker script changes don't seem to have made it in. I wanted to
> find out the status of this work. Do you still have this working? Do
> you have versions of your patches for current Linux?

parisc uses ^ in some identifiers. Therefore we need something like
[A-Za-z0-9_$^]* in linker script. This wasn't working with GNU ld -
^ is not a valid char for pattern. Use of more general [!.]*
was also impossible - ! is not a valid char too.

Therefore I asked binutils people to fix this (they agreed) and
decided to wait for a fixed binutils to be released.


> Have you considered re-submitting?

Yes, I need to do this...


--
vda


2011-06-07 08:43:57

by Josh Triplett

[permalink] [raw]
Subject: Re: Status of function-sections work?

On Tue, Jun 07, 2011 at 10:11:15AM +0200, Denys Vlasenko wrote:
> On Monday 06 June 2011 03:15, Josh Triplett wrote:
> > Hello,
> >
> > I found your work in 2010 on using function-sections and data-sections
> > to eliminate unused code in the kernel. I'd like to make use of this
> > work to try to build an extremely space-constrained kernel.
> >
> > It looks like a few of your patches made it into the kernel, but most of
> > the linker script changes don't seem to have made it in. I wanted to
> > find out the status of this work. Do you still have this working? Do
> > you have versions of your patches for current Linux?
>
> parisc uses ^ in some identifiers. Therefore we need something like
> [A-Za-z0-9_$^]* in linker script. This wasn't working with GNU ld -
> ^ is not a valid char for pattern. Use of more general [!.]*
> was also impossible - ! is not a valid char too.
>
> Therefore I asked binutils people to fix this (they agreed) and
> decided to wait for a fixed binutils to be released.

Makes sense. Thanks for the explanation and status.

Do you know if the fix has gone into binutils, either in a release or
the latest snapshot from version control? If not, does a patch exist?

- Josh Triplett

2011-06-07 15:06:31

by Denys Vlasenko

[permalink] [raw]
Subject: Re: Status of function-sections work?

On Tue, Jun 7, 2011 at 10:43 AM, Josh Triplett <[email protected]> wrote:
> On Tue, Jun 07, 2011 at 10:11:15AM +0200, Denys Vlasenko wrote:
>> On Monday 06 June 2011 03:15, Josh Triplett wrote:
>> > Hello,
>> >
>> > I found your work in 2010 on using function-sections and data-sections
>> > to eliminate unused code in the kernel. ?I'd like to make use of this
>> > work to try to build an extremely space-constrained kernel.
>> >
>> > It looks like a few of your patches made it into the kernel, but most of
>> > the linker script changes don't seem to have made it in. ?I wanted to
>> > find out the status of this work. ?Do you still have this working? ?Do
>> > you have versions of your patches for current Linux?
>>
>> parisc uses ^ in some identifiers. Therefore we need something like
>> [A-Za-z0-9_$^]* in linker script. This wasn't working with GNU ld -
>> ^ is not a valid char for pattern. Use of more general [!.]*
>> was also impossible - ! is not a valid char too.
>>
>> Therefore I asked binutils people to fix this (they agreed) and
>> decided to wait for a fixed binutils to be released.
>
> Makes sense. ?Thanks for the explanation and status.
>
> Do you know if the fix has gone into binutils, either in a release or
> the latest snapshot from version control? ?If not, does a patch exist?

Yes, latest released binutils has the fix.
--
vda