2010-01-20 12:52:36

by Christoph Egger

[permalink] [raw]
Subject: Obsolete config in kernel build system (XFS_TRACE)

Hi all!

As part of the VAMOS[0] research project at the University of
Erlangen we're checking referential integrity between kernel KConfig
options and in-code Conditional blocks.

Git commit 0b1b213fcf3a8486ada99a2bab84ab8c6f51b264 by
Christoph Hellwig removed all References to CONFIG_XFS_TRACE, which is
unreferenced from KConfig side from the linux source code so there's
only a small bit of it left in KBuild. Mayee remove it as well?

./fs/xfs/Makefile:95
+++>

xfs-$(CONFIG_XFS_TRACE) += xfs_btree_trace.o

<+++

Please keep me informed of this patch getting confirmed /
merged so we can keep track of it.

Regards

Christoph Egger


2010-01-20 12:58:25

by Robert P. J. Day

[permalink] [raw]
Subject: Re: Obsolete config in kernel build system (XFS_TRACE)

On Wed, 20 Jan 2010, Christoph Egger wrote:

> Hi all!
>
> As part of the VAMOS[0] research project at the University of
> Erlangen we're checking referential integrity between kernel KConfig
> options and in-code Conditional blocks.
>
> Git commit 0b1b213fcf3a8486ada99a2bab84ab8c6f51b264 by
> Christoph Hellwig removed all References to CONFIG_XFS_TRACE, which is
> unreferenced from KConfig side from the linux source code so there's
> only a small bit of it left in KBuild. Mayee remove it as well?
>
> ./fs/xfs/Makefile:95
> +++>
>
> xfs-$(CONFIG_XFS_TRACE) += xfs_btree_trace.o
>
> <+++

if the reference is being removed from the Makefile, wouldn't it
also make sense to delete the corresponding source file as well?

rday
--

========================================================================
Robert P. J. Day Waterloo, Ontario, CANADA

Linux Consulting, Training and Kernel Pedantry.

Web page: http://crashcourse.ca
Twitter: http://twitter.com/rpjday
========================================================================

2010-01-20 22:46:57

by Dave Chinner

[permalink] [raw]
Subject: Re: Obsolete config in kernel build system (XFS_TRACE)

On Wed, Jan 20, 2010 at 01:52:49PM +0100, Christoph Egger wrote:
> Hi all!
>
> As part of the VAMOS[0] research project at the University of
> Erlangen we're checking referential integrity between kernel KConfig
> options and in-code Conditional blocks.
>
> Git commit 0b1b213fcf3a8486ada99a2bab84ab8c6f51b264 by
> Christoph Hellwig removed all References to CONFIG_XFS_TRACE, which is
> unreferenced from KConfig side from the linux source code so there's
> only a small bit of it left in KBuild. Mayee remove it as well?
>
> ./fs/xfs/Makefile:95
> +++>
>
> xfs-$(CONFIG_XFS_TRACE) += xfs_btree_trace.o
>
> <+++
>
> Please keep me informed of this patch getting confirmed /
> merged so we can keep track of it.

Christoph's conversion to use the kernel trace infrastructure is
a work in progress. It's no small task - he's converted around 220
trace points points so far.

However, the btree tracing code has not been converted yet. IIRC
this is because the kernel trace code didn't have the required
infrastructure at the time of initial conversion. Hence the old code
has not yet been completely removed because the conversion is not
yet complete. It will go away when the conversion is completed.

Cheers,

Dave.
--
Dave Chinner
[email protected]

2010-01-21 12:19:12

by Christoph Hellwig

[permalink] [raw]
Subject: Re: Obsolete config in kernel build system (XFS_TRACE)

On Thu, Jan 21, 2010 at 09:46:26AM +1100, Dave Chinner wrote:
> Christoph's conversion to use the kernel trace infrastructure is
> a work in progress. It's no small task - he's converted around 220
> trace points points so far.
>
> However, the btree tracing code has not been converted yet. IIRC
> this is because the kernel trace code didn't have the required
> infrastructure at the time of initial conversion. Hence the old code
> has not yet been completely removed because the conversion is not
> yet complete. It will go away when the conversion is completed.

The btree ones are rather difficult because it will require attaching
difference events to a single tracepoint and filter on which one
we want, so it may take a bit of time.

The existing xfs_btree_trace.c won't be much use for that and if we
really need it we can look at it in git history.

Christoph, can you send a properly signed off patch to kill
xfs_btree_trace.c and and the #ifdef XFS_BTREE_TRACE code in
xfs_btree_trace.h?