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* identifying CONFIG variable typoes in the source tree
@ 2007-01-23 21:13 Robert P. J. Day
  2007-01-23 23:35 ` Oleg Verych
  2007-01-24  8:21 ` Geert Uytterhoeven
  0 siblings, 2 replies; 5+ messages in thread
From: Robert P. J. Day @ 2007-01-23 21:13 UTC (permalink / raw)
  To: Linux kernel mailing list


  because it's cold outside and i was bored, i put together the
following script, to be run from the top of the source tree:

======================================================B
#!/bin/sh

CV=$(grep -rh "^#.*if.* CONFIG_[A-Za-z0-9]" . | grep -v endif)
CVARS=$(echo "${CV}" | sed "s/.*\(CONFIG_[^	 =\)\*\/]*\).*/\1/" | sort -u | grep "^CONFIG_")

kcfiles=$(find . -name "Kconfig*")

for cv in ${CVARS} ; do
	# echo "cv = ${cv}"
	str=$(echo ${cv} | sed "s/^CONFIG_//")
	# echo "str = ${str}"
	grep -wq ${str} ${kcfiles} || echo ${str}
done
=======================================================

  what it does is scan the entire tree for lines of the form

...if... CONFIG_whatever...

collects all of those CONFIG variables and, one at a time, checks to
see if that variable even exists in any Kconfig file in the tree so
that it could possibly ever be set.  (i'm not guaranteeing that the
script is perfect, but it does generate some interesting results.)

  the first few lines of output:

53C700_BE_BUS
64_BIT
68328_SERIAL_UART2
...

  let's check these:

$ grep -r 53C700_BE_BUS .
./drivers/scsi/53c700.h:#ifdef CONFIG_53C700_BE_BUS

  in short, a variable that's being tested with no possibility of ever
being set in a Kconfig file.  moving on,

$ grep -rw CONFIG_64_BIT .
./include/asm-um/elf-ppc.h:#ifdef CONFIG_64_BIT
$ grep -rw 64_BIT .
$

  so CONFIG_64_BIT is similarly being tested, but it's not being set
anywhere.  i'm guessing this is a misspelling of "CONFIG_64BIT", which
*does* exist in the tree and is quite common.  next:

$ grep -r 68328_SERIAL_UART2 .
./drivers/serial/68328serial.h:#ifndef CONFIG_68328_SERIAL_UART2
./arch/m68knommu/platform/68VZ328/config.c:#ifdef CONFIG_68328_SERIAL_UART2

  again, something being tested with no possibility of it being set
anywhere.

  the script turns up 284 examples of this.

rday

^ permalink raw reply	[flat|nested] 5+ messages in thread

* Re: identifying CONFIG variable typoes in the source tree
  2007-01-23 21:13 identifying CONFIG variable typoes in the source tree Robert P. J. Day
@ 2007-01-23 23:35 ` Oleg Verych
  2007-01-24  2:02   ` Robert P. J. Day
  2007-01-24  8:21 ` Geert Uytterhoeven
  1 sibling, 1 reply; 5+ messages in thread
From: Oleg Verych @ 2007-01-23 23:35 UTC (permalink / raw)
  To: linux-kernel

On 2007-01-23, Robert P. J. Day wrote:
[]
>   what it does is scan the entire tree for lines of the form
>
> ...if... CONFIG_whatever...
>
> collects all of those CONFIG variables and, one at a time, checks to
> see if that variable even exists in any Kconfig file in the tree so
> that it could possibly ever be set.  (i'm not guaranteeing that the
> script is perfect, but it does generate some interesting results.)
>
>   the first few lines of output:
>
> 53C700_BE_BUS
> 64_BIT
> 68328_SERIAL_UART2
> ...
>
[]
>   the script turns up 284 examples of this.

Next, this script must to learn how to search whom to send this info.
And if there's nobody, just to make list of known orphans ;).

> rday

____


^ permalink raw reply	[flat|nested] 5+ messages in thread

* Re: identifying CONFIG variable typoes in the source tree
  2007-01-23 23:35 ` Oleg Verych
@ 2007-01-24  2:02   ` Robert P. J. Day
  0 siblings, 0 replies; 5+ messages in thread
From: Robert P. J. Day @ 2007-01-24  2:02 UTC (permalink / raw)
  To: Oleg Verych; +Cc: linux-kernel

[-- Attachment #1: Type: TEXT/PLAIN, Size: 1607 bytes --]


On Tue, 23 Jan 2007, Oleg Verych wrote:

> On 2007-01-23, Robert P. J. Day wrote:
> []
> >   what it does is scan the entire tree for lines of the form
> >
> > ...if... CONFIG_whatever...
> >
> > collects all of those CONFIG variables and, one at a time, checks to
> > see if that variable even exists in any Kconfig file in the tree so
> > that it could possibly ever be set.  (i'm not guaranteeing that the
> > script is perfect, but it does generate some interesting results.)
> >
> >   the first few lines of output:
> >
> > 53C700_BE_BUS
> > 64_BIT
> > 68328_SERIAL_UART2
> > ...
> >
> []
> >   the script turns up 284 examples of this.
>
> Next, this script must to learn how to search whom to send this info.
> And if there's nobody, just to make list of known orphans ;).

  i'm pretty sure that's not going to happen this evening, but i
tweaked the script just a bit so you can run it (from the top-level
directory) against any subdirectory to see what CONFIG symbols appear
to be (for lack of a better word) "orphaned."

  let's test it against, say, fs/xfs:

$ ../config_vars.sh fs/xfs
FS_POSIX_CAP
FS_POSIX_MAC
XFS_DEBUG
XFS_DMAPI
XFS_TRACE

$ grep -r FS_POSIX_CAP .
fs/xfs/xfs_cap.h:#ifdef CONFIG_FS_POSIX_CAP

$ grep -r FS_POSIX_MAC .
./fs/xfs/xfs_mac.h:#ifdef CONFIG_FS_POSIX_MAC

$ grep -r XFS_DEBUG .
./fs/xfs/xfs.h:#ifdef CONFIG_XFS_DEBUG
./fs/xfs/Makefile-linux-2.6:ifeq ($(CONFIG_XFS_DEBUG),y)

and so on.  of course, there may be good reasons for some of these
variables to be there with no corresponding Kconfig entry -- i'm just
printing them out.

rday

p.s. new script is attached.

[-- Attachment #2: Type: APPLICATION/x-sh, Size: 435 bytes --]

^ permalink raw reply	[flat|nested] 5+ messages in thread

* Re: identifying CONFIG variable typoes in the source tree
  2007-01-23 21:13 identifying CONFIG variable typoes in the source tree Robert P. J. Day
  2007-01-23 23:35 ` Oleg Verych
@ 2007-01-24  8:21 ` Geert Uytterhoeven
  2007-01-24 10:33   ` Robert P. J. Day
  1 sibling, 1 reply; 5+ messages in thread
From: Geert Uytterhoeven @ 2007-01-24  8:21 UTC (permalink / raw)
  To: Robert P. J. Day; +Cc: Linux kernel mailing list

On Tue, 23 Jan 2007, Robert P. J. Day wrote:
>   let's check these:
> 
> $ grep -r 53C700_BE_BUS .
> ./drivers/scsi/53c700.h:#ifdef CONFIG_53C700_BE_BUS

This is the core support for big endian 53c700 SCSI busses. It's needed for
various m68k machines, patch to be submitted when the m68k support is ready for
submission.

Gr{oetje,eeting}s,

						Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
							    -- Linus Torvalds

^ permalink raw reply	[flat|nested] 5+ messages in thread

* Re: identifying CONFIG variable typoes in the source tree
  2007-01-24  8:21 ` Geert Uytterhoeven
@ 2007-01-24 10:33   ` Robert P. J. Day
  0 siblings, 0 replies; 5+ messages in thread
From: Robert P. J. Day @ 2007-01-24 10:33 UTC (permalink / raw)
  To: Geert Uytterhoeven; +Cc: Linux kernel mailing list

On Wed, 24 Jan 2007, Geert Uytterhoeven wrote:

> On Tue, 23 Jan 2007, Robert P. J. Day wrote:
> >   let's check these:
> >
> > $ grep -r 53C700_BE_BUS .
> > ./drivers/scsi/53c700.h:#ifdef CONFIG_53C700_BE_BUS
>
> This is the core support for big endian 53c700 SCSI busses. It's
> needed for various m68k machines, patch to be submitted when the
> m68k support is ready for submission.
>
> Gr{oetje,eeting}s,

  just to be clear, all that script is doing is identifying variables
of the form "CONFIG_fubar" that are being tested in *some*
preprocessor directive somewhere in the tree, but for which there is
apparently no corresponding entry in a Kconfig file anywhere that
could cause that variable to be configured.

  naturally, as geert suggests, this might represent a feature that's
in progress so it's clearly not a mistake.  but it's a good way to
trap potential problems, as in finding "GALILLEO_GT64240_ETH" which,
superficially, would seem like an obvious typo no matter what:

$ grep -r GALILLEO_GT64240_ETH .
./arch/mips/momentum/ocelot_g/prom.c:#ifdef CONFIG_GALILLEO_GT64240_ETH
./arch/mips/momentum/ocelot_g/prom.c:#ifdef CONFIG_GALILLEO_GT64240_ETH
./arch/mips/momentum/ocelot_g/setup.c:#ifdef CONFIG_GALILLEO_GT64240_ETH
./arch/mips/momentum/ocelot_g/setup.c:#ifdef CONFIG_GALILLEO_GT64240_ETH
$

as well as what is *obviously* dead code:

$ grep -rw CONFIG_KERNELD .
./sound/core/timer.c:#ifdef CONFIG_KERNELD
$ grep -rw KERNELD .
./net/core/dev.c: *             Bjorn Ekwall    :       Added KERNELD hack.

  the script isn't perfect -- it will generate false positives if the
variable is being set elsewhere -- perhaps hardcoded in the file or
defined in a Makefile.  but if you're curious, just run it against
your favourite subdirectory and see what comes up.

rday


^ permalink raw reply	[flat|nested] 5+ messages in thread

end of thread, other threads:[~2007-01-24 10:33 UTC | newest]

Thread overview: 5+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2007-01-23 21:13 identifying CONFIG variable typoes in the source tree Robert P. J. Day
2007-01-23 23:35 ` Oleg Verych
2007-01-24  2:02   ` Robert P. J. Day
2007-01-24  8:21 ` Geert Uytterhoeven
2007-01-24 10:33   ` Robert P. J. Day

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