[RFC PATCH v2 0/4] remove duplicate ifdefs

[Shrikanth Hegde <sshegde@linux.ibm.com>]

When going through the code observed a case in scheduler,
where #ifdef CONFIG_SMP was used to inside an #ifdef CONFIG_SMP.
That didn't make sense since first one is good enough and second
one is a duplicate.

This could improve code readability. No functional change is intended.

Since this might be present in other code areas wrote a very basic
python script which helps in finding these cases. It doesn't handle any
complicated #defines or space separated "# if". At some places the
log collected had to be manually corrected due to space separated ifdefs.
Thats why its not a treewide change.
There might be an opportunity for other files as well.

Logic is very simple. If there is #ifdef or #if or #ifndef add that
variable to list. Upon every subsequent #ifdef or #if or #ifndef
check if the same variable is in the list. If yes flag
an error. Verification was done manually later checking for any #undef
or any error due to script. These were the ones that flagged out and
made sense after going through code.

More details about how the logs were collected and the script used for
processing the logs are mentioned in v1 cover letter.

v2->v1:
split the fs change into two patches as suggested by Chandan Babu R.
v1: https://lore.kernel.org/all/20240118080326.13137-1-sshegde@linux.ibm.com/

Shrikanth Hegde (4):
  sched: remove duplicate ifdefs
  xfs: remove duplicate ifdefs
  ntfs: remove duplicate ifdefs
  arch/powerpc: remove duplicate ifdefs

 arch/powerpc/include/asm/paca.h           | 4 ----
 arch/powerpc/kernel/asm-offsets.c         | 2 --
 arch/powerpc/platforms/powermac/feature.c | 2 --
 arch/powerpc/xmon/xmon.c                  | 2 --
 fs/ntfs/inode.c                           | 2 --
 fs/xfs/xfs_sysfs.c                        | 4 ----
 kernel/sched/core.c                       | 4 +---
 kernel/sched/fair.c                       | 2 --
 8 files changed, 1 insertion(+), 21 deletions(-)

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2.39.3