[0/3] mm: sparse: remove __section_nr() function

Message

권오훈 July 2, 2021, 9:41 a.m. UTC

This series contains cleanups to remove __section_nr().

When CONFIG_SPARSEMEM_EXTREME is enabled, __section_nr() could be
costly since it iterates all section roots to check if the given
mem_section is in its range.

On the other hand, __nr_to_section which converts section_nr to
mem_section can be done in O(1).

The only users of __section_nr() was section_mark_present() and
find_memory_block().

PATCH 1 & 2 changes both functions to use section_nr instead of
mem_section.
PATCH 3 finally removes __section_nr() function.

More details can be found in each changelogs.

Ohhoon Kwon (3):
  mm: sparse: pass section_nr to section_mark_present
  mm: sparse: pass section_nr to find_memory_block
  mm: sparse: remove __section_nr() function

 .../platforms/pseries/hotplug-memory.c        |  4 +--
 drivers/base/memory.c                         |  4 +--
 include/linux/memory.h                        |  2 +-
 include/linux/mmzone.h                        |  1 -
 mm/sparse.c                                   | 35 +++----------------
 5 files changed, 9 insertions(+), 37 deletions(-)

Comments

Mike Rapoport July 2, 2021, 12:58 p.m. UTC | #1

On Fri, Jul 02, 2021 at 06:41:29PM +0900, Ohhoon Kwon wrote:
> This series contains cleanups to remove __section_nr().
> 
> When CONFIG_SPARSEMEM_EXTREME is enabled, __section_nr() could be
> costly since it iterates all section roots to check if the given
> mem_section is in its range.
> 
> On the other hand, __nr_to_section which converts section_nr to
> mem_section can be done in O(1).
> 
> The only users of __section_nr() was section_mark_present() and
> find_memory_block().
> 
> PATCH 1 & 2 changes both functions to use section_nr instead of
> mem_section.
> PATCH 3 finally removes __section_nr() function.
> 
> More details can be found in each changelogs.
> 
> Ohhoon Kwon (3):
>   mm: sparse: pass section_nr to section_mark_present
>   mm: sparse: pass section_nr to find_memory_block
>   mm: sparse: remove __section_nr() function
> 
>  .../platforms/pseries/hotplug-memory.c        |  4 +--
>  drivers/base/memory.c                         |  4 +--
>  include/linux/memory.h                        |  2 +-
>  include/linux/mmzone.h                        |  1 -
>  mm/sparse.c                                   | 35 +++----------------
>  5 files changed, 9 insertions(+), 37 deletions(-)
> 
> -- 
> 2.17.1
 
For the series:

Acked-by: Mike Rapoport <[e-mail]>