[PATCH 00/12] Introduce CONFIG_SLUB_TINY and deprecate SLOB

[Vlastimil Babka]

Hi,

this continues the discussion from [1]. Reasons to remove SLOB are
outlined there and no-one has objected so far. The last patch of this
series therefore deprecates CONFIG_SLOB and updates all the defconfigs
using CONFIG_SLOB=y in the tree.

There is a k210 board with 8MB RAM where switching to SLUB caused issues
[2] and the lkp bot wasn't also happy about code bloat [3]. To address
both, this series introduces CONFIG_SLUB_TINY to perform some rather
low-hanging fruit modifications to SLUB to reduce its memory overhead.
This seems to have been successful at least in the k210 case [4]. I
consider this as an acceptable tradeoff for getting rid of SLOB.

The series is also available in git:
https://git.kernel.org/pub/scm/linux/kernel/git/vbabka/linux.git/log/?h=slub-tiny-v1r2

[1] https://lore.kernel.org/all/b35c3f82-f67b-2103-7d82-7a7ba7521439@suse.cz/
[2] https://lore.kernel.org/all/a5bba3ca-da19-293c-c01b-a28291533466@opensource.wdc.com/
[3] https://lore.kernel.org/all/Y25E9cJbhDAKi1vd@99bb1221be19/
[4] https://lore.kernel.org/all/6a1883c4-4c3f-545a-90e8-2cd805bcf4ae@opensource.wdc.com/

Vlastimil Babka (12):
  mm, slab: ignore hardened usercopy parameters when disabled
  mm, slub: add CONFIG_SLUB_TINY
  mm, slub: disable SYSFS support with CONFIG_SLUB_TINY
  mm, slub: retain no free slabs on partial list with CONFIG_SLUB_TINY
  mm, slub: lower the default slub_max_order with CONFIG_SLUB_TINY
  mm, slub: don't create kmalloc-rcl caches with CONFIG_SLUB_TINY
  mm, slab: ignore SLAB_RECLAIM_ACCOUNT with CONFIG_SLUB_TINY
  mm, slub: refactor free debug processing
  mm, slub: split out allocations from pre/post hooks
  mm, slub: remove percpu slabs with CONFIG_SLUB_TINY
  mm, slub: don't aggressively inline with CONFIG_SLUB_TINY
  mm, slob: rename CONFIG_SLOB to CONFIG_SLOB_DEPRECATED

 arch/arm/configs/clps711x_defconfig           |   3 +-
 arch/arm/configs/collie_defconfig             |   3 +-
 arch/arm/configs/multi_v4t_defconfig          |   3 +-
 arch/arm/configs/omap1_defconfig              |   3 +-
 arch/arm/configs/pxa_defconfig                |   3 +-
 arch/arm/configs/tct_hammer_defconfig         |   3 +-
 arch/arm/configs/xcep_defconfig               |   3 +-
 arch/openrisc/configs/or1ksim_defconfig       |   3 +-
 arch/openrisc/configs/simple_smp_defconfig    |   3 +-
 arch/riscv/configs/nommu_k210_defconfig       |   3 +-
 .../riscv/configs/nommu_k210_sdcard_defconfig |   3 +-
 arch/riscv/configs/nommu_virt_defconfig       |   3 +-
 arch/sh/configs/rsk7201_defconfig             |   3 +-
 arch/sh/configs/rsk7203_defconfig             |   3 +-
 arch/sh/configs/se7206_defconfig              |   3 +-
 arch/sh/configs/shmin_defconfig               |   3 +-
 arch/sh/configs/shx3_defconfig                |   3 +-
 include/linux/slab.h                          |   8 +
 include/linux/slub_def.h                      |   6 +-
 kernel/configs/tiny.config                    |   5 +-
 mm/Kconfig                                    |  38 +-
 mm/Kconfig.debug                              |   2 +-
 mm/slab_common.c                              |  16 +-
 mm/slub.c                                     | 415 ++++++++++++------
 24 files changed, 377 insertions(+), 164 deletions(-)

-- 
2.38.1