diff options
| author | Vlastimil Babka <vbabka@suse.cz> | 2022-11-23 17:41:16 +0300 |
|---|---|---|
| committer | Vlastimil Babka <vbabka@suse.cz> | 2022-12-01 02:14:00 +0300 |
| commit | dc19745ad0e46c1a069540973e376cff0130443c (patch) | |
| tree | cb3ca90fe7da95536f8e613d58bca34b9f9b7a41 /mm/Kconfig | |
| parent | 617666521385ba1a07f9388bc80d24941104e412 (diff) | |
| parent | 149b6fa228eda1d191abc440af7162264d716d90 (diff) | |
| download | linux-dc19745ad0e46c1a069540973e376cff0130443c.tar.xz | |
Merge branch 'slub-tiny-v1r6' into slab/for-next
Merge my series [1] to deprecate the SLOB allocator.
- Renames CONFIG_SLOB to CONFIG_SLOB_DEPRECATED with deprecation notice.
- The recommended replacement is CONFIG_SLUB, optionally with the new
CONFIG_SLUB_TINY tweaks for systems with 16MB or less RAM.
- Use cases that stopped working with CONFIG_SLUB_TINY instead of SLOB
should be reported to linux-mm@kvack.org and slab maintainers,
otherwise SLOB will be removed in few cycles.
[1] https://lore.kernel.org/all/20221121171202.22080-1-vbabka@suse.cz/
Diffstat (limited to 'mm/Kconfig')
| -rw-r--r-- | mm/Kconfig | 38 |
1 files changed, 32 insertions, 6 deletions
diff --git a/mm/Kconfig b/mm/Kconfig index 57e1d8c5b505..623d95659ff9 100644 --- a/mm/Kconfig +++ b/mm/Kconfig @@ -219,17 +219,43 @@ config SLUB and has enhanced diagnostics. SLUB is the default choice for a slab allocator. -config SLOB +config SLOB_DEPRECATED depends on EXPERT - bool "SLOB (Simple Allocator)" + bool "SLOB (Simple Allocator - DEPRECATED)" depends on !PREEMPT_RT help + Deprecated and scheduled for removal in a few cycles. SLUB + recommended as replacement. CONFIG_SLUB_TINY can be considered + on systems with 16MB or less RAM. + + If you need SLOB to stay, please contact linux-mm@kvack.org and + people listed in the SLAB ALLOCATOR section of MAINTAINERS file, + with your use case. + SLOB replaces the stock allocator with a drastically simpler allocator. SLOB is generally more space efficient but does not perform as well on large systems. endchoice +config SLOB + bool + default y + depends on SLOB_DEPRECATED + +config SLUB_TINY + bool "Configure SLUB for minimal memory footprint" + depends on SLUB && EXPERT + select SLAB_MERGE_DEFAULT + help + Configures the SLUB allocator in a way to achieve minimal memory + footprint, sacrificing scalability, debugging and other features. + This is intended only for the smallest system that had used the + SLOB allocator and is not recommended for systems with more than + 16MB RAM. + + If unsure, say N. + config SLAB_MERGE_DEFAULT bool "Allow slab caches to be merged" default y @@ -247,7 +273,7 @@ config SLAB_MERGE_DEFAULT config SLAB_FREELIST_RANDOM bool "Randomize slab freelist" - depends on SLAB || SLUB + depends on SLAB || (SLUB && !SLUB_TINY) help Randomizes the freelist order used on creating new pages. This security feature reduces the predictability of the kernel slab @@ -255,7 +281,7 @@ config SLAB_FREELIST_RANDOM config SLAB_FREELIST_HARDENED bool "Harden slab freelist metadata" - depends on SLAB || SLUB + depends on SLAB || (SLUB && !SLUB_TINY) help Many kernel heap attacks try to target slab cache metadata and other infrastructure. This options makes minor performance @@ -267,7 +293,7 @@ config SLAB_FREELIST_HARDENED config SLUB_STATS default n bool "Enable SLUB performance statistics" - depends on SLUB && SYSFS + depends on SLUB && SYSFS && !SLUB_TINY help SLUB statistics are useful to debug SLUBs allocation behavior in order find ways to optimize the allocator. This should never be @@ -279,7 +305,7 @@ config SLUB_STATS config SLUB_CPU_PARTIAL default y - depends on SLUB && SMP + depends on SLUB && SMP && !SLUB_TINY bool "SLUB per cpu partial cache" help Per cpu partial caches accelerate objects allocation and freeing |