diff options
Diffstat (limited to 'arch/arm64/Kconfig')
| -rw-r--r-- | arch/arm64/Kconfig | 52 |
1 files changed, 24 insertions, 28 deletions
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index 3f5bf55050e8..b1201d25a8a4 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -95,6 +95,7 @@ config ARM64 select ARCH_SUPPORTS_INT128 if CC_HAS_INT128 select ARCH_SUPPORTS_NUMA_BALANCING select ARCH_SUPPORTS_PAGE_TABLE_CHECK + select ARCH_SUPPORTS_PER_VMA_LOCK select ARCH_WANT_COMPAT_IPC_PARSE_VERSION if COMPAT select ARCH_WANT_DEFAULT_BPF_JIT select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT @@ -1505,39 +1506,34 @@ config XEN # include/linux/mmzone.h requires the following to be true: # -# MAX_ORDER - 1 + PAGE_SHIFT <= SECTION_SIZE_BITS +# MAX_ORDER + PAGE_SHIFT <= SECTION_SIZE_BITS # -# so the maximum value of MAX_ORDER is SECTION_SIZE_BITS + 1 - PAGE_SHIFT: +# so the maximum value of MAX_ORDER is SECTION_SIZE_BITS - PAGE_SHIFT: # # | SECTION_SIZE_BITS | PAGE_SHIFT | max MAX_ORDER | default MAX_ORDER | # ----+-------------------+--------------+-----------------+--------------------+ -# 4K | 27 | 12 | 16 | 11 | -# 16K | 27 | 14 | 14 | 12 | -# 64K | 29 | 16 | 14 | 14 | +# 4K | 27 | 12 | 15 | 10 | +# 16K | 27 | 14 | 13 | 11 | +# 64K | 29 | 16 | 13 | 13 | config ARCH_FORCE_MAX_ORDER - int "Maximum zone order" if ARM64_4K_PAGES || ARM64_16K_PAGES - default "14" if ARM64_64K_PAGES - range 12 14 if ARM64_16K_PAGES - default "12" if ARM64_16K_PAGES - range 11 16 if ARM64_4K_PAGES - default "11" - help - The kernel memory allocator divides physically contiguous memory - blocks into "zones", where each zone is a power of two number of - pages. This option selects the largest power of two that the kernel - keeps in the memory allocator. If you need to allocate very large - blocks of physically contiguous memory, then you may need to - increase this value. - - This config option is actually maximum order plus one. For example, - a value of 11 means that the largest free memory block is 2^10 pages. - - We make sure that we can allocate up to a HugePage size for each configuration. - Hence we have : - MAX_ORDER = (PMD_SHIFT - PAGE_SHIFT) + 1 => PAGE_SHIFT - 2 - - However for 4K, we choose a higher default value, 11 as opposed to 10, giving us - 4M allocations matching the default size used by generic code. + int "Order of maximal physically contiguous allocations" if EXPERT && (ARM64_4K_PAGES || ARM64_16K_PAGES) + default "13" if ARM64_64K_PAGES + default "11" if ARM64_16K_PAGES + default "10" + help + The kernel page allocator limits the size of maximal physically + contiguous allocations. The limit is called MAX_ORDER and it + defines the maximal power of two of number of pages that can be + allocated as a single contiguous block. This option allows + overriding the default setting when ability to allocate very + large blocks of physically contiguous memory is required. + + The maximal size of allocation cannot exceed the size of the + section, so the value of MAX_ORDER should satisfy + + MAX_ORDER + PAGE_SHIFT <= SECTION_SIZE_BITS + + Don't change if unsure. config UNMAP_KERNEL_AT_EL0 bool "Unmap kernel when running in userspace (aka \"KAISER\")" if EXPERT |