From: Arnd Bergmann <[email protected]>
These four architectures define the same Kconfig symbols for configuring
the page size. Move the logic into a common place where it can be shared
with all other architectures.
Signed-off-by: Arnd Bergmann <[email protected]>
---
Changes from v1:
- improve Kconfig help texts
- fix Hexagon Kconfig
arch/Kconfig | 92 ++++++++++++++++++++++++++++++-
arch/hexagon/Kconfig | 24 ++------
arch/hexagon/include/asm/page.h | 6 +-
arch/loongarch/Kconfig | 21 ++-----
arch/loongarch/include/asm/page.h | 10 +---
arch/mips/Kconfig | 58 ++-----------------
arch/mips/include/asm/page.h | 16 +-----
arch/sh/include/asm/page.h | 13 +----
arch/sh/mm/Kconfig | 42 ++++----------
9 files changed, 121 insertions(+), 161 deletions(-)
diff --git a/arch/Kconfig b/arch/Kconfig
index a5af0edd3eb8..c63034e092d0 100644
--- a/arch/Kconfig
+++ b/arch/Kconfig
@@ -1078,17 +1078,105 @@ config HAVE_ARCH_COMPAT_MMAP_BASES
and vice-versa 32-bit applications to call 64-bit mmap().
Required for applications doing different bitness syscalls.
+config HAVE_PAGE_SIZE_4KB
+ bool
+
+config HAVE_PAGE_SIZE_8KB
+ bool
+
+config HAVE_PAGE_SIZE_16KB
+ bool
+
+config HAVE_PAGE_SIZE_32KB
+ bool
+
+config HAVE_PAGE_SIZE_64KB
+ bool
+
+config HAVE_PAGE_SIZE_256KB
+ bool
+
+choice
+ prompt "MMU page size"
+
+config PAGE_SIZE_4KB
+ bool "4KiB pages"
+ depends on HAVE_PAGE_SIZE_4KB
+ help
+ This option select the standard 4KiB Linux page size and the only
+ available option on many architectures. Using 4KiB page size will
+ minimize memory consumption and is therefore recommended for low
+ memory systems.
+ Some software that is written for x86 systems makes incorrect
+ assumptions about the page size and only runs on 4KiB pages.
+
+config PAGE_SIZE_8KB
+ bool "8KiB pages"
+ depends on HAVE_PAGE_SIZE_8KB
+ help
+ This option is the only supported page size on a few older
+ processors, and can be slightly faster than 4KiB pages.
+
+config PAGE_SIZE_16KB
+ bool "16KiB pages"
+ depends on HAVE_PAGE_SIZE_16KB
+ help
+ This option is usually a good compromise between memory
+ consumption and performance for typical desktop and server
+ workloads, often saving a level of page table lookups compared
+ to 4KB pages as well as reducing TLB pressure and overhead of
+ per-page operations in the kernel at the expense of a larger
+ page cache.
+
+config PAGE_SIZE_32KB
+ bool "32KiB pages"
+ depends on HAVE_PAGE_SIZE_32KB
+ Using 32KiB page size will result in slightly higher performance
+ kernel at the price of higher memory consumption compared to
+ 16KiB pages. This option is available only on cnMIPS cores.
+ Note that you will need a suitable Linux distribution to
+ support this.
+
+config PAGE_SIZE_64KB
+ bool "64KiB pages"
+ depends on HAVE_PAGE_SIZE_64KB
+ Using 64KiB page size will result in slightly higher performance
+ kernel at the price of much higher memory consumption compared to
+ 4KiB or 16KiB pages.
+ This is not suitable for general-purpose workloads but the
+ better performance may be worth the cost for certain types of
+ supercomputing or database applications that work mostly with
+ large in-memory data rather than small files.
+
+config PAGE_SIZE_256KB
+ bool "256KiB pages"
+ depends on HAVE_PAGE_SIZE_256KB
+ help
+ 256KiB pages have little practical value due to their extreme
+ memory usage. The kernel will only be able to run applications
+ that have been compiled with '-zmax-page-size' set to 256KiB
+ (the default is 64KiB or 4KiB on most architectures).
+
+endchoice
+
config PAGE_SIZE_LESS_THAN_64KB
def_bool y
- depends on !ARM64_64K_PAGES
depends on !PAGE_SIZE_64KB
- depends on !PARISC_PAGE_SIZE_64KB
depends on PAGE_SIZE_LESS_THAN_256KB
config PAGE_SIZE_LESS_THAN_256KB
def_bool y
depends on !PAGE_SIZE_256KB
+config PAGE_SHIFT
+ int
+ default 12 if PAGE_SIZE_4KB
+ default 13 if PAGE_SIZE_8KB
+ default 14 if PAGE_SIZE_16KB
+ default 15 if PAGE_SIZE_32KB
+ default 16 if PAGE_SIZE_64KB
+ default 18 if PAGE_SIZE_256KB
+
# This allows to use a set of generic functions to determine mmap base
# address by giving priority to top-down scheme only if the process
# is not in legacy mode (compat task, unlimited stack size or
diff --git a/arch/hexagon/Kconfig b/arch/hexagon/Kconfig
index a880ee067d2e..1414052e7d6b 100644
--- a/arch/hexagon/Kconfig
+++ b/arch/hexagon/Kconfig
@@ -8,6 +8,10 @@ config HEXAGON
select ARCH_HAS_SYNC_DMA_FOR_DEVICE
select ARCH_NO_PREEMPT
select DMA_GLOBAL_POOL
+ select HAVE_PAGE_SIZE_4KB
+ select HAVE_PAGE_SIZE_16KB
+ select HAVE_PAGE_SIZE_64KB
+ select HAVE_PAGE_SIZE_256KB
# Other pending projects/to-do items.
# select HAVE_REGS_AND_STACK_ACCESS_API
# select HAVE_HW_BREAKPOINT if PERF_EVENTS
@@ -120,26 +124,6 @@ config NR_CPUS
This is purely to save memory - each supported CPU adds
approximately eight kilobytes to the kernel image.
-choice
- prompt "Kernel page size"
- default PAGE_SIZE_4KB
- help
- Changes the default page size; use with caution.
-
-config PAGE_SIZE_4KB
- bool "4KB"
-
-config PAGE_SIZE_16KB
- bool "16KB"
-
-config PAGE_SIZE_64KB
- bool "64KB"
-
-config PAGE_SIZE_256KB
- bool "256KB"
-
-endchoice
-
source "kernel/Kconfig.hz"
endmenu
diff --git a/arch/hexagon/include/asm/page.h b/arch/hexagon/include/asm/page.h
index 32394b7e752e..8a6af57274c2 100644
--- a/arch/hexagon/include/asm/page.h
+++ b/arch/hexagon/include/asm/page.h
@@ -13,27 +13,22 @@
/* This is probably not the most graceful way to handle this. */
#ifdef CONFIG_PAGE_SIZE_4KB
-#define PAGE_SHIFT 12
#define HEXAGON_L1_PTE_SIZE __HVM_PDE_S_4KB
#endif
#ifdef CONFIG_PAGE_SIZE_16KB
-#define PAGE_SHIFT 14
#define HEXAGON_L1_PTE_SIZE __HVM_PDE_S_16KB
#endif
#ifdef CONFIG_PAGE_SIZE_64KB
-#define PAGE_SHIFT 16
#define HEXAGON_L1_PTE_SIZE __HVM_PDE_S_64KB
#endif
#ifdef CONFIG_PAGE_SIZE_256KB
-#define PAGE_SHIFT 18
#define HEXAGON_L1_PTE_SIZE __HVM_PDE_S_256KB
#endif
#ifdef CONFIG_PAGE_SIZE_1MB
-#define PAGE_SHIFT 20
#define HEXAGON_L1_PTE_SIZE __HVM_PDE_S_1MB
#endif
@@ -50,6 +45,7 @@
#define HVM_HUGEPAGE_SIZE 0x5
#endif
+#define PAGE_SHIFT CONFIG_PAGE_SHIFT
#define PAGE_SIZE (1UL << PAGE_SHIFT)
#define PAGE_MASK (~((1 << PAGE_SHIFT) - 1))
diff --git a/arch/loongarch/Kconfig b/arch/loongarch/Kconfig
index 929f68926b34..b274784c2e26 100644
--- a/arch/loongarch/Kconfig
+++ b/arch/loongarch/Kconfig
@@ -227,15 +227,6 @@ config MACH_LOONGSON64
config FIX_EARLYCON_MEM
def_bool y
-config PAGE_SIZE_4KB
- bool
-
-config PAGE_SIZE_16KB
- bool
-
-config PAGE_SIZE_64KB
- bool
-
config PGTABLE_2LEVEL
bool
@@ -288,7 +279,7 @@ choice
config 4KB_3LEVEL
bool "4KB with 3 levels"
- select PAGE_SIZE_4KB
+ select HAVE_PAGE_SIZE_4KB
select PGTABLE_3LEVEL
help
This option selects 4KB page size with 3 level page tables, which
@@ -296,7 +287,7 @@ config 4KB_3LEVEL
config 4KB_4LEVEL
bool "4KB with 4 levels"
- select PAGE_SIZE_4KB
+ select HAVE_PAGE_SIZE_4KB
select PGTABLE_4LEVEL
help
This option selects 4KB page size with 4 level page tables, which
@@ -304,7 +295,7 @@ config 4KB_4LEVEL
config 16KB_2LEVEL
bool "16KB with 2 levels"
- select PAGE_SIZE_16KB
+ select HAVE_PAGE_SIZE_16KB
select PGTABLE_2LEVEL
help
This option selects 16KB page size with 2 level page tables, which
@@ -312,7 +303,7 @@ config 16KB_2LEVEL
config 16KB_3LEVEL
bool "16KB with 3 levels"
- select PAGE_SIZE_16KB
+ select HAVE_PAGE_SIZE_16KB
select PGTABLE_3LEVEL
help
This option selects 16KB page size with 3 level page tables, which
@@ -320,7 +311,7 @@ config 16KB_3LEVEL
config 64KB_2LEVEL
bool "64KB with 2 levels"
- select PAGE_SIZE_64KB
+ select HAVE_PAGE_SIZE_64KB
select PGTABLE_2LEVEL
help
This option selects 64KB page size with 2 level page tables, which
@@ -328,7 +319,7 @@ config 64KB_2LEVEL
config 64KB_3LEVEL
bool "64KB with 3 levels"
- select PAGE_SIZE_64KB
+ select HAVE_PAGE_SIZE_64KB
select PGTABLE_3LEVEL
help
This option selects 64KB page size with 3 level page tables, which
diff --git a/arch/loongarch/include/asm/page.h b/arch/loongarch/include/asm/page.h
index 63f137ce82a4..afb6fa16b826 100644
--- a/arch/loongarch/include/asm/page.h
+++ b/arch/loongarch/include/asm/page.h
@@ -11,15 +11,7 @@
/*
* PAGE_SHIFT determines the page size
*/
-#ifdef CONFIG_PAGE_SIZE_4KB
-#define PAGE_SHIFT 12
-#endif
-#ifdef CONFIG_PAGE_SIZE_16KB
-#define PAGE_SHIFT 14
-#endif
-#ifdef CONFIG_PAGE_SIZE_64KB
-#define PAGE_SHIFT 16
-#endif
+#define PAGE_SHIFT CONFIG_PAGE_SHIFT
#define PAGE_SIZE (_AC(1, UL) << PAGE_SHIFT)
#define PAGE_MASK (~(PAGE_SIZE - 1))
diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig
index 797ae590ebdb..24bac93affee 100644
--- a/arch/mips/Kconfig
+++ b/arch/mips/Kconfig
@@ -81,6 +81,9 @@ config MIPS
select HAVE_LD_DEAD_CODE_DATA_ELIMINATION
select HAVE_MOD_ARCH_SPECIFIC
select HAVE_NMI
+ select HAVE_PAGE_SIZE_4KB if !CPU_LOONGSON2EF && !CPU_LOONGSON64
+ select HAVE_PAGE_SIZE_16KB if !CPU_R3000
+ select HAVE_PAGE_SIZE_64KB if !CPU_R3000
select HAVE_PERF_EVENTS
select HAVE_PERF_REGS
select HAVE_PERF_USER_STACK_DUMP
@@ -1608,6 +1611,8 @@ config CPU_CAVIUM_OCTEON
depends on SYS_HAS_CPU_CAVIUM_OCTEON
select CPU_HAS_PREFETCH
select CPU_SUPPORTS_64BIT_KERNEL
+ select HAVE_PAGE_SIZE_8KB if !MIPS_VA_BITS_48
+ select HAVE_PAGE_SIZE_32KB if !MIPS_VA_BITS_48
select WEAK_ORDERING
select CPU_SUPPORTS_HIGHMEM
select CPU_SUPPORTS_HUGEPAGES
@@ -2029,59 +2034,6 @@ config ZBOOT_LOAD_ADDRESS
This is only used if non-zero.
-choice
- prompt "Kernel page size"
- default PAGE_SIZE_4KB
-
-config PAGE_SIZE_4KB
- bool "4kB"
- depends on !CPU_LOONGSON2EF && !CPU_LOONGSON64
- help
- This option select the standard 4kB Linux page size. On some
- R3000-family processors this is the only available page size. Using
- 4kB page size will minimize memory consumption and is therefore
- recommended for low memory systems.
-
-config PAGE_SIZE_8KB
- bool "8kB"
- depends on CPU_CAVIUM_OCTEON
- depends on !MIPS_VA_BITS_48
- help
- Using 8kB page size will result in higher performance kernel at
- the price of higher memory consumption. This option is available
- only on cnMIPS processors. Note that you will need a suitable Linux
- distribution to support this.
-
-config PAGE_SIZE_16KB
- bool "16kB"
- depends on !CPU_R3000
- help
- Using 16kB page size will result in higher performance kernel at
- the price of higher memory consumption. This option is available on
- all non-R3000 family processors. Note that you will need a suitable
- Linux distribution to support this.
-
-config PAGE_SIZE_32KB
- bool "32kB"
- depends on CPU_CAVIUM_OCTEON
- depends on !MIPS_VA_BITS_48
- help
- Using 32kB page size will result in higher performance kernel at
- the price of higher memory consumption. This option is available
- only on cnMIPS cores. Note that you will need a suitable Linux
- distribution to support this.
-
-config PAGE_SIZE_64KB
- bool "64kB"
- depends on !CPU_R3000
- help
- Using 64kB page size will result in higher performance kernel at
- the price of higher memory consumption. This option is available on
- all non-R3000 family processor. Not that at the time of this
- writing this option is still high experimental.
-
-endchoice
-
config ARCH_FORCE_MAX_ORDER
int "Maximum zone order"
default "13" if MIPS_HUGE_TLB_SUPPORT && PAGE_SIZE_64KB
diff --git a/arch/mips/include/asm/page.h b/arch/mips/include/asm/page.h
index ef9585d96f6b..4609cb0326cf 100644
--- a/arch/mips/include/asm/page.h
+++ b/arch/mips/include/asm/page.h
@@ -17,21 +17,7 @@
/*
* PAGE_SHIFT determines the page size
*/
-#ifdef CONFIG_PAGE_SIZE_4KB
-#define PAGE_SHIFT 12
-#endif
-#ifdef CONFIG_PAGE_SIZE_8KB
-#define PAGE_SHIFT 13
-#endif
-#ifdef CONFIG_PAGE_SIZE_16KB
-#define PAGE_SHIFT 14
-#endif
-#ifdef CONFIG_PAGE_SIZE_32KB
-#define PAGE_SHIFT 15
-#endif
-#ifdef CONFIG_PAGE_SIZE_64KB
-#define PAGE_SHIFT 16
-#endif
+#define PAGE_SHIFT CONFIG_PAGE_SHIFT
#define PAGE_SIZE (_AC(1,UL) << PAGE_SHIFT)
#define PAGE_MASK (~((1 << PAGE_SHIFT) - 1))
diff --git a/arch/sh/include/asm/page.h b/arch/sh/include/asm/page.h
index 62f4b9edcb98..f780b467e75d 100644
--- a/arch/sh/include/asm/page.h
+++ b/arch/sh/include/asm/page.h
@@ -9,18 +9,7 @@
#include <linux/const.h>
/* PAGE_SHIFT determines the page size */
-#if defined(CONFIG_PAGE_SIZE_4KB)
-# define PAGE_SHIFT 12
-#elif defined(CONFIG_PAGE_SIZE_8KB)
-# define PAGE_SHIFT 13
-#elif defined(CONFIG_PAGE_SIZE_16KB)
-# define PAGE_SHIFT 14
-#elif defined(CONFIG_PAGE_SIZE_64KB)
-# define PAGE_SHIFT 16
-#else
-# error "Bogus kernel page size?"
-#endif
-
+#define PAGE_SHIFT CONFIG_PAGE_SHIFT
#define PAGE_SIZE (_AC(1, UL) << PAGE_SHIFT)
#define PAGE_MASK (~(PAGE_SIZE-1))
#define PTE_MASK PAGE_MASK
diff --git a/arch/sh/mm/Kconfig b/arch/sh/mm/Kconfig
index 455311d9a5e9..f32a1963ff0c 100644
--- a/arch/sh/mm/Kconfig
+++ b/arch/sh/mm/Kconfig
@@ -4,6 +4,9 @@ menu "Memory management options"
config MMU
bool "Support for memory management hardware"
depends on !CPU_SH2
+ select HAVE_PAGE_SIZE_4KB
+ select HAVE_PAGE_SIZE_8KB if X2TLB
+ select HAVE_PAGE_SIZE_64KB if CPU_SH4
default y
help
Some SH processors (such as SH-2/SH-2A) lack an MMU. In order to
@@ -13,6 +16,15 @@ config MMU
turning this off will boot the kernel on these machines with the
MMU implicitly switched off.
+config NOMMU
+ def_bool !MMU
+ select HAVE_PAGE_SIZE_4KB
+ select HAVE_PAGE_SIZE_8KB
+ select HAVE_PAGE_SIZE_16KB
+ select HAVE_PAGE_SIZE_64KB
+ help
+ On MMU-less systems, any of these page sizes can be selected
+
config PAGE_OFFSET
hex
default "0x80000000" if MMU
@@ -147,36 +159,6 @@ config HAVE_SRAM_POOL
bool
select GENERIC_ALLOCATOR
-choice
- prompt "Kernel page size"
- default PAGE_SIZE_4KB
-
-config PAGE_SIZE_4KB
- bool "4kB"
- help
- This is the default page size used by all SuperH CPUs.
-
-config PAGE_SIZE_8KB
- bool "8kB"
- depends on !MMU || X2TLB
- help
- This enables 8kB pages as supported by SH-X2 and later MMUs.
-
-config PAGE_SIZE_16KB
- bool "16kB"
- depends on !MMU
- help
- This enables 16kB pages on MMU-less SH systems.
-
-config PAGE_SIZE_64KB
- bool "64kB"
- depends on !MMU || CPU_SH4
- help
- This enables support for 64kB pages, possible on all SH-4
- CPUs and later.
-
-endchoice
-
choice
prompt "HugeTLB page size"
depends on HUGETLB_PAGE
--
2.39.2
On Wed, Mar 06 2024 at 15:14, Arnd Bergmann wrote:
> From: Arnd Bergmann <[email protected]>
>
> These four architectures define the same Kconfig symbols for configuring
> the page size. Move the logic into a common place where it can be shared
> with all other architectures.
>
> Signed-off-by: Arnd Bergmann <[email protected]>
Reviewed-by: Thomas Gleixner <[email protected]>
Hi Arnd,
Arnd Bergmann <[email protected]> writes:
> From: Arnd Bergmann <[email protected]>
>
> These four architectures define the same Kconfig symbols for configuring
> the page size. Move the logic into a common place where it can be shared
> with all other architectures.
>
> Signed-off-by: Arnd Bergmann <[email protected]>
> ---
> Changes from v1:
> - improve Kconfig help texts
> - fix Hexagon Kconfig
>
> arch/Kconfig | 92 ++++++++++++++++++++++++++++++-
> arch/hexagon/Kconfig | 24 ++------
> arch/hexagon/include/asm/page.h | 6 +-
> arch/loongarch/Kconfig | 21 ++-----
> arch/loongarch/include/asm/page.h | 10 +---
> arch/mips/Kconfig | 58 ++-----------------
> arch/mips/include/asm/page.h | 16 +-----
> arch/sh/include/asm/page.h | 13 +----
> arch/sh/mm/Kconfig | 42 ++++----------
> 9 files changed, 121 insertions(+), 161 deletions(-)
There's a few "help" lines missing, which breaks the build:
arch/Kconfig:1134: syntax error
arch/Kconfig:1133: invalid statement
arch/Kconfig:1134: invalid statement
arch/Kconfig:1135:warning: ignoring unsupported character '.'
arch/Kconfig:1135:warning: ignoring unsupported character '.'
arch/Kconfig:1135: invalid statement
arch/Kconfig:1136: invalid statement
arch/Kconfig:1137:warning: ignoring unsupported character '.'
arch/Kconfig:1137: invalid statement
arch/Kconfig:1143: syntax error
arch/Kconfig:1142: invalid statement
arch/Kconfig:1143: invalid statement
arch/Kconfig:1144:warning: ignoring unsupported character '.'
arch/Kconfig:1144: invalid statement
arch/Kconfig:1145: invalid statement
arch/Kconfig:1146: invalid statement
arch/Kconfig:1147: invalid statement
arch/Kconfig:1148:warning: ignoring unsupported character '.'
arch/Kconfig:1148: invalid statement
make[4]: *** [../scripts/kconfig/Makefile:85: syncconfig] Error 1
Fixup diff is:
diff --git a/arch/Kconfig b/arch/Kconfig
index 56d45a75f625..f2295fa3b48c 100644
--- a/arch/Kconfig
+++ b/arch/Kconfig
@@ -1130,6 +1130,7 @@ config PAGE_SIZE_16KB
config PAGE_SIZE_32KB
bool "32KiB pages"
depends on HAVE_PAGE_SIZE_32KB
+ help
Using 32KiB page size will result in slightly higher performance
kernel at the price of higher memory consumption compared to
16KiB pages. This option is available only on cnMIPS cores.
@@ -1139,6 +1140,7 @@ config PAGE_SIZE_32KB
config PAGE_SIZE_64KB
bool "64KiB pages"
depends on HAVE_PAGE_SIZE_64KB
+ help
Using 64KiB page size will result in slightly higher performance
kernel at the price of much higher memory consumption compared to
4KiB or 16KiB pages.
cheers