The patch titled
Subject: arm: remove CONFIG_ARCH_HAS_HOLES_MEMORYMODEL
has been added to the -mm tree. Its filename is
arm-remove-config_arch_has_holes_memorymodel.patch
This patch should soon appear at
https://ozlabs.org/~akpm/mmots/broken-out/arm-remove-config_arch_has_holes_memorymodel.patch
and later at
https://ozlabs.org/~akpm/mmotm/broken-out/arm-remove-config_arch_has_holes_memorymodel.patch
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*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***
The -mm tree is included into linux-next and is updated
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------------------------------------------------------
From: Mike Rapoport <rppt@xxxxxxxxxxxxx>
Subject: arm: remove CONFIG_ARCH_HAS_HOLES_MEMORYMODEL
ARM is the only architecture that defines CONFIG_ARCH_HAS_HOLES_MEMORYMODEL
which in turn enables memmap_valid_within() function that is intended to
verify existence of struct page associated with a pfn when there are holes
in the memory map.
However, the ARCH_HAS_HOLES_MEMORYMODEL also enables HAVE_ARCH_PFN_VALID
and arch-specific pfn_valid() implementation that also deals with the holes
in the memory map.
The only two users of memmap_valid_within() call this function after
a call to pfn_valid() so the memmap_valid_within() check becomes redundant.
Remove CONFIG_ARCH_HAS_HOLES_MEMORYMODEL and memmap_valid_within() and rely
entirely on ARM's implementation of pfn_valid() that is now enabled
unconditionally.
Link: https://lkml.kernel.org/r/20201101170454.9567-9-rppt@xxxxxxxxxx
Signed-off-by: Mike Rapoport <rppt@xxxxxxxxxxxxx>
Cc: Alexey Dobriyan <adobriyan@xxxxxxxxx>
Cc: Catalin Marinas <catalin.marinas@xxxxxxx>
Cc: Geert Uytterhoeven <geert@xxxxxxxxxxxxxx>
Cc: Greg Ungerer <gerg@xxxxxxxxxxxxxx>
Cc: John Paul Adrian Glaubitz <glaubitz@xxxxxxxxxxxxxxxxxxx>
Cc: Jonathan Corbet <corbet@xxxxxxx>
Cc: Matt Turner <mattst88@xxxxxxxxx>
Cc: Meelis Roos <mroos@xxxxxxxx>
Cc: Michael Schmitz <schmitzmic@xxxxxxxxx>
Cc: Russell King <linux@xxxxxxxxxxxxxxx>
Cc: Tony Luck <tony.luck@xxxxxxxxx>
Cc: Vineet Gupta <vgupta@xxxxxxxxxxxx>
Cc: Will Deacon <will@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
Documentation/vm/memory-model.rst | 3 --
arch/arm/Kconfig | 8 +------
arch/arm/mach-bcm/Kconfig | 1
arch/arm/mach-davinci/Kconfig | 1
arch/arm/mach-exynos/Kconfig | 1
arch/arm/mach-highbank/Kconfig | 1
arch/arm/mach-omap2/Kconfig | 1
arch/arm/mach-s5pv210/Kconfig | 1
arch/arm/mach-tango/Kconfig | 1
fs/proc/kcore.c | 2 -
include/linux/mmzone.h | 31 ----------------------------
mm/mmzone.c | 14 ------------
mm/vmstat.c | 4 ---
13 files changed, 3 insertions(+), 66 deletions(-)
--- a/arch/arm/Kconfig~arm-remove-config_arch_has_holes_memorymodel
+++ a/arch/arm/Kconfig
@@ -25,7 +25,7 @@ config ARM
select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
select ARCH_HAVE_CUSTOM_GPIO_H
select ARCH_HAS_GCOV_PROFILE_ALL
- select ARCH_KEEP_MEMBLOCK if HAVE_ARCH_PFN_VALID || KEXEC
+ select ARCH_KEEP_MEMBLOCK
select ARCH_MIGHT_HAVE_PC_PARPORT
select ARCH_NO_SG_CHAIN if !ARM_HAS_SG_CHAIN
select ARCH_OPTIONAL_KERNEL_RWX if ARCH_HAS_STRICT_KERNEL_RWX
@@ -519,7 +519,6 @@ config ARCH_S3C24XX
config ARCH_OMAP1
bool "TI OMAP1"
depends on MMU
- select ARCH_HAS_HOLES_MEMORYMODEL
select ARCH_OMAP
select CLKDEV_LOOKUP
select CLKSRC_MMIO
@@ -1479,9 +1478,6 @@ config OABI_COMPAT
UNPREDICTABLE (in fact it can be predicted that it won't work
at all). If in doubt say N.
-config ARCH_HAS_HOLES_MEMORYMODEL
- bool
-
config ARCH_SELECT_MEMORY_MODEL
bool
@@ -1493,7 +1489,7 @@ config ARCH_SPARSEMEM_ENABLE
select SPARSEMEM_STATIC if SPARSEMEM
config HAVE_ARCH_PFN_VALID
- def_bool ARCH_HAS_HOLES_MEMORYMODEL || !SPARSEMEM
+ def_bool y
config HIGHMEM
bool "High Memory Support"
--- a/arch/arm/mach-bcm/Kconfig~arm-remove-config_arch_has_holes_memorymodel
+++ a/arch/arm/mach-bcm/Kconfig
@@ -211,7 +211,6 @@ config ARCH_BRCMSTB
select BCM7038_L1_IRQ
select BRCMSTB_L2_IRQ
select BCM7120_L2_IRQ
- select ARCH_HAS_HOLES_MEMORYMODEL
select ZONE_DMA if ARM_LPAE
select SOC_BRCMSTB
select SOC_BUS
--- a/arch/arm/mach-davinci/Kconfig~arm-remove-config_arch_has_holes_memorymodel
+++ a/arch/arm/mach-davinci/Kconfig
@@ -5,7 +5,6 @@ menuconfig ARCH_DAVINCI
depends on ARCH_MULTI_V5
select DAVINCI_TIMER
select ZONE_DMA
- select ARCH_HAS_HOLES_MEMORYMODEL
select PM_GENERIC_DOMAINS if PM
select PM_GENERIC_DOMAINS_OF if PM && OF
select REGMAP_MMIO
--- a/arch/arm/mach-exynos/Kconfig~arm-remove-config_arch_has_holes_memorymodel
+++ a/arch/arm/mach-exynos/Kconfig
@@ -8,7 +8,6 @@
menuconfig ARCH_EXYNOS
bool "Samsung Exynos"
depends on ARCH_MULTI_V7
- select ARCH_HAS_HOLES_MEMORYMODEL
select ARCH_SUPPORTS_BIG_ENDIAN
select ARM_AMBA
select ARM_GIC
--- a/arch/arm/mach-highbank/Kconfig~arm-remove-config_arch_has_holes_memorymodel
+++ a/arch/arm/mach-highbank/Kconfig
@@ -2,7 +2,6 @@
config ARCH_HIGHBANK
bool "Calxeda ECX-1000/2000 (Highbank/Midway)"
depends on ARCH_MULTI_V7
- select ARCH_HAS_HOLES_MEMORYMODEL
select ARCH_SUPPORTS_BIG_ENDIAN
select ARM_AMBA
select ARM_ERRATA_764369 if SMP
--- a/arch/arm/mach-omap2/Kconfig~arm-remove-config_arch_has_holes_memorymodel
+++ a/arch/arm/mach-omap2/Kconfig
@@ -94,7 +94,6 @@ config SOC_DRA7XX
config ARCH_OMAP2PLUS
bool
select ARCH_HAS_BANDGAP
- select ARCH_HAS_HOLES_MEMORYMODEL
select ARCH_HAS_RESET_CONTROLLER
select ARCH_OMAP
select CLKSRC_MMIO
--- a/arch/arm/mach-s5pv210/Kconfig~arm-remove-config_arch_has_holes_memorymodel
+++ a/arch/arm/mach-s5pv210/Kconfig
@@ -8,7 +8,6 @@
config ARCH_S5PV210
bool "Samsung S5PV210/S5PC110"
depends on ARCH_MULTI_V7
- select ARCH_HAS_HOLES_MEMORYMODEL
select ARM_VIC
select CLKSRC_SAMSUNG_PWM
select COMMON_CLK_SAMSUNG
--- a/arch/arm/mach-tango/Kconfig~arm-remove-config_arch_has_holes_memorymodel
+++ a/arch/arm/mach-tango/Kconfig
@@ -3,7 +3,6 @@ config ARCH_TANGO
bool "Sigma Designs Tango4 (SMP87xx)"
depends on ARCH_MULTI_V7
# Cortex-A9 MPCore r3p0, PL310 r3p2
- select ARCH_HAS_HOLES_MEMORYMODEL
select ARM_ERRATA_754322
select ARM_ERRATA_764369 if SMP
select ARM_ERRATA_775420
--- a/Documentation/vm/memory-model.rst~arm-remove-config_arch_has_holes_memorymodel
+++ a/Documentation/vm/memory-model.rst
@@ -51,8 +51,7 @@ call :c:func:`free_area_init` function.
usable until the call to :c:func:`memblock_free_all` that hands all the
memory to the page allocator.
-If an architecture enables `CONFIG_ARCH_HAS_HOLES_MEMORYMODEL` option,
-it may free parts of the `mem_map` array that do not cover the
+An architecture may free parts of the `mem_map` array that do not cover the
actual physical pages. In such case, the architecture specific
:c:func:`pfn_valid` implementation should take the holes in the
`mem_map` into account.
--- a/fs/proc/kcore.c~arm-remove-config_arch_has_holes_memorymodel
+++ a/fs/proc/kcore.c
@@ -193,8 +193,6 @@ kclist_add_private(unsigned long pfn, un
return 1;
p = pfn_to_page(pfn);
- if (!memmap_valid_within(pfn, p, page_zone(p)))
- return 1;
ent = kmalloc(sizeof(*ent), GFP_KERNEL);
if (!ent)
--- a/include/linux/mmzone.h~arm-remove-config_arch_has_holes_memorymodel
+++ a/include/linux/mmzone.h
@@ -1440,37 +1440,6 @@ void sparse_init(void);
#define pfn_valid_within(pfn) (1)
#endif
-#ifdef CONFIG_ARCH_HAS_HOLES_MEMORYMODEL
-/*
- * pfn_valid() is meant to be able to tell if a given PFN has valid memmap
- * associated with it or not. This means that a struct page exists for this
- * pfn. The caller cannot assume the page is fully initialized in general.
- * Hotplugable pages might not have been onlined yet. pfn_to_online_page()
- * will ensure the struct page is fully online and initialized. Special pages
- * (e.g. ZONE_DEVICE) are never onlined and should be treated accordingly.
- *
- * In FLATMEM, it is expected that holes always have valid memmap as long as
- * there is valid PFNs either side of the hole. In SPARSEMEM, it is assumed
- * that a valid section has a memmap for the entire section.
- *
- * However, an ARM, and maybe other embedded architectures in the future
- * free memmap backing holes to save memory on the assumption the memmap is
- * never used. The page_zone linkages are then broken even though pfn_valid()
- * returns true. A walker of the full memmap must then do this additional
- * check to ensure the memmap they are looking at is sane by making sure
- * the zone and PFN linkages are still valid. This is expensive, but walkers
- * of the full memmap are extremely rare.
- */
-bool memmap_valid_within(unsigned long pfn,
- struct page *page, struct zone *zone);
-#else
-static inline bool memmap_valid_within(unsigned long pfn,
- struct page *page, struct zone *zone)
-{
- return true;
-}
-#endif /* CONFIG_ARCH_HAS_HOLES_MEMORYMODEL */
-
#endif /* !__GENERATING_BOUNDS.H */
#endif /* !__ASSEMBLY__ */
#endif /* _LINUX_MMZONE_H */
--- a/mm/mmzone.c~arm-remove-config_arch_has_holes_memorymodel
+++ a/mm/mmzone.c
@@ -72,20 +72,6 @@ struct zoneref *__next_zones_zonelist(st
return z;
}
-#ifdef CONFIG_ARCH_HAS_HOLES_MEMORYMODEL
-bool memmap_valid_within(unsigned long pfn,
- struct page *page, struct zone *zone)
-{
- if (page_to_pfn(page) != pfn)
- return false;
-
- if (page_zone(page) != zone)
- return false;
-
- return true;
-}
-#endif /* CONFIG_ARCH_HAS_HOLES_MEMORYMODEL */
-
void lruvec_init(struct lruvec *lruvec)
{
enum lru_list lru;
--- a/mm/vmstat.c~arm-remove-config_arch_has_holes_memorymodel
+++ a/mm/vmstat.c
@@ -1503,10 +1503,6 @@ static void pagetypeinfo_showblockcount_
if (!page)
continue;
- /* Watch for unexpected holes punched in the memmap */
- if (!memmap_valid_within(pfn, page, zone))
- continue;
-
if (page_zone(page) != zone)
continue;
_
Patches currently in -mm which might be from rppt@xxxxxxxxxxxxx are
mm-introduce-debug_pagealloc_map_pages-helper.patch
pm-hibernate-make-direct-map-manipulations-more-explicit.patch
arch-mm-restore-dependency-of-__kernel_map_pages-of-debug_pagealloc.patch
arch-mm-make-kernel_page_present-always-available.patch
alpha-switch-from-discontigmem-to-sparsemem.patch
ia64-remove-custom-__early_pfn_to_nid.patch
ia64-remove-ifdef-config_zone_dma32-statements.patch
ia64-discontig-paging_init-remove-local-max_pfn-calculation.patch
ia64-split-virtual-map-initialization-out-of-paging_init.patch
ia64-forbid-using-virtual_mem_map-with-flatmem.patch
ia64-make-sparsemem-default-and-disable-discontigmem.patch
arm-remove-config_arch_has_holes_memorymodel.patch
arm-arm64-move-free_unused_memmap-to-generic-mm.patch
arc-use-flatmem-with-freeing-of-unused-memory-map-instead-of-discontigmem.patch
m68k-mm-make-node-data-and-node-setup-depend-on-config_discontigmem.patch
m68k-mm-enable-use-of-generic-memory_modelh-for-discontigmem.patch
m68k-deprecate-discontigmem.patch
