| Message ID | 20201101170454.9567-9-rppt@kernel.org |
|---|---|
| State | New |
| Headers | show |
| Series | arch, mm: deprecate DISCONTIGMEM | expand |
On 01.11.20 18:04, Mike Rapoport wrote: > From: Mike Rapoport <rppt@linux.ibm.com> > > 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. > > Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> > --- > 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(-) > > diff --git a/Documentation/vm/memory-model.rst b/Documentation/vm/memory-model.rst > index 9daadf9faba1..ce398a7dc6cd 100644 > --- a/Documentation/vm/memory-model.rst > +++ b/Documentation/vm/memory-model.rst > @@ -51,8 +51,7 @@ call :c:func:`free_area_init` function. Yet, the mappings array is not > 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. > diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig > index fe2f17eb2b50..83adc46c1e67 100644 > --- a/arch/arm/Kconfig > +++ b/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" > diff --git a/arch/arm/mach-bcm/Kconfig b/arch/arm/mach-bcm/Kconfig > index ae790908fc74..9b594ae98153 100644 > --- a/arch/arm/mach-bcm/Kconfig > +++ b/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 > diff --git a/arch/arm/mach-davinci/Kconfig b/arch/arm/mach-davinci/Kconfig > index f56ff8c24043..de11030748d0 100644 > --- a/arch/arm/mach-davinci/Kconfig > +++ b/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 > diff --git a/arch/arm/mach-exynos/Kconfig b/arch/arm/mach-exynos/Kconfig > index d2d249706ebb..56d272967fc0 100644 > --- a/arch/arm/mach-exynos/Kconfig > +++ b/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 > diff --git a/arch/arm/mach-highbank/Kconfig b/arch/arm/mach-highbank/Kconfig > index 1bc68913d62c..9de38ce8124f 100644 > --- a/arch/arm/mach-highbank/Kconfig > +++ b/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 > diff --git a/arch/arm/mach-omap2/Kconfig b/arch/arm/mach-omap2/Kconfig > index 3ee7bdff86b2..89fe1572c142 100644 > --- a/arch/arm/mach-omap2/Kconfig > +++ b/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 > diff --git a/arch/arm/mach-s5pv210/Kconfig b/arch/arm/mach-s5pv210/Kconfig > index 95d4e8284866..d644b45bc29d 100644 > --- a/arch/arm/mach-s5pv210/Kconfig > +++ b/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 > diff --git a/arch/arm/mach-tango/Kconfig b/arch/arm/mach-tango/Kconfig > index 25b2fd434861..a9eeda36aeb1 100644 > --- a/arch/arm/mach-tango/Kconfig > +++ b/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 > diff --git a/fs/proc/kcore.c b/fs/proc/kcore.c > index e502414b3556..4d2e64e9016c 100644 > --- a/fs/proc/kcore.c > +++ b/fs/proc/kcore.c > @@ -193,8 +193,6 @@ kclist_add_private(unsigned long pfn, unsigned long nr_pages, void *arg) > 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) > diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h > index 876600a6e891..7385871768d4 100644 > --- a/include/linux/mmzone.h > +++ b/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 */ > diff --git a/mm/mmzone.c b/mm/mmzone.c > index 4686fdc23bb9..f337831affc2 100644 > --- a/mm/mmzone.c > +++ b/mm/mmzone.c > @@ -72,20 +72,6 @@ struct zoneref *__next_zones_zonelist(struct zoneref *z, > 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; > diff --git a/mm/vmstat.c b/mm/vmstat.c > index 698bc0bc18d1..e292e63afebf 100644 > --- a/mm/vmstat.c > +++ b/mm/vmstat.c > @@ -1503,10 +1503,6 @@ static void pagetypeinfo_showblockcount_print(struct seq_file *m, > if (!page) > continue; > > - /* Watch for unexpected holes punched in the memmap */ > - if (!memmap_valid_within(pfn, page, zone)) > - continue; > - Right, pfn_to_online_page() -> pfn_valid() / pfn_valid_within() should handle that. Acked-by: David Hildenbrand <david@redhat.com>
diff --git a/Documentation/vm/memory-model.rst b/Documentation/vm/memory-model.rst index 9daadf9faba1..ce398a7dc6cd 100644 --- a/Documentation/vm/memory-model.rst +++ b/Documentation/vm/memory-model.rst @@ -51,8 +51,7 @@ call :c:func:`free_area_init` function. Yet, the mappings array is not 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. diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index fe2f17eb2b50..83adc46c1e67 100644 --- a/arch/arm/Kconfig +++ b/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" diff --git a/arch/arm/mach-bcm/Kconfig b/arch/arm/mach-bcm/Kconfig index ae790908fc74..9b594ae98153 100644 --- a/arch/arm/mach-bcm/Kconfig +++ b/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 diff --git a/arch/arm/mach-davinci/Kconfig b/arch/arm/mach-davinci/Kconfig index f56ff8c24043..de11030748d0 100644 --- a/arch/arm/mach-davinci/Kconfig +++ b/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 diff --git a/arch/arm/mach-exynos/Kconfig b/arch/arm/mach-exynos/Kconfig index d2d249706ebb..56d272967fc0 100644 --- a/arch/arm/mach-exynos/Kconfig +++ b/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 diff --git a/arch/arm/mach-highbank/Kconfig b/arch/arm/mach-highbank/Kconfig index 1bc68913d62c..9de38ce8124f 100644 --- a/arch/arm/mach-highbank/Kconfig +++ b/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 diff --git a/arch/arm/mach-omap2/Kconfig b/arch/arm/mach-omap2/Kconfig index 3ee7bdff86b2..89fe1572c142 100644 --- a/arch/arm/mach-omap2/Kconfig +++ b/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 diff --git a/arch/arm/mach-s5pv210/Kconfig b/arch/arm/mach-s5pv210/Kconfig index 95d4e8284866..d644b45bc29d 100644 --- a/arch/arm/mach-s5pv210/Kconfig +++ b/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 diff --git a/arch/arm/mach-tango/Kconfig b/arch/arm/mach-tango/Kconfig index 25b2fd434861..a9eeda36aeb1 100644 --- a/arch/arm/mach-tango/Kconfig +++ b/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 diff --git a/fs/proc/kcore.c b/fs/proc/kcore.c index e502414b3556..4d2e64e9016c 100644 --- a/fs/proc/kcore.c +++ b/fs/proc/kcore.c @@ -193,8 +193,6 @@ kclist_add_private(unsigned long pfn, unsigned long nr_pages, void *arg) 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) diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h index 876600a6e891..7385871768d4 100644 --- a/include/linux/mmzone.h +++ b/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 */ diff --git a/mm/mmzone.c b/mm/mmzone.c index 4686fdc23bb9..f337831affc2 100644 --- a/mm/mmzone.c +++ b/mm/mmzone.c @@ -72,20 +72,6 @@ struct zoneref *__next_zones_zonelist(struct zoneref *z, 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; diff --git a/mm/vmstat.c b/mm/vmstat.c index 698bc0bc18d1..e292e63afebf 100644 --- a/mm/vmstat.c +++ b/mm/vmstat.c @@ -1503,10 +1503,6 @@ static void pagetypeinfo_showblockcount_print(struct seq_file *m, 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;