arm64: Kconfig: Remove ARCH_HAS_HOLES_MEMORYMODEL (8a695a58) · Commits · 戴 / test

include/linux/mmzone.h describes ARCH_HAS_HOLES_MEMORYMODEL as relevant when parts the memmap have been free()d. This would happen on systems where memory is smaller than a sparsemem-section, and the extra struct pages are expensive. pfn_valid() on these systems returns true for the whole sparsemem-section, so an extra memmap_valid_within() check is needed. On arm64 we have nomap memory, so always provide pfn_valid() to test for nomap pages. This means ARCH_HAS_HOLES_MEMORYMODEL's extra checks are already rolled up into pfn_valid(). Remove it. Acked-by:

Will Deacon <will.deacon@arm.com> Signed-off-by:

James Morse <james.morse@arm.com> Signed-off-by:

Catalin Marinas <catalin.marinas@arm.com>

arch/arm64/Kconfig

+1 −4

Original line number	Diff line number	Diff line
		@@ -771,9 +771,6 @@ source kernel/Kconfig.hz
		config ARCH_SUPPORTS_DEBUG_PAGEALLOC
		def_bool y

		config ARCH_HAS_HOLES_MEMORYMODEL
		def_bool y if SPARSEMEM

		config ARCH_SPARSEMEM_ENABLE
		def_bool y
		select SPARSEMEM_VMEMMAP_ENABLE
		@@ -788,7 +785,7 @@ config ARCH_FLATMEM_ENABLE
		def_bool !NUMA

		config HAVE_ARCH_PFN_VALID
		def_bool ARCH_HAS_HOLES_MEMORYMODEL \|\| !SPARSEMEM
		def_bool y

		config HW_PERF_EVENTS
		def_bool y

arch/arm64/include/asm/page.h

+0 −2

Original line number	Diff line number	Diff line
		@@ -37,9 +37,7 @@ extern void clear_page(void *to);

		typedef struct page *pgtable_t;

		#ifdef CONFIG_HAVE_ARCH_PFN_VALID
		extern int pfn_valid(unsigned long);
		#endif

		#include <asm/memory.h>

arch/arm64/mm/init.c

+0 −2

Original line number	Diff line number	Diff line
		@@ -284,7 +284,6 @@ static void __init zone_sizes_init(unsigned long min, unsigned long max)

		#endif /* CONFIG_NUMA */

		#ifdef CONFIG_HAVE_ARCH_PFN_VALID
		int pfn_valid(unsigned long pfn)
		{
		phys_addr_t addr = pfn << PAGE_SHIFT;
		@@ -294,7 +293,6 @@ int pfn_valid(unsigned long pfn)
		return memblock_is_map_memory(addr);
		}
		EXPORT_SYMBOL(pfn_valid);
		#endif

		#ifndef CONFIG_SPARSEMEM
		static void __init arm64_memory_present(void)

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