Unverified Commit d062a79b authored by Nanyong Sun's avatar Nanyong Sun Committed by Palmer Dabbelt
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riscv/mm: Enable THP migration 



Add two THP helpers required to create PMD migration swap entries,
and enable THP migration via ARCH_ENABLE_THP_MIGRATION. This can
reduce time of THP migration without splitting and guarantee the
migrated pages are still contiguous.

Signed-off-by: default avatarNanyong Sun <sunnanyong@huawei.com>
Signed-off-by: default avatarPalmer Dabbelt <palmer@rivosinc.com>
parent fba88ede

arch/riscv/Kconfig

+1 −0
Original line number Diff line number Diff line
@@ -76,6 +76,7 @@ config RISCV 
	select HAVE_ARCH_SECCOMP_FILTER

	select HAVE_ARCH_TRACEHOOK

	select HAVE_ARCH_TRANSPARENT_HUGEPAGE if 64BIT && MMU

	select ARCH_ENABLE_THP_MIGRATION if TRANSPARENT_HUGEPAGE

	select HAVE_ARCH_THREAD_STRUCT_WHITELIST

	select HAVE_ARCH_VMAP_STACK if MMU && 64BIT

	select HAVE_ASM_MODVERSIONS

arch/riscv/include/asm/pgtable.h

+5 −0
Original line number Diff line number Diff line
@@ -649,6 +649,11 @@ static inline pmd_t pmdp_establish(struct vm_area_struct *vma, 
#define __pte_to_swp_entry(pte)	((swp_entry_t) { pte_val(pte) })

#define __swp_entry_to_pte(x)	((pte_t) { (x).val })



#ifdef CONFIG_ARCH_ENABLE_THP_MIGRATION

#define __pmd_to_swp_entry(pmd) ((swp_entry_t) { pmd_val(pmd) })

#define __swp_entry_to_pmd(swp) __pmd((swp).val)

#endif /* CONFIG_ARCH_ENABLE_THP_MIGRATION */



/*

 * In the RV64 Linux scheme, we give the user half of the virtual-address space

 * and give the kernel the other (upper) half.