[RFC PATCH v1 0/3] arm64: tlb: add support for TTL field

From: Zhenyu Ye
Date: Tue Mar 10 2020 - 22:56:30 EST


ARMv8.4-TTL provides the TTL field in tlbi instruction to indicate
the level of translation table walk holding the leaf entry for the
address that is being invalidated. Hardware can use this information
to determine if there was a risk of splintering.

This set of patches adds TTL field to __TLBI_ADDR, and uses
Architecture-specific MM context to pass the TTL value to tlb interface.

The default value of TTL is 0, which will not have any impact on the
TLB maintenance instructions. The last patch trys to use TTL field in
some obviously tlb-flush interface.

Zhenyu Ye (3):
arm64: tlb: add TTL field to __TLBI_ADDR
arm64: tlb: use mm_struct.context.flags to indicate TTL
arm64: tlb: add support for TTL in some functions

arch/arm64/include/asm/cpucaps.h | 3 ++-
arch/arm64/include/asm/mmu.h | 11 ++++++++++
arch/arm64/include/asm/sysreg.h | 4 ++++
arch/arm64/include/asm/tlb.h | 3 +++
arch/arm64/include/asm/tlbflush.h | 35 +++++++++++++++++++++++--------
arch/arm64/kernel/cpufeature.c | 10 +++++++++
arch/arm64/kernel/sys_compat.c | 2 +-
arch/arm64/mm/hugetlbpage.c | 2 ++
8 files changed, 59 insertions(+), 11 deletions(-)

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2.19.1