Messages in this thread | | | From | Nanyong Sun <> | Subject | [PATCH -next 0/2] riscv/mm: Enable THP migration | Date | Tue, 23 Nov 2021 22:06:36 +0800 |
| |
This series enables THP migration on riscv via ARCH_ENABLE_THP_MIGRATION. But first this adjusts PAGE_PROT_NONE to satisfy generic memory semantics like the behavior of pmd_present() and pmd_trans_huge() when in THP splitting or migration.
This feature can reduce the time of THP migration by not splits THP before migration and can guarantee the pages after migration are still contiguous.[1]
I have tested the below test case on qemu based on riscv after enabling this feature, the throughput of THP migration gains 13x performance improvement: https://github.com/x-y-z/thp-migration-bench
I also have tested and passed the test cases under tools/testing/selftests/vm.
[1]: https://lwn.net/Articles/723764/
Nanyong Sun (2): riscv/mm: Adjust PAGE_PROT_NONE to comply with THP semantics riscv/mm: Enable THP migration
arch/riscv/Kconfig | 1 + arch/riscv/include/asm/pgtable-bits.h | 2 +- arch/riscv/include/asm/pgtable.h | 16 +++++++++++----- 3 files changed, 13 insertions(+), 6 deletions(-)
-- 2.25.1
| |