From 87f81e66e2e84c7e6056413703d732a99c20c09b Mon Sep 17 00:00:00 2001 From: Jisheng Zhang Date: Mon, 29 Aug 2022 22:57:42 +0800 Subject: [PATCH] riscv: enable THP_SWAP for RV64 I have a Sipeed Lichee RV dock board which only has 512MB DDR, so memory optimizations such as swap on zram are helpful. As is seen in commit d0637c505f8a ("arm64: enable THP_SWAP for arm64") and commit bd4c82c22c367e ("mm, THP, swap: delay splitting THP after swapped out"), THP_SWAP can improve the swap throughput significantly. Enable THP_SWAP for RV64, testing the micro-benchmark which is introduced by commit d0637c505f8a ("arm64: enable THP_SWAP for arm64") shows below numbers on the Lichee RV dock board: swp out bandwidth w/o patch: 66908 bytes/ms (mean of 10 tests) swp out bandwidth w/ patch: 322638 bytes/ms (mean of 10 tests) Improved by 382%! Signed-off-by: Jisheng Zhang Reviewed-by: Andrew Jones Reviewed-by: Conor Dooley Link: https://lore.kernel.org/r/20220829145742.3139-1-jszhang@kernel.org/ Signed-off-by: Palmer Dabbelt --- arch/riscv/Kconfig | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig index f06ce10a589b..0dd2595e3505 100644 --- a/arch/riscv/Kconfig +++ b/arch/riscv/Kconfig @@ -45,6 +45,7 @@ config RISCV select ARCH_WANT_FRAME_POINTERS select ARCH_WANT_GENERAL_HUGETLB select ARCH_WANT_HUGE_PMD_SHARE if 64BIT + select ARCH_WANTS_THP_SWAP if HAVE_ARCH_TRANSPARENT_HUGEPAGE select BINFMT_FLAT_NO_DATA_START_OFFSET if !MMU select BUILDTIME_TABLE_SORT if MMU select CLONE_BACKWARDS -- 2.20.1