From 647b93f65daa128d9a0e4aac744a5fcf5f58b2d2 Mon Sep 17 00:00:00 2001 From: Pu Lehui Date: Mon, 15 Jan 2024 13:12:33 +0000 Subject: riscv, bpf: Add necessary Zbb instructions MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Add necessary Zbb instructions introduced by [0] to reduce code size and improve performance of RV64 JIT. Meanwhile, a runtime deteted helper is added to check whether the CPU supports Zbb instructions. Signed-off-by: Pu Lehui Signed-off-by: Daniel Borkmann Tested-by: Björn Töpel Acked-by: Björn Töpel Link: https://github.com/riscv/riscv-bitmanip/releases/download/1.0.0/bitmanip-1.0.0-38-g865e7a7.pdf [0] Link: https://lore.kernel.org/bpf/20240115131235.2914289-5-pulehui@huaweicloud.com --- arch/riscv/net/bpf_jit.h | 32 ++++++++++++++++++++++++++++++++ 1 file changed, 32 insertions(+) (limited to 'arch/riscv/net/bpf_jit.h') diff --git a/arch/riscv/net/bpf_jit.h b/arch/riscv/net/bpf_jit.h index e30501b46f8f..51f6d214086f 100644 --- a/arch/riscv/net/bpf_jit.h +++ b/arch/riscv/net/bpf_jit.h @@ -18,6 +18,11 @@ static inline bool rvc_enabled(void) return IS_ENABLED(CONFIG_RISCV_ISA_C); } +static inline bool rvzbb_enabled(void) +{ + return IS_ENABLED(CONFIG_RISCV_ISA_ZBB) && riscv_has_extension_likely(RISCV_ISA_EXT_ZBB); +} + enum { RV_REG_ZERO = 0, /* The constant value 0 */ RV_REG_RA = 1, /* Return address */ @@ -730,6 +735,33 @@ static inline u16 rvc_swsp(u32 imm8, u8 rs2) return rv_css_insn(0x6, imm, rs2, 0x2); } +/* RVZBB instrutions. */ +static inline u32 rvzbb_sextb(u8 rd, u8 rs1) +{ + return rv_i_insn(0x604, rs1, 1, rd, 0x13); +} + +static inline u32 rvzbb_sexth(u8 rd, u8 rs1) +{ + return rv_i_insn(0x605, rs1, 1, rd, 0x13); +} + +static inline u32 rvzbb_zexth(u8 rd, u8 rs) +{ + if (IS_ENABLED(CONFIG_64BIT)) + return rv_i_insn(0x80, rs, 4, rd, 0x3b); + + return rv_i_insn(0x80, rs, 4, rd, 0x33); +} + +static inline u32 rvzbb_rev8(u8 rd, u8 rs) +{ + if (IS_ENABLED(CONFIG_64BIT)) + return rv_i_insn(0x6b8, rs, 5, rd, 0x13); + + return rv_i_insn(0x698, rs, 5, rd, 0x13); +} + /* * RV64-only instructions. * -- cgit v1.2.3