[PATCH RESEND bpf-next v3 4/6] riscv, bpf: Add necessary Zbb instructions
From: Pu Lehui <hidden>
Date: 2024-01-15 13:12:11
Also in:
bpf, linux-riscv
Subsystem:
bpf jit for risc-v (32-bit), bpf jit for risc-v (64-bit), bpf [general] (safe dynamic programs and tools), risc-v architecture, the rest · Maintainers:
Luke Nelson, Xi Wang, Björn Töpel, Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko, Eduard Zingerman, Kumar Kartikeya Dwivedi, Paul Walmsley, Palmer Dabbelt, Albert Ou, Linus Torvalds
From: Pu Lehui <pulehui@huawei.com> 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. Link: https://github.com/riscv/riscv-bitmanip/releases/download/1.0.0/bitmanip-1.0.0-38-g865e7a7.pdf [0] Signed-off-by: Pu Lehui <pulehui@huawei.com> --- arch/riscv/net/bpf_jit.h | 32 ++++++++++++++++++++++++++++++++ 1 file changed, 32 insertions(+)
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. *
--
2.34.1