From 06a33d024838414432b6c0f51f994e7f1695b74f Mon Sep 17 00:00:00 2001 From: Pu Lehui Date: Mon, 15 Jan 2024 13:12:35 +0000 Subject: riscv, bpf: Optimize bswap insns with Zbb support MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Optimize bswap instructions by rev8 Zbb instruction conbined with srli instruction. And Optimize 16-bit zero-extension with Zbb support. Signed-off-by: Pu Lehui Signed-off-by: Daniel Borkmann Tested-by: Björn Töpel Acked-by: Björn Töpel Link: https://lore.kernel.org/bpf/20240115131235.2914289-7-pulehui@huaweicloud.com --- arch/riscv/net/bpf_jit.h | 69 +++++++++++++++++++++++++++++++++++++++++ arch/riscv/net/bpf_jit_comp64.c | 50 ++--------------------------- 2 files changed, 71 insertions(+), 48 deletions(-) diff --git a/arch/riscv/net/bpf_jit.h b/arch/riscv/net/bpf_jit.h index b00c5c0591d2..8b35f12a4452 100644 --- a/arch/riscv/net/bpf_jit.h +++ b/arch/riscv/net/bpf_jit.h @@ -1146,12 +1146,81 @@ static inline void emit_sextw(u8 rd, u8 rs, struct rv_jit_context *ctx) emit_addiw(rd, rs, 0, ctx); } +static inline void emit_zexth(u8 rd, u8 rs, struct rv_jit_context *ctx) +{ + if (rvzbb_enabled()) { + emit(rvzbb_zexth(rd, rs), ctx); + return; + } + + emit_slli(rd, rs, 48, ctx); + emit_srli(rd, rd, 48, ctx); +} + static inline void emit_zextw(u8 rd, u8 rs, struct rv_jit_context *ctx) { emit_slli(rd, rs, 32, ctx); emit_srli(rd, rd, 32, ctx); } +static inline void emit_bswap(u8 rd, s32 imm, struct rv_jit_context *ctx) +{ + if (rvzbb_enabled()) { + int bits = 64 - imm; + + emit(rvzbb_rev8(rd, rd), ctx); + if (bits) + emit_srli(rd, rd, bits, ctx); + return; + } + + emit_li(RV_REG_T2, 0, ctx); + + emit_andi(RV_REG_T1, rd, 0xff, ctx); + emit_add(RV_REG_T2, RV_REG_T2, RV_REG_T1, ctx); + emit_slli(RV_REG_T2, RV_REG_T2, 8, ctx); + emit_srli(rd, rd, 8, ctx); + if (imm == 16) + goto out_be; + + emit_andi(RV_REG_T1, rd, 0xff, ctx); + emit_add(RV_REG_T2, RV_REG_T2, RV_REG_T1, ctx); + emit_slli(RV_REG_T2, RV_REG_T2, 8, ctx); + emit_srli(rd, rd, 8, ctx); + + emit_andi(RV_REG_T1, rd, 0xff, ctx); + emit_add(RV_REG_T2, RV_REG_T2, RV_REG_T1, ctx); + emit_slli(RV_REG_T2, RV_REG_T2, 8, ctx); + emit_srli(rd, rd, 8, ctx); + if (imm == 32) + goto out_be; + + emit_andi(RV_REG_T1, rd, 0xff, ctx); + emit_add(RV_REG_T2, RV_REG_T2, RV_REG_T1, ctx); + emit_slli(RV_REG_T2, RV_REG_T2, 8, ctx); + emit_srli(rd, rd, 8, ctx); + + emit_andi(RV_REG_T1, rd, 0xff, ctx); + emit_add(RV_REG_T2, RV_REG_T2, RV_REG_T1, ctx); + emit_slli(RV_REG_T2, RV_REG_T2, 8, ctx); + emit_srli(rd, rd, 8, ctx); + + emit_andi(RV_REG_T1, rd, 0xff, ctx); + emit_add(RV_REG_T2, RV_REG_T2, RV_REG_T1, ctx); + emit_slli(RV_REG_T2, RV_REG_T2, 8, ctx); + emit_srli(rd, rd, 8, ctx); + + emit_andi(RV_REG_T1, rd, 0xff, ctx); + emit_add(RV_REG_T2, RV_REG_T2, RV_REG_T1, ctx); + emit_slli(RV_REG_T2, RV_REG_T2, 8, ctx); + emit_srli(rd, rd, 8, ctx); +out_be: + emit_andi(RV_REG_T1, rd, 0xff, ctx); + emit_add(RV_REG_T2, RV_REG_T2, RV_REG_T1, ctx); + + emit_mv(rd, RV_REG_T2, ctx); +} + #endif /* __riscv_xlen == 64 */ void bpf_jit_build_prologue(struct rv_jit_context *ctx); diff --git a/arch/riscv/net/bpf_jit_comp64.c b/arch/riscv/net/bpf_jit_comp64.c index fc1a334e2f70..fda6b4f6a4c1 100644 --- a/arch/riscv/net/bpf_jit_comp64.c +++ b/arch/riscv/net/bpf_jit_comp64.c @@ -1177,8 +1177,7 @@ int bpf_jit_emit_insn(const struct bpf_insn *insn, struct rv_jit_context *ctx, case BPF_ALU | BPF_END | BPF_FROM_LE: switch (imm) { case 16: - emit_slli(rd, rd, 48, ctx); - emit_srli(rd, rd, 48, ctx); + emit_zexth(rd, rd, ctx); break; case 32: if (!aux->verifier_zext) @@ -1189,54 +1188,9 @@ int bpf_jit_emit_insn(const struct bpf_insn *insn, struct rv_jit_context *ctx, break; } break; - case BPF_ALU | BPF_END | BPF_FROM_BE: case BPF_ALU64 | BPF_END | BPF_FROM_LE: - emit_li(RV_REG_T2, 0, ctx); - - emit_andi(RV_REG_T1, rd, 0xff, ctx); - emit_add(RV_REG_T2, RV_REG_T2, RV_REG_T1, ctx); - emit_slli(RV_REG_T2, RV_REG_T2, 8, ctx); - emit_srli(rd, rd, 8, ctx); - if (imm == 16) - goto out_be; - - emit_andi(RV_REG_T1, rd, 0xff, ctx); - emit_add(RV_REG_T2, RV_REG_T2, RV_REG_T1, ctx); - emit_slli(RV_REG_T2, RV_REG_T2, 8, ctx); - emit_srli(rd, rd, 8, ctx); - - emit_andi(RV_REG_T1, rd, 0xff, ctx); - emit_add(RV_REG_T2, RV_REG_T2, RV_REG_T1, ctx); - emit_slli(RV_REG_T2, RV_REG_T2, 8, ctx); - emit_srli(rd, rd, 8, ctx); - if (imm == 32) - goto out_be; - - emit_andi(RV_REG_T1, rd, 0xff, ctx); - emit_add(RV_REG_T2, RV_REG_T2, RV_REG_T1, ctx); - emit_slli(RV_REG_T2, RV_REG_T2, 8, ctx); - emit_srli(rd, rd, 8, ctx); - - emit_andi(RV_REG_T1, rd, 0xff, ctx); - emit_add(RV_REG_T2, RV_REG_T2, RV_REG_T1, ctx); - emit_slli(RV_REG_T2, RV_REG_T2, 8, ctx); - emit_srli(rd, rd, 8, ctx); - - emit_andi(RV_REG_T1, rd, 0xff, ctx); - emit_add(RV_REG_T2, RV_REG_T2, RV_REG_T1, ctx); - emit_slli(RV_REG_T2, RV_REG_T2, 8, ctx); - emit_srli(rd, rd, 8, ctx); - - emit_andi(RV_REG_T1, rd, 0xff, ctx); - emit_add(RV_REG_T2, RV_REG_T2, RV_REG_T1, ctx); - emit_slli(RV_REG_T2, RV_REG_T2, 8, ctx); - emit_srli(rd, rd, 8, ctx); -out_be: - emit_andi(RV_REG_T1, rd, 0xff, ctx); - emit_add(RV_REG_T2, RV_REG_T2, RV_REG_T1, ctx); - - emit_mv(rd, RV_REG_T2, ctx); + emit_bswap(rd, imm, ctx); break; /* dst = imm */ -- cgit