[PATCH RFC 2/2] LoongArch: BPF: Eliminate zero/sign extensions for 32-bit operations
Tiezhu Yang <[email protected]>
| Newsgroups | dev.linux.lists.loongarch,org.kernel.vger.bpf,org.kernel.vger.linux-kernel |
|---|---|
| Message-ID | <[email protected]> |
Eliminate frequent and redundant zero-extensions and sign-extensions for 32-bit operations. This prevents potential functional bugs caused by incorrect extension selections and reduces runtime overhead. For explicit 32-bit zero-extensions (imm == 1), generate a `lu32id` instruction to guarantee the zero-extended form when they cannot be bypassed by the look-ahead logic. For other 32-bit arithmetic, emit LoongArch native 32-bit instructions which inherently perform hardware-level sign-extension. For bitwise logical instructions, append `addiw dst, dst, 0` to enforce the standard sign-extended form of the result. For 32-bit signed conditional jumps, remove redundant register copies and pre-jump `emit_sext_32` helpers to leverage native branching, as operands are now natively sign-extended. For 32-bit unsigned conditional jumps, use `bstrpickd` to clear the upper 32 bits of the operands. For JSET bit-testing, maintain `addiw t1, t1, 0` in the jmp32 path to ensure correctness. With this patch, deliver an optimal native execution stream and reduce the overall JIT image size. Signed-off-by: Tiezhu Yang <[email protected]> --- arch/loongarch/net/bpf_jit.c | 357 +++++++++++++++++++---------------- arch/loongarch/net/bpf_jit.h | 25 +-- 2 files changed, 198 insertions(+), 184 deletions(-) diff --git a/arch/loongarch/net/bpf_jit.c b/arch/loongarch/net/bpf_jit.c index b8cef3ea5c6d..08a5903dd5a3 100644 --- a/arch/loongarch/net/bpf_jit.c +++ b/arch/loongarch/net/bpf_jit.c @@ -209,7 +209,7 @@ static void build_prologue(struct jit_ctx *ctx) ctx->stack_size = stack_adjust; if (ctx->arena_vm_start) - move_imm(ctx, REG_ARENA, ctx->arena_vm_start, false); + move_imm(ctx, REG_ARENA, ctx->arena_vm_start); } static void __build_epilogue(struct jit_ctx *ctx, bool is_tail_call) @@ -311,7 +311,6 @@ static int emit_bpf_tail_call(struct jit_ctx *ctx, int insn) * goto out; */ tc_ninsn = insn ? ctx->offset[insn+1] - ctx->offset[insn] : ctx->offset[0]; - emit_zext_32(ctx, a2, true); off = offsetof(struct bpf_array, map.max_entries); emit_insn(ctx, ldwu, t1, a1, off); @@ -361,7 +360,7 @@ static int emit_bpf_tail_call(struct jit_ctx *ctx, int insn) static void emit_store_stack_imm64(struct jit_ctx *ctx, int reg, int stack_off, u64 imm64) { - move_imm(ctx, reg, imm64, false); + move_imm(ctx, reg, imm64); emit_insn(ctx, std, reg, LOONGARCH_GPR_FP, stack_off); } @@ -377,7 +376,7 @@ static int emit_atomic_rmw(const struct bpf_insn *insn, struct jit_ctx *ctx) const s32 imm = insn->imm; const bool isdw = BPF_SIZE(insn->code) == BPF_DW; - move_imm(ctx, t1, off, false); + move_imm(ctx, t1, off); emit_insn(ctx, addd, t1, dst, t1); move_reg(ctx, t3, src); @@ -434,7 +433,6 @@ static int emit_atomic_rmw(const struct bpf_insn *insn, struct jit_ctx *ctx) return -EINVAL; } emit_insn(ctx, amaddb, src, t1, t3); - emit_zext_32(ctx, src, true); break; case BPF_H: if (!cpu_has_lam_bh) { @@ -442,11 +440,9 @@ static int emit_atomic_rmw(const struct bpf_insn *insn, struct jit_ctx *ctx) return -EINVAL; } emit_insn(ctx, amaddh, src, t1, t3); - emit_zext_32(ctx, src, true); break; case BPF_W: emit_insn(ctx, amaddw, src, t1, t3); - emit_zext_32(ctx, src, true); break; case BPF_DW: emit_insn(ctx, amaddd, src, t1, t3); @@ -454,28 +450,22 @@ static int emit_atomic_rmw(const struct bpf_insn *insn, struct jit_ctx *ctx) } break; case BPF_AND | BPF_FETCH: - if (isdw) { + if (isdw) emit_insn(ctx, amandd, src, t1, t3); - } else { + else emit_insn(ctx, amandw, src, t1, t3); - emit_zext_32(ctx, src, true); - } break; case BPF_OR | BPF_FETCH: - if (isdw) { + if (isdw) emit_insn(ctx, amord, src, t1, t3); - } else { + else emit_insn(ctx, amorw, src, t1, t3); - emit_zext_32(ctx, src, true); - } break; case BPF_XOR | BPF_FETCH: - if (isdw) { + if (isdw) emit_insn(ctx, amxord, src, t1, t3); - } else { + else emit_insn(ctx, amxorw, src, t1, t3); - emit_zext_32(ctx, src, true); - } break; /* src = atomic_xchg(dst + off, src); */ case BPF_XCHG: @@ -486,7 +476,6 @@ static int emit_atomic_rmw(const struct bpf_insn *insn, struct jit_ctx *ctx) return -EINVAL; } emit_insn(ctx, amswapb, src, t1, t3); - emit_zext_32(ctx, src, true); break; case BPF_H: if (!cpu_has_lam_bh) { @@ -494,11 +483,9 @@ static int emit_atomic_rmw(const struct bpf_insn *insn, struct jit_ctx *ctx) return -EINVAL; } emit_insn(ctx, amswaph, src, t1, t3); - emit_zext_32(ctx, src, true); break; case BPF_W: emit_insn(ctx, amswapw, src, t1, t3); - emit_zext_32(ctx, src, true); break; case BPF_DW: emit_insn(ctx, amswapd, src, t1, t3); @@ -516,13 +503,10 @@ static int emit_atomic_rmw(const struct bpf_insn *insn, struct jit_ctx *ctx) emit_insn(ctx, beq, t3, LOONGARCH_GPR_ZERO, -4); } else { emit_insn(ctx, llw, r0, t1, 0); - emit_zext_32(ctx, t2, true); - emit_zext_32(ctx, r0, true); emit_insn(ctx, bne, t2, r0, 4); move_reg(ctx, t3, src); emit_insn(ctx, scw, t3, t1, 0); emit_insn(ctx, beq, t3, LOONGARCH_GPR_ZERO, -6); - emit_zext_32(ctx, r0, true); } break; default: @@ -549,7 +533,7 @@ static int emit_atomic_ld_st(const struct bpf_insn *insn, struct jit_ctx *ctx) if (is_signed_imm12(off)) { emit_insn(ctx, ldbu, dst, src, off); } else { - move_imm(ctx, t1, off, false); + move_imm(ctx, t1, off); emit_insn(ctx, ldxbu, dst, src, t1); } break; @@ -557,7 +541,7 @@ static int emit_atomic_ld_st(const struct bpf_insn *insn, struct jit_ctx *ctx) if (is_signed_imm12(off)) { emit_insn(ctx, ldhu, dst, src, off); } else { - move_imm(ctx, t1, off, false); + move_imm(ctx, t1, off); emit_insn(ctx, ldxhu, dst, src, t1); } break; @@ -565,7 +549,7 @@ static int emit_atomic_ld_st(const struct bpf_insn *insn, struct jit_ctx *ctx) if (is_signed_imm12(off)) { emit_insn(ctx, ldwu, dst, src, off); } else { - move_imm(ctx, t1, off, false); + move_imm(ctx, t1, off); emit_insn(ctx, ldxwu, dst, src, t1); } break; @@ -573,7 +557,7 @@ static int emit_atomic_ld_st(const struct bpf_insn *insn, struct jit_ctx *ctx) if (is_signed_imm12(off)) { emit_insn(ctx, ldd, dst, src, off); } else { - move_imm(ctx, t1, off, false); + move_imm(ctx, t1, off); emit_insn(ctx, ldxd, dst, src, t1); } break; @@ -596,7 +580,7 @@ static int emit_atomic_ld_st(const struct bpf_insn *insn, struct jit_ctx *ctx) if (is_signed_imm12(off)) { emit_insn(ctx, stb, src, dst, off); } else { - move_imm(ctx, t1, off, false); + move_imm(ctx, t1, off); emit_insn(ctx, stxb, src, dst, t1); } break; @@ -604,7 +588,7 @@ static int emit_atomic_ld_st(const struct bpf_insn *insn, struct jit_ctx *ctx) if (is_signed_imm12(off)) { emit_insn(ctx, sth, src, dst, off); } else { - move_imm(ctx, t1, off, false); + move_imm(ctx, t1, off); emit_insn(ctx, stxh, src, dst, t1); } break; @@ -612,7 +596,7 @@ static int emit_atomic_ld_st(const struct bpf_insn *insn, struct jit_ctx *ctx) if (is_signed_imm12(off)) { emit_insn(ctx, stw, src, dst, off); } else { - move_imm(ctx, t1, off, false); + move_imm(ctx, t1, off); emit_insn(ctx, stxw, src, dst, t1); } break; @@ -620,7 +604,7 @@ static int emit_atomic_ld_st(const struct bpf_insn *insn, struct jit_ctx *ctx) if (is_signed_imm12(off)) { emit_insn(ctx, std, src, dst, off); } else { - move_imm(ctx, t1, off, false); + move_imm(ctx, t1, off); emit_insn(ctx, stxd, src, dst, t1); } break; @@ -741,28 +725,32 @@ static int build_insn(const struct bpf_insn *insn, struct jit_ctx *ctx, bool ext switch (code) { /* dst = src */ case BPF_ALU | BPF_MOV | BPF_X: + if (imm == 1) { + emit_insn(ctx, lu32id, reg, 0); + break; + } + + emit_insn(ctx, addw, dst, src, LOONGARCH_GPR_ZERO); + break; case BPF_ALU64 | BPF_MOV | BPF_X: if (insn_is_cast_user(insn)) { move_reg(ctx, t1, src); - emit_zext_32(ctx, t1, true); - move_imm(ctx, dst, (ctx->user_vm_start >> 32) << 32, false); + move_imm(ctx, dst, (ctx->user_vm_start >> 32) << 32); emit_insn(ctx, beq, t1, LOONGARCH_GPR_ZERO, 1); emit_insn(ctx, or, t1, dst, t1); move_reg(ctx, dst, t1); break; } + switch (off) { case 0: move_reg(ctx, dst, src); - emit_zext_32(ctx, dst, is32); break; case 8: emit_insn(ctx, extwb, dst, src); - emit_zext_32(ctx, dst, is32); break; case 16: emit_insn(ctx, extwh, dst, src); - emit_zext_32(ctx, dst, is32); break; case 32: emit_insn(ctx, addw, dst, src, LOONGARCH_GPR_ZERO); @@ -773,202 +761,234 @@ static int build_insn(const struct bpf_insn *insn, struct jit_ctx *ctx, bool ext /* dst = imm */ case BPF_ALU | BPF_MOV | BPF_K: case BPF_ALU64 | BPF_MOV | BPF_K: - move_imm(ctx, dst, imm, is32); + move_imm(ctx, dst, imm); break; /* dst = dst + src */ case BPF_ALU | BPF_ADD | BPF_X: + emit_insn(ctx, addw, dst, dst, src); + break; case BPF_ALU64 | BPF_ADD | BPF_X: emit_insn(ctx, addd, dst, dst, src); - emit_zext_32(ctx, dst, is32); break; /* dst = dst + imm */ case BPF_ALU | BPF_ADD | BPF_K: + if (is_signed_imm12(imm)) { + emit_insn(ctx, addiw, dst, dst, imm); + } else { + move_imm(ctx, t1, imm); + emit_insn(ctx, addw, dst, dst, t1); + } + break; case BPF_ALU64 | BPF_ADD | BPF_K: if (is_signed_imm12(imm)) { emit_insn(ctx, addid, dst, dst, imm); } else { - move_imm(ctx, t1, imm, is32); + move_imm(ctx, t1, imm); emit_insn(ctx, addd, dst, dst, t1); } - emit_zext_32(ctx, dst, is32); break; /* dst = dst - src */ case BPF_ALU | BPF_SUB | BPF_X: + emit_insn(ctx, subw, dst, dst, src); + break; case BPF_ALU64 | BPF_SUB | BPF_X: emit_insn(ctx, subd, dst, dst, src); - emit_zext_32(ctx, dst, is32); break; /* dst = dst - imm */ case BPF_ALU | BPF_SUB | BPF_K: + if (is_signed_imm12(-imm)) { + emit_insn(ctx, addiw, dst, dst, -imm); + } else { + move_imm(ctx, t1, imm); + emit_insn(ctx, subw, dst, dst, t1); + } + break; case BPF_ALU64 | BPF_SUB | BPF_K: if (is_signed_imm12(-imm)) { emit_insn(ctx, addid, dst, dst, -imm); } else { - move_imm(ctx, t1, imm, is32); + move_imm(ctx, t1, imm); emit_insn(ctx, subd, dst, dst, t1); } - emit_zext_32(ctx, dst, is32); break; /* dst = dst * src */ case BPF_ALU | BPF_MUL | BPF_X: + emit_insn(ctx, mulw, dst, dst, src); + break; case BPF_ALU64 | BPF_MUL | BPF_X: emit_insn(ctx, muld, dst, dst, src); - emit_zext_32(ctx, dst, is32); break; /* dst = dst * imm */ case BPF_ALU | BPF_MUL | BPF_K: + move_imm(ctx, t1, imm); + emit_insn(ctx, mulw, dst, dst, t1); + break; case BPF_ALU64 | BPF_MUL | BPF_K: - move_imm(ctx, t1, imm, is32); + move_imm(ctx, t1, imm); emit_insn(ctx, muld, dst, dst, t1); - emit_zext_32(ctx, dst, is32); break; /* dst = dst / src */ case BPF_ALU | BPF_DIV | BPF_X: + if (!off) + emit_insn(ctx, divwu, dst, dst, src); + else + emit_insn(ctx, divw, dst, dst, src); + break; case BPF_ALU64 | BPF_DIV | BPF_X: - if (!off) { - emit_zext_32(ctx, dst, is32); - move_reg(ctx, t1, src); - emit_zext_32(ctx, t1, is32); - emit_insn(ctx, divdu, dst, dst, t1); - emit_zext_32(ctx, dst, is32); - } else { - emit_sext_32(ctx, dst, is32); - move_reg(ctx, t1, src); - emit_sext_32(ctx, t1, is32); - emit_insn(ctx, divd, dst, dst, t1); - emit_sext_32(ctx, dst, is32); - } + if (!off) + emit_insn(ctx, divdu, dst, dst, src); + else + emit_insn(ctx, divd, dst, dst, src); break; /* dst = dst / imm */ case BPF_ALU | BPF_DIV | BPF_K: + move_imm(ctx, t1, imm); + if (!off) + emit_insn(ctx, divwu, dst, dst, t1); + else + emit_insn(ctx, divw, dst, dst, t1); + break; case BPF_ALU64 | BPF_DIV | BPF_K: - if (!off) { - move_imm(ctx, t1, imm, is32); - emit_zext_32(ctx, dst, is32); + move_imm(ctx, t1, imm); + if (!off) emit_insn(ctx, divdu, dst, dst, t1); - emit_zext_32(ctx, dst, is32); - } else { - move_imm(ctx, t1, imm, false); - emit_sext_32(ctx, t1, is32); - emit_sext_32(ctx, dst, is32); + else emit_insn(ctx, divd, dst, dst, t1); - emit_sext_32(ctx, dst, is32); - } break; /* dst = dst % src */ case BPF_ALU | BPF_MOD | BPF_X: + if (!off) + emit_insn(ctx, modwu, dst, dst, src); + else + emit_insn(ctx, modw, dst, dst, src); + break; case BPF_ALU64 | BPF_MOD | BPF_X: - if (!off) { - emit_zext_32(ctx, dst, is32); - move_reg(ctx, t1, src); - emit_zext_32(ctx, t1, is32); - emit_insn(ctx, moddu, dst, dst, t1); - emit_zext_32(ctx, dst, is32); - } else { - emit_sext_32(ctx, dst, is32); - move_reg(ctx, t1, src); - emit_sext_32(ctx, t1, is32); - emit_insn(ctx, modd, dst, dst, t1); - emit_sext_32(ctx, dst, is32); - } + if (!off) + emit_insn(ctx, moddu, dst, dst, src); + else + emit_insn(ctx, modd, dst, dst, src); break; /* dst = dst % imm */ case BPF_ALU | BPF_MOD | BPF_K: + move_imm(ctx, t1, imm); + if (!off) + emit_insn(ctx, modwu, dst, dst, t1); + else + emit_insn(ctx, modw, dst, dst, t1); + break; case BPF_ALU64 | BPF_MOD | BPF_K: - if (!off) { - move_imm(ctx, t1, imm, is32); - emit_zext_32(ctx, dst, is32); + move_imm(ctx, t1, imm); + if (!off) emit_insn(ctx, moddu, dst, dst, t1); - emit_zext_32(ctx, dst, is32); - } else { - move_imm(ctx, t1, imm, false); - emit_sext_32(ctx, t1, is32); - emit_sext_32(ctx, dst, is32); + else emit_insn(ctx, modd, dst, dst, t1); - emit_sext_32(ctx, dst, is32); - } break; /* dst = -dst */ case BPF_ALU | BPF_NEG: + emit_insn(ctx, subw, dst, LOONGARCH_GPR_ZERO, dst); + break; case BPF_ALU64 | BPF_NEG: emit_insn(ctx, subd, dst, LOONGARCH_GPR_ZERO, dst); - emit_zext_32(ctx, dst, is32); break; /* dst = dst & src */ case BPF_ALU | BPF_AND | BPF_X: + emit_insn(ctx, and, dst, dst, src); + emit_insn(ctx, addiw, dst, dst, 0); + break; case BPF_ALU64 | BPF_AND | BPF_X: emit_insn(ctx, and, dst, dst, src); - emit_zext_32(ctx, dst, is32); break; /* dst = dst & imm */ case BPF_ALU | BPF_AND | BPF_K: + if (is_unsigned_imm12(imm)) { + emit_insn(ctx, andi, dst, dst, imm); + } else { + move_imm(ctx, t1, imm); + emit_insn(ctx, and, dst, dst, t1); + } + emit_insn(ctx, addiw, dst, dst, 0); case BPF_ALU64 | BPF_AND | BPF_K: if (is_unsigned_imm12(imm)) { emit_insn(ctx, andi, dst, dst, imm); } else { - move_imm(ctx, t1, imm, is32); + move_imm(ctx, t1, imm); emit_insn(ctx, and, dst, dst, t1); } - emit_zext_32(ctx, dst, is32); break; /* dst = dst | src */ case BPF_ALU | BPF_OR | BPF_X: + emit_insn(ctx, or, dst, dst, src); + emit_insn(ctx, addiw, dst, dst, 0); + break; case BPF_ALU64 | BPF_OR | BPF_X: emit_insn(ctx, or, dst, dst, src); - emit_zext_32(ctx, dst, is32); break; /* dst = dst | imm */ case BPF_ALU | BPF_OR | BPF_K: + if (is_unsigned_imm12(imm)) { + emit_insn(ctx, ori, dst, dst, imm); + } else { + move_imm(ctx, t1, imm); + emit_insn(ctx, or, dst, dst, t1); + } + emit_insn(ctx, addiw, dst, dst, 0); + break; case BPF_ALU64 | BPF_OR | BPF_K: if (is_unsigned_imm12(imm)) { emit_insn(ctx, ori, dst, dst, imm); } else { - move_imm(ctx, t1, imm, is32); + move_imm(ctx, t1, imm); emit_insn(ctx, or, dst, dst, t1); } - emit_zext_32(ctx, dst, is32); break; /* dst = dst ^ src */ case BPF_ALU | BPF_XOR | BPF_X: + emit_insn(ctx, xor, dst, dst, src); + emit_insn(ctx, addiw, dst, dst, 0); + break; case BPF_ALU64 | BPF_XOR | BPF_X: emit_insn(ctx, xor, dst, dst, src); - emit_zext_32(ctx, dst, is32); break; /* dst = dst ^ imm */ case BPF_ALU | BPF_XOR | BPF_K: + if (is_unsigned_imm12(imm)) { + emit_insn(ctx, xori, dst, dst, imm); + } else { + move_imm(ctx, t1, imm); + emit_insn(ctx, xor, dst, dst, t1); + } + emit_insn(ctx, addiw, dst, dst, 0); + break; case BPF_ALU64 | BPF_XOR | BPF_K: if (is_unsigned_imm12(imm)) { emit_insn(ctx, xori, dst, dst, imm); } else { - move_imm(ctx, t1, imm, is32); + move_imm(ctx, t1, imm); emit_insn(ctx, xor, dst, dst, t1); } - emit_zext_32(ctx, dst, is32); break; /* dst = dst << src (logical) */ case BPF_ALU | BPF_LSH | BPF_X: emit_insn(ctx, sllw, dst, dst, src); - emit_zext_32(ctx, dst, is32); break; - case BPF_ALU64 | BPF_LSH | BPF_X: emit_insn(ctx, slld, dst, dst, src); break; @@ -976,9 +996,7 @@ static int build_insn(const struct bpf_insn *insn, struct jit_ctx *ctx, bool ext /* dst = dst << imm (logical) */ case BPF_ALU | BPF_LSH | BPF_K: emit_insn(ctx, slliw, dst, dst, imm); - emit_zext_32(ctx, dst, is32); break; - case BPF_ALU64 | BPF_LSH | BPF_K: emit_insn(ctx, sllid, dst, dst, imm); break; @@ -986,9 +1004,7 @@ static int build_insn(const struct bpf_insn *insn, struct jit_ctx *ctx, bool ext /* dst = dst >> src (logical) */ case BPF_ALU | BPF_RSH | BPF_X: emit_insn(ctx, srlw, dst, dst, src); - emit_zext_32(ctx, dst, is32); break; - case BPF_ALU64 | BPF_RSH | BPF_X: emit_insn(ctx, srld, dst, dst, src); break; @@ -996,9 +1012,7 @@ static int build_insn(const struct bpf_insn *insn, struct jit_ctx *ctx, bool ext /* dst = dst >> imm (logical) */ case BPF_ALU | BPF_RSH | BPF_K: emit_insn(ctx, srliw, dst, dst, imm); - emit_zext_32(ctx, dst, is32); break; - case BPF_ALU64 | BPF_RSH | BPF_K: emit_insn(ctx, srlid, dst, dst, imm); break; @@ -1006,9 +1020,7 @@ static int build_insn(const struct bpf_insn *insn, struct jit_ctx *ctx, bool ext /* dst = dst >> src (arithmetic) */ case BPF_ALU | BPF_ARSH | BPF_X: emit_insn(ctx, sraw, dst, dst, src); - emit_zext_32(ctx, dst, is32); break; - case BPF_ALU64 | BPF_ARSH | BPF_X: emit_insn(ctx, srad, dst, dst, src); break; @@ -1016,9 +1028,7 @@ static int build_insn(const struct bpf_insn *insn, struct jit_ctx *ctx, bool ext /* dst = dst >> imm (arithmetic) */ case BPF_ALU | BPF_ARSH | BPF_K: emit_insn(ctx, sraiw, dst, dst, imm); - emit_zext_32(ctx, dst, is32); break; - case BPF_ALU64 | BPF_ARSH | BPF_K: emit_insn(ctx, sraid, dst, dst, imm); break; @@ -1031,8 +1041,7 @@ static int build_insn(const struct bpf_insn *insn, struct jit_ctx *ctx, bool ext emit_insn(ctx, bstrpickd, dst, dst, 15, 0); break; case 32: - /* zero-extend 32 bits into 64 bits */ - emit_zext_32(ctx, dst, is32); + emit_insn(ctx, addiw, dst, dst, 0); break; case 64: /* do nothing */ @@ -1050,8 +1059,6 @@ static int build_insn(const struct bpf_insn *insn, struct jit_ctx *ctx, bool ext break; case 32: emit_insn(ctx, revb2w, dst, dst); - /* clear the upper 32 bits */ - emit_zext_32(ctx, dst, true); break; case 64: emit_insn(ctx, revbd, dst, dst); @@ -1070,6 +1077,11 @@ static int build_insn(const struct bpf_insn *insn, struct jit_ctx *ctx, bool ext case BPF_JMP | BPF_JSGE | BPF_X: case BPF_JMP | BPF_JSLT | BPF_X: case BPF_JMP | BPF_JSLE | BPF_X: + jmp_offset = bpf2la_offset(i, off, ctx); + if (emit_cond_jmp(ctx, cond, dst, src, jmp_offset) < 0) + goto toofar; + break; + case BPF_JMP32 | BPF_JEQ | BPF_X: case BPF_JMP32 | BPF_JNE | BPF_X: case BPF_JMP32 | BPF_JGT | BPF_X: @@ -1081,17 +1093,15 @@ static int build_insn(const struct bpf_insn *insn, struct jit_ctx *ctx, bool ext case BPF_JMP32 | BPF_JSLT | BPF_X: case BPF_JMP32 | BPF_JSLE | BPF_X: jmp_offset = bpf2la_offset(i, off, ctx); - move_reg(ctx, t1, dst); - move_reg(ctx, t2, src); if (is_signed_bpf_cond(BPF_OP(code))) { - emit_sext_32(ctx, t1, is32); - emit_sext_32(ctx, t2, is32); + if (emit_cond_jmp(ctx, cond, dst, src, jmp_offset) < 0) + goto toofar; } else { - emit_zext_32(ctx, t1, is32); - emit_zext_32(ctx, t2, is32); + emit_insn(ctx, bstrpickd, t1, dst, 31, 0); + emit_insn(ctx, bstrpickd, t2, src, 31, 0); + if (emit_cond_jmp(ctx, cond, t1, t2, jmp_offset) < 0) + goto toofar; } - if (emit_cond_jmp(ctx, cond, t1, t2, jmp_offset) < 0) - goto toofar; break; /* PC += off if dst cond imm */ @@ -1105,6 +1115,17 @@ static int build_insn(const struct bpf_insn *insn, struct jit_ctx *ctx, bool ext case BPF_JMP | BPF_JSGE | BPF_K: case BPF_JMP | BPF_JSLT | BPF_K: case BPF_JMP | BPF_JSLE | BPF_K: + jmp_offset = bpf2la_offset(i, off, ctx); + if (imm) { + move_imm(ctx, t1, imm); + tm = t1; + } else { + tm = LOONGARCH_GPR_ZERO; + } + + if (emit_cond_jmp(ctx, cond, dst, tm, jmp_offset) < 0) + goto toofar; + break; case BPF_JMP32 | BPF_JEQ | BPF_K: case BPF_JMP32 | BPF_JNE | BPF_K: case BPF_JMP32 | BPF_JGT | BPF_K: @@ -1117,41 +1138,55 @@ static int build_insn(const struct bpf_insn *insn, struct jit_ctx *ctx, bool ext case BPF_JMP32 | BPF_JSLE | BPF_K: jmp_offset = bpf2la_offset(i, off, ctx); if (imm) { - move_imm(ctx, t1, imm, false); + move_imm(ctx, t1, imm); tm = t1; } else { - /* If imm is 0, simply use zero register. */ tm = LOONGARCH_GPR_ZERO; } - move_reg(ctx, t2, dst); + if (is_signed_bpf_cond(BPF_OP(code))) { - emit_sext_32(ctx, tm, is32); - emit_sext_32(ctx, t2, is32); + if (emit_cond_jmp(ctx, cond, dst, tm, jmp_offset) < 0) + goto toofar; } else { - emit_zext_32(ctx, tm, is32); - emit_zext_32(ctx, t2, is32); + emit_insn(ctx, bstrpickd, t2, dst, 31, 0); + if (imm) + emit_insn(ctx, bstrpickd, t1, tm, 31, 0); + else + t1 = LOONGARCH_GPR_ZERO; + + if (emit_cond_jmp(ctx, cond, t2, t1, jmp_offset) < 0) + goto toofar; } - if (emit_cond_jmp(ctx, cond, t2, tm, jmp_offset) < 0) - goto toofar; break; /* PC += off if dst & src */ case BPF_JMP | BPF_JSET | BPF_X: + jmp_offset = bpf2la_offset(i, off, ctx); + emit_insn(ctx, and, t1, dst, src); + if (emit_cond_jmp(ctx, cond, t1, LOONGARCH_GPR_ZERO, jmp_offset) < 0) + goto toofar; + break; case BPF_JMP32 | BPF_JSET | BPF_X: jmp_offset = bpf2la_offset(i, off, ctx); emit_insn(ctx, and, t1, dst, src); - emit_zext_32(ctx, t1, is32); + emit_insn(ctx, addiw, t1, t1, 0); if (emit_cond_jmp(ctx, cond, t1, LOONGARCH_GPR_ZERO, jmp_offset) < 0) goto toofar; break; /* PC += off if dst & imm */ case BPF_JMP | BPF_JSET | BPF_K: + jmp_offset = bpf2la_offset(i, off, ctx); + move_imm(ctx, t1, imm); + emit_insn(ctx, and, t1, dst, t1); + if (emit_cond_jmp(ctx, cond, t1, LOONGARCH_GPR_ZERO, jmp_offset) < 0) + goto toofar; + break; case BPF_JMP32 | BPF_JSET | BPF_K: jmp_offset = bpf2la_offset(i, off, ctx); - move_imm(ctx, t1, imm, is32); + move_imm(ctx, t1, imm); emit_insn(ctx, and, t1, dst, t1); - emit_zext_32(ctx, t1, is32); + emit_insn(ctx, addiw, t1, t1, 0); if (emit_cond_jmp(ctx, cond, t1, LOONGARCH_GPR_ZERO, jmp_offset) < 0) goto toofar; break; @@ -1241,7 +1276,7 @@ static int build_insn(const struct bpf_insn *insn, struct jit_ctx *ctx, bool ext if (bpf_pseudo_func(insn)) move_addr(ctx, dst, imm64); else - move_imm(ctx, dst, imm64, is32); + move_imm(ctx, dst, imm64); return 1; } @@ -1282,7 +1317,7 @@ static int build_insn(const struct bpf_insn *insn, struct jit_ctx *ctx, bool ext else emit_insn(ctx, ldbu, dst, src, off); } else { - move_imm(ctx, t1, off, is32); + move_imm(ctx, t1, off); if (sign_extend) emit_insn(ctx, ldxb, dst, src, t1); else @@ -1296,7 +1331,7 @@ static int build_insn(const struct bpf_insn *insn, struct jit_ctx *ctx, bool ext else emit_insn(ctx, ldhu, dst, src, off); } else { - move_imm(ctx, t1, off, is32); + move_imm(ctx, t1, off); if (sign_extend) emit_insn(ctx, ldxh, dst, src, t1); else @@ -1310,7 +1345,7 @@ static int build_insn(const struct bpf_insn *insn, struct jit_ctx *ctx, bool ext else emit_insn(ctx, ldwu, dst, src, off); } else { - move_imm(ctx, t1, off, is32); + move_imm(ctx, t1, off); if (sign_extend) emit_insn(ctx, ldxw, dst, src, t1); else @@ -1318,7 +1353,7 @@ static int build_insn(const struct bpf_insn *insn, struct jit_ctx *ctx, bool ext } break; case BPF_DW: - move_imm(ctx, t1, off, is32); + move_imm(ctx, t1, off); emit_insn(ctx, ldxd, dst, src, t1); break; } @@ -1353,42 +1388,42 @@ static int build_insn(const struct bpf_insn *insn, struct jit_ctx *ctx, bool ext switch (BPF_SIZE(code)) { case BPF_B: - move_imm(ctx, t1, imm, is32); + move_imm(ctx, t1, imm); if (is_signed_imm12(off)) { emit_insn(ctx, stb, t1, dst, off); } else { - move_imm(ctx, t2, off, is32); + move_imm(ctx, t2, off); emit_insn(ctx, stxb, t1, dst, t2); } break; case BPF_H: - move_imm(ctx, t1, imm, is32); + move_imm(ctx, t1, imm); if (is_signed_imm12(off)) { emit_insn(ctx, sth, t1, dst, off); } else { - move_imm(ctx, t2, off, is32); + move_imm(ctx, t2, off); emit_insn(ctx, stxh, t1, dst, t2); } break; case BPF_W: - move_imm(ctx, t1, imm, is32); + move_imm(ctx, t1, imm); if (is_signed_imm12(off)) { emit_insn(ctx, stw, t1, dst, off); } else if (is_signed_imm14(off)) { emit_insn(ctx, stptrw, t1, dst, off); } else { - move_imm(ctx, t2, off, is32); + move_imm(ctx, t2, off); emit_insn(ctx, stxw, t1, dst, t2); } break; case BPF_DW: - move_imm(ctx, t1, imm, is32); + move_imm(ctx, t1, imm); if (is_signed_imm12(off)) { emit_insn(ctx, std, t1, dst, off); } else if (is_signed_imm14(off)) { emit_insn(ctx, stptrd, t1, dst, off); } else { - move_imm(ctx, t2, off, is32); + move_imm(ctx, t2, off); emit_insn(ctx, stxd, t1, dst, t2); } break; @@ -1419,7 +1454,7 @@ static int build_insn(const struct bpf_insn *insn, struct jit_ctx *ctx, bool ext if (is_signed_imm12(off)) { emit_insn(ctx, stb, src, dst, off); } else { - move_imm(ctx, t1, off, is32); + move_imm(ctx, t1, off); emit_insn(ctx, stxb, src, dst, t1); } break; @@ -1427,7 +1462,7 @@ static int build_insn(const struct bpf_insn *insn, struct jit_ctx *ctx, bool ext if (is_signed_imm12(off)) { emit_insn(ctx, sth, src, dst, off); } else { - move_imm(ctx, t1, off, is32); + move_imm(ctx, t1, off); emit_insn(ctx, stxh, src, dst, t1); } break; @@ -1437,7 +1472,7 @@ static int build_insn(const struct bpf_insn *insn, struct jit_ctx *ctx, bool ext } else if (is_signed_imm14(off)) { emit_insn(ctx, stptrw, src, dst, off); } else { - move_imm(ctx, t1, off, is32); + move_imm(ctx, t1, off); emit_insn(ctx, stxw, src, dst, t1); } break; @@ -1447,7 +1482,7 @@ static int build_insn(const struct bpf_insn *insn, struct jit_ctx *ctx, bool ext } else if (is_signed_imm14(off)) { emit_insn(ctx, stptrd, src, dst, off); } else { - move_imm(ctx, t1, off, is32); + move_imm(ctx, t1, off); emit_insn(ctx, stxd, src, dst, t1); } break; @@ -1559,7 +1594,7 @@ static int emit_jump_and_link(struct jit_ctx *ctx, u8 rd, u64 target) return -EFAULT; } - move_imm(ctx, LOONGARCH_GPR_T1, target, false); + move_imm(ctx, LOONGARCH_GPR_T1, target); emit_insn(ctx, jirl, rd, LOONGARCH_GPR_T1, 0); return 0; @@ -1733,7 +1768,7 @@ static int invoke_bpf_prog(struct jit_ctx *ctx, struct bpf_tramp_node *n, emit_insn(ctx, std, LOONGARCH_GPR_ZERO, LOONGARCH_GPR_FP, -run_ctx_off + cookie_off); /* arg1: prog */ - move_imm(ctx, LOONGARCH_GPR_A0, (const s64)p, false); + move_imm(ctx, LOONGARCH_GPR_A0, (const s64)p); /* arg2: &run_ctx */ emit_insn(ctx, addid, LOONGARCH_GPR_A1, LOONGARCH_GPR_FP, -run_ctx_off); ret = emit_call(ctx, (const u64)bpf_trampoline_enter(p)); @@ -1754,7 +1789,7 @@ static int invoke_bpf_prog(struct jit_ctx *ctx, struct bpf_tramp_node *n, /* arg1: &args_off */ emit_insn(ctx, addid, LOONGARCH_GPR_A0, LOONGARCH_GPR_FP, -args_off); if (!p->jited) - move_imm(ctx, LOONGARCH_GPR_A1, (const s64)p->insnsi, false); + move_imm(ctx, LOONGARCH_GPR_A1, (const s64)p->insnsi); ret = emit_call(ctx, (const u64)p->bpf_func); if (ret) return ret; @@ -1771,7 +1806,7 @@ static int invoke_bpf_prog(struct jit_ctx *ctx, struct bpf_tramp_node *n, } /* arg1: prog */ - move_imm(ctx, LOONGARCH_GPR_A0, (const s64)p, false); + move_imm(ctx, LOONGARCH_GPR_A0, (const s64)p); /* arg2: prog start time */ move_reg(ctx, LOONGARCH_GPR_A1, LOONGARCH_GPR_S1); /* arg3: &run_ctx */ diff --git a/arch/loongarch/net/bpf_jit.h b/arch/loongarch/net/bpf_jit.h index bb58c42c2f2a..2bd0dc5b911c 100644 --- a/arch/loongarch/net/bpf_jit.h +++ b/arch/loongarch/net/bpf_jit.h @@ -72,24 +72,6 @@ static inline int epilogue_offset(const struct jit_ctx *ctx) return (to - from); } -/* Zero-extend 32 bits into 64 bits */ -static inline void emit_zext_32(struct jit_ctx *ctx, enum loongarch_gpr reg, bool is32) -{ - if (!is32) - return; - - emit_insn(ctx, lu32id, reg, 0); -} - -/* Signed-extend 32 bits into 64 bits */ -static inline void emit_sext_32(struct jit_ctx *ctx, enum loongarch_gpr reg, bool is32) -{ - if (!is32) - return; - - emit_insn(ctx, addiw, reg, reg, 0); -} - /* Emit proper extension according to ABI requirements. * Note that it requires a value of size `size` already resides in register `reg`. */ @@ -137,7 +119,7 @@ static inline void move_addr(struct jit_ctx *ctx, enum loongarch_gpr rd, u64 add emit_insn(ctx, lu52id, rd, rd, imm_63_52); } -static inline void move_imm(struct jit_ctx *ctx, enum loongarch_gpr rd, long imm, bool is32) +static inline void move_imm(struct jit_ctx *ctx, enum loongarch_gpr rd, long imm) { long imm_11_0, imm_31_12, imm_51_32, imm_63_52, imm_51_0, imm_51_31; @@ -150,7 +132,7 @@ static inline void move_imm(struct jit_ctx *ctx, enum loongarch_gpr rd, long imm /* addiw rd, $zero, imm_11_0 */ if (is_signed_imm12(imm)) { emit_insn(ctx, addiw, rd, LOONGARCH_GPR_ZERO, imm); - goto zext; + return; } /* ori rd, $zero, imm_11_0 */ @@ -195,9 +177,6 @@ static inline void move_imm(struct jit_ctx *ctx, enum loongarch_gpr rd, long imm if (!is_signed_imm52(imm)) emit_insn(ctx, lu52id, rd, rd, imm_63_52); } - -zext: - emit_zext_32(ctx, rd, is32); } static inline void move_reg(struct jit_ctx *ctx, enum loongarch_gpr rd, -- 2.42.0