diff options
| author | Jiong Wang <jiong.wang@netronome.com> | 2018-12-05 19:52:33 +0100 |
|---|---|---|
| committer | Alexei Starovoitov <ast@kernel.org> | 2018-12-07 22:30:48 +0100 |
| commit | 84708c1386770e957347d847522a4aac22ea04dc (patch) | |
| tree | 120118beaa86d57206628a0af5ad5dfe998dfdbd /drivers/net | |
| parent | s390: bpf: implement jitting of BPF_ALU | BPF_ARSH | BPF_* (diff) | |
| download | linux-84708c1386770e957347d847522a4aac22ea04dc.tar.xz linux-84708c1386770e957347d847522a4aac22ea04dc.zip | |
nfp: bpf: implement jitting of BPF_ALU | BPF_ARSH | BPF_*
BPF_X support needs indirect shift mode, please see code comments for
details.
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Diffstat (limited to 'drivers/net')
| -rw-r--r-- | drivers/net/ethernet/netronome/nfp/bpf/jit.c | 45 |
1 files changed, 45 insertions, 0 deletions
diff --git a/drivers/net/ethernet/netronome/nfp/bpf/jit.c b/drivers/net/ethernet/netronome/nfp/bpf/jit.c index 97d33bb4d84d..662cbc21d909 100644 --- a/drivers/net/ethernet/netronome/nfp/bpf/jit.c +++ b/drivers/net/ethernet/netronome/nfp/bpf/jit.c @@ -2382,6 +2382,49 @@ static int neg_reg(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta) return 0; } +static int __ashr_imm(struct nfp_prog *nfp_prog, u8 dst, u8 shift_amt) +{ + /* Set signedness bit (MSB of result). */ + emit_alu(nfp_prog, reg_none(), reg_a(dst), ALU_OP_OR, reg_imm(0)); + emit_shf(nfp_prog, reg_both(dst), reg_none(), SHF_OP_ASHR, reg_b(dst), + SHF_SC_R_SHF, shift_amt); + wrp_immed(nfp_prog, reg_both(dst + 1), 0); + + return 0; +} + +static int ashr_reg(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta) +{ + const struct bpf_insn *insn = &meta->insn; + u64 umin, umax; + u8 dst, src; + + dst = insn->dst_reg * 2; + umin = meta->umin_src; + umax = meta->umax_src; + if (umin == umax) + return __ashr_imm(nfp_prog, dst, umin); + + src = insn->src_reg * 2; + /* NOTE: the first insn will set both indirect shift amount (source A) + * and signedness bit (MSB of result). + */ + emit_alu(nfp_prog, reg_none(), reg_a(src), ALU_OP_OR, reg_b(dst)); + emit_shf_indir(nfp_prog, reg_both(dst), reg_none(), SHF_OP_ASHR, + reg_b(dst), SHF_SC_R_SHF); + wrp_immed(nfp_prog, reg_both(dst + 1), 0); + + return 0; +} + +static int ashr_imm(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta) +{ + const struct bpf_insn *insn = &meta->insn; + u8 dst = insn->dst_reg * 2; + + return __ashr_imm(nfp_prog, dst, insn->imm); +} + static int shl_imm(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta) { const struct bpf_insn *insn = &meta->insn; @@ -3286,6 +3329,8 @@ static const instr_cb_t instr_cb[256] = { [BPF_ALU | BPF_DIV | BPF_K] = div_imm, [BPF_ALU | BPF_NEG] = neg_reg, [BPF_ALU | BPF_LSH | BPF_K] = shl_imm, + [BPF_ALU | BPF_ARSH | BPF_X] = ashr_reg, + [BPF_ALU | BPF_ARSH | BPF_K] = ashr_imm, [BPF_ALU | BPF_END | BPF_X] = end_reg32, [BPF_LD | BPF_IMM | BPF_DW] = imm_ld8, [BPF_LD | BPF_ABS | BPF_B] = data_ld1, |