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Message-ID: <cea8a4c6-0614-451f-b878-4f9af62cf209@huaweicloud.com>
Date: Wed, 27 Mar 2024 15:27:31 +0800
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Subject: Re: [PATCH bpf-next v3 1/2] bpf,riscv: Implement PROBE_MEM32 pseudo
 instructions
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To: Puranjay Mohan <puranjay12@gmail.com>
References: <20240326224943.86912-1-puranjay12@gmail.com>
 <20240326224943.86912-2-puranjay12@gmail.com>
Cc: Alexei Starovoitov <ast@kernel.org>,
 Daniel Borkmann <daniel@iogearbox.net>, Andrii Nakryiko <andrii@kernel.org>,
 Martin KaFai Lau <martin.lau@linux.dev>, Eduard Zingerman
 <eddyz87@gmail.com>, Song Liu <song@kernel.org>,
 Yonghong Song <yonghong.song@linux.dev>,
 John Fastabend <john.fastabend@gmail.com>, KP Singh <kpsingh@kernel.org>,
 Stanislav Fomichev <sdf@google.com>, Hao Luo <haoluo@google.com>,
 Jiri Olsa <jolsa@kernel.org>, =?UTF-8?B?QmrDtnJuIFTDtnBlbA==?=
 <bjorn@kernel.org>, Luke Nelson <luke.r.nels@gmail.com>,
 Xi Wang <xi.wang@gmail.com>, Paul Walmsley <paul.walmsley@sifive.com>,
 Palmer Dabbelt <palmer@dabbelt.com>, Albert Ou <aou@eecs.berkeley.edu>,
 bpf@vger.kernel.org, linux-riscv@lists.infradead.org,
 linux-kernel@vger.kernel.org
From: Pu Lehui <pulehui@huaweicloud.com>
In-Reply-To: <20240326224943.86912-2-puranjay12@gmail.com>
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On 2024/3/27 6:49, Puranjay Mohan wrote:
> Add support for [LDX | STX | ST], PROBE_MEM32, [B | H | W | DW]
[SNIP]
>   	if (WARN_ON_ONCE(ctx->nexentries >= ctx->prog->aux->num_exentries))
> @@ -1539,6 +1547,11 @@ int bpf_jit_emit_insn(const struct bpf_insn *insn, struct rv_jit_context *ctx,
>   	case BPF_LDX | BPF_PROBE_MEMSX | BPF_B:
>   	case BPF_LDX | BPF_PROBE_MEMSX | BPF_H:
>   	case BPF_LDX | BPF_PROBE_MEMSX | BPF_W:
> +	/* LDX | PROBE_MEM32: dst = *(unsigned size *)(src + S7 + off)*/

still some nits. please align, change S7 here to reg_arena.

> +	case BPF_LDX | BPF_PROBE_MEM32 | BPF_B:
> +	case BPF_LDX | BPF_PROBE_MEM32 | BPF_H:
> +	case BPF_LDX | BPF_PROBE_MEM32 | BPF_W:
> +	case BPF_LDX | BPF_PROBE_MEM32 | BPF_DW:
[SNIP]
> +
> +		switch (BPF_SIZE(code)) {
> +		case BPF_B:
> +			if (is_12b_int(off)) {
> +				insns_start = ctx->ninsns;
> +				emit(rv_sb(rd, off, RV_REG_T1), ctx);
> +				insn_len = ctx->ninsns - insns_start;
> +				break;
> +			}
> +
> +			emit_imm(RV_REG_T2, off, ctx);
> +			emit_add(RV_REG_T2, RV_REG_T2, rd, ctx);
> +			insns_start = ctx->ninsns;
> +			emit(rv_sb(RV_REG_T2, 0, RV_REG_T1), ctx);
> +			insn_len = ctx->ninsns - insns_start;
> +
redundant blank.
> +			break;
> +
ditto.

Others, looks good to me.

Reviewed-by: Pu Lehui <pulehui@huawei.com>
Tested-by: Pu Lehui <pulehui@huawei.com>