From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from lindbergh.monkeyblade.net (lindbergh.monkeyblade.net [23.128.96.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id CA5AA134A8 for ; Thu, 7 Sep 2023 16:18:32 +0000 (UTC) Received: from pandora.armlinux.org.uk (unknown [IPv6:2001:4d48:ad52:32c8:5054:ff:fe00:142]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BC25F59E6; Thu, 7 Sep 2023 09:18:05 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=armlinux.org.uk; s=pandora-2019; h=Sender:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=k88EuUMY0b0fVqwKK7YcLe5ATGkcAlIQr4gjeYVQGL8=; b=h0GtiSVvoU6g32+4BVLdEU6Y25 gvaqeiWdfEMR0//f+bP7UMCaUE9ZOtW7Xw7IOHS1DebWpigkZ0mXVIBVtZ2uuUcEtF/rHXbJTmu6H PtwePEmJxM/fg77yCk8JKKd4QZTl9x1C9U1DoW4HkeqVraQp+dsVoPjo77G8beVqctDXbrprc4UED 9ieWBvqQzk081qIsjPeY5+s1yXIzDqoY3SiCHtJgNm6miONTqzLO34jynit8W/fXXwosxivBLpwCm rl2a8D61Ek4PdEsdvxqXVmNnsVLT1vgU3UTf9GH+f4KTYsrtaCulGRRQQOU+ZWCjmTWFQuAMtWXC2 qgdzGMBg==; Received: from shell.armlinux.org.uk ([fd8f:7570:feb6:1:5054:ff:fe00:4ec]:42168) by pandora.armlinux.org.uk with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.96) (envelope-from ) id 1qeAgT-0001eu-2u; Thu, 07 Sep 2023 09:48:17 +0100 Received: from linux by shell.armlinux.org.uk with local (Exim 4.94.2) (envelope-from ) id 1qeAgT-0005hI-UU; Thu, 07 Sep 2023 09:48:17 +0100 Date: Thu, 7 Sep 2023 09:48:17 +0100 From: "Russell King (Oracle)" To: Puranjay Mohan Cc: Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko , Martin KaFai Lau , Song Liu , Yonghong Song , John Fastabend , KP Singh , Stanislav Fomichev , Hao Luo , Jiri Olsa , Shubham Bansal , Mykola Lysenko , Shuah Khan , bpf@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH bpf-next v2 4/8] arm32, bpf: add support for unconditional bswap instruction Message-ID: References: <20230906183320.1959008-1-puranjay12@gmail.com> <20230906183320.1959008-5-puranjay12@gmail.com> Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20230906183320.1959008-5-puranjay12@gmail.com> Sender: Russell King (Oracle) X-Spam-Status: No, score=-1.3 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_BLOCKED,RDNS_NONE, SPF_HELO_NONE,SPF_NONE autolearn=no autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net On Wed, Sep 06, 2023 at 06:33:16PM +0000, Puranjay Mohan wrote: > @@ -1633,8 +1633,10 @@ static int build_insn(const struct bpf_insn *insn, struct jit_ctx *ctx) > /* dst = htobe(dst) */ > case BPF_ALU | BPF_END | BPF_FROM_LE: > case BPF_ALU | BPF_END | BPF_FROM_BE: > + /* dst = bswap(dst) */ > + case BPF_ALU64 | BPF_END | BPF_TO_LE: > rd = arm_bpf_get_reg64(dst, tmp, ctx); > - if (BPF_SRC(code) == BPF_FROM_LE) > + if (BPF_SRC(code) == BPF_FROM_LE && BPF_CLASS(code) != BPF_ALU64) With the addition of the BPF_ALU64 case, I'm wondering why this if() is affected. If you were adding: case BPF_ALU64 | BPF_END | BPF_FROM_LE: then maybe there would be a reason, but the BPF_ALU64 | BPF_END | BPF_TO_LE case will never match even the original if() statement. -- RMK's Patch system: https://www.armlinux.org.uk/developer/patches/ FTTP is here! 80Mbps down 10Mbps up. Decent connectivity at last!