From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 59C23C07E9D for ; Sat, 24 Sep 2022 00:33:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229514AbiIXAdW (ORCPT ); Fri, 23 Sep 2022 20:33:22 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40932 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231701AbiIXAdV (ORCPT ); Fri, 23 Sep 2022 20:33:21 -0400 Received: from mx0a-00082601.pphosted.com (mx0a-00082601.pphosted.com [67.231.145.42]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B7609E7C21 for ; Fri, 23 Sep 2022 17:33:20 -0700 (PDT) Received: from pps.filterd (m0109333.ppops.net [127.0.0.1]) by mx0a-00082601.pphosted.com (8.17.1.5/8.17.1.5) with ESMTP id 28NM8wDU013480 for ; Fri, 23 Sep 2022 17:33:20 -0700 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=fb.com; h=from : to : cc : subject : date : message-id : in-reply-to : references : mime-version : content-transfer-encoding : content-type; s=facebook; bh=jHY0XuK5xjPZG29nk6+Ds96ft4t8loiM36B7/6Zcv3E=; b=KGLv/hStMQfpO5oYAjD/bBptDUtYs7U6nxg4i0cFNjlJblIRsoWoF8fpR9Xv1U65qa4Y BIJxle5gexGi8/aOcqEknpHPp7CUI3CHeQ4zKkvmMUNdHXtsZSgXXWgrHw8AoL724u2A ldr3kS5BoOr6kzoiFhjzxVOw8qcGCuHVjGw= Received: from maileast.thefacebook.com ([163.114.130.16]) by mx0a-00082601.pphosted.com (PPS) with ESMTPS id 3jsb1nncd7-2 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NOT) for ; Fri, 23 Sep 2022 17:33:20 -0700 Received: from twshared15978.04.prn5.facebook.com (2620:10d:c0a8:1b::d) by mail.thefacebook.com (2620:10d:c0a8:83::5) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.31; Fri, 23 Sep 2022 17:33:18 -0700 Received: by devbig150.prn5.facebook.com (Postfix, from userid 187975) id 23D031082E416; Fri, 23 Sep 2022 17:33:13 -0700 (PDT) From: Jie Meng To: , , , CC: Jie Meng Subject: [PATCH bpf-next v2 1/2] bpf,x64: use shrx/sarx/shlx when available Date: Fri, 23 Sep 2022 17:32:10 -0700 Message-ID: <20220924003211.775483-2-jmeng@fb.com> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20220924003211.775483-1-jmeng@fb.com> References: <20220924003211.775483-1-jmeng@fb.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-FB-Internal: Safe Content-Type: text/plain X-Proofpoint-ORIG-GUID: jEjL85xLAk9F0RabNCAr7VbwAnUFCmlD X-Proofpoint-GUID: jEjL85xLAk9F0RabNCAr7VbwAnUFCmlD X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.205,Aquarius:18.0.895,Hydra:6.0.528,FMLib:17.11.122.1 definitions=2022-09-23_10,2022-09-22_02,2022-06-22_01 Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org Instead of shr/sar/shl that implicitly use %cl, emit their more flexible alternatives provided in BMI2 Signed-off-by: Jie Meng --- arch/x86/net/bpf_jit_comp.c | 53 +++++++++++++++++++++++++++++++++++++ 1 file changed, 53 insertions(+) diff --git a/arch/x86/net/bpf_jit_comp.c b/arch/x86/net/bpf_jit_comp.c index ae89f4143eb4..2227d81a5e44 100644 --- a/arch/x86/net/bpf_jit_comp.c +++ b/arch/x86/net/bpf_jit_comp.c @@ -889,6 +889,35 @@ static void emit_nops(u8 **pprog, int len) *pprog =3D prog; } =20 +static void emit_3vex(u8 **pprog, bool r, bool x, bool b, u8 m, + bool w, u8 src_reg2, bool l, u8 p) +{ + u8 *prog =3D *pprog; + u8 b0 =3D 0xc4, b1, b2; + u8 src2 =3D reg2hex[src_reg2]; + + if (is_ereg(src_reg2)) + src2 |=3D 1 << 3; + + /* + * 7 0 + * +---+---+---+---+---+---+---+---+ + * |~R |~X |~B | m | + * +---+---+---+---+---+---+---+---+ + */ + b1 =3D (!r << 7) | (!x << 6) | (!b << 5) | (m & 0x1f); + /* + * 7 0 + * +---+---+---+---+---+---+---+---+ + * | W | ~vvvv | L | pp | + * +---+---+---+---+---+---+---+---+ + */ + b2 =3D (w << 7) | ((~src2 & 0xf) << 3) | (l << 2) | (p & 3); + + EMIT3(b0, b1, b2); + *pprog =3D prog; +} + #define INSN_SZ_DIFF (((addrs[i] - addrs[i - 1]) - (prog - temp))) =20 static int do_jit(struct bpf_prog *bpf_prog, int *addrs, u8 *image, u8 *= rw_image, @@ -1135,7 +1164,31 @@ static int do_jit(struct bpf_prog *bpf_prog, int *= addrs, u8 *image, u8 *rw_image case BPF_ALU64 | BPF_LSH | BPF_X: case BPF_ALU64 | BPF_RSH | BPF_X: case BPF_ALU64 | BPF_ARSH | BPF_X: + if (boot_cpu_has(X86_FEATURE_BMI2) && src_reg !=3D BPF_REG_4) { + /* shrx/sarx/shlx dst_reg, dst_reg, src_reg */ + bool r =3D is_ereg(dst_reg); + u8 m =3D 2; /* escape code 0f38 */ + bool w =3D (BPF_CLASS(insn->code) =3D=3D BPF_ALU64); + u8 p; + + switch (BPF_OP(insn->code)) { + case BPF_LSH: + p =3D 1; /* prefix 0x66 */ + break; + case BPF_RSH: + p =3D 3; /* prefix 0xf2 */ + break; + case BPF_ARSH: + p =3D 2; /* prefix 0xf3 */ + break; + } + + emit_3vex(&prog, r, false, r, m, + w, src_reg, false, p); + EMIT2(0xf7, add_2reg(0xC0, dst_reg, dst_reg)); =20 + break; + } /* Check for bad case when dst_reg =3D=3D rcx */ if (dst_reg =3D=3D BPF_REG_4) { /* mov r11, dst_reg */ --=20 2.30.2