From patchwork Sat Jan 19 18:06:56 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jakub Kicinski X-Patchwork-Id: 1028003 X-Patchwork-Delegate: bpf@iogearbox.net Return-Path: X-Original-To: patchwork-incoming-netdev@ozlabs.org Delivered-To: patchwork-incoming-netdev@ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=netdev-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=netronome.com Authentication-Results: ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=netronome-com.20150623.gappssmtp.com header.i=@netronome-com.20150623.gappssmtp.com header.b="k+ksciwN"; dkim-atps=neutral Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 43hm4T70gwz9sDn for ; Sun, 20 Jan 2019 05:07:37 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729107AbfASSHg (ORCPT ); Sat, 19 Jan 2019 13:07:36 -0500 Received: from mail-qt1-f193.google.com ([209.85.160.193]:44394 "EHLO mail-qt1-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729060AbfASSHa (ORCPT ); Sat, 19 Jan 2019 13:07:30 -0500 Received: by mail-qt1-f193.google.com with SMTP id n32so18770990qte.11 for ; Sat, 19 Jan 2019 10:07:30 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=netronome-com.20150623.gappssmtp.com; s=20150623; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=1Z1TS2RUMgtRfNBvs/oRkXHlXOMpPmew3MWWNqzkUX4=; b=k+ksciwN1hxhgG7jZ7DjwOV3rFlfnh5sCfrZ12oa7+iKS7HkXD4niYqvVCF6WhBBiE T2CozvXZ8OyPb3t1pZG5OWtj+J3XjbrgUNnD4SJiJ0RrF6ymFzyngL+nMKNzOjlL4l4x 6022KlQMqVlb4WWxxpnTBEwEv3cz/mxwsADuFnrrRLhK6LGUlRxfaQZeI2ovUsQVl4Z/ /7hHQg+MXePm2DexRDg4Sx+nrjyNXUKigj853UgVkk3sXrcJKsRoHlXlMuTqJm9uty7f gvQ306f6QlseGrgWWvxsfrBri/jQrDuuppsV8W9j59/g7PIDuDCj+9S2m1ZYppozSn1e hypQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=1Z1TS2RUMgtRfNBvs/oRkXHlXOMpPmew3MWWNqzkUX4=; b=Oo/Xp/BdO9Ig9m5tUKAVUn3CbG3BMfGgmDAtLAoGrHt6T6cG4N4SmXtKY19TqaXS3Q hINNAzaM4jN1jcRZwUafZO952KiP2+qEwWCQpcwuuJqJ0hq89zKW198Zv131Z9VTeIAW eU1gTMjLbqCvtAhRk3IsHPJtzEJZDFz2jAgnah1N8hj0MgVfcAbHL6Y3yiTLpj9u+FjA qJc/CEqQ2DmYDOJt4ffhIETBHwhvXb6WbANEVIUd2/5K2Elnu5kJFdZD6Up5IyRn53Gv x+v+KFFITE6LiW6t7EnNgp5kdBu1aSHOWNNaNcTEj3HkKMJ0FQiGz0hm5ivfIRN1ZjKd aJLw== X-Gm-Message-State: AJcUukexGiyI+dGxCZY64NEO+hshE6jrZtE0ae7iNkKYxMwReOBAR8AJ q2Z7tC/C7y1D2VnchA2Fyjzkhg== X-Google-Smtp-Source: ALg8bN7CIgFilrK46SPQ4X+tKqTDmOLCzVncQvGGVOLXB/HRufhThxSh0rp9befi8t3E5mflSGmeEQ== X-Received: by 2002:aed:29a6:: with SMTP id o35mr20175075qtd.257.1547921249628; Sat, 19 Jan 2019 10:07:29 -0800 (PST) Received: from jkicinski-Precision-T1700.netronome.com ([66.60.152.14]) by smtp.gmail.com with ESMTPSA id v2sm46521518qte.75.2019.01.19.10.07.28 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Sat, 19 Jan 2019 10:07:29 -0800 (PST) From: Jakub Kicinski To: alexei.starovoitov@gmail.com, daniel@iogearbox.net Cc: netdev@vger.kernel.org, oss-drivers@netronome.com, yhs@fb.com, Jakub Kicinski Subject: [PATCH bpf-next v5 12/12] nfp: bpf: support removing dead code Date: Sat, 19 Jan 2019 10:06:56 -0800 Message-Id: <20190119180656.24635-13-jakub.kicinski@netronome.com> X-Mailer: git-send-email 2.19.2 In-Reply-To: <20190119180656.24635-1-jakub.kicinski@netronome.com> References: <20190119180656.24635-1-jakub.kicinski@netronome.com> MIME-Version: 1.0 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Add a verifier callback to the nfp JIT to remove the instructions the verifier deemed to be dead. Signed-off-by: Jakub Kicinski Reviewed-by: Quentin Monnet --- drivers/net/ethernet/netronome/nfp/bpf/main.h | 6 ++++- .../net/ethernet/netronome/nfp/bpf/offload.c | 5 ++++ .../net/ethernet/netronome/nfp/bpf/verifier.c | 24 +++++++++++++++++++ 3 files changed, 34 insertions(+), 1 deletion(-) diff --git a/drivers/net/ethernet/netronome/nfp/bpf/main.h b/drivers/net/ethernet/netronome/nfp/bpf/main.h index a33aa7df1979..5813c3e13ebe 100644 --- a/drivers/net/ethernet/netronome/nfp/bpf/main.h +++ b/drivers/net/ethernet/netronome/nfp/bpf/main.h @@ -247,9 +247,12 @@ struct nfp_bpf_reg_state { #define FLAG_INSN_SKIP_NOOP BIT(3) /* Instruction is optimized out based on preceding instructions */ #define FLAG_INSN_SKIP_PREC_DEPENDENT BIT(4) +/* Instruction is optimized by the verifier */ +#define FLAG_INSN_SKIP_VERIFIER_OPT BIT(5) #define FLAG_INSN_SKIP_MASK (FLAG_INSN_SKIP_NOOP | \ - FLAG_INSN_SKIP_PREC_DEPENDENT) + FLAG_INSN_SKIP_PREC_DEPENDENT | \ + FLAG_INSN_SKIP_VERIFIER_OPT) /** * struct nfp_insn_meta - BPF instruction wrapper @@ -533,6 +536,7 @@ int nfp_bpf_finalize(struct bpf_verifier_env *env); int nfp_bpf_opt_replace_insn(struct bpf_verifier_env *env, u32 off, struct bpf_insn *insn); +int nfp_bpf_opt_remove_insns(struct bpf_verifier_env *env, u32 off, u32 cnt); extern const struct bpf_prog_offload_ops nfp_bpf_dev_ops; diff --git a/drivers/net/ethernet/netronome/nfp/bpf/offload.c b/drivers/net/ethernet/netronome/nfp/bpf/offload.c index 877c1b8f95e2..55c7dbf8b421 100644 --- a/drivers/net/ethernet/netronome/nfp/bpf/offload.c +++ b/drivers/net/ethernet/netronome/nfp/bpf/offload.c @@ -220,6 +220,10 @@ static int nfp_bpf_translate(struct bpf_prog *prog) unsigned int max_instr; int err; + /* We depend on dead code elimination succeeding */ + if (prog->aux->offload->opt_failed) + return -EINVAL; + max_instr = nn_readw(nn, NFP_NET_CFG_BPF_MAX_LEN); nfp_prog->__prog_alloc_len = max_instr * sizeof(u64); @@ -593,6 +597,7 @@ const struct bpf_prog_offload_ops nfp_bpf_dev_ops = { .insn_hook = nfp_verify_insn, .finalize = nfp_bpf_finalize, .replace_insn = nfp_bpf_opt_replace_insn, + .remove_insns = nfp_bpf_opt_remove_insns, .prepare = nfp_bpf_verifier_prep, .translate = nfp_bpf_translate, .destroy = nfp_bpf_destroy, diff --git a/drivers/net/ethernet/netronome/nfp/bpf/verifier.c b/drivers/net/ethernet/netronome/nfp/bpf/verifier.c index 32468e1b1b73..36f56eb4cbe2 100644 --- a/drivers/net/ethernet/netronome/nfp/bpf/verifier.c +++ b/drivers/net/ethernet/netronome/nfp/bpf/verifier.c @@ -820,3 +820,27 @@ int nfp_bpf_opt_replace_insn(struct bpf_verifier_env *env, u32 off, meta->insn.code, insn->code); return -EINVAL; } + +int nfp_bpf_opt_remove_insns(struct bpf_verifier_env *env, u32 off, u32 cnt) +{ + struct nfp_prog *nfp_prog = env->prog->aux->offload->dev_priv; + struct bpf_insn_aux_data *aux_data = env->insn_aux_data; + struct nfp_insn_meta *meta = nfp_prog->verifier_meta; + unsigned int i; + + meta = nfp_bpf_goto_meta(nfp_prog, meta, aux_data[off].orig_idx); + + for (i = 0; i < cnt; i++) { + if (WARN_ON_ONCE(&meta->l == &nfp_prog->insns)) + return -EINVAL; + + /* doesn't count if it already has the flag */ + if (meta->flags & FLAG_INSN_SKIP_VERIFIER_OPT) + i--; + + meta->flags |= FLAG_INSN_SKIP_VERIFIER_OPT; + meta = list_next_entry(meta, l); + } + + return 0; +}