From patchwork Thu Oct 8 23:39:55 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrii Nakryiko X-Patchwork-Id: 11824753 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-13.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7C68AC4363A for ; Thu, 8 Oct 2020 23:40:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2C5DF2224F for ; Thu, 8 Oct 2020 23:40:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1602200445; bh=dcH7jsOI9nC9ba8HtNCMIWG39/X0//Anft+FySEM+WA=; h=From:To:CC:Subject:Date:In-Reply-To:References:List-ID:From; b=dIy/BSLEDBDqeshsCGxSrx2FuD9kV/J+8pIYgtKm8kCxrfZnXSXMi3SiRbaXIT5FN Y8XWWy1PnB8ACAJ8kq+NR56J8ZewfbFs0u4o5hh4nBEszmLN0AhX00jda7acTR6Sio I2OmlGOmQunqBUAuM9zb2Ln7CqDdGZ+swHqQyDY0= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731066AbgJHXko convert rfc822-to-8bit (ORCPT ); Thu, 8 Oct 2020 19:40:44 -0400 Received: from mx0b-00082601.pphosted.com ([67.231.153.30]:25626 "EHLO mx0b-00082601.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731080AbgJHXko (ORCPT ); Thu, 8 Oct 2020 19:40:44 -0400 Received: from pps.filterd (m0148460.ppops.net [127.0.0.1]) by mx0a-00082601.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id 098Nefws027434 for ; Thu, 8 Oct 2020 16:40:43 -0700 Received: from maileast.thefacebook.com ([163.114.130.16]) by mx0a-00082601.pphosted.com with ESMTP id 3429ggrw6f-4 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NOT) for ; Thu, 08 Oct 2020 16:40:43 -0700 Received: from intmgw001.08.frc2.facebook.com (2620:10d:c0a8:1b::d) by mail.thefacebook.com (2620:10d:c0a8:82::e) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.1979.3; Thu, 8 Oct 2020 16:40:14 -0700 Received: by devbig012.ftw2.facebook.com (Postfix, from userid 137359) id 2936F2EC7C76; Thu, 8 Oct 2020 16:40:10 -0700 (PDT) From: Andrii Nakryiko To: CC: , , , Andrii Nakryiko , Arnaldo Carvalho de Melo , Andrii Nakryiko Subject: [PATCH v2 dwarves 3/8] btf_encoder: fix emitting __ARRAY_SIZE_TYPE__ as index range type Date: Thu, 8 Oct 2020 16:39:55 -0700 Message-ID: <20201008234000.740660-4-andrii@kernel.org> X-Mailer: git-send-email 2.24.1 In-Reply-To: <20201008234000.740660-1-andrii@kernel.org> References: <20201008234000.740660-1-andrii@kernel.org> MIME-Version: 1.0 X-FB-Internal: Safe X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.235,18.0.687 definitions=2020-10-08_15:2020-10-08,2020-10-08 signatures=0 X-Proofpoint-Spam-Details: rule=fb_default_notspam policy=fb_default score=0 mlxlogscore=999 priorityscore=1501 bulkscore=0 impostorscore=0 malwarescore=0 mlxscore=0 adultscore=0 suspectscore=15 lowpriorityscore=0 phishscore=0 spamscore=0 clxscore=1015 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2009150000 definitions=main-2010080167 X-FB-Internal: deliver Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org From: Andrii Nakryiko Fix the logic of determining if __ARRAY_SIZE_TYPE__ needs to be emitted. Previously, such type could be emitted unnecessarily due to some particular CU not having an int type in it. That would happen even if there was no array type in that CU. Fix it by keeping track of 'int' type across CUs and only emitting __ARRAY_SIZE_TYPE__ if a given CU has array type, but we still haven't found 'int' type. Testing against vmlinux shows that now there are no __ARRAY_SIZE_TYPE__ integers emitted. Signed-off-by: Andrii Nakryiko --- btf_encoder.c | 30 +++++++++++++++++++++--------- 1 file changed, 21 insertions(+), 9 deletions(-) diff --git a/btf_encoder.c b/btf_encoder.c index 6e6bce202438..2e5df03e040f 100644 --- a/btf_encoder.c +++ b/btf_encoder.c @@ -147,6 +147,8 @@ static int32_t enumeration_type__encode(struct btf_elf *btfe, struct cu *cu, str return type_id; } +static bool need_index_type; + static int tag__encode_btf(struct cu *cu, struct tag *tag, uint32_t core_id, struct btf_elf *btfe, uint32_t array_index_id, uint32_t type_id_off) { @@ -179,6 +181,7 @@ static int tag__encode_btf(struct cu *cu, struct tag *tag, uint32_t core_id, str return structure_type__encode(btfe, cu, tag, type_id_off); case DW_TAG_array_type: /* TODO: Encode one dimension at a time. */ + need_index_type = true; return btf_elf__add_array(btfe, ref_type_id, array_index_id, array_type__nelems(tag)); case DW_TAG_enumeration_type: return enumeration_type__encode(btfe, cu, tag); @@ -193,6 +196,7 @@ static int tag__encode_btf(struct cu *cu, struct tag *tag, uint32_t core_id, str static struct btf_elf *btfe; static uint32_t array_index_id; +static bool has_index_type; int btf_encoder__encode() { @@ -228,7 +232,6 @@ static struct variable *hashaddr__find_variable(const struct hlist_head hashtabl int cu__encode_btf(struct cu *cu, int verbose, bool force, bool skip_encoding_vars) { - bool add_index_type = false; uint32_t type_id_off; uint32_t core_id; struct function *fn; @@ -254,18 +257,26 @@ int cu__encode_btf(struct cu *cu, int verbose, bool force, if (!btfe) return -1; - /* cu__find_base_type_by_name() takes "type_id_t *id" */ - type_id_t id; - if (!cu__find_base_type_by_name(cu, "int", &id)) { - add_index_type = true; - id = cu->types_table.nr_entries; - } - array_index_id = id; + has_index_type = false; + need_index_type = false; + array_index_id = 0; if (verbose) printf("File %s:\n", btfe->filename); } + if (!has_index_type) { + /* cu__find_base_type_by_name() takes "type_id_t *id" */ + type_id_t id; + if (cu__find_base_type_by_name(cu, "int", &id)) { + has_index_type = true; + array_index_id = id; + } else { + has_index_type = false; + array_index_id = cu->types_table.nr_entries; + } + } + btf_elf__verbose = verbose; type_id_off = btf__get_nr_types(btfe->btf); @@ -279,12 +290,13 @@ int cu__encode_btf(struct cu *cu, int verbose, bool force, } } - if (add_index_type) { + if (need_index_type && !has_index_type) { struct base_type bt = {}; bt.name = 0; bt.bit_size = 32; btf_elf__add_base_type(btfe, &bt, "__ARRAY_SIZE_TYPE__"); + has_index_type = true; } cu__for_each_function(cu, core_id, fn) {