From patchwork Thu Feb 4 20:50:00 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Song Liu X-Patchwork-Id: 376728 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=-19.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, USER_AGENT_GIT autolearn=unavailable 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 58F53C433E6 for ; Thu, 4 Feb 2021 20:51:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1A55A64E24 for ; Thu, 4 Feb 2021 20:51:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230058AbhBDUvF (ORCPT ); Thu, 4 Feb 2021 15:51:05 -0500 Received: from mx0b-00082601.pphosted.com ([67.231.153.30]:16260 "EHLO mx0b-00082601.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230027AbhBDUu7 (ORCPT ); Thu, 4 Feb 2021 15:50:59 -0500 Received: from pps.filterd (m0109332.ppops.net [127.0.0.1]) by mx0a-00082601.pphosted.com (8.16.0.43/8.16.0.43) with SMTP id 114KiI3b018843 for ; Thu, 4 Feb 2021 12:50:18 -0800 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=wtfRLaxhtN/XLmbEVOfn0W2L14eyqr9QuV8fJoD1MM8=; b=KL7wr6Vpr0kaOHVC70gdGZ+1HJRGQ9uONAjW9/hsMS0pvs9k0UZTp9WSXpZZvwPonxck 1x6s9Wem4ALru6x8Rt514kxY1MOaNfb3Zro7LVaDt6xBzbfcFVhKNByhcnzGdaf21C3h oEi0qUZPGsFqkr455J2HK6JzcYtxlCOCgJ4= Received: from mail.thefacebook.com ([163.114.132.120]) by mx0a-00082601.pphosted.com with ESMTP id 36fvyd0tme-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NOT) for ; Thu, 04 Feb 2021 12:50:18 -0800 Received: from intmgw001.05.ash7.facebook.com (2620:10d:c085:208::f) by mail.thefacebook.com (2620:10d:c085:11d::4) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.1979.3; Thu, 4 Feb 2021 12:50:17 -0800 Received: by devbig006.ftw2.facebook.com (Postfix, from userid 4523) id 2344262E1750; Thu, 4 Feb 2021 12:50:14 -0800 (PST) From: Song Liu To: , , CC: , , , , Song Liu , Yonghong Song , KP Singh Subject: [PATCH v4 bpf-next 3/4] libbpf: introduce section "iter.s/" for sleepable bpf_iter program Date: Thu, 4 Feb 2021 12:50:00 -0800 Message-ID: <20210204205002.4075937-4-songliubraving@fb.com> X-Mailer: git-send-email 2.24.1 In-Reply-To: <20210204205002.4075937-1-songliubraving@fb.com> References: <20210204205002.4075937-1-songliubraving@fb.com> MIME-Version: 1.0 X-FB-Internal: Safe X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.369, 18.0.737 definitions=2021-02-04_10:2021-02-04,2021-02-04 signatures=0 X-Proofpoint-Spam-Details: rule=fb_default_notspam policy=fb_default score=0 adultscore=0 impostorscore=0 mlxscore=0 lowpriorityscore=0 malwarescore=0 bulkscore=0 priorityscore=1501 clxscore=1015 phishscore=0 spamscore=0 mlxlogscore=842 suspectscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2009150000 definitions=main-2102040128 X-FB-Internal: deliver Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Sleepable iterator program have access to helper functions like bpf_d_path. Acked-by: Yonghong Song Acked-by: KP Singh Signed-off-by: Song Liu --- tools/lib/bpf/libbpf.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index 2abbc38005684..903ccd7e93206 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -8555,6 +8555,11 @@ static const struct bpf_sec_def section_defs[] = { .expected_attach_type = BPF_TRACE_ITER, .is_attach_btf = true, .attach_fn = attach_iter), + SEC_DEF("iter.s/", TRACING, + .expected_attach_type = BPF_TRACE_ITER, + .is_attach_btf = true, + .is_sleepable = true, + .attach_fn = attach_iter), BPF_EAPROG_SEC("xdp_devmap/", BPF_PROG_TYPE_XDP, BPF_XDP_DEVMAP), BPF_EAPROG_SEC("xdp_cpumap/", BPF_PROG_TYPE_XDP, From patchwork Thu Feb 4 20:50:01 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Song Liu X-Patchwork-Id: 376727 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=-16.3 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, UNWANTED_LANGUAGE_BODY, URIBL_BLOCKED, USER_AGENT_GIT autolearn=unavailable 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 2319AC433DB for ; Thu, 4 Feb 2021 20:51:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D0B2E64E4A for ; Thu, 4 Feb 2021 20:51:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229681AbhBDUvO (ORCPT ); Thu, 4 Feb 2021 15:51:14 -0500 Received: from mx0a-00082601.pphosted.com ([67.231.145.42]:28446 "EHLO mx0a-00082601.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230038AbhBDUvB (ORCPT ); Thu, 4 Feb 2021 15:51:01 -0500 Received: from pps.filterd (m0044010.ppops.net [127.0.0.1]) by mx0a-00082601.pphosted.com (8.16.0.43/8.16.0.43) with SMTP id 114Kj3j9020300 for ; Thu, 4 Feb 2021 12:50:19 -0800 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=xWeZCllHAszWQoRGy8PuLHjqYCV4nVlHOBNGoeXXDUQ=; b=kfx1ecIw83euY/VUdfgO8HHsKtmXiaOAzbjCcef+x2bE84lGa1+ZKRt9zOJ6XwOWTlHj eSyjUcEVsh7eKkYmyvSBLXAvwAVBL73bFll1SNrG1kd8PtJu95mjucm05Vy7VP+JSJAF Kp0bpz6ilVpLlKFaYvSPdzorf878LQVytbc= Received: from mail.thefacebook.com ([163.114.132.120]) by mx0a-00082601.pphosted.com with ESMTP id 36fy55r42t-2 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NOT) for ; Thu, 04 Feb 2021 12:50:19 -0800 Received: from intmgw006.03.ash8.facebook.com (2620:10d:c085:108::4) by mail.thefacebook.com (2620:10d:c085:21d::4) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.1979.3; Thu, 4 Feb 2021 12:50:19 -0800 Received: by devbig006.ftw2.facebook.com (Postfix, from userid 4523) id 905A862E1750; Thu, 4 Feb 2021 12:50:16 -0800 (PST) From: Song Liu To: , , CC: , , , , Song Liu Subject: [PATCH v4 bpf-next 4/4] selftests/bpf: add test for bpf_iter_task_vma Date: Thu, 4 Feb 2021 12:50:01 -0800 Message-ID: <20210204205002.4075937-5-songliubraving@fb.com> X-Mailer: git-send-email 2.24.1 In-Reply-To: <20210204205002.4075937-1-songliubraving@fb.com> References: <20210204205002.4075937-1-songliubraving@fb.com> MIME-Version: 1.0 X-FB-Internal: Safe X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.369, 18.0.737 definitions=2021-02-04_10:2021-02-04,2021-02-04 signatures=0 X-Proofpoint-Spam-Details: rule=fb_default_notspam policy=fb_default score=0 impostorscore=0 mlxlogscore=999 clxscore=1015 bulkscore=0 spamscore=0 mlxscore=0 phishscore=0 lowpriorityscore=0 malwarescore=0 adultscore=0 priorityscore=1501 suspectscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2009150000 definitions=main-2102040128 X-FB-Internal: deliver Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org The test dumps information similar to /proc/pid/maps. The first line of the output is compared against the /proc file to make sure they match. Signed-off-by: Song Liu --- .../selftests/bpf/prog_tests/bpf_iter.c | 114 ++++++++++++++++-- tools/testing/selftests/bpf/progs/bpf_iter.h | 8 ++ .../selftests/bpf/progs/bpf_iter_task_vma.c | 58 +++++++++ 3 files changed, 170 insertions(+), 10 deletions(-) create mode 100644 tools/testing/selftests/bpf/progs/bpf_iter_task_vma.c diff --git a/tools/testing/selftests/bpf/prog_tests/bpf_iter.c b/tools/testing/selftests/bpf/prog_tests/bpf_iter.c index 0e586368948dd..9e8027685e859 100644 --- a/tools/testing/selftests/bpf/prog_tests/bpf_iter.c +++ b/tools/testing/selftests/bpf/prog_tests/bpf_iter.c @@ -7,6 +7,7 @@ #include "bpf_iter_task.skel.h" #include "bpf_iter_task_stack.skel.h" #include "bpf_iter_task_file.skel.h" +#include "bpf_iter_task_vma.skel.h" #include "bpf_iter_task_btf.skel.h" #include "bpf_iter_tcp4.skel.h" #include "bpf_iter_tcp6.skel.h" @@ -64,6 +65,22 @@ static void do_dummy_read(struct bpf_program *prog) bpf_link__destroy(link); } +static int read_fd_into_buffer(int fd, char *buf, int size) +{ + int bufleft = size; + int len; + + do { + len = read(fd, buf, bufleft); + if (len > 0) { + buf += len; + bufleft -= len; + } + } while (len > 0); + + return len < 0 ? len : size - bufleft; +} + static void test_ipv6_route(void) { struct bpf_iter_ipv6_route *skel; @@ -177,7 +194,7 @@ static int do_btf_read(struct bpf_iter_task_btf *skel) { struct bpf_program *prog = skel->progs.dump_task_struct; struct bpf_iter_task_btf__bss *bss = skel->bss; - int iter_fd = -1, len = 0, bufleft = TASKBUFSZ; + int iter_fd = -1, err; struct bpf_link *link; char *buf = taskbuf; int ret = 0; @@ -190,14 +207,7 @@ static int do_btf_read(struct bpf_iter_task_btf *skel) if (CHECK(iter_fd < 0, "create_iter", "create_iter failed\n")) goto free_link; - do { - len = read(iter_fd, buf, bufleft); - if (len > 0) { - buf += len; - bufleft -= len; - } - } while (len > 0); - + err = read_fd_into_buffer(iter_fd, buf, TASKBUFSZ); if (bss->skip) { printf("%s:SKIP:no __builtin_btf_type_id\n", __func__); ret = 1; @@ -205,7 +215,7 @@ static int do_btf_read(struct bpf_iter_task_btf *skel) goto free_link; } - if (CHECK(len < 0, "read", "read failed: %s\n", strerror(errno))) + if (CHECK(err < 0, "read", "read failed: %s\n", strerror(errno))) goto free_link; CHECK(strstr(taskbuf, "(struct task_struct)") == NULL, @@ -1133,6 +1143,88 @@ static void test_buf_neg_offset(void) bpf_iter_test_kern6__destroy(skel); } +#define CMP_BUFFER_SIZE 1024 +static char task_vma_output[CMP_BUFFER_SIZE]; +static char proc_maps_output[CMP_BUFFER_SIZE]; + +/* remove \0 and \t from str, and only keep the first line */ +static void str_strip_first_line(char *str) +{ + char *dst = str, *src = str; + + do { + if (*src == ' ' || *src == '\t') + src++; + else + *(dst++) = *(src++); + + } while (*src != '\0' && *src != '\n'); + + *dst = '\0'; +} + +#define min(a, b) ((a) < (b) ? (a) : (b)) + +static void test_task_vma(void) +{ + int err, iter_fd = -1, proc_maps_fd = -1; + struct bpf_iter_task_vma *skel; + int len, read_size = 4; + char maps_path[64]; + + skel = bpf_iter_task_vma__open(); + if (CHECK(!skel, "bpf_iter_task_vma__open", "skeleton open failed\n")) + return; + + skel->bss->pid = getpid(); + + err = bpf_iter_task_vma__load(skel); + if (CHECK(err, "bpf_iter_task_vma__load", "skeleton load failed\n")) + goto out; + + skel->links.proc_maps = bpf_program__attach_iter( + skel->progs.proc_maps, NULL); + + if (CHECK(IS_ERR(skel->links.proc_maps), "bpf_program__attach_iter", + "attach iterator failed\n")) + goto out; + + /* read CMP_BUFFER_SIZE (1kB) from bpf_iter */ + iter_fd = bpf_iter_create(bpf_link__fd(skel->links.proc_maps)); + if (CHECK(iter_fd < 0, "create_iter", "create_iter failed\n")) + goto out; + + /* read in small chunks to trigger seq_file corner cases */ + len = 0; + while (len < CMP_BUFFER_SIZE) { + err = read_fd_into_buffer(iter_fd, task_vma_output + len, + min(read_size, CMP_BUFFER_SIZE - len)); + if (CHECK(err < 0, "read_iter_fd", "read_iter_fd failed\n")) + goto out; + len += err; + } + + /* read CMP_BUFFER_SIZE (1kB) from /proc/pid/maps */ + snprintf(maps_path, 64, "/proc/%u/maps", skel->bss->pid); + proc_maps_fd = open(maps_path, O_RDONLY); + if (CHECK(proc_maps_fd < 0, "open_proc_maps", "open_proc_maps failed\n")) + goto out; + err = read_fd_into_buffer(proc_maps_fd, proc_maps_output, CMP_BUFFER_SIZE); + if (CHECK(err < 0, "read_prog_maps_fd", "read_prog_maps_fd failed\n")) + goto out; + + /* strip and compare the first line of the two files */ + str_strip_first_line(task_vma_output); + str_strip_first_line(proc_maps_output); + + CHECK(strcmp(task_vma_output, proc_maps_output), "compare_output", + "found mismatch\n"); +out: + close(proc_maps_fd); + close(iter_fd); + bpf_iter_task_vma__destroy(skel); +} + void test_bpf_iter(void) { if (test__start_subtest("btf_id_or_null")) @@ -1149,6 +1241,8 @@ void test_bpf_iter(void) test_task_stack(); if (test__start_subtest("task_file")) test_task_file(); + if (test__start_subtest("task_vma")) + test_task_vma(); if (test__start_subtest("task_btf")) test_task_btf(); if (test__start_subtest("tcp4")) diff --git a/tools/testing/selftests/bpf/progs/bpf_iter.h b/tools/testing/selftests/bpf/progs/bpf_iter.h index 6a1255465fd6d..3d83b185c4bcb 100644 --- a/tools/testing/selftests/bpf/progs/bpf_iter.h +++ b/tools/testing/selftests/bpf/progs/bpf_iter.h @@ -7,6 +7,7 @@ #define bpf_iter__netlink bpf_iter__netlink___not_used #define bpf_iter__task bpf_iter__task___not_used #define bpf_iter__task_file bpf_iter__task_file___not_used +#define bpf_iter__task_vma bpf_iter__task_vma___not_used #define bpf_iter__tcp bpf_iter__tcp___not_used #define tcp6_sock tcp6_sock___not_used #define bpf_iter__udp bpf_iter__udp___not_used @@ -26,6 +27,7 @@ #undef bpf_iter__netlink #undef bpf_iter__task #undef bpf_iter__task_file +#undef bpf_iter__task_vma #undef bpf_iter__tcp #undef tcp6_sock #undef bpf_iter__udp @@ -67,6 +69,12 @@ struct bpf_iter__task_file { struct file *file; } __attribute__((preserve_access_index)); +struct bpf_iter__task_vma { + struct bpf_iter_meta *meta; + struct task_struct *task; + struct vm_area_struct *vma; +} __attribute__((preserve_access_index)); + struct bpf_iter__bpf_map { struct bpf_iter_meta *meta; struct bpf_map *map; diff --git a/tools/testing/selftests/bpf/progs/bpf_iter_task_vma.c b/tools/testing/selftests/bpf/progs/bpf_iter_task_vma.c new file mode 100644 index 0000000000000..d789e32cdb16c --- /dev/null +++ b/tools/testing/selftests/bpf/progs/bpf_iter_task_vma.c @@ -0,0 +1,58 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2020 Facebook */ +#include "bpf_iter.h" +#include +#include + +char _license[] SEC("license") = "GPL"; + +/* Copied from mm.h */ +#define VM_READ 0x00000001 +#define VM_WRITE 0x00000002 +#define VM_EXEC 0x00000004 +#define VM_MAYSHARE 0x00000080 + +/* Copied from kdev_t.h */ +#define MINORBITS 20 +#define MINORMASK ((1U << MINORBITS) - 1) +#define MAJOR(dev) ((unsigned int) ((dev) >> MINORBITS)) +#define MINOR(dev) ((unsigned int) ((dev) & MINORMASK)) + +#define D_PATH_BUF_SIZE 1024 +char d_path_buf[D_PATH_BUF_SIZE] = {}; +__u32 pid = 0; + +SEC("iter.s/task_vma") int proc_maps(struct bpf_iter__task_vma *ctx) +{ + struct vm_area_struct *vma = ctx->vma; + struct seq_file *seq = ctx->meta->seq; + struct task_struct *task = ctx->task; + struct file *file; + char perm_str[] = "----"; + + if (task == (void *)0 || vma == (void *)0) + return 0; + + file = vma->vm_file; + if (task->tgid != pid) + return 0; + perm_str[0] = (vma->vm_flags & VM_READ) ? 'r' : '-'; + perm_str[1] = (vma->vm_flags & VM_WRITE) ? 'w' : '-'; + perm_str[2] = (vma->vm_flags & VM_EXEC) ? 'x' : '-'; + perm_str[3] = (vma->vm_flags & VM_MAYSHARE) ? 's' : 'p'; + BPF_SEQ_PRINTF(seq, "%08llx-%08llx %s ", vma->vm_start, vma->vm_end, perm_str); + + if (file) { + __u32 dev = file->f_inode->i_sb->s_dev; + + bpf_d_path(&file->f_path, d_path_buf, D_PATH_BUF_SIZE); + + BPF_SEQ_PRINTF(seq, "%08llx ", vma->vm_pgoff << 12); + BPF_SEQ_PRINTF(seq, "%02x:%02x %u", MAJOR(dev), MINOR(dev), + file->f_inode->i_ino); + BPF_SEQ_PRINTF(seq, "\t%s\n", d_path_buf); + } else { + BPF_SEQ_PRINTF(seq, "%08llx 00:00 0\n", 0ULL); + } + return 0; +}