From patchwork Fri Aug 5 21:48:20 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hao Luo X-Patchwork-Id: 12937715 X-Patchwork-Delegate: bpf@iogearbox.net 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 11720C00140 for ; Fri, 5 Aug 2022 21:50:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241617AbiHEVt7 (ORCPT ); Fri, 5 Aug 2022 17:49:59 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37762 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S241428AbiHEVtX (ORCPT ); Fri, 5 Aug 2022 17:49:23 -0400 Received: from mail-yw1-x1149.google.com (mail-yw1-x1149.google.com [IPv6:2607:f8b0:4864:20::1149]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 995027C19B for ; Fri, 5 Aug 2022 14:49:10 -0700 (PDT) Received: by mail-yw1-x1149.google.com with SMTP id 00721157ae682-324966c28e5so31304957b3.3 for ; Fri, 05 Aug 2022 14:49:10 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=cc:to:from:subject:references:mime-version:message-id:in-reply-to :date:from:to:cc; bh=60VOTA1pgsN2983c233coUD+C6cWIOV0N1M/mLyCmZk=; b=j4fPBFrpsGeMm9iuTuCFlMryx8B+8svFJu1iaOPZTemt0h0OVzPzfBzHC1j3O5eiC+ 0jd+szNOpupqyBIpdeyZ62PO/DrLEleiDm+eA258dDQqdZ7hEHUDnnheQjWSoU84ewbY tcqbNM6/kt7FBStyBPsVjCOr9jNj/8LNJrmAgxIcIbSJO/RwuWMctJ6s9YEv14j6pHuX QAlqEo5KJV5BOxtwfMHHdr2uyjWAbPgyf44IofZKSSVuMjxmrecndwqROgyjREUnwatL c3Lk7IfLClpfzydAJvCanOHQnlX1T5W4MrbuPGnOiunDNJSKMf1n5nvU6+R9q+5s7WhM RD3w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=cc:to:from:subject:references:mime-version:message-id:in-reply-to :date:x-gm-message-state:from:to:cc; bh=60VOTA1pgsN2983c233coUD+C6cWIOV0N1M/mLyCmZk=; b=FjIfoMkYQ4EmyJh+T0SGZjsf0qrP97rTP4KHplTIecRTGW3grlbJ7gGL499VhmvVVB aLs/vKBED4AZ9iDqlCBOd11R31Nsi+QFqSPf3pXCq97alI1P7QP/Qoui+SQu2ND5Sob5 uKXfGfXJFppLDmfT4nEKAyAykC07CkeZopNBNwoKNzvUhdMXD0RaYfo4kHiu+UQ+SRmZ aBWlLexJAYNgJvhcd/+i1Q5f/okXRk5nyXv4H0iLcWoM0W9hKhzPZlc1NxT9DpP4hGVg E69sUb0hqZliHqZ8oY3gl1jbqJBz384YRwGUxpk7UhqNi281ygWnPnlgitoeChJGNFfY 0sOg== X-Gm-Message-State: ACgBeo3bPHiQQOj6frb0JfbP+xcfi1HSWvkMBxq6Z2LZi8hcgBTrisib d6RASJQY8j8IUCd7MalKLxANTgq67+w= X-Google-Smtp-Source: AA6agR4VQAve8A/46IOBY8uKGmXsN0xDmlrBz01Q755cNXlDY6edzREojLgv1UtqrImz1B100/yfGsFvtZM= X-Received: from haoluo.svl.corp.google.com ([2620:15c:2d4:203:4f27:97db:8644:dc82]) (user=haoluo job=sendgmr) by 2002:a81:892:0:b0:329:28c6:6c35 with SMTP id 140-20020a810892000000b0032928c66c35mr7232234ywi.382.1659736149856; Fri, 05 Aug 2022 14:49:09 -0700 (PDT) Date: Fri, 5 Aug 2022 14:48:20 -0700 In-Reply-To: <20220805214821.1058337-1-haoluo@google.com> Message-Id: <20220805214821.1058337-8-haoluo@google.com> Mime-Version: 1.0 References: <20220805214821.1058337-1-haoluo@google.com> X-Mailer: git-send-email 2.37.1.559.g78731f0fdb-goog Subject: [PATCH bpf-next v7 7/8] selftests/bpf: extend cgroup helpers From: Hao Luo To: linux-kernel@vger.kernel.org, bpf@vger.kernel.org, cgroups@vger.kernel.org, netdev@vger.kernel.org Cc: Alexei Starovoitov , Andrii Nakryiko , Daniel Borkmann , Martin KaFai Lau , Song Liu , Yonghong Song , Tejun Heo , Zefan Li , KP Singh , Johannes Weiner , Michal Hocko , Benjamin Tissoires , John Fastabend , Michal Koutny , Roman Gushchin , David Rientjes , Stanislav Fomichev , Shakeel Butt , Yosry Ahmed , Hao Luo Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: bpf@iogearbox.net From: Yosry Ahmed This patch extends bpf selft cgroup_helpers [ID] n various ways: - Add enable_controllers() that allows tests to enable all or a subset of controllers for a specific cgroup. - Add join_cgroup_parent(). The cgroup workdir is based on the pid, therefore a spawned child cannot join the same cgroup hierarchy of the test through join_cgroup(). join_cgroup_parent() is used in child processes to join a cgroup under the parent's workdir. - Add write_cgroup_file() and write_cgroup_file_parent() (similar to join_cgroup_parent() above). - Add get_root_cgroup() for tests that need to do checks on root cgroup. - Distinguish relative and absolute cgroup paths in function arguments. Now relative paths are called relative_path, and absolute paths are called cgroup_path. Signed-off-by: Yosry Ahmed Signed-off-by: Hao Luo --- tools/testing/selftests/bpf/cgroup_helpers.c | 202 +++++++++++++++---- tools/testing/selftests/bpf/cgroup_helpers.h | 19 +- 2 files changed, 174 insertions(+), 47 deletions(-) diff --git a/tools/testing/selftests/bpf/cgroup_helpers.c b/tools/testing/selftests/bpf/cgroup_helpers.c index 9d59c3990ca8..e914cc45b766 100644 --- a/tools/testing/selftests/bpf/cgroup_helpers.c +++ b/tools/testing/selftests/bpf/cgroup_helpers.c @@ -33,49 +33,52 @@ #define CGROUP_MOUNT_DFLT "/sys/fs/cgroup" #define NETCLS_MOUNT_PATH CGROUP_MOUNT_DFLT "/net_cls" #define CGROUP_WORK_DIR "/cgroup-test-work-dir" -#define format_cgroup_path(buf, path) \ + +#define format_cgroup_path_pid(buf, path, pid) \ snprintf(buf, sizeof(buf), "%s%s%d%s", CGROUP_MOUNT_PATH, \ - CGROUP_WORK_DIR, getpid(), path) + CGROUP_WORK_DIR, pid, path) + +#define format_cgroup_path(buf, path) \ + format_cgroup_path_pid(buf, path, getpid()) + +#define format_parent_cgroup_path(buf, path) \ + format_cgroup_path_pid(buf, path, getppid()) #define format_classid_path(buf) \ snprintf(buf, sizeof(buf), "%s%s", NETCLS_MOUNT_PATH, \ CGROUP_WORK_DIR) -/** - * enable_all_controllers() - Enable all available cgroup v2 controllers - * - * Enable all available cgroup v2 controllers in order to increase - * the code coverage. - * - * If successful, 0 is returned. - */ -static int enable_all_controllers(char *cgroup_path) +static int __enable_controllers(const char *cgroup_path, const char *controllers) { char path[PATH_MAX + 1]; - char buf[PATH_MAX]; + char enable[PATH_MAX + 1]; char *c, *c2; int fd, cfd; ssize_t len; - snprintf(path, sizeof(path), "%s/cgroup.controllers", cgroup_path); - fd = open(path, O_RDONLY); - if (fd < 0) { - log_err("Opening cgroup.controllers: %s", path); - return 1; - } - - len = read(fd, buf, sizeof(buf) - 1); - if (len < 0) { + /* If not controllers are passed, enable all available controllers */ + if (!controllers) { + snprintf(path, sizeof(path), "%s/cgroup.controllers", + cgroup_path); + fd = open(path, O_RDONLY); + if (fd < 0) { + log_err("Opening cgroup.controllers: %s", path); + return 1; + } + len = read(fd, enable, sizeof(enable) - 1); + if (len < 0) { + close(fd); + log_err("Reading cgroup.controllers: %s", path); + return 1; + } else if (len == 0) { /* No controllers to enable */ + close(fd); + return 0; + } + enable[len] = 0; close(fd); - log_err("Reading cgroup.controllers: %s", path); - return 1; + } else { + strncpy(enable, controllers, sizeof(enable)); } - buf[len] = 0; - close(fd); - - /* No controllers available? We're probably on cgroup v1. */ - if (len == 0) - return 0; snprintf(path, sizeof(path), "%s/cgroup.subtree_control", cgroup_path); cfd = open(path, O_RDWR); @@ -84,7 +87,7 @@ static int enable_all_controllers(char *cgroup_path) return 1; } - for (c = strtok_r(buf, " ", &c2); c; c = strtok_r(NULL, " ", &c2)) { + for (c = strtok_r(enable, " ", &c2); c; c = strtok_r(NULL, " ", &c2)) { if (dprintf(cfd, "+%s\n", c) <= 0) { log_err("Enabling controller %s: %s", c, path); close(cfd); @@ -95,6 +98,87 @@ static int enable_all_controllers(char *cgroup_path) return 0; } +/** + * enable_controllers() - Enable cgroup v2 controllers + * @relative_path: The cgroup path, relative to the workdir + * @controllers: List of controllers to enable in cgroup.controllers format + * + * + * Enable given cgroup v2 controllers, if @controllers is NULL, enable all + * available controllers. + * + * If successful, 0 is returned. + */ +int enable_controllers(const char *relative_path, const char *controllers) +{ + char cgroup_path[PATH_MAX + 1]; + + format_cgroup_path(cgroup_path, relative_path); + return __enable_controllers(cgroup_path, controllers); +} + +static int __write_cgroup_file(const char *cgroup_path, const char *file, + const char *buf) +{ + char file_path[PATH_MAX + 1]; + int fd; + + snprintf(file_path, sizeof(file_path), "%s/%s", cgroup_path, file); + fd = open(file_path, O_RDWR); + if (fd < 0) { + log_err("Opening %s", file_path); + return 1; + } + + if (dprintf(fd, "%s", buf) <= 0) { + log_err("Writing to %s", file_path); + close(fd); + return 1; + } + close(fd); + return 0; +} + +/** + * write_cgroup_file() - Write to a cgroup file + * @relative_path: The cgroup path, relative to the workdir + * @file: The name of the file in cgroupfs to write to + * @buf: Buffer to write to the file + * + * Write to a file in the given cgroup's directory. + * + * If successful, 0 is returned. + */ +int write_cgroup_file(const char *relative_path, const char *file, + const char *buf) +{ + char cgroup_path[PATH_MAX - 24]; + + format_cgroup_path(cgroup_path, relative_path); + return __write_cgroup_file(cgroup_path, file, buf); +} + +/** + * write_cgroup_file_parent() - Write to a cgroup file in the parent process + * workdir + * @relative_path: The cgroup path, relative to the parent process workdir + * @file: The name of the file in cgroupfs to write to + * @buf: Buffer to write to the file + * + * Write to a file in the given cgroup's directory under the parent process + * workdir. + * + * If successful, 0 is returned. + */ +int write_cgroup_file_parent(const char *relative_path, const char *file, + const char *buf) +{ + char cgroup_path[PATH_MAX - 24]; + + format_parent_cgroup_path(cgroup_path, relative_path); + return __write_cgroup_file(cgroup_path, file, buf); +} + /** * setup_cgroup_environment() - Setup the cgroup environment * @@ -133,7 +217,9 @@ int setup_cgroup_environment(void) return 1; } - if (enable_all_controllers(cgroup_workdir)) + /* Enable all available controllers to increase test coverage */ + if (__enable_controllers(CGROUP_MOUNT_PATH, NULL) || + __enable_controllers(cgroup_workdir, NULL)) return 1; return 0; @@ -173,7 +259,7 @@ static int join_cgroup_from_top(const char *cgroup_path) /** * join_cgroup() - Join a cgroup - * @path: The cgroup path, relative to the workdir, to join + * @relative_path: The cgroup path, relative to the workdir, to join * * This function expects a cgroup to already be created, relative to the cgroup * work dir, and it joins it. For example, passing "/my-cgroup" as the path @@ -182,11 +268,27 @@ static int join_cgroup_from_top(const char *cgroup_path) * * On success, it returns 0, otherwise on failure it returns 1. */ -int join_cgroup(const char *path) +int join_cgroup(const char *relative_path) +{ + char cgroup_path[PATH_MAX + 1]; + + format_cgroup_path(cgroup_path, relative_path); + return join_cgroup_from_top(cgroup_path); +} + +/** + * join_parent_cgroup() - Join a cgroup in the parent process workdir + * @relative_path: The cgroup path, relative to parent process workdir, to join + * + * See join_cgroup(). + * + * On success, it returns 0, otherwise on failure it returns 1. + */ +int join_parent_cgroup(const char *relative_path) { char cgroup_path[PATH_MAX + 1]; - format_cgroup_path(cgroup_path, path); + format_parent_cgroup_path(cgroup_path, relative_path); return join_cgroup_from_top(cgroup_path); } @@ -212,9 +314,27 @@ void cleanup_cgroup_environment(void) nftw(cgroup_workdir, nftwfunc, WALK_FD_LIMIT, FTW_DEPTH | FTW_MOUNT); } +/** + * get_root_cgroup() - Get the FD of the root cgroup + * + * On success, it returns the file descriptor. On failure, it returns -1. + * If there is a failure, it prints the error to stderr. + */ +int get_root_cgroup(void) +{ + int fd; + + fd = open(CGROUP_MOUNT_PATH, O_RDONLY); + if (fd < 0) { + log_err("Opening root cgroup"); + return -1; + } + return fd; +} + /** * create_and_get_cgroup() - Create a cgroup, relative to workdir, and get the FD - * @path: The cgroup path, relative to the workdir, to join + * @relative_path: The cgroup path, relative to the workdir, to join * * This function creates a cgroup under the top level workdir and returns the * file descriptor. It is idempotent. @@ -222,14 +342,14 @@ void cleanup_cgroup_environment(void) * On success, it returns the file descriptor. On failure it returns -1. * If there is a failure, it prints the error to stderr. */ -int create_and_get_cgroup(const char *path) +int create_and_get_cgroup(const char *relative_path) { char cgroup_path[PATH_MAX + 1]; int fd; - format_cgroup_path(cgroup_path, path); + format_cgroup_path(cgroup_path, relative_path); if (mkdir(cgroup_path, 0777) && errno != EEXIST) { - log_err("mkdiring cgroup %s .. %s", path, cgroup_path); + log_err("mkdiring cgroup %s .. %s", relative_path, cgroup_path); return -1; } @@ -244,13 +364,13 @@ int create_and_get_cgroup(const char *path) /** * get_cgroup_id() - Get cgroup id for a particular cgroup path - * @path: The cgroup path, relative to the workdir, to join + * @relative_path: The cgroup path, relative to the workdir, to join * * On success, it returns the cgroup id. On failure it returns 0, * which is an invalid cgroup id. * If there is a failure, it prints the error to stderr. */ -unsigned long long get_cgroup_id(const char *path) +unsigned long long get_cgroup_id(const char *relative_path) { int dirfd, err, flags, mount_id, fhsize; union { @@ -261,7 +381,7 @@ unsigned long long get_cgroup_id(const char *path) struct file_handle *fhp, *fhp2; unsigned long long ret = 0; - format_cgroup_path(cgroup_workdir, path); + format_cgroup_path(cgroup_workdir, relative_path); dirfd = AT_FDCWD; flags = 0; diff --git a/tools/testing/selftests/bpf/cgroup_helpers.h b/tools/testing/selftests/bpf/cgroup_helpers.h index fcc9cb91b211..3358734356ab 100644 --- a/tools/testing/selftests/bpf/cgroup_helpers.h +++ b/tools/testing/selftests/bpf/cgroup_helpers.h @@ -10,11 +10,18 @@ __FILE__, __LINE__, clean_errno(), ##__VA_ARGS__) /* cgroupv2 related */ -int cgroup_setup_and_join(const char *path); -int create_and_get_cgroup(const char *path); -unsigned long long get_cgroup_id(const char *path); - -int join_cgroup(const char *path); +int enable_controllers(const char *relative_path, const char *controllers); +int write_cgroup_file(const char *relative_path, const char *file, + const char *buf); +int write_cgroup_file_parent(const char *relative_path, const char *file, + const char *buf); +int cgroup_setup_and_join(const char *relative_path); +int get_root_cgroup(void); +int create_and_get_cgroup(const char *relative_path); +unsigned long long get_cgroup_id(const char *relative_path); + +int join_cgroup(const char *relative_path); +int join_parent_cgroup(const char *relative_path); int setup_cgroup_environment(void); void cleanup_cgroup_environment(void); @@ -26,4 +33,4 @@ int join_classid(void); int setup_classid_environment(void); void cleanup_classid_environment(void); -#endif /* __CGROUP_HELPERS_H */ \ No newline at end of file +#endif /* __CGROUP_HELPERS_H */