From patchwork Fri May 20 01:21:32 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yosry Ahmed X-Patchwork-Id: 12856178 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 039C3C433FE for ; Fri, 20 May 2022 01:22:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1344507AbiETBWB (ORCPT ); Thu, 19 May 2022 21:22:01 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56532 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1344438AbiETBVv (ORCPT ); Thu, 19 May 2022 21:21:51 -0400 Received: from mail-pl1-x649.google.com (mail-pl1-x649.google.com [IPv6:2607:f8b0:4864:20::649]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 98BC32AC7B for ; Thu, 19 May 2022 18:21:45 -0700 (PDT) Received: by mail-pl1-x649.google.com with SMTP id e4-20020a17090301c400b00161995eef69so3347525plh.12 for ; Thu, 19 May 2022 18:21:45 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=7NpPrNa+Bz8HzFusX9ojwAjuFv1Lhyxt4v6rFhund+w=; b=eyJXXtPEk+d/1DG1nBhGcV5radE6gV+k7cAc+PXed5M9Isz+fiheznJqdqKz3LjFHX gjM+Zn3y0to7/5yaXKUwMITmClHfNHUeq5DgOPdMhXNDtJJmwtr7N9hsm4P+AxE/33PR 47mR9OLgu0ceS0+ARA7BecenYLC8hs045MtHkg9GFxYvSmco561MCjFAYvLnF7IhohsA 8kg4FfciGF4nSuxGXH2hxIDElmH0NiFTH8lZehsvuGf2jkfiz7oVxW62Xd3oI1uMTNSY M0V3bIBznmQZQX1RFieoj/ZlkXCMWREM14yxVtLxB9AVL4IMLgE955H+TfzjNt2vNZVS IVRA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=7NpPrNa+Bz8HzFusX9ojwAjuFv1Lhyxt4v6rFhund+w=; b=PboT0Ve94m1RHdy5/4MjRTnHBpwMkHtZpxrqlLroOy8fdI8lb8NFIeJTSWqLq48DM7 /3zqSI3FBFp/UpFhWda6CQn5w4HruXdIlOrYxk99oPG+mPoMENytAcfvIIL1cBbBzH3+ 3AnXH6dnPwmr5riSqepmlAed+dn15Smf5wQKaQbM62cJg50CYmE3HkWCk1bDIQWvN51C 0ELfHZZTLrrCKSxt/8c3WN95Ffp8s1YwO1ErBnvjS+MeaCRhrUavMurv144zINPnuic9 PzJOyV6oX2sMXtGmh/rTEyU5/1CkytozzoMPnHolbH1RX48VU0sDvAvJoFAdlW7ToYPs XhYg== X-Gm-Message-State: AOAM5323vLkvHsVW4kr17Y2JWyCRp1GCPhk7o2/D6OrSERqr1ihW6SAA 0gA7JGsiVbhoMRRdEWkFNm65VIYqNL31bYyV X-Google-Smtp-Source: ABdhPJwTCUHAIhmzAsWG6Hx/j6j1+ePR0qgOdomgLGI+Fid8PxjmP1rcK6BkhG60NGCyNuGxBHACGvhVDkyiO+aQ X-Received: from yosry.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:2327]) (user=yosryahmed job=sendgmr) by 2002:a65:554a:0:b0:3f6:885:b291 with SMTP id t10-20020a65554a000000b003f60885b291mr6191939pgr.608.1653009704939; Thu, 19 May 2022 18:21:44 -0700 (PDT) Date: Fri, 20 May 2022 01:21:32 +0000 In-Reply-To: <20220520012133.1217211-1-yosryahmed@google.com> Message-Id: <20220520012133.1217211-5-yosryahmed@google.com> Mime-Version: 1.0 References: <20220520012133.1217211-1-yosryahmed@google.com> X-Mailer: git-send-email 2.36.1.124.g0e6072fb45-goog Subject: [PATCH bpf-next v1 4/5] selftests/bpf: extend cgroup helpers From: Yosry Ahmed To: Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko , Martin KaFai Lau , Song Liu , Yonghong Song , John Fastabend , KP Singh , Hao Luo , Tejun Heo , Zefan Li , Johannes Weiner , Shuah Khan , Roman Gushchin , Michal Hocko Cc: Stanislav Fomichev , David Rientjes , Greg Thelen , Shakeel Butt , linux-kernel@vger.kernel.org, netdev@vger.kernel.org, bpf@vger.kernel.org, cgroups@vger.kernel.org, Yosry Ahmed Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: bpf@iogearbox.net This patch extends bpf selftests cgroup helpers in various ways: - Expose enable_controllers() that allows tests to enable all or a subset of controllers for a specific cgroup. - Add write_cgroup_file(). - 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. - 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 --- tools/testing/selftests/bpf/cgroup_helpers.c | 159 ++++++++++++++----- tools/testing/selftests/bpf/cgroup_helpers.h | 14 +- 2 files changed, 127 insertions(+), 46 deletions(-) diff --git a/tools/testing/selftests/bpf/cgroup_helpers.c b/tools/testing/selftests/bpf/cgroup_helpers.c index 9d59c3990ca8..48c8f794a347 100644 --- a/tools/testing/selftests/bpf/cgroup_helpers.c +++ b/tools/testing/selftests/bpf/cgroup_helpers.c @@ -33,49 +33,51 @@ #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; - } + /* 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, buf, sizeof(buf) - 1); - if (len < 0) { + 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 */ + return 0; + enable[len] = 0; close(fd); - log_err("Reading cgroup.controllers: %s", path); - return 1; - } - buf[len] = 0; - close(fd); - - /* No controllers available? We're probably on cgroup v1. */ - if (len == 0) - return 0; + } else + strncpy(enable, controllers, sizeof(enable)); snprintf(path, sizeof(path), "%s/cgroup.subtree_control", cgroup_path); cfd = open(path, O_RDWR); @@ -84,7 +86,7 @@ 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 +97,63 @@ 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); +} + + + +/** + * write_cgroup_file() - Write to a cgroup file + * @relative_path: The cgroup path, relative to the workdir + * @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]; + char file_path[PATH_MAX + 1]; + int fd; + + format_cgroup_path(cgroup_path, relative_path); + + snprintf(file_path, sizeof(file_path), "%s/%s", cgroup_path, file); + fd = open(file_path, O_RDWR); + if (fd < 0) { + log_err("Opening cgroup.subtree_control: %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; +} + + + /** * setup_cgroup_environment() - Setup the cgroup environment * @@ -133,7 +192,9 @@ 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 +234,7 @@ 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 +243,27 @@ 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); } @@ -214,7 +291,7 @@ void cleanup_cgroup_environment(void) /** * 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 +299,14 @@ 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 +321,13 @@ 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 +338,7 @@ 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..6b1d905557c7 100644 --- a/tools/testing/selftests/bpf/cgroup_helpers.h +++ b/tools/testing/selftests/bpf/cgroup_helpers.h @@ -10,11 +10,15 @@ __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 enable_controllers(const char *relative_path, const char *controllers); +int write_cgroup_file(const char *relative_path, const char *file, + const char *buf); +int cgroup_setup_and_join(const char *relative_path); +int create_and_get_cgroup(const char *relative_path); +unsigned long long get_cgroup_id(const char *relative_path); -int join_cgroup(const char *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 +30,4 @@ 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 */