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-rw-r--r--samples/bpf/cgroup_helpers.c178
1 files changed, 0 insertions, 178 deletions
diff --git a/samples/bpf/cgroup_helpers.c b/samples/bpf/cgroup_helpers.c
deleted file mode 100644
index 09afaddfc9ba..000000000000
--- a/samples/bpf/cgroup_helpers.c
+++ /dev/null
@@ -1,178 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-#define _GNU_SOURCE
-#include <sched.h>
-#include <sys/mount.h>
-#include <sys/stat.h>
-#include <sys/types.h>
-#include <linux/limits.h>
-#include <stdio.h>
-#include <linux/sched.h>
-#include <fcntl.h>
-#include <unistd.h>
-#include <ftw.h>
-
-
-#include "cgroup_helpers.h"
-
-/*
- * To avoid relying on the system setup, when setup_cgroup_env is called
- * we create a new mount namespace, and cgroup namespace. The cgroup2
- * root is mounted at CGROUP_MOUNT_PATH
- *
- * Unfortunately, most people don't have cgroupv2 enabled at this point in time.
- * It's easier to create our own mount namespace and manage it ourselves.
- *
- * We assume /mnt exists.
- */
-
-#define WALK_FD_LIMIT 16
-#define CGROUP_MOUNT_PATH "/mnt"
-#define CGROUP_WORK_DIR "/cgroup-test-work-dir"
-#define format_cgroup_path(buf, path) \
- snprintf(buf, sizeof(buf), "%s%s%s", CGROUP_MOUNT_PATH, \
- CGROUP_WORK_DIR, path)
-
-/**
- * setup_cgroup_environment() - Setup the cgroup environment
- *
- * After calling this function, cleanup_cgroup_environment should be called
- * once testing is complete.
- *
- * This function will print an error to stderr and return 1 if it is unable
- * to setup the cgroup environment. If setup is successful, 0 is returned.
- */
-int setup_cgroup_environment(void)
-{
- char cgroup_workdir[PATH_MAX + 1];
-
- format_cgroup_path(cgroup_workdir, "");
-
- if (unshare(CLONE_NEWNS)) {
- log_err("unshare");
- return 1;
- }
-
- if (mount("none", "/", NULL, MS_REC | MS_PRIVATE, NULL)) {
- log_err("mount fakeroot");
- return 1;
- }
-
- if (mount("none", CGROUP_MOUNT_PATH, "cgroup2", 0, NULL)) {
- log_err("mount cgroup2");
- return 1;
- }
-
- /* Cleanup existing failed runs, now that the environment is setup */
- cleanup_cgroup_environment();
-
- if (mkdir(cgroup_workdir, 0777) && errno != EEXIST) {
- log_err("mkdir cgroup work dir");
- return 1;
- }
-
- return 0;
-}
-
-static int nftwfunc(const char *filename, const struct stat *statptr,
- int fileflags, struct FTW *pfwt)
-{
- if ((fileflags & FTW_D) && rmdir(filename))
- log_err("Removing cgroup: %s", filename);
- return 0;
-}
-
-
-static int join_cgroup_from_top(char *cgroup_path)
-{
- char cgroup_procs_path[PATH_MAX + 1];
- pid_t pid = getpid();
- int fd, rc = 0;
-
- snprintf(cgroup_procs_path, sizeof(cgroup_procs_path),
- "%s/cgroup.procs", cgroup_path);
-
- fd = open(cgroup_procs_path, O_WRONLY);
- if (fd < 0) {
- log_err("Opening Cgroup Procs: %s", cgroup_procs_path);
- return 1;
- }
-
- if (dprintf(fd, "%d\n", pid) < 0) {
- log_err("Joining Cgroup");
- rc = 1;
- }
-
- close(fd);
- return rc;
-}
-
-/**
- * join_cgroup() - Join a cgroup
- * @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
- * would actually put the calling process into the cgroup
- * "/cgroup-test-work-dir/my-cgroup"
- *
- * On success, it returns 0, otherwise on failure it returns 1.
- */
-int join_cgroup(char *path)
-{
- char cgroup_path[PATH_MAX + 1];
-
- format_cgroup_path(cgroup_path, path);
- return join_cgroup_from_top(cgroup_path);
-}
-
-/**
- * cleanup_cgroup_environment() - Cleanup Cgroup Testing Environment
- *
- * This is an idempotent function to delete all temporary cgroups that
- * have been created during the test, including the cgroup testing work
- * directory.
- *
- * At call time, it moves the calling process to the root cgroup, and then
- * runs the deletion process. It is idempotent, and should not fail, unless
- * a process is lingering.
- *
- * On failure, it will print an error to stderr, and try to continue.
- */
-void cleanup_cgroup_environment(void)
-{
- char cgroup_workdir[PATH_MAX + 1];
-
- format_cgroup_path(cgroup_workdir, "");
- join_cgroup_from_top(CGROUP_MOUNT_PATH);
- nftw(cgroup_workdir, nftwfunc, WALK_FD_LIMIT, FTW_DEPTH | FTW_MOUNT);
-}
-
-/**
- * create_and_get_cgroup() - Create a cgroup, relative to workdir, and get the FD
- * @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.
- *
- * On success, it returns the file descriptor. On failure it returns 0.
- * If there is a failure, it prints the error to stderr.
- */
-int create_and_get_cgroup(char *path)
-{
- char cgroup_path[PATH_MAX + 1];
- int fd;
-
- format_cgroup_path(cgroup_path, path);
- if (mkdir(cgroup_path, 0777) && errno != EEXIST) {
- log_err("mkdiring cgroup");
- return 0;
- }
-
- fd = open(cgroup_path, O_RDONLY);
- if (fd < 0) {
- log_err("Opening Cgroup");
- return 0;
- }
-
- return fd;
-}