From 5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sat, 27 Apr 2024 12:05:51 +0200 Subject: Adding upstream version 5.10.209. Signed-off-by: Daniel Baumann --- tools/testing/selftests/cgroup/cgroup_util.c | 578 +++++++++++++++++++++++++++ 1 file changed, 578 insertions(+) create mode 100644 tools/testing/selftests/cgroup/cgroup_util.c (limited to 'tools/testing/selftests/cgroup/cgroup_util.c') diff --git a/tools/testing/selftests/cgroup/cgroup_util.c b/tools/testing/selftests/cgroup/cgroup_util.c new file mode 100644 index 000000000..5b16c7b0a --- /dev/null +++ b/tools/testing/selftests/cgroup/cgroup_util.c @@ -0,0 +1,578 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + +#define _GNU_SOURCE + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "cgroup_util.h" +#include "../clone3/clone3_selftests.h" + +static ssize_t read_text(const char *path, char *buf, size_t max_len) +{ + ssize_t len; + int fd; + + fd = open(path, O_RDONLY); + if (fd < 0) + return fd; + + len = read(fd, buf, max_len - 1); + if (len < 0) + goto out; + + buf[len] = 0; +out: + close(fd); + return len; +} + +static ssize_t write_text(const char *path, char *buf, ssize_t len) +{ + int fd; + + fd = open(path, O_WRONLY | O_APPEND); + if (fd < 0) + return fd; + + len = write(fd, buf, len); + if (len < 0) { + close(fd); + return len; + } + + close(fd); + + return len; +} + +char *cg_name(const char *root, const char *name) +{ + size_t len = strlen(root) + strlen(name) + 2; + char *ret = malloc(len); + + snprintf(ret, len, "%s/%s", root, name); + + return ret; +} + +char *cg_name_indexed(const char *root, const char *name, int index) +{ + size_t len = strlen(root) + strlen(name) + 10; + char *ret = malloc(len); + + snprintf(ret, len, "%s/%s_%d", root, name, index); + + return ret; +} + +char *cg_control(const char *cgroup, const char *control) +{ + size_t len = strlen(cgroup) + strlen(control) + 2; + char *ret = malloc(len); + + snprintf(ret, len, "%s/%s", cgroup, control); + + return ret; +} + +int cg_read(const char *cgroup, const char *control, char *buf, size_t len) +{ + char path[PATH_MAX]; + + snprintf(path, sizeof(path), "%s/%s", cgroup, control); + + if (read_text(path, buf, len) >= 0) + return 0; + + return -1; +} + +int cg_read_strcmp(const char *cgroup, const char *control, + const char *expected) +{ + size_t size; + char *buf; + int ret; + + /* Handle the case of comparing against empty string */ + if (!expected) + return -1; + else + size = strlen(expected) + 1; + + buf = malloc(size); + if (!buf) + return -1; + + if (cg_read(cgroup, control, buf, size)) { + free(buf); + return -1; + } + + ret = strcmp(expected, buf); + free(buf); + return ret; +} + +int cg_read_strstr(const char *cgroup, const char *control, const char *needle) +{ + char buf[PAGE_SIZE]; + + if (cg_read(cgroup, control, buf, sizeof(buf))) + return -1; + + return strstr(buf, needle) ? 0 : -1; +} + +long cg_read_long(const char *cgroup, const char *control) +{ + char buf[128]; + + if (cg_read(cgroup, control, buf, sizeof(buf))) + return -1; + + return atol(buf); +} + +long cg_read_key_long(const char *cgroup, const char *control, const char *key) +{ + char buf[PAGE_SIZE]; + char *ptr; + + if (cg_read(cgroup, control, buf, sizeof(buf))) + return -1; + + ptr = strstr(buf, key); + if (!ptr) + return -1; + + return atol(ptr + strlen(key)); +} + +long cg_read_lc(const char *cgroup, const char *control) +{ + char buf[PAGE_SIZE]; + const char delim[] = "\n"; + char *line; + long cnt = 0; + + if (cg_read(cgroup, control, buf, sizeof(buf))) + return -1; + + for (line = strtok(buf, delim); line; line = strtok(NULL, delim)) + cnt++; + + return cnt; +} + +int cg_write(const char *cgroup, const char *control, char *buf) +{ + char path[PATH_MAX]; + ssize_t len = strlen(buf); + + snprintf(path, sizeof(path), "%s/%s", cgroup, control); + + if (write_text(path, buf, len) == len) + return 0; + + return -1; +} + +int cg_find_unified_root(char *root, size_t len) +{ + char buf[10 * PAGE_SIZE]; + char *fs, *mount, *type; + const char delim[] = "\n\t "; + + if (read_text("/proc/self/mounts", buf, sizeof(buf)) <= 0) + return -1; + + /* + * Example: + * cgroup /sys/fs/cgroup cgroup2 rw,seclabel,noexec,relatime 0 0 + */ + for (fs = strtok(buf, delim); fs; fs = strtok(NULL, delim)) { + mount = strtok(NULL, delim); + type = strtok(NULL, delim); + strtok(NULL, delim); + strtok(NULL, delim); + strtok(NULL, delim); + + if (strcmp(type, "cgroup2") == 0) { + strncpy(root, mount, len); + return 0; + } + } + + return -1; +} + +int cg_create(const char *cgroup) +{ + return mkdir(cgroup, 0755); +} + +int cg_wait_for_proc_count(const char *cgroup, int count) +{ + char buf[10 * PAGE_SIZE] = {0}; + int attempts; + char *ptr; + + for (attempts = 10; attempts >= 0; attempts--) { + int nr = 0; + + if (cg_read(cgroup, "cgroup.procs", buf, sizeof(buf))) + break; + + for (ptr = buf; *ptr; ptr++) + if (*ptr == '\n') + nr++; + + if (nr >= count) + return 0; + + usleep(100000); + } + + return -1; +} + +int cg_killall(const char *cgroup) +{ + char buf[PAGE_SIZE]; + char *ptr = buf; + + if (cg_read(cgroup, "cgroup.procs", buf, sizeof(buf))) + return -1; + + while (ptr < buf + sizeof(buf)) { + int pid = strtol(ptr, &ptr, 10); + + if (pid == 0) + break; + if (*ptr) + ptr++; + else + break; + if (kill(pid, SIGKILL)) + return -1; + } + + return 0; +} + +int cg_destroy(const char *cgroup) +{ + int ret; + +retry: + ret = rmdir(cgroup); + if (ret && errno == EBUSY) { + cg_killall(cgroup); + usleep(100); + goto retry; + } + + if (ret && errno == ENOENT) + ret = 0; + + return ret; +} + +int cg_enter(const char *cgroup, int pid) +{ + char pidbuf[64]; + + snprintf(pidbuf, sizeof(pidbuf), "%d", pid); + return cg_write(cgroup, "cgroup.procs", pidbuf); +} + +int cg_enter_current(const char *cgroup) +{ + return cg_write(cgroup, "cgroup.procs", "0"); +} + +int cg_enter_current_thread(const char *cgroup) +{ + return cg_write(cgroup, "cgroup.threads", "0"); +} + +int cg_run(const char *cgroup, + int (*fn)(const char *cgroup, void *arg), + void *arg) +{ + int pid, retcode; + + pid = fork(); + if (pid < 0) { + return pid; + } else if (pid == 0) { + char buf[64]; + + snprintf(buf, sizeof(buf), "%d", getpid()); + if (cg_write(cgroup, "cgroup.procs", buf)) + exit(EXIT_FAILURE); + exit(fn(cgroup, arg)); + } else { + waitpid(pid, &retcode, 0); + if (WIFEXITED(retcode)) + return WEXITSTATUS(retcode); + else + return -1; + } +} + +pid_t clone_into_cgroup(int cgroup_fd) +{ +#ifdef CLONE_ARGS_SIZE_VER2 + pid_t pid; + + struct __clone_args args = { + .flags = CLONE_INTO_CGROUP, + .exit_signal = SIGCHLD, + .cgroup = cgroup_fd, + }; + + pid = sys_clone3(&args, sizeof(struct __clone_args)); + /* + * Verify that this is a genuine test failure: + * ENOSYS -> clone3() not available + * E2BIG -> CLONE_INTO_CGROUP not available + */ + if (pid < 0 && (errno == ENOSYS || errno == E2BIG)) + goto pretend_enosys; + + return pid; + +pretend_enosys: +#endif + errno = ENOSYS; + return -ENOSYS; +} + +int clone_reap(pid_t pid, int options) +{ + int ret; + siginfo_t info = { + .si_signo = 0, + }; + +again: + ret = waitid(P_PID, pid, &info, options | __WALL | __WNOTHREAD); + if (ret < 0) { + if (errno == EINTR) + goto again; + return -1; + } + + if (options & WEXITED) { + if (WIFEXITED(info.si_status)) + return WEXITSTATUS(info.si_status); + } + + if (options & WSTOPPED) { + if (WIFSTOPPED(info.si_status)) + return WSTOPSIG(info.si_status); + } + + if (options & WCONTINUED) { + if (WIFCONTINUED(info.si_status)) + return 0; + } + + return -1; +} + +int dirfd_open_opath(const char *dir) +{ + return open(dir, O_DIRECTORY | O_CLOEXEC | O_NOFOLLOW | O_PATH); +} + +#define close_prot_errno(fd) \ + if (fd >= 0) { \ + int _e_ = errno; \ + close(fd); \ + errno = _e_; \ + } + +static int clone_into_cgroup_run_nowait(const char *cgroup, + int (*fn)(const char *cgroup, void *arg), + void *arg) +{ + int cgroup_fd; + pid_t pid; + + cgroup_fd = dirfd_open_opath(cgroup); + if (cgroup_fd < 0) + return -1; + + pid = clone_into_cgroup(cgroup_fd); + close_prot_errno(cgroup_fd); + if (pid == 0) + exit(fn(cgroup, arg)); + + return pid; +} + +int cg_run_nowait(const char *cgroup, + int (*fn)(const char *cgroup, void *arg), + void *arg) +{ + int pid; + + pid = clone_into_cgroup_run_nowait(cgroup, fn, arg); + if (pid > 0) + return pid; + + /* Genuine test failure. */ + if (pid < 0 && errno != ENOSYS) + return -1; + + pid = fork(); + if (pid == 0) { + char buf[64]; + + snprintf(buf, sizeof(buf), "%d", getpid()); + if (cg_write(cgroup, "cgroup.procs", buf)) + exit(EXIT_FAILURE); + exit(fn(cgroup, arg)); + } + + return pid; +} + +int get_temp_fd(void) +{ + return open(".", O_TMPFILE | O_RDWR | O_EXCL); +} + +int alloc_pagecache(int fd, size_t size) +{ + char buf[PAGE_SIZE]; + struct stat st; + int i; + + if (fstat(fd, &st)) + goto cleanup; + + size += st.st_size; + + if (ftruncate(fd, size)) + goto cleanup; + + for (i = 0; i < size; i += sizeof(buf)) + read(fd, buf, sizeof(buf)); + + return 0; + +cleanup: + return -1; +} + +int alloc_anon(const char *cgroup, void *arg) +{ + size_t size = (unsigned long)arg; + char *buf, *ptr; + + buf = malloc(size); + for (ptr = buf; ptr < buf + size; ptr += PAGE_SIZE) + *ptr = 0; + + free(buf); + return 0; +} + +int is_swap_enabled(void) +{ + char buf[PAGE_SIZE]; + const char delim[] = "\n"; + int cnt = 0; + char *line; + + if (read_text("/proc/swaps", buf, sizeof(buf)) <= 0) + return -1; + + for (line = strtok(buf, delim); line; line = strtok(NULL, delim)) + cnt++; + + return cnt > 1; +} + +int set_oom_adj_score(int pid, int score) +{ + char path[PATH_MAX]; + int fd, len; + + sprintf(path, "/proc/%d/oom_score_adj", pid); + + fd = open(path, O_WRONLY | O_APPEND); + if (fd < 0) + return fd; + + len = dprintf(fd, "%d", score); + if (len < 0) { + close(fd); + return len; + } + + close(fd); + return 0; +} + +ssize_t proc_read_text(int pid, bool thread, const char *item, char *buf, size_t size) +{ + char path[PATH_MAX]; + + if (!pid) + snprintf(path, sizeof(path), "/proc/%s/%s", + thread ? "thread-self" : "self", item); + else + snprintf(path, sizeof(path), "/proc/%d/%s", pid, item); + + return read_text(path, buf, size); +} + +int proc_read_strstr(int pid, bool thread, const char *item, const char *needle) +{ + char buf[PAGE_SIZE]; + + if (proc_read_text(pid, thread, item, buf, sizeof(buf)) < 0) + return -1; + + return strstr(buf, needle) ? 0 : -1; +} + +int clone_into_cgroup_run_wait(const char *cgroup) +{ + int cgroup_fd; + pid_t pid; + + cgroup_fd = dirfd_open_opath(cgroup); + if (cgroup_fd < 0) + return -1; + + pid = clone_into_cgroup(cgroup_fd); + close_prot_errno(cgroup_fd); + if (pid < 0) + return -1; + + if (pid == 0) + exit(EXIT_SUCCESS); + + /* + * We don't care whether this fails. We only care whether the initial + * clone succeeded. + */ + (void)clone_reap(pid, WEXITED); + return 0; +} -- cgit v1.2.3