diff options
Diffstat (limited to 'tools/testing/selftests/cgroup/test_core.c')
| -rw-r--r-- | tools/testing/selftests/cgroup/test_core.c | 888 |
1 files changed, 888 insertions, 0 deletions
diff --git a/tools/testing/selftests/cgroup/test_core.c b/tools/testing/selftests/cgroup/test_core.c new file mode 100644 index 000000000..600123503 --- /dev/null +++ b/tools/testing/selftests/cgroup/test_core.c @@ -0,0 +1,888 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + +#define _GNU_SOURCE +#include <linux/limits.h> +#include <linux/sched.h> +#include <sys/types.h> +#include <sys/mman.h> +#include <sys/wait.h> +#include <unistd.h> +#include <fcntl.h> +#include <sched.h> +#include <stdio.h> +#include <errno.h> +#include <signal.h> +#include <string.h> +#include <pthread.h> + +#include "../kselftest.h" +#include "cgroup_util.h" + +static int touch_anon(char *buf, size_t size) +{ + int fd; + char *pos = buf; + + fd = open("/dev/urandom", O_RDONLY); + if (fd < 0) + return -1; + + while (size > 0) { + ssize_t ret = read(fd, pos, size); + + if (ret < 0) { + if (errno != EINTR) { + close(fd); + return -1; + } + } else { + pos += ret; + size -= ret; + } + } + close(fd); + + return 0; +} + +static int alloc_and_touch_anon_noexit(const char *cgroup, void *arg) +{ + int ppid = getppid(); + size_t size = (size_t)arg; + void *buf; + + buf = mmap(NULL, size, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANON, + 0, 0); + if (buf == MAP_FAILED) + return -1; + + if (touch_anon((char *)buf, size)) { + munmap(buf, size); + return -1; + } + + while (getppid() == ppid) + sleep(1); + + munmap(buf, size); + return 0; +} + +/* + * Create a child process that allocates and touches 100MB, then waits to be + * killed. Wait until the child is attached to the cgroup, kill all processes + * in that cgroup and wait until "cgroup.procs" is empty. At this point try to + * destroy the empty cgroup. The test helps detect race conditions between + * dying processes leaving the cgroup and cgroup destruction path. + */ +static int test_cgcore_destroy(const char *root) +{ + int ret = KSFT_FAIL; + char *cg_test = NULL; + int child_pid; + char buf[PAGE_SIZE]; + + cg_test = cg_name(root, "cg_test"); + + if (!cg_test) + goto cleanup; + + for (int i = 0; i < 10; i++) { + if (cg_create(cg_test)) + goto cleanup; + + child_pid = cg_run_nowait(cg_test, alloc_and_touch_anon_noexit, + (void *) MB(100)); + + if (child_pid < 0) + goto cleanup; + + /* wait for the child to enter cgroup */ + if (cg_wait_for_proc_count(cg_test, 1)) + goto cleanup; + + if (cg_killall(cg_test)) + goto cleanup; + + /* wait for cgroup to be empty */ + while (1) { + if (cg_read(cg_test, "cgroup.procs", buf, sizeof(buf))) + goto cleanup; + if (buf[0] == '\0') + break; + usleep(1000); + } + + if (rmdir(cg_test)) + goto cleanup; + + if (waitpid(child_pid, NULL, 0) < 0) + goto cleanup; + } + ret = KSFT_PASS; +cleanup: + if (cg_test) + cg_destroy(cg_test); + free(cg_test); + return ret; +} + +/* + * A(0) - B(0) - C(1) + * \ D(0) + * + * A, B and C's "populated" fields would be 1 while D's 0. + * test that after the one process in C is moved to root, + * A,B and C's "populated" fields would flip to "0" and file + * modified events will be generated on the + * "cgroup.events" files of both cgroups. + */ +static int test_cgcore_populated(const char *root) +{ + int ret = KSFT_FAIL; + int err; + char *cg_test_a = NULL, *cg_test_b = NULL; + char *cg_test_c = NULL, *cg_test_d = NULL; + int cgroup_fd = -EBADF; + pid_t pid; + + cg_test_a = cg_name(root, "cg_test_a"); + cg_test_b = cg_name(root, "cg_test_a/cg_test_b"); + cg_test_c = cg_name(root, "cg_test_a/cg_test_b/cg_test_c"); + cg_test_d = cg_name(root, "cg_test_a/cg_test_b/cg_test_d"); + + if (!cg_test_a || !cg_test_b || !cg_test_c || !cg_test_d) + goto cleanup; + + if (cg_create(cg_test_a)) + goto cleanup; + + if (cg_create(cg_test_b)) + goto cleanup; + + if (cg_create(cg_test_c)) + goto cleanup; + + if (cg_create(cg_test_d)) + goto cleanup; + + if (cg_enter_current(cg_test_c)) + goto cleanup; + + if (cg_read_strcmp(cg_test_a, "cgroup.events", "populated 1\n")) + goto cleanup; + + if (cg_read_strcmp(cg_test_b, "cgroup.events", "populated 1\n")) + goto cleanup; + + if (cg_read_strcmp(cg_test_c, "cgroup.events", "populated 1\n")) + goto cleanup; + + if (cg_read_strcmp(cg_test_d, "cgroup.events", "populated 0\n")) + goto cleanup; + + if (cg_enter_current(root)) + goto cleanup; + + if (cg_read_strcmp(cg_test_a, "cgroup.events", "populated 0\n")) + goto cleanup; + + if (cg_read_strcmp(cg_test_b, "cgroup.events", "populated 0\n")) + goto cleanup; + + if (cg_read_strcmp(cg_test_c, "cgroup.events", "populated 0\n")) + goto cleanup; + + if (cg_read_strcmp(cg_test_d, "cgroup.events", "populated 0\n")) + goto cleanup; + + /* Test that we can directly clone into a new cgroup. */ + cgroup_fd = dirfd_open_opath(cg_test_d); + if (cgroup_fd < 0) + goto cleanup; + + pid = clone_into_cgroup(cgroup_fd); + if (pid < 0) { + if (errno == ENOSYS) + goto cleanup_pass; + goto cleanup; + } + + if (pid == 0) { + if (raise(SIGSTOP)) + exit(EXIT_FAILURE); + exit(EXIT_SUCCESS); + } + + err = cg_read_strcmp(cg_test_d, "cgroup.events", "populated 1\n"); + + (void)clone_reap(pid, WSTOPPED); + (void)kill(pid, SIGCONT); + (void)clone_reap(pid, WEXITED); + + if (err) + goto cleanup; + + if (cg_read_strcmp(cg_test_d, "cgroup.events", "populated 0\n")) + goto cleanup; + + /* Remove cgroup. */ + if (cg_test_d) { + cg_destroy(cg_test_d); + free(cg_test_d); + cg_test_d = NULL; + } + + pid = clone_into_cgroup(cgroup_fd); + if (pid < 0) + goto cleanup_pass; + if (pid == 0) + exit(EXIT_SUCCESS); + (void)clone_reap(pid, WEXITED); + goto cleanup; + +cleanup_pass: + ret = KSFT_PASS; + +cleanup: + if (cg_test_d) + cg_destroy(cg_test_d); + if (cg_test_c) + cg_destroy(cg_test_c); + if (cg_test_b) + cg_destroy(cg_test_b); + if (cg_test_a) + cg_destroy(cg_test_a); + free(cg_test_d); + free(cg_test_c); + free(cg_test_b); + free(cg_test_a); + if (cgroup_fd >= 0) + close(cgroup_fd); + return ret; +} + +/* + * A (domain threaded) - B (threaded) - C (domain) + * + * test that C can't be used until it is turned into a + * threaded cgroup. "cgroup.type" file will report "domain (invalid)" in + * these cases. Operations which fail due to invalid topology use + * EOPNOTSUPP as the errno. + */ +static int test_cgcore_invalid_domain(const char *root) +{ + int ret = KSFT_FAIL; + char *grandparent = NULL, *parent = NULL, *child = NULL; + + grandparent = cg_name(root, "cg_test_grandparent"); + parent = cg_name(root, "cg_test_grandparent/cg_test_parent"); + child = cg_name(root, "cg_test_grandparent/cg_test_parent/cg_test_child"); + if (!parent || !child || !grandparent) + goto cleanup; + + if (cg_create(grandparent)) + goto cleanup; + + if (cg_create(parent)) + goto cleanup; + + if (cg_create(child)) + goto cleanup; + + if (cg_write(parent, "cgroup.type", "threaded")) + goto cleanup; + + if (cg_read_strcmp(child, "cgroup.type", "domain invalid\n")) + goto cleanup; + + if (!cg_enter_current(child)) + goto cleanup; + + if (errno != EOPNOTSUPP) + goto cleanup; + + if (!clone_into_cgroup_run_wait(child)) + goto cleanup; + + if (errno == ENOSYS) + goto cleanup_pass; + + if (errno != EOPNOTSUPP) + goto cleanup; + +cleanup_pass: + ret = KSFT_PASS; + +cleanup: + cg_enter_current(root); + if (child) + cg_destroy(child); + if (parent) + cg_destroy(parent); + if (grandparent) + cg_destroy(grandparent); + free(child); + free(parent); + free(grandparent); + return ret; +} + +/* + * Test that when a child becomes threaded + * the parent type becomes domain threaded. + */ +static int test_cgcore_parent_becomes_threaded(const char *root) +{ + int ret = KSFT_FAIL; + char *parent = NULL, *child = NULL; + + parent = cg_name(root, "cg_test_parent"); + child = cg_name(root, "cg_test_parent/cg_test_child"); + if (!parent || !child) + goto cleanup; + + if (cg_create(parent)) + goto cleanup; + + if (cg_create(child)) + goto cleanup; + + if (cg_write(child, "cgroup.type", "threaded")) + goto cleanup; + + if (cg_read_strcmp(parent, "cgroup.type", "domain threaded\n")) + goto cleanup; + + ret = KSFT_PASS; + +cleanup: + if (child) + cg_destroy(child); + if (parent) + cg_destroy(parent); + free(child); + free(parent); + return ret; + +} + +/* + * Test that there's no internal process constrain on threaded cgroups. + * You can add threads/processes on a parent with a controller enabled. + */ +static int test_cgcore_no_internal_process_constraint_on_threads(const char *root) +{ + int ret = KSFT_FAIL; + char *parent = NULL, *child = NULL; + + if (cg_read_strstr(root, "cgroup.controllers", "cpu") || + cg_write(root, "cgroup.subtree_control", "+cpu")) { + ret = KSFT_SKIP; + goto cleanup; + } + + parent = cg_name(root, "cg_test_parent"); + child = cg_name(root, "cg_test_parent/cg_test_child"); + if (!parent || !child) + goto cleanup; + + if (cg_create(parent)) + goto cleanup; + + if (cg_create(child)) + goto cleanup; + + if (cg_write(parent, "cgroup.type", "threaded")) + goto cleanup; + + if (cg_write(child, "cgroup.type", "threaded")) + goto cleanup; + + if (cg_write(parent, "cgroup.subtree_control", "+cpu")) + goto cleanup; + + if (cg_enter_current(parent)) + goto cleanup; + + ret = KSFT_PASS; + +cleanup: + cg_enter_current(root); + cg_enter_current(root); + if (child) + cg_destroy(child); + if (parent) + cg_destroy(parent); + free(child); + free(parent); + return ret; +} + +/* + * Test that you can't enable a controller on a child if it's not enabled + * on the parent. + */ +static int test_cgcore_top_down_constraint_enable(const char *root) +{ + int ret = KSFT_FAIL; + char *parent = NULL, *child = NULL; + + parent = cg_name(root, "cg_test_parent"); + child = cg_name(root, "cg_test_parent/cg_test_child"); + if (!parent || !child) + goto cleanup; + + if (cg_create(parent)) + goto cleanup; + + if (cg_create(child)) + goto cleanup; + + if (!cg_write(child, "cgroup.subtree_control", "+memory")) + goto cleanup; + + ret = KSFT_PASS; + +cleanup: + if (child) + cg_destroy(child); + if (parent) + cg_destroy(parent); + free(child); + free(parent); + return ret; +} + +/* + * Test that you can't disable a controller on a parent + * if it's enabled in a child. + */ +static int test_cgcore_top_down_constraint_disable(const char *root) +{ + int ret = KSFT_FAIL; + char *parent = NULL, *child = NULL; + + parent = cg_name(root, "cg_test_parent"); + child = cg_name(root, "cg_test_parent/cg_test_child"); + if (!parent || !child) + goto cleanup; + + if (cg_create(parent)) + goto cleanup; + + if (cg_create(child)) + goto cleanup; + + if (cg_write(parent, "cgroup.subtree_control", "+memory")) + goto cleanup; + + if (cg_write(child, "cgroup.subtree_control", "+memory")) + goto cleanup; + + if (!cg_write(parent, "cgroup.subtree_control", "-memory")) + goto cleanup; + + ret = KSFT_PASS; + +cleanup: + if (child) + cg_destroy(child); + if (parent) + cg_destroy(parent); + free(child); + free(parent); + return ret; +} + +/* + * Test internal process constraint. + * You can't add a pid to a domain parent if a controller is enabled. + */ +static int test_cgcore_internal_process_constraint(const char *root) +{ + int ret = KSFT_FAIL; + char *parent = NULL, *child = NULL; + + parent = cg_name(root, "cg_test_parent"); + child = cg_name(root, "cg_test_parent/cg_test_child"); + if (!parent || !child) + goto cleanup; + + if (cg_create(parent)) + goto cleanup; + + if (cg_create(child)) + goto cleanup; + + if (cg_write(parent, "cgroup.subtree_control", "+memory")) + goto cleanup; + + if (!cg_enter_current(parent)) + goto cleanup; + + if (!clone_into_cgroup_run_wait(parent)) + goto cleanup; + + ret = KSFT_PASS; + +cleanup: + if (child) + cg_destroy(child); + if (parent) + cg_destroy(parent); + free(child); + free(parent); + return ret; +} + +static void *dummy_thread_fn(void *arg) +{ + return (void *)(size_t)pause(); +} + +/* + * Test threadgroup migration. + * All threads of a process are migrated together. + */ +static int test_cgcore_proc_migration(const char *root) +{ + int ret = KSFT_FAIL; + int t, c_threads = 0, n_threads = 13; + char *src = NULL, *dst = NULL; + pthread_t threads[n_threads]; + + src = cg_name(root, "cg_src"); + dst = cg_name(root, "cg_dst"); + if (!src || !dst) + goto cleanup; + + if (cg_create(src)) + goto cleanup; + if (cg_create(dst)) + goto cleanup; + + if (cg_enter_current(src)) + goto cleanup; + + for (c_threads = 0; c_threads < n_threads; ++c_threads) { + if (pthread_create(&threads[c_threads], NULL, dummy_thread_fn, NULL)) + goto cleanup; + } + + cg_enter_current(dst); + if (cg_read_lc(dst, "cgroup.threads") != n_threads + 1) + goto cleanup; + + ret = KSFT_PASS; + +cleanup: + for (t = 0; t < c_threads; ++t) { + pthread_cancel(threads[t]); + } + + for (t = 0; t < c_threads; ++t) { + pthread_join(threads[t], NULL); + } + + cg_enter_current(root); + + if (dst) + cg_destroy(dst); + if (src) + cg_destroy(src); + free(dst); + free(src); + return ret; +} + +static void *migrating_thread_fn(void *arg) +{ + int g, i, n_iterations = 1000; + char **grps = arg; + char lines[3][PATH_MAX]; + + for (g = 1; g < 3; ++g) + snprintf(lines[g], sizeof(lines[g]), "0::%s", grps[g] + strlen(grps[0])); + + for (i = 0; i < n_iterations; ++i) { + cg_enter_current_thread(grps[(i % 2) + 1]); + + if (proc_read_strstr(0, 1, "cgroup", lines[(i % 2) + 1])) + return (void *)-1; + } + return NULL; +} + +/* + * Test single thread migration. + * Threaded cgroups allow successful migration of a thread. + */ +static int test_cgcore_thread_migration(const char *root) +{ + int ret = KSFT_FAIL; + char *dom = NULL; + char line[PATH_MAX]; + char *grps[3] = { (char *)root, NULL, NULL }; + pthread_t thr; + void *retval; + + dom = cg_name(root, "cg_dom"); + grps[1] = cg_name(root, "cg_dom/cg_src"); + grps[2] = cg_name(root, "cg_dom/cg_dst"); + if (!grps[1] || !grps[2] || !dom) + goto cleanup; + + if (cg_create(dom)) + goto cleanup; + if (cg_create(grps[1])) + goto cleanup; + if (cg_create(grps[2])) + goto cleanup; + + if (cg_write(grps[1], "cgroup.type", "threaded")) + goto cleanup; + if (cg_write(grps[2], "cgroup.type", "threaded")) + goto cleanup; + + if (cg_enter_current(grps[1])) + goto cleanup; + + if (pthread_create(&thr, NULL, migrating_thread_fn, grps)) + goto cleanup; + + if (pthread_join(thr, &retval)) + goto cleanup; + + if (retval) + goto cleanup; + + snprintf(line, sizeof(line), "0::%s", grps[1] + strlen(grps[0])); + if (proc_read_strstr(0, 1, "cgroup", line)) + goto cleanup; + + ret = KSFT_PASS; + +cleanup: + cg_enter_current(root); + if (grps[2]) + cg_destroy(grps[2]); + if (grps[1]) + cg_destroy(grps[1]); + if (dom) + cg_destroy(dom); + free(grps[2]); + free(grps[1]); + free(dom); + return ret; +} + +/* + * cgroup migration permission check should be performed based on the + * credentials at the time of open instead of write. + */ +static int test_cgcore_lesser_euid_open(const char *root) +{ + const uid_t test_euid = 65534; /* usually nobody, any !root is fine */ + int ret = KSFT_FAIL; + char *cg_test_a = NULL, *cg_test_b = NULL; + char *cg_test_a_procs = NULL, *cg_test_b_procs = NULL; + int cg_test_b_procs_fd = -1; + uid_t saved_uid; + + cg_test_a = cg_name(root, "cg_test_a"); + cg_test_b = cg_name(root, "cg_test_b"); + + if (!cg_test_a || !cg_test_b) + goto cleanup; + + cg_test_a_procs = cg_name(cg_test_a, "cgroup.procs"); + cg_test_b_procs = cg_name(cg_test_b, "cgroup.procs"); + + if (!cg_test_a_procs || !cg_test_b_procs) + goto cleanup; + + if (cg_create(cg_test_a) || cg_create(cg_test_b)) + goto cleanup; + + if (cg_enter_current(cg_test_a)) + goto cleanup; + + if (chown(cg_test_a_procs, test_euid, -1) || + chown(cg_test_b_procs, test_euid, -1)) + goto cleanup; + + saved_uid = geteuid(); + if (seteuid(test_euid)) + goto cleanup; + + cg_test_b_procs_fd = open(cg_test_b_procs, O_RDWR); + + if (seteuid(saved_uid)) + goto cleanup; + + if (cg_test_b_procs_fd < 0) + goto cleanup; + + if (write(cg_test_b_procs_fd, "0", 1) >= 0 || errno != EACCES) + goto cleanup; + + ret = KSFT_PASS; + +cleanup: + cg_enter_current(root); + if (cg_test_b_procs_fd >= 0) + close(cg_test_b_procs_fd); + if (cg_test_b) + cg_destroy(cg_test_b); + if (cg_test_a) + cg_destroy(cg_test_a); + free(cg_test_b_procs); + free(cg_test_a_procs); + free(cg_test_b); + free(cg_test_a); + return ret; +} + +struct lesser_ns_open_thread_arg { + const char *path; + int fd; + int err; +}; + +static int lesser_ns_open_thread_fn(void *arg) +{ + struct lesser_ns_open_thread_arg *targ = arg; + + targ->fd = open(targ->path, O_RDWR); + targ->err = errno; + return 0; +} + +/* + * cgroup migration permission check should be performed based on the cgroup + * namespace at the time of open instead of write. + */ +static int test_cgcore_lesser_ns_open(const char *root) +{ + static char stack[65536]; + const uid_t test_euid = 65534; /* usually nobody, any !root is fine */ + int ret = KSFT_FAIL; + char *cg_test_a = NULL, *cg_test_b = NULL; + char *cg_test_a_procs = NULL, *cg_test_b_procs = NULL; + int cg_test_b_procs_fd = -1; + struct lesser_ns_open_thread_arg targ = { .fd = -1 }; + pid_t pid; + int status; + + cg_test_a = cg_name(root, "cg_test_a"); + cg_test_b = cg_name(root, "cg_test_b"); + + if (!cg_test_a || !cg_test_b) + goto cleanup; + + cg_test_a_procs = cg_name(cg_test_a, "cgroup.procs"); + cg_test_b_procs = cg_name(cg_test_b, "cgroup.procs"); + + if (!cg_test_a_procs || !cg_test_b_procs) + goto cleanup; + + if (cg_create(cg_test_a) || cg_create(cg_test_b)) + goto cleanup; + + if (cg_enter_current(cg_test_b)) + goto cleanup; + + if (chown(cg_test_a_procs, test_euid, -1) || + chown(cg_test_b_procs, test_euid, -1)) + goto cleanup; + + targ.path = cg_test_b_procs; + pid = clone(lesser_ns_open_thread_fn, stack + sizeof(stack), + CLONE_NEWCGROUP | CLONE_FILES | CLONE_VM | SIGCHLD, + &targ); + if (pid < 0) + goto cleanup; + + if (waitpid(pid, &status, 0) < 0) + goto cleanup; + + if (!WIFEXITED(status)) + goto cleanup; + + cg_test_b_procs_fd = targ.fd; + if (cg_test_b_procs_fd < 0) + goto cleanup; + + if (cg_enter_current(cg_test_a)) + goto cleanup; + + if ((status = write(cg_test_b_procs_fd, "0", 1)) >= 0 || errno != ENOENT) + goto cleanup; + + ret = KSFT_PASS; + +cleanup: + cg_enter_current(root); + if (cg_test_b_procs_fd >= 0) + close(cg_test_b_procs_fd); + if (cg_test_b) + cg_destroy(cg_test_b); + if (cg_test_a) + cg_destroy(cg_test_a); + free(cg_test_b_procs); + free(cg_test_a_procs); + free(cg_test_b); + free(cg_test_a); + return ret; +} + +#define T(x) { x, #x } +struct corecg_test { + int (*fn)(const char *root); + const char *name; +} tests[] = { + T(test_cgcore_internal_process_constraint), + T(test_cgcore_top_down_constraint_enable), + T(test_cgcore_top_down_constraint_disable), + T(test_cgcore_no_internal_process_constraint_on_threads), + T(test_cgcore_parent_becomes_threaded), + T(test_cgcore_invalid_domain), + T(test_cgcore_populated), + T(test_cgcore_proc_migration), + T(test_cgcore_thread_migration), + T(test_cgcore_destroy), + T(test_cgcore_lesser_euid_open), + T(test_cgcore_lesser_ns_open), +}; +#undef T + +int main(int argc, char *argv[]) +{ + char root[PATH_MAX]; + int i, ret = EXIT_SUCCESS; + + if (cg_find_unified_root(root, sizeof(root))) + ksft_exit_skip("cgroup v2 isn't mounted\n"); + + if (cg_read_strstr(root, "cgroup.subtree_control", "memory")) + if (cg_write(root, "cgroup.subtree_control", "+memory")) + ksft_exit_skip("Failed to set memory controller\n"); + + for (i = 0; i < ARRAY_SIZE(tests); i++) { + switch (tests[i].fn(root)) { + case KSFT_PASS: + ksft_test_result_pass("%s\n", tests[i].name); + break; + case KSFT_SKIP: + ksft_test_result_skip("%s\n", tests[i].name); + break; + default: + ret = EXIT_FAILURE; + ksft_test_result_fail("%s\n", tests[i].name); + break; + } + } + + return ret; +} |