diff options
Diffstat (limited to 'tools/testing/selftests/cgroup')
| -rw-r--r-- | tools/testing/selftests/cgroup/Makefile | 6 | ||||
| -rw-r--r-- | tools/testing/selftests/cgroup/cgroup_util.c | 126 | ||||
| -rw-r--r-- | tools/testing/selftests/cgroup/cgroup_util.h | 4 | ||||
| -rw-r--r-- | tools/testing/selftests/cgroup/test_core.c | 177 |
4 files changed, 310 insertions, 3 deletions
diff --git a/tools/testing/selftests/cgroup/Makefile b/tools/testing/selftests/cgroup/Makefile index 66aafe1f5746..967f268fde74 100644 --- a/tools/testing/selftests/cgroup/Makefile +++ b/tools/testing/selftests/cgroup/Makefile @@ -11,6 +11,6 @@ TEST_GEN_PROGS += test_freezer include ../lib.mk -$(OUTPUT)/test_memcontrol: cgroup_util.c -$(OUTPUT)/test_core: cgroup_util.c -$(OUTPUT)/test_freezer: cgroup_util.c +$(OUTPUT)/test_memcontrol: cgroup_util.c ../clone3/clone3_selftests.h +$(OUTPUT)/test_core: cgroup_util.c ../clone3/clone3_selftests.h +$(OUTPUT)/test_freezer: cgroup_util.c ../clone3/clone3_selftests.h diff --git a/tools/testing/selftests/cgroup/cgroup_util.c b/tools/testing/selftests/cgroup/cgroup_util.c index 8f7131dcf1ff..8a637ca7d73a 100644 --- a/tools/testing/selftests/cgroup/cgroup_util.c +++ b/tools/testing/selftests/cgroup/cgroup_util.c @@ -15,6 +15,7 @@ #include <unistd.h> #include "cgroup_util.h" +#include "../clone3/clone3_selftests.h" static ssize_t read_text(const char *path, char *buf, size_t max_len) { @@ -331,12 +332,112 @@ int cg_run(const char *cgroup, } } +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]; @@ -450,3 +551,28 @@ int proc_read_strstr(int pid, bool thread, const char *item, const char *needle) 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; +} diff --git a/tools/testing/selftests/cgroup/cgroup_util.h b/tools/testing/selftests/cgroup/cgroup_util.h index 49c54fbdb229..5a1305dd1f0b 100644 --- a/tools/testing/selftests/cgroup/cgroup_util.h +++ b/tools/testing/selftests/cgroup/cgroup_util.h @@ -50,3 +50,7 @@ extern int cg_wait_for_proc_count(const char *cgroup, int count); extern int cg_killall(const char *cgroup); extern ssize_t proc_read_text(int pid, bool thread, const char *item, char *buf, size_t size); extern int proc_read_strstr(int pid, bool thread, const char *item, const char *needle); +extern pid_t clone_into_cgroup(int cgroup_fd); +extern int clone_reap(pid_t pid, int options); +extern int clone_into_cgroup_run_wait(const char *cgroup); +extern int dirfd_open_opath(const char *dir); diff --git a/tools/testing/selftests/cgroup/test_core.c b/tools/testing/selftests/cgroup/test_core.c index e19ce940cd6a..3df648c37876 100644 --- a/tools/testing/selftests/cgroup/test_core.c +++ b/tools/testing/selftests/cgroup/test_core.c @@ -2,7 +2,10 @@ #include <linux/limits.h> #include <sys/types.h> +#include <sys/mman.h> +#include <sys/wait.h> #include <unistd.h> +#include <fcntl.h> #include <stdio.h> #include <errno.h> #include <signal.h> @@ -12,6 +15,115 @@ #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) @@ -25,8 +137,11 @@ 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"); @@ -78,6 +193,52 @@ static int test_cgcore_populated(const char *root) 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: @@ -93,6 +254,8 @@ cleanup: free(cg_test_c); free(cg_test_b); free(cg_test_a); + if (cgroup_fd >= 0) + close(cgroup_fd); return ret; } @@ -136,6 +299,16 @@ static int test_cgcore_invalid_domain(const char *root) 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: @@ -345,6 +518,9 @@ static int test_cgcore_internal_process_constraint(const char *root) if (!cg_enter_current(parent)) goto cleanup; + if (!clone_into_cgroup_run_wait(parent)) + goto cleanup; + ret = KSFT_PASS; cleanup: @@ -512,6 +688,7 @@ struct corecg_test { T(test_cgcore_populated), T(test_cgcore_proc_migration), T(test_cgcore_thread_migration), + T(test_cgcore_destroy), }; #undef T |