The following commit has been merged into the timers/core branch of tip: Commit-ID: 61c57676035df29a0a61991f4389e884ba0b68d7 Gitweb: https://git.kernel.org/tip/61c57676035df29a0a61991f4389e884ba0b68d7 Author: Dmitry Safonov <dima@xxxxxxxxxx> AuthorDate: Tue, 12 Nov 2019 01:27:17 Committer: Thomas Gleixner <tglx@xxxxxxxxxxxxx> CommitterDate: Tue, 14 Jan 2020 12:21:00 +01:00 selftests/timens: Add Time Namespace test for supported clocks A test to check that all supported clocks work on host and inside a new time namespace. Use both ways to get time: through VDSO and by entering the kernel with implicit syscall. Introduce a new timens directory in selftests framework for the next timens tests. Output on success: 1..10 ok 1 Passed for CLOCK_BOOTTIME (syscall) ok 2 Passed for CLOCK_BOOTTIME (vdso) ok 3 Passed for CLOCK_BOOTTIME_ALARM (syscall) ok 4 Passed for CLOCK_BOOTTIME_ALARM (vdso) ok 5 Passed for CLOCK_MONOTONIC (syscall) ok 6 Passed for CLOCK_MONOTONIC (vdso) ok 7 Passed for CLOCK_MONOTONIC_COARSE (syscall) ok 8 Passed for CLOCK_MONOTONIC_COARSE (vdso) ok 9 Passed for CLOCK_MONOTONIC_RAW (syscall) ok 10 Passed for CLOCK_MONOTONIC_RAW (vdso) # Pass 10 Fail 0 Xfail 0 Xpass 0 Skip 0 Error 0 Output with lack of permissions: 1..10 not ok 1 # SKIP need to run as root Output without support of time namespaces: 1..10 not ok 1 # SKIP Time namespaces are not supported Co-developed-by: Andrei Vagin <avagin@xxxxxxxxxx> Signed-off-by: Andrei Vagin <avagin@xxxxxxxxx> Signed-off-by: Dmitry Safonov <dima@xxxxxxxxxx> Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Link: https://lore.kernel.org/r/20191112012724.250792-29-dima@xxxxxxxxxx --- tools/testing/selftests/Makefile | 1 +- tools/testing/selftests/timens/.gitignore | 1 +- tools/testing/selftests/timens/Makefile | 6 +- tools/testing/selftests/timens/config | 1 +- tools/testing/selftests/timens/log.h | 26 +++- tools/testing/selftests/timens/timens.c | 190 +++++++++++++++++++++- tools/testing/selftests/timens/timens.h | 100 +++++++++++- 7 files changed, 325 insertions(+) create mode 100644 tools/testing/selftests/timens/.gitignore create mode 100644 tools/testing/selftests/timens/Makefile create mode 100644 tools/testing/selftests/timens/config create mode 100644 tools/testing/selftests/timens/log.h create mode 100644 tools/testing/selftests/timens/timens.c create mode 100644 tools/testing/selftests/timens/timens.h diff --git a/tools/testing/selftests/Makefile b/tools/testing/selftests/Makefile index b001c60..c4939a2 100644 --- a/tools/testing/selftests/Makefile +++ b/tools/testing/selftests/Makefile @@ -50,6 +50,7 @@ TARGETS += splice TARGETS += static_keys TARGETS += sync TARGETS += sysctl +TARGETS += timens ifneq (1, $(quicktest)) TARGETS += timers endif diff --git a/tools/testing/selftests/timens/.gitignore b/tools/testing/selftests/timens/.gitignore new file mode 100644 index 0000000..27a6932 --- /dev/null +++ b/tools/testing/selftests/timens/.gitignore @@ -0,0 +1 @@ +timens diff --git a/tools/testing/selftests/timens/Makefile b/tools/testing/selftests/timens/Makefile new file mode 100644 index 0000000..49a9dcc --- /dev/null +++ b/tools/testing/selftests/timens/Makefile @@ -0,0 +1,6 @@ +TEST_GEN_PROGS := timens + +CFLAGS := -Wall -Werror +LDFLAGS := -lrt + +include ../lib.mk diff --git a/tools/testing/selftests/timens/config b/tools/testing/selftests/timens/config new file mode 100644 index 0000000..4480620 --- /dev/null +++ b/tools/testing/selftests/timens/config @@ -0,0 +1 @@ +CONFIG_TIME_NS=y diff --git a/tools/testing/selftests/timens/log.h b/tools/testing/selftests/timens/log.h new file mode 100644 index 0000000..db64df2 --- /dev/null +++ b/tools/testing/selftests/timens/log.h @@ -0,0 +1,26 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + +#ifndef __SELFTEST_TIMENS_LOG_H__ +#define __SELFTEST_TIMENS_LOG_H__ + +#define pr_msg(fmt, lvl, ...) \ + ksft_print_msg("[%s] (%s:%d)\t" fmt "\n", \ + lvl, __FILE__, __LINE__, ##__VA_ARGS__) + +#define pr_p(func, fmt, ...) func(fmt ": %m", ##__VA_ARGS__) + +#define pr_err(fmt, ...) \ + ({ \ + ksft_test_result_error(fmt "\n", ##__VA_ARGS__); \ + -1; \ + }) + +#define pr_fail(fmt, ...) \ + ({ \ + ksft_test_result_fail(fmt, ##__VA_ARGS__); \ + -1; \ + }) + +#define pr_perror(fmt, ...) pr_p(pr_err, fmt, ##__VA_ARGS__) + +#endif diff --git a/tools/testing/selftests/timens/timens.c b/tools/testing/selftests/timens/timens.c new file mode 100644 index 0000000..559d26e --- /dev/null +++ b/tools/testing/selftests/timens/timens.c @@ -0,0 +1,190 @@ +// SPDX-License-Identifier: GPL-2.0 +#define _GNU_SOURCE +#include <errno.h> +#include <fcntl.h> +#include <sched.h> +#include <stdio.h> +#include <stdbool.h> +#include <sys/stat.h> +#include <sys/syscall.h> +#include <sys/types.h> +#include <time.h> +#include <unistd.h> +#include <time.h> +#include <string.h> + +#include "log.h" +#include "timens.h" + +/* + * Test shouldn't be run for a day, so add 10 days to child + * time and check parent's time to be in the same day. + */ +#define DAY_IN_SEC (60*60*24) +#define TEN_DAYS_IN_SEC (10*DAY_IN_SEC) + +#define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0])) + +struct test_clock { + clockid_t id; + char *name; + /* + * off_id is -1 if a clock has own offset, or it contains an index + * which contains a right offset of this clock. + */ + int off_id; + time_t offset; +}; + +#define ct(clock, off_id) { clock, #clock, off_id } +static struct test_clock clocks[] = { + ct(CLOCK_BOOTTIME, -1), + ct(CLOCK_BOOTTIME_ALARM, 1), + ct(CLOCK_MONOTONIC, -1), + ct(CLOCK_MONOTONIC_COARSE, 1), + ct(CLOCK_MONOTONIC_RAW, 1), +}; +#undef ct + +static int child_ns, parent_ns = -1; + +static int switch_ns(int fd) +{ + if (setns(fd, CLONE_NEWTIME)) { + pr_perror("setns()"); + return -1; + } + + return 0; +} + +static int init_namespaces(void) +{ + char path[] = "/proc/self/ns/time_for_children"; + struct stat st1, st2; + + if (parent_ns == -1) { + parent_ns = open(path, O_RDONLY); + if (parent_ns <= 0) + return pr_perror("Unable to open %s", path); + } + + if (fstat(parent_ns, &st1)) + return pr_perror("Unable to stat the parent timens"); + + if (unshare_timens()) + return -1; + + child_ns = open(path, O_RDONLY); + if (child_ns <= 0) + return pr_perror("Unable to open %s", path); + + if (fstat(child_ns, &st2)) + return pr_perror("Unable to stat the timens"); + + if (st1.st_ino == st2.st_ino) + return pr_perror("The same child_ns after CLONE_NEWTIME"); + + return 0; +} + +static int test_gettime(clockid_t clock_index, bool raw_syscall, time_t offset) +{ + struct timespec child_ts_new, parent_ts_old, cur_ts; + char *entry = raw_syscall ? "syscall" : "vdso"; + double precision = 0.0; + + if (check_skip(clocks[clock_index].id)) + return 0; + + switch (clocks[clock_index].id) { + case CLOCK_MONOTONIC_COARSE: + case CLOCK_MONOTONIC_RAW: + precision = -2.0; + break; + } + + if (switch_ns(parent_ns)) + return pr_err("switch_ns(%d)", child_ns); + + if (_gettime(clocks[clock_index].id, &parent_ts_old, raw_syscall)) + return -1; + + child_ts_new.tv_nsec = parent_ts_old.tv_nsec; + child_ts_new.tv_sec = parent_ts_old.tv_sec + offset; + + if (switch_ns(child_ns)) + return pr_err("switch_ns(%d)", child_ns); + + if (_gettime(clocks[clock_index].id, &cur_ts, raw_syscall)) + return -1; + + if (difftime(cur_ts.tv_sec, child_ts_new.tv_sec) < precision) { + ksft_test_result_fail( + "Child's %s (%s) time has not changed: %lu -> %lu [%lu]\n", + clocks[clock_index].name, entry, parent_ts_old.tv_sec, + child_ts_new.tv_sec, cur_ts.tv_sec); + return -1; + } + + if (switch_ns(parent_ns)) + return pr_err("switch_ns(%d)", parent_ns); + + if (_gettime(clocks[clock_index].id, &cur_ts, raw_syscall)) + return -1; + + if (difftime(cur_ts.tv_sec, parent_ts_old.tv_sec) > DAY_IN_SEC) { + ksft_test_result_fail( + "Parent's %s (%s) time has changed: %lu -> %lu [%lu]\n", + clocks[clock_index].name, entry, parent_ts_old.tv_sec, + child_ts_new.tv_sec, cur_ts.tv_sec); + /* Let's play nice and put it closer to original */ + clock_settime(clocks[clock_index].id, &cur_ts); + return -1; + } + + ksft_test_result_pass("Passed for %s (%s)\n", + clocks[clock_index].name, entry); + return 0; +} + +int main(int argc, char *argv[]) +{ + unsigned int i; + time_t offset; + int ret = 0; + + nscheck(); + + check_config_posix_timers(); + + ksft_set_plan(ARRAY_SIZE(clocks) * 2); + + if (init_namespaces()) + return 1; + + /* Offsets have to be set before tasks enter the namespace. */ + for (i = 0; i < ARRAY_SIZE(clocks); i++) { + if (clocks[i].off_id != -1) + continue; + offset = TEN_DAYS_IN_SEC + i * 1000; + clocks[i].offset = offset; + if (_settime(clocks[i].id, offset)) + return 1; + } + + for (i = 0; i < ARRAY_SIZE(clocks); i++) { + if (clocks[i].off_id != -1) + offset = clocks[clocks[i].off_id].offset; + else + offset = clocks[i].offset; + ret |= test_gettime(i, true, offset); + ret |= test_gettime(i, false, offset); + } + + if (ret) + ksft_exit_fail(); + + ksft_exit_pass(); + return !!ret; +} diff --git a/tools/testing/selftests/timens/timens.h b/tools/testing/selftests/timens/timens.h new file mode 100644 index 0000000..e09e7e3 --- /dev/null +++ b/tools/testing/selftests/timens/timens.h @@ -0,0 +1,100 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef __TIMENS_H__ +#define __TIMENS_H__ + +#include <fcntl.h> +#include <unistd.h> +#include <stdlib.h> +#include <stdbool.h> + +#include "../kselftest.h" + +#ifndef CLONE_NEWTIME +# define CLONE_NEWTIME 0x00000080 +#endif + +static int config_posix_timers = true; + +static inline void check_config_posix_timers(void) +{ + if (timer_create(-1, 0, 0) == -1 && errno == ENOSYS) + config_posix_timers = false; +} + +static inline bool check_skip(int clockid) +{ + if (config_posix_timers) + return false; + + switch (clockid) { + /* Only these clocks are supported without CONFIG_POSIX_TIMERS. */ + case CLOCK_BOOTTIME: + case CLOCK_MONOTONIC: + case CLOCK_REALTIME: + return false; + default: + ksft_test_result_skip("Posix Clocks & timers are not supported\n"); + return true; + } + + return false; +} + +static inline int unshare_timens(void) +{ + if (unshare(CLONE_NEWTIME)) { + if (errno == EPERM) + ksft_exit_skip("need to run as root\n"); + return pr_perror("Can't unshare() timens"); + } + return 0; +} + +static inline int _settime(clockid_t clk_id, time_t offset) +{ + int fd, len; + char buf[4096]; + + if (clk_id == CLOCK_MONOTONIC_COARSE || clk_id == CLOCK_MONOTONIC_RAW) + clk_id = CLOCK_MONOTONIC; + + len = snprintf(buf, sizeof(buf), "%d %ld 0", clk_id, offset); + + fd = open("/proc/self/timens_offsets", O_WRONLY); + if (fd < 0) + return pr_perror("/proc/self/timens_offsets"); + + if (write(fd, buf, len) != len) + return pr_perror("/proc/self/timens_offsets"); + + close(fd); + + return 0; +} + +static inline int _gettime(clockid_t clk_id, struct timespec *res, bool raw_syscall) +{ + int err; + + if (!raw_syscall) { + if (clock_gettime(clk_id, res)) { + pr_perror("clock_gettime(%d)", (int)clk_id); + return -1; + } + return 0; + } + + err = syscall(SYS_clock_gettime, clk_id, res); + if (err) + pr_perror("syscall(SYS_clock_gettime(%d))", (int)clk_id); + + return err; +} + +static inline void nscheck(void) +{ + if (access("/proc/self/ns/time", F_OK) < 0) + ksft_exit_skip("Time namespaces are not supported\n"); +} + +#endif