[RFC,16/20] selftest: Add Time Namespace test for supported clocks
diff mbox series

Message ID 20180919205037.9574-17-dima@arista.com
State New
Headers show
Series
  • ns: Introduce Time Namespace
Related show

Commit Message

Dmitry Safonov Sept. 19, 2018, 8:50 p.m. UTC
This test checks that all supported clocks can be changed by
clock_settime.

Cc: linux-kselftest@vger.kernel.org
Signed-off-by: Andrei Vagin <avagin@openvz.org>
Co-developed-by: Andrei Vagin <avagin@openvz.org>
Signed-off-by: Dmitry Safonov <dima@arista.com>
---
 tools/testing/selftests/timens/.gitignore |   1 +
 tools/testing/selftests/timens/Makefile   |   5 +
 tools/testing/selftests/timens/config     |   1 +
 tools/testing/selftests/timens/log.h      |  21 ++++
 tools/testing/selftests/timens/timens.c   | 196 ++++++++++++++++++++++++++++++
 5 files changed, 224 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

Comments

shuah Sept. 24, 2018, 9:36 p.m. UTC | #1
Hi Dmitry,

Thanks for adding tests with the kernel changes.

On 09/19/2018 02:50 PM, Dmitry Safonov wrote:
> This test checks that all supported clocks can be changed by
> clock_settime.

It would good to elaborate a bit more on the nature of the tests in the
here. Also a few things to consider.

I noticed that this test isn't added to selftests/Makefile as TARGET. If it is
an oversight, please make that change as well. If not, it is fine.

Please make sure if the test can't be run because of unmet dependencies, the test
will exit with KSFT_SKIP as opposed to an error. Dependencies include configuration,
privilege, any other unsupported conditions.

This is a comment applies to all the test patches in this series.

thanks,
-- Shuah

Patch
diff mbox series

diff --git a/tools/testing/selftests/timens/.gitignore b/tools/testing/selftests/timens/.gitignore
new file mode 100644
index 000000000000..27a693229ce1
--- /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 000000000000..b877efb78974
--- /dev/null
+++ b/tools/testing/selftests/timens/Makefile
@@ -0,0 +1,5 @@ 
+TEST_GEN_PROGS := timens
+
+CFLAGS := -Wall -Werror
+
+include ../lib.mk
diff --git a/tools/testing/selftests/timens/config b/tools/testing/selftests/timens/config
new file mode 100644
index 000000000000..4480620f6f49
--- /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 000000000000..05fec7f97870
--- /dev/null
+++ b/tools/testing/selftests/timens/log.h
@@ -0,0 +1,21 @@ 
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#ifndef __SELFTEST_TIMENS_LOG_H__
+#define __SELFTEST_TIMENS_LOG_H__
+
+#define pr_msg(fmt, lvl, ...)						\
+	fprintf(stderr, "[%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, ...)						\
+	({								\
+		pr_msg(fmt, "ERR", ##__VA_ARGS__)			\
+		-1;							\
+	})
+#define pr_fail(fmt, ...)	pr_msg(fmt, "FAIL", ##__VA_ARGS__)
+
+#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 000000000000..dfa6701214b1
--- /dev/null
+++ b/tools/testing/selftests/timens/timens.c
@@ -0,0 +1,196 @@ 
+// 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 "log.h"
+
+#ifndef CLONE_NEWTIME
+# define CLONE_NEWTIME	0x00001000
+#endif
+
+/*
+ * 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]))
+
+#define CLOCK_TYPES							\
+	ct(CLOCK_BOOTTIME),						\
+	ct(CLOCK_MONOTONIC),						\
+	ct(CLOCK_MONOTONIC_COARSE),					\
+	ct(CLOCK_MONOTONIC_RAW),					\
+
+
+#define ct(clock)	clock
+static clockid_t clocks[] = {
+	CLOCK_TYPES
+};
+#undef ct
+#define ct(clock)	#clock
+static char *clock_names[] = {
+	CLOCK_TYPES
+};
+
+static int child_ns, parent_ns;
+
+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";
+	struct stat st1, st2;
+
+	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(CLONE_NEWTIME))
+		return pr_perror("Can't unshare() timens");
+
+	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 _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 int _settime(clockid_t clk_id, struct timespec *res, bool raw_syscall)
+{
+	int err;
+
+	if (!raw_syscall) {
+		if (clock_settime(clk_id, res))
+			return pr_perror("clock_settime(%d)", (int)clk_id);
+		return 0;
+	}
+
+	err = syscall(SYS_clock_settime, clk_id, res);
+	if (err)
+		pr_perror("syscall(SYS_clock_settime(%d))", (int)clk_id);
+
+	return err;
+}
+
+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;
+
+	switch (clocks[clock_index]) {
+	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], &parent_ts_old, raw_syscall))
+		return -1;
+
+	if (switch_ns(child_ns))
+		return pr_err("switch_ns(%d)", child_ns);
+
+	child_ts_new.tv_nsec = parent_ts_old.tv_nsec;
+	child_ts_new.tv_sec = parent_ts_old.tv_sec + offset;
+
+	if (_settime(clocks[clock_index], &child_ts_new, raw_syscall))
+		return -1;
+
+	if (_gettime(clocks[clock_index], &cur_ts, raw_syscall))
+		return -1;
+
+	if (difftime(cur_ts.tv_sec, child_ts_new.tv_sec) < precision) {
+		pr_fail("Child's %s (%s) time has not changed: %lu -> %lu [%lu]",
+			clock_names[clock_index], 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], &cur_ts, raw_syscall))
+		return -1;
+
+	if (difftime(cur_ts.tv_sec, parent_ts_old.tv_sec) > DAY_IN_SEC) {
+		pr_fail("Parent's %s (%s) time has changed: %lu -> %lu [%lu]",
+			clock_names[clock_index], 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], &cur_ts);
+		return -1;
+	}
+
+	pr_msg("Passed for %s (%s)", "OK", clock_names[clock_index], entry);
+	return 0;
+}
+
+int main(int argc, char *argv[])
+{
+	unsigned int i;
+	int ret = 0;
+
+	if (init_namespaces())
+		return 1;
+
+	for (i = 0; i < ARRAY_SIZE(clocks); i++) {
+		ret |= test_gettime(i, true, TEN_DAYS_IN_SEC);
+		ret |= test_gettime(i, true, -TEN_DAYS_IN_SEC);
+		ret |= test_gettime(i, false, TEN_DAYS_IN_SEC);
+		ret |= test_gettime(i, false, -TEN_DAYS_IN_SEC);
+	}
+
+	return !!ret;
+}