[LTP] [PATCH v2 5/9] syscalls/sysinfo03: Add time namespace test

Cyril Hrubis
2020-03-18T15:37:57Z

This tests that the uptime in sysinfo() is adjusted correctly by the
namespace offset.

Also check that /proc/uptime is consistent with the uptime from the
sysinfo() syscall.

Signed-off-by: Cyril Hrubis <chrubis@suse.cz>
---
runtest/containers | 3 +
runtest/syscalls | 1 +
testcases/kernel/syscalls/sysinfo/.gitignore | 1 +
testcases/kernel/syscalls/sysinfo/sysinfo03.c | 81 +++++++++++++++++++
4 files changed, 86 insertions(+)
create mode 100644 testcases/kernel/syscalls/sysinfo/sysinfo03.c

diff --git a/runtest/containers b/runtest/containers
index 871cd2a42..4dc05af93 100644
--- a/runtest/containers
+++ b/runtest/containers
@@ -85,3 +85,6 @@ userns04 userns04
userns05 userns05
userns06 userns06
userns07 userns07
+
+# time namespaces
+sysinfo03 sysinfo03
diff --git a/runtest/syscalls b/runtest/syscalls
index 6f2dcd82a..fb0b9e539 100644
--- a/runtest/syscalls
+++ b/runtest/syscalls
@@ -1465,6 +1465,7 @@ sysfs06 sysfs06

sysinfo01 sysinfo01
sysinfo02 sysinfo02
+sysinfo03 sysinfo03

syslog01 syslog01
syslog02 syslog02
diff --git a/testcases/kernel/syscalls/sysinfo/.gitignore b/testcases/kernel/syscalls/sysinfo/.gitignore
index aa7c26946..8ad2279a4 100644
--- a/testcases/kernel/syscalls/sysinfo/.gitignore
+++ b/testcases/kernel/syscalls/sysinfo/.gitignore
@@ -1,2 +1,3 @@
/sysinfo01
/sysinfo02
+/sysinfo03
diff --git a/testcases/kernel/syscalls/sysinfo/sysinfo03.c b/testcases/kernel/syscalls/sysinfo/sysinfo03.c
new file mode 100644
index 000000000..af1024915
--- /dev/null
+++ b/testcases/kernel/syscalls/sysinfo/sysinfo03.c
@@ -0,0 +1,81 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ Copyright (c) 2020 Cyril Hrubis <chrubis@suse.cz>
+ */
+/*
+
+ Test if CLOCK_BOOTTIME namespace offset is applied to sysinfo uptime and that
+ it's consistent with /proc/uptime as well.
+
+ After a call to unshare(CLONE_NEWTIME) a new timer namespace is created, the
+ process that has called the unshare() can adjust offsets for CLOCK_MONOTONIC
+ and CLOCK_BOOTTIME for its children by writing to the '/proc/self/timens_offsets'.
+
+ */
+
+#include <sys/sysinfo.h>
+#include "lapi/namespaces_constants.h"
+#include "tst_test.h"
+
+static int offsets[] = {
+ 10,
+ -10,
+ 3600,
+};
+
+static long read_proc_uptime(void)
+{
+ long sec, sec_rem;
+
+ SAFE_FILE_SCANF("/proc/uptime", "%li.%li", &sec, &sec_rem);
+
+ return sec + (sec_rem ? 1 : 0);
+}
+
+static void verify_sysinfo(unsigned int n)
+{
+ struct sysinfo si;
+ long uptime;
+ int off = offsets[n];
+
+ SAFE_UNSHARE(CLONE_NEWTIME);
+
+ SAFE_FILE_PRINTF("/proc/self/timens_offsets", "%d %d 0",
+ CLOCK_BOOTTIME, off);
+
+ sysinfo(&si);
+
+ uptime = si.uptime;
+
+ if (!SAFE_FORK()) {
+ sysinfo(&si);
+ long proc_uptime = read_proc_uptime();
+
+ long diff = si.uptime - uptime;
+
+ if (diff < off || diff > off + 1)
+ tst_res(TFAIL, "Wrong sysinfo uptime offset %li", diff);
+ else
+ tst_res(TPASS, "Correct sysinfo uptime offset %i", off);
+
+ if (si.uptime < proc_uptime || si.uptime > proc_uptime + 1) {
+ tst_res(TFAIL, "/proc/uptime %li differs from sysinfo %li",
+ proc_uptime, si.uptime);
+ } else {
+ tst_res(TPASS, "/proc/uptime is consistent with sysinfo");
+ }
+ }
+}
+
+static struct tst_test test = {
+ .tcnt = ARRAY_SIZE(offsets),
+ .test = verify_sysinfo,
+ .needs_root = 1,
+ .forks_child = 1,
+ .needs_kconfigs = (const char *[]) {
+ "CONFIG_TIME_NS=y"
+ }
+ .tags = (const struct tst_tag[]) {
+ {"linux-git", "ecc421e05bab"},
+ }
+};
--
2.24.1