Test that btime value of /proc/stat is as expected in the time namespace
using a simple parser to get btime from /proc/stat.
Signed-off-by: Michael Weiß <michael.we...@aisec.fraunhofer.de>
---
tools/testing/selftests/timens/procfs.c | 58 ++++++++++++++++++++++++-
1 file changed, 57 insertions(+), 1 deletion(-)
diff --git a/tools/testing/selftests/timens/procfs.c
b/tools/testing/selftests/timens/procfs.c
index 7f14f0fdac84..f2519154208a 100644
--- a/tools/testing/selftests/timens/procfs.c
+++ b/tools/testing/selftests/timens/procfs.c
@@ -93,6 +93,33 @@ static int read_proc_uptime(struct timespec *uptime)
return 0;
}
+static int read_proc_stat_btime(unsigned long long *boottime_sec)
+{
+ FILE *proc;
+ char line_buf[2048];
+
+ proc = fopen("/proc/stat", "r");
+ if (proc == NULL) {
+ pr_perror("Unable to open /proc/stat");
+ return -1;
+ }
+
+ while (fgets(line_buf, 2048, proc)) {
+ if (sscanf(line_buf, "btime %llu", boottime_sec) != 1)
+ continue;
+ fclose(proc);
+ return 0;
+ }
+ if (errno) {
+ pr_perror("fscanf");
+ fclose(proc);
+ return -errno;
+ }
+ pr_err("failed to parse /proc/stat");
+ fclose(proc);
+ return -1;
+}
+
static int check_uptime(void)
{
struct timespec uptime_new, uptime_old;
@@ -123,18 +150,47 @@ static int check_uptime(void)
return 0;
}
+static int check_stat_btime(void)
+{
+ unsigned long long btime_new, btime_old;
+ unsigned long long btime_expected;
+
+ if (switch_ns(parent_ns))
+ return pr_err("switch_ns(%d)", parent_ns);
+
+ if (read_proc_stat_btime(&btime_old))
+ return 1;
+
+ if (switch_ns(child_ns))
+ return pr_err("switch_ns(%d)", child_ns);
+
+ if (read_proc_stat_btime(&btime_new))
+ return 1;
+
+ btime_expected = btime_old - TEN_DAYS_IN_SEC;
+ if (btime_new != btime_expected) {
+ pr_fail("btime in /proc/stat: old %llu, new %llu [%llu]",
+ btime_old, btime_new, btime_expected);
+ return 1;
+ }
+
+ ksft_test_result_pass("Passed for /proc/stat btime\n");
+ return 0;
+}
+
int main(int argc, char *argv[])
{
int ret = 0;
nscheck();
- ksft_set_plan(1);
+ ksft_set_plan(2);
if (init_namespaces())
return 1;
ret |= check_uptime();
+ ret |= check_stat_btime();
if (ret)
ksft_exit_fail();
--
2.20.1
