selftests/timers: Add leapcrash test from the timetest suite
authorJohn Stultz <john.stultz@linaro.org>
Thu, 12 Mar 2015 00:40:12 +0000 (17:40 -0700)
committerShuah Khan <shuahkh@osg.samsung.com>
Thu, 12 Mar 2015 19:22:16 +0000 (13:22 -0600)
This change adds the leapcrash test which tests to see if a
leapsecond deadlock which was observed from 2.6.26 to 3.3
is present on this system.

Cc: Shuah Khan <shuahkh@osg.samsung.com>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Tested-by: Prarit Bhargava <prarit@redhat.com>
Signed-off-by: Shuah Khan <shuahkh@osg.samsung.com>
tools/testing/selftests/timers/Makefile
tools/testing/selftests/timers/leapcrash.c [new file with mode: 0644]

index da35ddd..d733324 100644 (file)
@@ -5,7 +5,7 @@ LDFLAGS += -lrt -lpthread
 bins = posix_timers nanosleep inconsistency-check nsleep-lat raw_skew \
        set-timer-lat threadtest mqueue-lat valid-adjtimex \
        alarmtimer-suspend change_skew skew_consistency clocksource-switch \
-       leap-a-day
+       leap-a-day leapcrash
 
 all: ${bins}
 
@@ -31,6 +31,7 @@ run_destructive_tests: run_tests
        ./skew_consistency
        ./clocksource-switch
        ./leap-a-day -s -i 10
+       ./leapcrash
 
 clean:
        rm -f ${bins}
diff --git a/tools/testing/selftests/timers/leapcrash.c b/tools/testing/selftests/timers/leapcrash.c
new file mode 100644 (file)
index 0000000..a1071bd
--- /dev/null
@@ -0,0 +1,120 @@
+/* Demo leapsecond deadlock
+ *              by: John Stultz (john.stultz@linaro.org)
+ *              (C) Copyright IBM 2012
+ *              (C) Copyright 2013, 2015 Linaro Limited
+ *              Licensed under the GPL
+ *
+ * This test demonstrates leapsecond deadlock that is possibe
+ * on kernels from 2.6.26 to 3.3.
+ *
+ * WARNING: THIS WILL LIKELY HARDHANG SYSTEMS AND MAY LOSE DATA
+ * RUN AT YOUR OWN RISK!
+ *  To build:
+ *     $ gcc leapcrash.c -o leapcrash -lrt
+ */
+
+
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <time.h>
+#include <sys/time.h>
+#include <sys/timex.h>
+#include <string.h>
+#include <signal.h>
+#ifdef KTEST
+#include "../kselftest.h"
+#else
+static inline int ksft_exit_pass(void)
+{
+       exit(0);
+}
+static inline int ksft_exit_fail(void)
+{
+       exit(1);
+}
+#endif
+
+
+
+/* clear NTP time_status & time_state */
+int clear_time_state(void)
+{
+       struct timex tx;
+       int ret;
+
+       /*
+        * We have to call adjtime twice here, as kernels
+        * prior to 6b1859dba01c7 (included in 3.5 and
+        * -stable), had an issue with the state machine
+        * and wouldn't clear the STA_INS/DEL flag directly.
+        */
+       tx.modes = ADJ_STATUS;
+       tx.status = STA_PLL;
+       ret = adjtimex(&tx);
+
+       tx.modes = ADJ_STATUS;
+       tx.status = 0;
+       ret = adjtimex(&tx);
+
+       return ret;
+}
+
+/* Make sure we cleanup on ctrl-c */
+void handler(int unused)
+{
+       clear_time_state();
+       exit(0);
+}
+
+
+int main(void)
+{
+       struct timex tx;
+       struct timespec ts;
+       time_t next_leap;
+       int count = 0;
+
+       setbuf(stdout, NULL);
+
+       signal(SIGINT, handler);
+       signal(SIGKILL, handler);
+       printf("This runs for a few minutes. Press ctrl-c to stop\n");
+
+       clear_time_state();
+
+
+       /* Get the current time */
+       clock_gettime(CLOCK_REALTIME, &ts);
+
+       /* Calculate the next possible leap second 23:59:60 GMT */
+       next_leap = ts.tv_sec;
+       next_leap += 86400 - (next_leap % 86400);
+
+       for (count = 0; count < 20; count++) {
+               struct timeval tv;
+
+
+               /* set the time to 2 seconds before the leap */
+               tv.tv_sec = next_leap - 2;
+               tv.tv_usec = 0;
+               if (settimeofday(&tv, NULL)) {
+                       printf("Error: You're likely not running with proper (ie: root) permissions\n");
+                       return ksft_exit_fail();
+               }
+               tx.modes = 0;
+               adjtimex(&tx);
+
+               /* hammer on adjtime w/ STA_INS */
+               while (tx.time.tv_sec < next_leap + 1) {
+                       /* Set the leap second insert flag */
+                       tx.modes = ADJ_STATUS;
+                       tx.status = STA_INS;
+                       adjtimex(&tx);
+               }
+               clear_time_state();
+               printf(".");
+       }
+       printf("[OK]\n");
+       return ksft_exit_pass();
+}