timerfd: Implement check routine

Reported-by: Jenkins
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

cr-check.c

@@ -27,6 +27,7 @@
 #include "tty.h"
 #include "ptrace.h"
 #include "kerndat.h"
+#include "timerfd.h"
 #include "tun.h"
 #include "namespaces.h"
 #include "pstree.h"
@@ -596,6 +597,7 @@ int cr_check(void)
 	ret |= check_mem_dirty_track();
 	ret |= check_posix_timers();
 	ret |= check_tun();
+	ret |= check_timerfd();
 	ret |= check_mnt_id();
 
 	if (!ret)

include/timerfd.h

@@ -26,6 +26,7 @@ static inline unsigned long rst_timerfd_len(void)
 	return sizeof(*rst_timerfd) * rst_timerfd_nr;
 }
 
+extern int check_timerfd(void);
 extern int is_timerfd_link(char *link);
 
 #ifndef TFD_TIMER_ABSTIME

timerfd.c

@@ -10,6 +10,7 @@
 
 #include "proc_parse.h"
 #include "rst-malloc.h"
+#include "cr_options.h"
 #include "restorer.h"
 #include "timerfd.h"
 #include "pstree.h"
@@ -35,6 +36,33 @@ struct timerfd_info {
 struct restore_timerfd *rst_timerfd;
 unsigned int rst_timerfd_nr;
 
+int check_timerfd(void)
+{
+	int fd, ret = -1;
+
+	if (opts.check_ms_kernel) {
+		pr_warn("Skipping timerfd support check\n");
+		return 0;
+	}
+
+	fd = timerfd_create(CLOCK_MONOTONIC, 0);
+	if (fd < 0) {
+		pr_perror("timerfd_create failed");
+		return -1;
+	} else {
+		ret = ioctl(fd, TFD_IOC_SET_TICKS, NULL);
+		if (ret < 0) {
+			if (errno != EFAULT)
+				pr_perror("No timerfd support for c/r");
+			else
+				ret = 0;
+		}
+	}
+
+	close(fd);
+	return ret;
+}
+
 int is_timerfd_link(char *link)
 {
 	return is_anon_link_type(link, "[timerfd]");