[CRIU] [PATCHv3 03/27] timens: Introduce CLOCK_MONOTONIC offsets
Dmitry Safonov
dima at arista.com
Thu Apr 25 19:13:52 MSK 2019
From: Andrei Vagin <avagin at openvz.org>
Add monotonic time virtualisation for time namespace.
Introduce timespec for monotionic clock into timens offsets and wire
clock_gettime() syscall.
Signed-off-by: Andrei Vagin <avagin at openvz.org>
Co-developed-by: Dmitry Safonov <dima at arista.com>
Signed-off-by: Dmitry Safonov <dima at arista.com>
---
include/linux/time_namespace.h | 8 ++++++++
include/linux/timens_offsets.h | 1 +
include/uapi/linux/time.h | 2 ++
kernel/time/posix-stubs.c | 2 ++
kernel/time/posix-timers.c | 11 +++++++++--
5 files changed, 22 insertions(+), 2 deletions(-)
diff --git a/include/linux/time_namespace.h b/include/linux/time_namespace.h
index b6985aa87479..8f75d34cf34a 100644
--- a/include/linux/time_namespace.h
+++ b/include/linux/time_namespace.h
@@ -40,6 +40,13 @@ static inline void put_time_ns(struct time_namespace *ns)
kref_put(&ns->kref, free_time_ns);
}
+static inline void timens_add_monotonic(struct timespec64 *ts)
+{
+ struct timens_offsets *ns_offsets = current->nsproxy->time_ns->offsets;
+
+ if (ns_offsets)
+ *ts = timespec64_add(*ts, ns_offsets->monotonic_time_offset);
+}
#else
static inline struct time_namespace *get_time_ns(struct time_namespace *ns)
@@ -65,6 +72,7 @@ static inline int timens_on_fork(struct nsproxy *nsproxy, struct task_struct *ts
return 0;
}
+static inline void timens_add_monotonic(struct timespec64 *ts) {}
#endif
#endif /* _LINUX_TIMENS_H */
diff --git a/include/linux/timens_offsets.h b/include/linux/timens_offsets.h
index 7d7cb68ea778..248b0c0bb92a 100644
--- a/include/linux/timens_offsets.h
+++ b/include/linux/timens_offsets.h
@@ -3,6 +3,7 @@
#define _LINUX_TIME_OFFSETS_H
struct timens_offsets {
+ struct timespec64 monotonic_time_offset;
};
#endif
diff --git a/include/uapi/linux/time.h b/include/uapi/linux/time.h
index 958932effc5e..32abadc68f72 100644
--- a/include/uapi/linux/time.h
+++ b/include/uapi/linux/time.h
@@ -65,6 +65,8 @@ struct itimerval {
#define CLOCKS_MASK (CLOCK_REALTIME | CLOCK_MONOTONIC)
#define CLOCKS_MONO CLOCK_MONOTONIC
+#define CLOCK_TIMENS 1024
+
/*
* The various flags for setting POSIX.1b interval timers:
*/
diff --git a/kernel/time/posix-stubs.c b/kernel/time/posix-stubs.c
index 67df65f887ac..17c67e0aecd8 100644
--- a/kernel/time/posix-stubs.c
+++ b/kernel/time/posix-stubs.c
@@ -14,6 +14,7 @@
#include <linux/ktime.h>
#include <linux/timekeeping.h>
#include <linux/posix-timers.h>
+#include <linux/time_namespace.h>
#include <linux/compat.h>
#ifdef CONFIG_ARCH_HAS_SYSCALL_WRAPPER
@@ -77,6 +78,7 @@ int do_clock_gettime(clockid_t which_clock, struct timespec64 *tp)
break;
case CLOCK_MONOTONIC:
ktime_get_ts64(tp);
+ timens_add_monotonic(tp);
break;
case CLOCK_BOOTTIME:
ktime_get_boottime_ts64(tp);
diff --git a/kernel/time/posix-timers.c b/kernel/time/posix-timers.c
index 29176635991f..a047d6b7c768 100644
--- a/kernel/time/posix-timers.c
+++ b/kernel/time/posix-timers.c
@@ -30,6 +30,7 @@
#include <linux/hashtable.h>
#include <linux/compat.h>
#include <linux/nospec.h>
+#include <linux/time_namespace.h>
#include "timekeeping.h"
#include "posix-timers.h"
@@ -190,6 +191,8 @@ static int posix_clock_realtime_adj(const clockid_t which_clock,
static int posix_ktime_get_ts(clockid_t which_clock, struct timespec64 *tp)
{
ktime_get_ts64(tp);
+ if (which_clock & CLOCK_TIMENS)
+ timens_add_monotonic(tp);
return 0;
}
@@ -199,6 +202,8 @@ static int posix_ktime_get_ts(clockid_t which_clock, struct timespec64 *tp)
static int posix_get_monotonic_raw(clockid_t which_clock, struct timespec64 *tp)
{
ktime_get_raw_ts64(tp);
+ if (which_clock & CLOCK_TIMENS)
+ timens_add_monotonic(tp);
return 0;
}
@@ -213,6 +218,8 @@ static int posix_get_monotonic_coarse(clockid_t which_clock,
struct timespec64 *tp)
{
ktime_get_coarse_ts64(tp);
+ if (which_clock & CLOCK_TIMENS)
+ timens_add_monotonic(tp);
return 0;
}
@@ -1039,7 +1046,7 @@ SYSCALL_DEFINE2(clock_gettime, const clockid_t, which_clock,
if (!kc)
return -EINVAL;
- error = kc->clock_get(which_clock, &kernel_tp);
+ error = kc->clock_get(which_clock | CLOCK_TIMENS, &kernel_tp);
if (!error && put_timespec64(&kernel_tp, tp))
error = -EFAULT;
@@ -1121,7 +1128,7 @@ SYSCALL_DEFINE2(clock_gettime32, clockid_t, which_clock,
if (!kc)
return -EINVAL;
- err = kc->clock_get(which_clock, &ts);
+ err = kc->clock_get(which_clock | CLOCK_TIMENS, &ts);
if (!err && put_old_timespec32(&ts, tp))
err = -EFAULT;
--
2.21.0
More information about the CRIU
mailing list