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-rw-r--r--arch/x86/include/asm/vgtod.h1
-rw-r--r--arch/x86/kernel/vsyscall_64.c1
-rw-r--r--arch/x86/vdso/vclock_gettime.c39
-rw-r--r--include/linux/time.h4
-rw-r--r--kernel/posix-timers.c35
-rw-r--r--kernel/time/timekeeping.c21
6 files changed, 98 insertions, 3 deletions
diff --git a/arch/x86/include/asm/vgtod.h b/arch/x86/include/asm/vgtod.h
index dc27a69e5d2..3d61e204826 100644
--- a/arch/x86/include/asm/vgtod.h
+++ b/arch/x86/include/asm/vgtod.h
@@ -21,6 +21,7 @@ struct vsyscall_gtod_data {
u32 shift;
} clock;
struct timespec wall_to_monotonic;
+ struct timespec wall_time_coarse;
};
extern struct vsyscall_gtod_data __vsyscall_gtod_data
__section_vsyscall_gtod_data;
diff --git a/arch/x86/kernel/vsyscall_64.c b/arch/x86/kernel/vsyscall_64.c
index 25ee06a80aa..cf53a78e2dc 100644
--- a/arch/x86/kernel/vsyscall_64.c
+++ b/arch/x86/kernel/vsyscall_64.c
@@ -87,6 +87,7 @@ void update_vsyscall(struct timespec *wall_time, struct clocksource *clock)
vsyscall_gtod_data.wall_time_sec = wall_time->tv_sec;
vsyscall_gtod_data.wall_time_nsec = wall_time->tv_nsec;
vsyscall_gtod_data.wall_to_monotonic = wall_to_monotonic;
+ vsyscall_gtod_data.wall_time_coarse = __current_kernel_time();
write_sequnlock_irqrestore(&vsyscall_gtod_data.lock, flags);
}
diff --git a/arch/x86/vdso/vclock_gettime.c b/arch/x86/vdso/vclock_gettime.c
index 6a40b78b46a..ee55754cc3c 100644
--- a/arch/x86/vdso/vclock_gettime.c
+++ b/arch/x86/vdso/vclock_gettime.c
@@ -86,14 +86,47 @@ notrace static noinline int do_monotonic(struct timespec *ts)
return 0;
}
+notrace static noinline int do_realtime_coarse(struct timespec *ts)
+{
+ unsigned long seq;
+ do {
+ seq = read_seqbegin(&gtod->lock);
+ ts->tv_sec = gtod->wall_time_coarse.tv_sec;
+ ts->tv_nsec = gtod->wall_time_coarse.tv_nsec;
+ } while (unlikely(read_seqretry(&gtod->lock, seq)));
+ return 0;
+}
+
+notrace static noinline int do_monotonic_coarse(struct timespec *ts)
+{
+ unsigned long seq, ns, secs;
+ do {
+ seq = read_seqbegin(&gtod->lock);
+ secs = gtod->wall_time_coarse.tv_sec;
+ ns = gtod->wall_time_coarse.tv_nsec;
+ secs += gtod->wall_to_monotonic.tv_sec;
+ ns += gtod->wall_to_monotonic.tv_nsec;
+ } while (unlikely(read_seqretry(&gtod->lock, seq)));
+ vset_normalized_timespec(ts, secs, ns);
+ return 0;
+}
+
notrace int __vdso_clock_gettime(clockid_t clock, struct timespec *ts)
{
- if (likely(gtod->sysctl_enabled && gtod->clock.vread))
+ if (likely(gtod->sysctl_enabled))
switch (clock) {
case CLOCK_REALTIME:
- return do_realtime(ts);
+ if (likely(gtod->clock.vread))
+ return do_realtime(ts);
+ break;
case CLOCK_MONOTONIC:
- return do_monotonic(ts);
+ if (likely(gtod->clock.vread))
+ return do_monotonic(ts);
+ break;
+ case CLOCK_REALTIME_COARSE:
+ return do_realtime_coarse(ts);
+ case CLOCK_MONOTONIC_COARSE:
+ return do_monotonic_coarse(ts);
}
return vdso_fallback_gettime(clock, ts);
}
diff --git a/include/linux/time.h b/include/linux/time.h
index f505988398e..256232f7e5e 100644
--- a/include/linux/time.h
+++ b/include/linux/time.h
@@ -110,6 +110,8 @@ extern int timekeeping_suspended;
unsigned long get_seconds(void);
struct timespec current_kernel_time(void);
+struct timespec __current_kernel_time(void); /* does not hold xtime_lock */
+struct timespec get_monotonic_coarse(void);
#define CURRENT_TIME (current_kernel_time())
#define CURRENT_TIME_SEC ((struct timespec) { get_seconds(), 0 })
@@ -243,6 +245,8 @@ struct itimerval {
#define CLOCK_PROCESS_CPUTIME_ID 2
#define CLOCK_THREAD_CPUTIME_ID 3
#define CLOCK_MONOTONIC_RAW 4
+#define CLOCK_REALTIME_COARSE 5
+#define CLOCK_MONOTONIC_COARSE 6
/*
* The IDs of various hardware clocks:
diff --git a/kernel/posix-timers.c b/kernel/posix-timers.c
index d089d052c4a..495440779ce 100644
--- a/kernel/posix-timers.c
+++ b/kernel/posix-timers.c
@@ -242,6 +242,25 @@ static int posix_get_monotonic_raw(clockid_t which_clock, struct timespec *tp)
return 0;
}
+
+static int posix_get_realtime_coarse(clockid_t which_clock, struct timespec *tp)
+{
+ *tp = current_kernel_time();
+ return 0;
+}
+
+static int posix_get_monotonic_coarse(clockid_t which_clock,
+ struct timespec *tp)
+{
+ *tp = get_monotonic_coarse();
+ return 0;
+}
+
+int posix_get_coarse_res(const clockid_t which_clock, struct timespec *tp)
+{
+ *tp = ktime_to_timespec(KTIME_LOW_RES);
+ return 0;
+}
/*
* Initialize everything, well, just everything in Posix clocks/timers ;)
*/
@@ -262,10 +281,26 @@ static __init int init_posix_timers(void)
.timer_create = no_timer_create,
.nsleep = no_nsleep,
};
+ struct k_clock clock_realtime_coarse = {
+ .clock_getres = posix_get_coarse_res,
+ .clock_get = posix_get_realtime_coarse,
+ .clock_set = do_posix_clock_nosettime,
+ .timer_create = no_timer_create,
+ .nsleep = no_nsleep,
+ };
+ struct k_clock clock_monotonic_coarse = {
+ .clock_getres = posix_get_coarse_res,
+ .clock_get = posix_get_monotonic_coarse,
+ .clock_set = do_posix_clock_nosettime,
+ .timer_create = no_timer_create,
+ .nsleep = no_nsleep,
+ };
register_posix_clock(CLOCK_REALTIME, &clock_realtime);
register_posix_clock(CLOCK_MONOTONIC, &clock_monotonic);
register_posix_clock(CLOCK_MONOTONIC_RAW, &clock_monotonic_raw);
+ register_posix_clock(CLOCK_REALTIME_COARSE, &clock_realtime_coarse);
+ register_posix_clock(CLOCK_MONOTONIC_COARSE, &clock_monotonic_coarse);
posix_timers_cache = kmem_cache_create("posix_timers_cache",
sizeof (struct k_itimer), 0, SLAB_PANIC,
diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c
index 15e06defca5..03cbeb34d14 100644
--- a/kernel/time/timekeeping.c
+++ b/kernel/time/timekeeping.c
@@ -847,6 +847,10 @@ unsigned long get_seconds(void)
}
EXPORT_SYMBOL(get_seconds);
+struct timespec __current_kernel_time(void)
+{
+ return xtime_cache;
+}
struct timespec current_kernel_time(void)
{
@@ -862,3 +866,20 @@ struct timespec current_kernel_time(void)
return now;
}
EXPORT_SYMBOL(current_kernel_time);
+
+struct timespec get_monotonic_coarse(void)
+{
+ struct timespec now, mono;
+ unsigned long seq;
+
+ do {
+ seq = read_seqbegin(&xtime_lock);
+
+ now = xtime_cache;
+ mono = wall_to_monotonic;
+ } while (read_seqretry(&xtime_lock, seq));
+
+ set_normalized_timespec(&now, now.tv_sec + mono.tv_sec,
+ now.tv_nsec + mono.tv_nsec);
+ return now;
+}