[PATCH 1/6] x86_64: Enable arch-generic vsyscall support.

john stultz
2006-09-07T02:18:53Z

Provides generic infrastructure for vsyscall-gtod.

Signed-off-by: John Stultz <johnstul@us.ibm.com>

include/linux/clocksource.h | 8 ++++++++
include/linux/time.h | 1 +
kernel/timer.c | 1 +
3 files changed, 10 insertions(+)

linux-2.6.18-rc6_timeofday-vsyscall-support_C6.patch
============================================
diff --git a/include/linux/clocksource.h b/include/linux/clocksource.h
index d852024..cd4d514 100644
--- a/include/linux/clocksource.h
+++ b/include/linux/clocksource.h
@@ -46,6 +46,7 @@ typedef u64 cycle_t;
* @shift: cycle to nanosecond divisor (power of two)
* @update_callback: called when safe to alter clocksource values
* @is_continuous: defines if clocksource is free-running.
+ * @vread: vsyscall based read
* @cycle_interval: Used internally by timekeeping core, please ignore.
* @xtime_interval: Used internally by timekeeping core, please ignore.
*/
@@ -59,6 +60,7 @@ struct clocksource {
u32 shift;
int (*update_callback)(void);
int is_continuous;
+ cycle_t (*vread)(void);

/* timekeeping specific data, ignore */
cycle_t cycle_last, cycle_interval;
@@ -182,4 +184,10 @@ int clocksource_register(struct clocksou
void clocksource_reselect(void);
struct clocksource* clocksource_get_next(void);

+#ifdef CONFIG_GENERIC_TIME_VSYSCALL
+extern void update_vsyscall(struct timespec* ts, struct clocksource* c);
+#else
+#define update_vsyscall(now, c) do { } while(0)
+#endif
+
#endif /* _LINUX_CLOCKSOURCE_H */
diff --git a/include/linux/time.h b/include/linux/time.h
index a5b7399..14e12f0 100644
--- a/include/linux/time.h
+++ b/include/linux/time.h
@@ -174,6 +174,7 @@ static inline void timespec_add_ns(struc
}
a->tv_nsec = ns;
}
+
#endif /* __KERNEL__ */

#define NFDBITS __NFDBITS
diff --git a/kernel/timer.c b/kernel/timer.c
index 1d7dd62..a444016 100644
--- a/kernel/timer.c
+++ b/kernel/timer.c
@@ -1165,6 +1165,7 @@ static void update_wall_time(void)
clock->xtime_nsec = 0;
clocksource_calculate_interval(clock, tick_nsec);
}
+ update_vsyscall(&xtime, clock);
}

/*