Re: [ANNOUNCE] 2.6.29.6-rt23

Thomas Gleixner
2009-07-10T18:30:55Z

On Fri, 10 Jul 2009, Fernando Lopez-Lezcano wrote:
> On Thu, 2009-07-09 at 20:25 +0200, Thomas Gleixner wrote:
> > We are pleased to announce the next update to our new preempt-rt
> > series.
> >
> > - update to 2.6.29.6
> >
> > - compile fixes (Wu Zhangjin)
> >
> > - powerpc highmem fix
> >
> > - hwlat smp_processor_id() fix (Carsten)
> >
> > - ktime_get* speedups (Martin)
>
> I'm getting slightly weird behavior from rt23 in an intel quad core
> machine (my T61 laptop is fine), rt22 was fine. It is some timer issue,
> if I type continuously I get (every few seconds) repeated keys. Nothing
> in the logs, nothing in dmesg that is (significantly) different from an
> rt22 boot.

Hmm. The only change which touches timer related stuff is the ktime*
speedups. Can you please apply the revert patch below and check
whether that changes anything? If not, then we need to look at the
2.6.29.5 -> .6 delta.

Thanks,

tglx
-----
diff --git b/kernel/hrtimer.c a/kernel/hrtimer.c
index 93affb0..cb8a15c 100644
--- b/kernel/hrtimer.c
+++ a/kernel/hrtimer.c
@@ -46,6 +46,37 @@

#include <asm/uaccess.h>

+/**
+ * ktime_get - get the monotonic time in ktime_t format
+ *
+ * returns the time in ktime_t format
+ */
+ktime_t ktime_get(void)
+{
+ struct timespec now;
+
+ ktime_get_ts(&now);
+
+ return timespec_to_ktime(now);
+}
+EXPORT_SYMBOL_GPL(ktime_get);
+
+/**
+ * ktime_get_real - get the real (wall-) time in ktime_t format
+ *
+ * returns the time in ktime_t format
+ */
+ktime_t ktime_get_real(void)
+{
+ struct timespec now;
+
+ getnstimeofday(&now);
+
+ return timespec_to_ktime(now);
+}
+
+EXPORT_SYMBOL_GPL(ktime_get_real);
+
/*
* The timer bases:
*
@@ -73,6 +104,31 @@ DEFINE_PER_CPU(struct hrtimer_cpu_base, hrtimer_bases) =
}
};

+/**
+ * ktime_get_ts - get the monotonic clock in timespec format
+ * @ts: pointer to timespec variable
+ *
+ * The function calculates the monotonic clock from the realtime
+ * clock and the wall_to_monotonic offset and stores the result
+ * in normalized timespec format in the variable pointed to by @ts.
+ */
+void ktime_get_ts(struct timespec *ts)
+{
+ struct timespec tomono;
+ unsigned long seq;
+
+ do {
+ seq = read_seqbegin(&xtime_lock);
+ getnstimeofday(ts);
+ tomono = wall_to_monotonic;
+
+ } while (read_seqretry(&xtime_lock, seq));
+
+ set_normalized_timespec(ts, ts->tv_sec + tomono.tv_sec,
+ ts->tv_nsec + tomono.tv_nsec);
+}
+EXPORT_SYMBOL_GPL(ktime_get_ts);
+
/*
* Get the coarse grained time at the softirq based on xtime and
* wall_to_monotonic.
diff --git b/kernel/time/timekeeping.c a/kernel/time/timekeeping.c
index 4c99c98..3192dd0 100644
--- b/kernel/time/timekeeping.c
+++ a/kernel/time/timekeeping.c
@@ -118,75 +118,6 @@ void getnstimeofday(struct timespec *ts)

EXPORT_SYMBOL(getnstimeofday);

-ktime_t ktime_get(void)
-{
- cycle_t cycle_now, cycle_delta;
- unsigned int seq;
- s64 secs, nsecs;
-
- WARN_ON(timekeeping_suspended);
-
- do {
- seq = read_seqbegin(&xtime_lock);
- secs = xtime.tv_sec + wall_to_monotonic.tv_sec;
- nsecs = xtime.tv_nsec + wall_to_monotonic.tv_nsec;
-
- /* read clocksource: */
- cycle_now = clocksource_read(clock);
-
- /* calculate the delta since the last update_wall_time: */
- cycle_delta = (cycle_now - clock->cycle_last) & clock->mask;
-
- /* convert to nanoseconds: */
- nsecs += cyc2ns(clock, cycle_delta);
-
- } while (read_seqretry(&xtime_lock, seq));
- /*
- * Use ktime_set/ktime_add_ns to create a proper ktime on
- * 32-bit architectures without CONFIG_KTIME_SCALAR.
- */
- return ktime_add_ns(ktime_set(secs, 0), nsecs);
-}
-EXPORT_SYMBOL_GPL(ktime_get);
-
-/**
- * ktime_get_ts - get the monotonic clock in timespec format
- * @ts: pointer to timespec variable
- *
- * The function calculates the monotonic clock from the realtime
- * clock and the wall_to_monotonic offset and stores the result
- * in normalized timespec format in the variable pointed to by @ts.
- */
-void ktime_get_ts(struct timespec *ts)
-{
- cycle_t cycle_now, cycle_delta;
- struct timespec tomono;
- unsigned int seq;
- s64 nsecs;
-
- WARN_ON(timekeeping_suspended);
-
- do {
- seq = read_seqbegin(&xtime_lock);
- *ts = xtime;
- tomono = wall_to_monotonic;
-
- /* read clocksource: */
- cycle_now = clocksource_read(clock);
-
- /* calculate the delta since the last update_wall_time: */
- cycle_delta = (cycle_now - clock->cycle_last) & clock->mask;
-
- /* convert to nanoseconds: */
- nsecs = cyc2ns(clock, cycle_delta);
-
- } while (read_seqretry(&xtime_lock, seq));
-
- set_normalized_timespec(ts, ts->tv_sec + tomono.tv_sec,
- ts->tv_nsec + tomono.tv_nsec + nsecs);
-}
-EXPORT_SYMBOL_GPL(ktime_get_ts);
-
/**
* do_gettimeofday - Returns the time of day in a timeval
* @tv: pointer to the timeval to be set
@@ -278,65 +209,10 @@ static void change_clocksource(void)
clock->name);
*/
}
-#else /* GENERIC_TIME */
+#else
static inline void clocksource_forward_now(void) { }
static inline void change_clocksource(void) { }
-
-/**
- * ktime_get - get the monotonic time in ktime_t format
- *
- * returns the time in ktime_t format
- */
-ktime_t ktime_get(void)
-{
- struct timespec now;
-
- ktime_get_ts(&now);
-
- return timespec_to_ktime(now);
-}
-EXPORT_SYMBOL_GPL(ktime_get);
-
-/**
- * ktime_get_ts - get the monotonic clock in timespec format
- * @ts: pointer to timespec variable
- *
- * The function calculates the monotonic clock from the realtime
- * clock and the wall_to_monotonic offset and stores the result
- * in normalized timespec format in the variable pointed to by @ts.
- */
-void ktime_get_ts(struct timespec *ts)
-{
- struct timespec tomono;
- unsigned long seq;
-
- do {
- seq = read_seqbegin(&xtime_lock);
- getnstimeofday(ts);
- tomono = wall_to_monotonic;
-
- } while (read_seqretry(&xtime_lock, seq));
-
- set_normalized_timespec(ts, ts->tv_sec + tomono.tv_sec,
- ts->tv_nsec + tomono.tv_nsec);
-}
-EXPORT_SYMBOL_GPL(ktime_get_ts);
-#endif /* !GENERIC_TIME */
-
-/**
- * ktime_get_real - get the real (wall-) time in ktime_t format
- *
- * returns the time in ktime_t format
- */
-ktime_t ktime_get_real(void)
-{
- struct timespec now;
-
- getnstimeofday(&now);