Re: 2.6.16-rc6-rt7

From: Thomas Gleixner
Date: Thu Mar 16 2006 - 12:47:36 EST


On Thu, 2006-03-16 at 09:39 -0800, David Brown wrote:
> I've been having issues with the realtime patch set and using scp
> (specifically scp, wget, curl, git, cvs everything else works fine). I
> was wondering what extra debugging features are helpful to have built
> into the kernel that could help me nail down why this bug is
> happening.
>
> Specifically what's happening is scp is freezing my system, there
> haven't been any kernel warnings or panics upon execution of scp, it
> just freezes, every other application that uses network seems to work
> just fine, so far it's just been scp.

Just found a problem in the highres timer merge. Can you try the patch
below?

tglx

Index: linux-2.6.16-rc6/include/linux/hrtimer.h
===================================================================
--- linux-2.6.16-rc6.orig/include/linux/hrtimer.h
+++ linux-2.6.16-rc6/include/linux/hrtimer.h
@@ -114,6 +114,8 @@ extern void hrtimer_clock_notify(void);
extern void clock_was_set(void);
extern int hrtimer_interrupt(void);

+#define hrtimer_cb_get_time(t) (t)->base->get_time()
+
/*
* The resolution of the clocks. The resolution value is returned in
* the clock_getres() system call to give application programmers an
@@ -136,6 +138,8 @@ extern int hrtimer_interrupt(void);
#define clock_was_set() do { } while (0)
#define hrtimer_clock_notify() do { } while (0)

+#define hrtimer_cb_get_time(t) (t)->base->softirq_time
+
#endif

# if (BITS_PER_LONG == 64) || defined(CONFIG_KTIME_SCALAR)
Index: linux-2.6.16-rc6/kernel/hrtimer.c
===================================================================
--- linux-2.6.16-rc6.orig/kernel/hrtimer.c
+++ linux-2.6.16-rc6/kernel/hrtimer.c
@@ -970,8 +970,6 @@ static inline void run_hrtimer_hres_queu
{
spin_lock_irq(&base->lock);

- base->softirq_time = base->get_softirq_time();
-
while (!list_empty(&base->cb_pending)) {
struct hrtimer *timer;
int (*fn)(struct hrtimer *);
Index: linux-2.6.16-rc6/kernel/itimer.c
===================================================================
--- linux-2.6.16-rc6.orig/kernel/itimer.c
+++ linux-2.6.16-rc6/kernel/itimer.c
@@ -136,7 +136,7 @@ int it_real_fn(struct hrtimer *timer)
send_group_sig_info(SIGALRM, SEND_SIG_PRIV, sig->tsk);

if (sig->it_real_incr.tv64 != 0) {
- hrtimer_forward(timer, timer->base->softirq_time,
+ hrtimer_forward(timer, hrtimer_cb_get_time(timer),
sig->it_real_incr);
return HRTIMER_RESTART;
}
Index: linux-2.6.16-rc6/kernel/posix-timers.c
===================================================================
--- linux-2.6.16-rc6.orig/kernel/posix-timers.c
+++ linux-2.6.16-rc6/kernel/posix-timers.c
@@ -355,9 +355,10 @@ static int posix_timer_fn(struct hrtimer
if (timr->it.real.interval.tv64 != 0) {
timr->it_overrun +=
hrtimer_forward(timer,
- timer->base->softirq_time,
+ hrtimer_cb_get_time(timer),
timr->it.real.interval);
ret = HRTIMER_RESTART;
+ ++timr->it_requeue_pending;
}
}



-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/