Hi all,
I've BCC'd a number of people who have reported seeing this bug at
various times in the past.
If you can still repro I'd appreciate it if you could give the patch in
http://marc.info/?l=xen-devel&m=135049062216685&w=2 (also attached) a go
and report back success/failure and the output of the debugging messages
produced.
Thanks,
Ian.
--
Ian Campbell
Current Noise: Death - Evil Dead
Executive ability is prominent in your make-up.
diff -r c1c549c4fe9e xen/arch/x86/time.c
--- a/xen/arch/x86/time.c Mon Oct 15 16:51:44 2012 +0100
+++ b/xen/arch/x86/time.c Wed Oct 17 17:13:22 2012 +0100
@@ -523,11 +523,12 @@ static s_time_t __read_platform_stime(u6
static void plt_overflow(void *unused)
{
int i;
- u64 count;
+ u64 count, old_stamp, tsc;
s_time_t now, plt_now, plt_wrap;
spin_lock_irq(&platform_timer_lock);
+ old_stamp = plt_stamp;
count = plt_src.read_counter();
plt_stamp64 += (count - plt_stamp) & plt_mask;
plt_stamp = count;
@@ -540,6 +541,14 @@ static void plt_overflow(void *unused)
plt_wrap = __read_platform_stime(plt_stamp64 + plt_mask + 1);
if ( ABS(plt_wrap - now) > ABS(plt_now - now) )
break;
+ rdtscll(tsc);
+ printk("XXX plt_overflow: plt_now=%"PRIx64" plt_wrap=%"PRIx64
+ " now=%"PRIx64" old_stamp=%"PRIx64" new_stamp=%"PRIx64
+ " plt_stamp64=%"PRIx64" plt_mask=%"PRIx64
+ " tsc=%"PRIx64" tsc_stamp=%"PRIx64"\n",
+ plt_now, plt_wrap, now, old_stamp, plt_stamp, plt_stamp64,
+ plt_mask, tsc, this_cpu(cpu_time).local_tsc_stamp);
+ break;
plt_stamp64 += plt_mask + 1;
}
if ( i != 0 )
