Messages in this thread | | | Date | Wed, 28 Nov 2007 17:05:01 +0100 | From | Ingo Molnar <> | Subject | Re: -rt doesn't compile for UML |
| |
* Miklos Szeredi <miklos@szeredi.hu> wrote:
> > it doesnt need it - turn IRQOFF_TRACING off. > > # CONFIG_CRITICAL_IRQSOFF_TIMING is not set > > This seems to be off. > > But latency_trace.c uses irqs_disabled_flags(), which is defined in > <linux/irqflags.h> only if CONFIG_TRACE_IRQFLAGS_SUPPORT is set. > > So perhaps latency_trace.c should be using raw_irqs_disabled_flags() > instead. But UML doesn't define that either and I have no idea how to > do that, so this is still not solved yet.
irqs_disabled_flags() gives us a nonessential bit of the trace output:
_------=> CPU# / _-----=> irqs-off | / _----=> need-resched || / _---=> hardirq/softirq ||| / _--=> preempt-depth |||| / ||||| delay cmd pid ||||| time | caller \ / ||||| \ | / privoxy-12926 1.Ns1 0us : ktime_get_ts (ktime_get) privoxy-12926 1.Ns1 0us : getnstimeofday (ktime_get_ts) privoxy-12926 1.Ns1 1us : set_normalized_timespec (ktime_get_ts) privoxy-12926 1.Ns1 1us : rb_first (htb_dequeue)
it's the 'irqs-off' flag, which is 'd', 'D' or '.'.
so you can define irqs_off_flags to always-0 and you should be able to get pretty good traces still. It should have no functional impact.
Ingo - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |