Re: 2.6.14-rc4-rt7

[Ingo Molnar]

* Daniel Walker <dwalker@xxxxxxxxxx> wrote:

> > > I found this latency ~5 minutes after boot up, no load . It looks like 
> > > vgacon_scroll() has a memset like operation which can grow.
> > 
> > do you have PRINTK_IGNORE_LOGLEVEL enabled? If yes then much of the 
> > printk code will run with interrupts disabled - hence non-preemptable.  
> > PRINTK_IGNORE_LOGLEVEL is a debugging feature for developers. I have 
> > added an extra explanation to the Kconfig, see below.
> 
> I was just running a "make defconfig" and I enabled latency tracing . 
> PRINTK_IGNORE_LOGLEVEL defaults to off (doesn't it?), and I didn't 
> make any changes to it . Unless it get switched on by something else 
> ..
> 
> It looks like the logic might be reversed in release_console_sem() .

yeah, it is reversed. I 'fixed' it a couple of releases ago - but in 
fact it was correct previously and i introduced this bug. I have fixed 
this in my tree and have released -rt9 with the fix. 

	Ingo
-
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/