Messages in this thread | | | Date | Mon, 22 Apr 2013 10:01:36 +0200 | From | Ingo Molnar <> | Subject | Re: irq 16: nobody cared |
| |
* Borislav Petkov <bp@alien8.de> wrote:
> From 3c155e9a22036839c09d98a4acbc7e17a5a3783c Mon Sep 17 00:00:00 2001 > From: Borislav Petkov <bp@suse.de> > Date: Sun, 21 Apr 2013 23:56:15 +0200 > Subject: [PATCH] RCU: Expedite grace periods during suspend/resume > > Paul says CONFIG_RCU_FAST_NO_HZ can increase grace-period durations by a > factor of four. This, in turn, can change timings during suspend and can > delay interrupts handling, leading to "IRQ XX: nobody cared" splats and > the machine disabling those interrupt lines for no sensible reason. > > Thus, we want to temporarily switch to expedited grace periods when > suspending the box and return to normal settings when resuming. This > patch does exactly that.
Hm, this really smells like a workaround: treating the symptom, not the cause.
How can an increase in grace-periods break drivers and suspend? Do we understand exactly what happens there? If we do, can we fix that instead of tweaking the RCU timeouts?
Thanks,
Ingo
| |