Re: [Xen-devel] [PATCH 3/4] x86/nmi: wait for all CPUs in check_nmi_watchdog()

[Tim Deegan <tim@xxxxxxx>]

At 13:58 +0100 on 14 May (1400072298), David Vrabel wrote:
> The counting of a CPUs NMIs in check_nmi_watchdog() is only reliable
> if all CPUs have been spinning for 5 or more ticks.  There may be
> delays in waking other CPUs from deep power states that can mean that
> when the counts are checked CPUs haven't run for long enough.
> 
> Fix this by waiting for all CPUs to have delayed in wait_for_nmis().
> 
> Signed-off-by: David Vrabel <david.vrabel@xxxxxxxxxx>

Reviewed-by: Tim Deegan <tim@xxxxxxx>

I think we could separately address the boot time issue by having
wait_for_nmis() exit after it's seen 5 NMIs _or_ counted 10 ticks.

Tim.

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxx
http://lists.xen.org/xen-devel