Re: [PATCH 0/1] speeding up cpu_up()
From: Ingo Molnar
Date: Mon Apr 20 2015 - 03:16:07 EST
* Len Brown <lenb@xxxxxxxxxx> wrote:
> The following patch...
>
> [PATCH 1/1] x86: replace cpu_up hard-coded mdelay with variable
>
> enables reducing cpu_up() time by 10ms on modern systems.
>
> This means that for every processor in the system,
> boot-time and resume-time can be reduced by 10ms per-processor.
>
> Once this patch is accepted, I'll send a subsequent patch
> to update the default delay, as appropriate.
>
> thanks,
> Len Brown, Intel Open Source Technology Center
So instead of playing games with an ancient delay, I'd suggest we
install the 10 msec INIT assertion wait as a platform quirk instead,
and activate it for all CPUs/systems that we think might need it, with
a sufficiently robust and future-proof quirk cutoff condition.
New systems won't have the quirk active and thus won't have to have
this delay configurable either.
Thanks,
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/