lkml.org 
[lkml]   [2023]   [Mar]   [31]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
SubjectRE: [PATCH v3 1/2] cpu/smt: add a notifier to notify the SMT changes
Date
On Fri, Mar 31 2023 at 05:49, WenYou Yang wrote:

<SNIP>
Removing pointlessly copied mail headers. Please fix your email
client
</SNIP>

>> >
>> > So what do you want to have happen when someone goes and manually
>> > offlines all the SMT siblings using
>> > /sys/devices/system/cpu/cpu*/online
>> > ?
>>
>> I don't consider this situation. Any suggestions will be deeply appreciated.
>
> Hi Peter,
>
> I don't find a good method to handle this situation.
> Yes, manually offlining all the SMT sibling will get the same result of SMT disabling on the fly.
>
> Actually, the normal way to enable/disable SMT on the fly is to echo on/off > /sys/device/system/cpu/smt/control

That's the most convenient way, right.

But why do we need a kernel notifier for this, if you can do the same
with a sysfs knob for your driver?

Then user space can fiddle with SMT control in sysfs and afterwards tell
the driver that it should reconfigure.

That makes a ton more sense than this random notifier.

Thanks,

tglx

\
 
 \ /
  Last update: 2023-03-31 23:54    [W:0.044 / U:0.600 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site