[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [Xen-devel] [PATCH 03/60] xen/sched: let sched_switch_sched() return new lock address



On Tue, 2019-05-28 at 12:32 +0200, Juergen Gross wrote:
> Instead of setting the scheduler percpu lock address in each of the
> switch_sched instances of the different schedulers do that in
> schedule_cpu_switch() which is the single caller of that function.
> For that purpose let sched_switch_sched() just return the new lock
> address.
> 
This looks good to me. The only actual functional/behavioral difference
I've been able to spot is the fact that, in Credit2, we currently
switch the lock pointer while still holding the write lock on the
global scheduler. After this change, we don't any longer.

That being said, I've tried to think about how this could be a problem,
but failed at imagining such a scenario, so:

> Signed-off-by: Juergen Gross <jgross@xxxxxxxx>
>
Reviewed-by: Dario Faggioli <dfaggioli@xxxxxxxx>

I'm wondering whether it make sense for the above to be quickly
mentioned in the changelog, but am leaning toward "not really
necessary". In particular, I don't think it's worth to respin the patch
just for that... So, either just something that can be added while
committing, or forget it.

Regards
-- 
Dario Faggioli, Ph.D
http://about.me/dario.faggioli
Virtualization Software Engineer
SUSE Labs, SUSE https://www.suse.com/
-------------------------------------------------------------------
<<This happens because _I_ choose it to happen!>> (Raistlin Majere)

Attachment: signature.asc
Description: This is a digitally signed message part

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxxx
https://lists.xenproject.org/mailman/listinfo/xen-devel

 


Rackspace

Lists.xenproject.org is hosted with RackSpace, monitoring our
servers 24x7x365 and backed by RackSpace's Fanatical Support®.