Re: [Xen-devel] [PATCH v4 28/46] xen/sched: add code to sync scheduling of all vcpus of a sched unit

[Dario Faggioli <dfaggioli@xxxxxxxx>]

On Fri, 2019-09-27 at 09:00 +0200, Juergen Gross wrote:
> When switching sched units synchronize all vcpus of the new unit to
> be
> scheduled at the same time.
> 
> A variable sched_granularity is added which holds the number of vcpus
> per schedule unit.
> 
> As tasklets require to schedule the idle unit it is required to set
> the
> tasklet_work_scheduled parameter of do_schedule() to true if any cpu
> covered by the current schedule() call has any pending tasklet work.
> 
> For joining other vcpus of the schedule unit we need to add a new
> softirq SCHED_SLAVE_SOFTIRQ in order to have a way to initiate a
> context switch without calling the generic schedule() function
> selecting the vcpu to switch to, as we already know which vcpu we
> want to run. This has the other advantage not to loose any other
> concurrent SCHEDULE_SOFTIRQ events.
> 
> Signed-off-by: Juergen Gross <jgross@xxxxxxxx>
>
Reviewed-by: Dario Faggioli <dfaggioli@xxxxxxxx>

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