Re: [Xen-devel] [PATCH v6 01/20] xen/sched: add code to sync scheduling of all vcpus of a sched unit

[Jürgen Groß <jgross@xxxxxxxx>]

On 02.10.19 09:27, 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>
> Acked-by: Jan Beulich <jbeulich@xxxxxxxx>
Julien gave is Acked-by via IRC.


Juergen

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