Re: [Xen-devel] [PATCH v2 11/11] xen: credit2: implement true SMT support

2016-07-19 Thread Dario Faggioli
On Tue, 2016-07-19 at 11:05 +0100, George Dunlap wrote: > On 19/07/16 10:57, Dario Faggioli wrote: > >  > > > What about folding in something like the attached patch? > > > > > I'd be totally fine with this. > Do you mean you ack me folding in that particular patch (so that the > resulting commit

Re: [Xen-devel] [PATCH v2 11/11] xen: credit2: implement true SMT support

2016-07-19 Thread George Dunlap
On 19/07/16 10:57, Dario Faggioli wrote: > On Tue, 2016-07-19 at 10:39 +0100, George Dunlap wrote: >> On Mon, Jul 18, 2016 at 6:24 PM, Dario Faggioli >> wrote: >>> >>> If you're saying that this discrepancy between rqd->idle's and >>> rqd->smt_idle's semantic is, at minimum, unideal, I do agree.

Re: [Xen-devel] [PATCH v2 11/11] xen: credit2: implement true SMT support

2016-07-19 Thread Dario Faggioli
On Tue, 2016-07-19 at 10:39 +0100, George Dunlap wrote: > On Mon, Jul 18, 2016 at 6:24 PM, Dario Faggioli > wrote: > >  > > If you're saying that this discrepancy between rqd->idle's and > > rqd->smt_idle's semantic is, at minimum, unideal, I do agree... but > > I > > think, for now at least, it's

Re: [Xen-devel] [PATCH v2 11/11] xen: credit2: implement true SMT support

2016-07-19 Thread George Dunlap
On Mon, Jul 18, 2016 at 6:24 PM, Dario Faggioli wrote: > On Mon, 2016-07-18 at 17:48 +0100, George Dunlap wrote: >> On 15/07/16 15:50, Dario Faggioli wrote: >> > >> > +/* >> > + * If all the siblings of cpu (including cpu itself) are in >> > idlers, >> > + * set all their bits in mask. >> > + * >>

Re: [Xen-devel] [PATCH v2 11/11] xen: credit2: implement true SMT support

2016-07-18 Thread Dario Faggioli
On Mon, 2016-07-18 at 17:48 +0100, George Dunlap wrote: > On 15/07/16 15:50, Dario Faggioli wrote: > >  > > +/* > > + * If all the siblings of cpu (including cpu itself) are in > > idlers, > > + * set all their bits in mask. > > + * > > + * In order to properly take into account tickling, idlers ne

Re: [Xen-devel] [PATCH v2 11/11] xen: credit2: implement true SMT support

2016-07-18 Thread George Dunlap
On 15/07/16 15:50, Dario Faggioli wrote: > In fact, right now, we recommend keepeing runqueues > arranged per-core, so that it is the inter-runqueue load > balancing code that automatically spreads the work in an > SMT friendly way. This means that any other runq > arrangement one may want to use f