Hello, On Mon, Jul 08, 2013 at 10:18:08PM +0530, Viresh Kumar wrote: > On 8 July 2013 21:27, Uwe Kleine-König <u.kleine-koenig@xxxxxxxxxxxxxx> wrote: > > On Mon, Jul 08, 2013 at 09:17:01PM +0530, Viresh Kumar wrote: > > >> Well, big LITTLE still runs an SMP kernel :) and so has this flag set. > > The 'S' is justified because cpu0 and cpu1 are of the same type? Are > > there b.L systems that have only one big and one LITTLE cpu? Do these > > use SMP, too? > > Following definition of SMP says: > http://en.wikipedia.org/wiki/Symmetric_Multiprocessor > > A system is SMP when: > - It has same type of cores > - controlled by a single instance of OS. > > In big LITTLE first one is obviously not completely true as you pointed out. > But second one is and so I would say its an SMP system :) > > Don't know how it should be called though. MP maybe. > >> You can make it dependent on that if required. > > Well, it's not required. It's just that the corresponding question in > > make oldconfig isn't really an enrichment for a kernel targeting an > > Cortex M3 :-) > > Just to make it clear enough, you are saying it doesn't make any > sense to enable it for M3? But because it is disabled by default, > the problem is not seen? No I'm saying that asking me is bad because on an UP machine it won't matter what I answer. So please don't ask me if SMP is off. > Why? Can't we have two M3's on a SoC and run an SMP kernel over > it? Yeah, you can. Then you'd have SMP (or MP) enabled though and the choice for that workqueue thing makes a difference. In that case asking is OK. Best regards Uwe -- Pengutronix e.K. | Uwe Kleine-König | Industrial Linux Solutions | http://www.pengutronix.de/ | -- To unsubscribe from this list: send the line "unsubscribe linux-rt-users" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
