On Wed, Sep 23, 2015 at 09:54:08AM -0700, bseg...@google.com wrote: > > This second thought made a mistake (what was wrong with me). load_avg is > > for sure > > no greater than load with or without blocked load. > > > > With that said, it really does not matter what the following numbers are, > > 32bit or > > 64bit machine. What matters is that cfs_rq->load.weight is one that needs > > to worry > > whether overflow or not, not the load_avg. It is as simple as that. > > > > With that, I think we can and should get rid of the scale_load_down() > > for load_avg. > > load_avg yes is bounded by load.weight, but on 64-bit load_sum is only > bounded by load.weight * LOAD_AVG_MAX and is the same size as > load.weight (as I said below). There's still space for anything > reasonable though with 10 bits of SLR. You are absolutely right.
> >> > If NICE_0_LOAD is nice-0's load, and if SCHED_LOAD_SHIFT is to say how > >> > to get > >> > nice-0's load, I don't understand why you want to separate them. > >> > >> SCHED_LOAD_SHIFT is not how to get nice-0's load, it just happens to > >> have the same value as NICE_0_SHIFT. (I think anyway, SCHED_LOAD_* is > >> used in precisely one place other than the newish util_avg, and as I > >> mentioned it's not remotely clear what compute_imbalance is doing theer) > > > > Yes, it is not clear to me either. > > > > With the above proposal to get rid of scale_load_down() for load_avg, so I > > think > > now we can remove SCHED_LOAD_*, and rename scale_load() to > > user_to_kernel_load(), > > and raname scale_load_down() to kernel_to_user_load(). > > > > Hmm? > > I have no opinion on renaming the scale_load functions, it's certainly > reasonable, but the scale_load names seem fine too. Without scale_load_down() in load_avg, it seems they are only used when reading/writing load between user and kernel. I will ponder more, but lets see whether others have opinion. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
