Re: [PATCH 5/6] sched/fair: Consider the idle state of the whole core for load balance

[Tim Chen]

On Fri, 2023-05-05 at 15:23 +0200, Peter Zijlstra wrote:
> On Thu, May 04, 2023 at 09:09:55AM -0700, Tim Chen wrote:
> 
> > @@ -10709,11 +10709,26 @@ static int should_we_balance(struct lb_env *env)
> >  	for_each_cpu_and(cpu, group_balance_mask(sg), env->cpus) {
> >  		if (!idle_cpu(cpu))
> >  			continue;
> > +		else {
> > +			/*
> > +			 * Don't balance to idle SMT in busy core right away when
> > +			 * balancing cores, but remember the first idle SMT CPU for
> > +			 * later consideration.  Find CPU on an idle core first.
> > +			 */
> > +			if (!(env->sd->flags & SD_SHARE_CPUCAPACITY) && !is_core_idle(cpu)) {
> > +				if (idle_smt == -1)
> > +					idle_smt = cpu;
> > +				continue;
> > +			}
> > +		}
> 
> Not only does that bust CodingStyle, it's also entirely daft. What
> exactly is the purpose of that else statement?
> 
> 

Yeah, that's a dumb "else" statement.  Will remove that.

Tim