linux-kernel - Re: [PATCH] sched: Call update_group_power only for local

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Thu, 08 Jul 2010 10:50:16 -0700
From:	Suresh Siddha <suresh.b.siddha@...el.com>
To:	Peter Zijlstra <peterz@...radead.org>
Cc:	Venkatesh Pallipadi <venki@...gle.com>,
	LKML <linux-kernel@...r.kernel.org>,
	Gautham R Shenoy <ego@...ibm.com>,
	Joel Schopp <jschopp@...tin.ibm.com>,
	Michael Neuling <mikey@...ling.org>
Subject: Re: [PATCH] sched: Call update_group_power only for local_group

On Thu, 2010-07-08 at 10:49 -0700, Peter Zijlstra wrote:
> On Thu, 2010-07-08 at 10:45 -0700, Suresh Siddha wrote:
> >  
> > @@ -2456,6 +2454,9 @@ static inline void update_sd_lb_stats(struct sched_domain *sd, int this_cpu,
> >  	init_sd_power_savings_stats(sd, sds, idle);
> >  	load_idx = get_sd_load_idx(sd, idle);
> >  
> > +	if (this_cpu == smp_processor_id())
> > +		update_group_power(sd, this_cpu);
> > +
> >  	do {
> >  		int local_group;
> 
> Which will break for nohz_idle_balance..

Then the logic is broken somewhere because update_group_power() reads
APERF/MPERF MSR's which doesn't make sense when this_cpu !=
smp_processor_id(). What am I missing?

thanks,
suresh

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/