mirror of https://lore.kernel.org/lkml/
 help / color / mirror / Atom feed
From: Dietmar Eggemann <dietmar.eggemann@arm.com>
To: Peter Zijlstra <peterz@infradead.org>,
	Rohit Jain <rohit.k.jain@oracle.com>
Cc: mingo@redhat.com, linux-kernel@vger.kernel.org,
	steven.sistare@oracle.com, dhaval.giani@oracle.com,
	joelaf@google.com, vincent.guittot@linaro.org,
	morten.rasmussen@arm.com, eas-dev@lists.linaro.org
Subject: Re: [RESEND PATCH] sched/fair: consider RT/IRQ pressure in select_idle_sibling
Date: Fri, 9 Feb 2018 16:46:53 +0100	[thread overview]
Message-ID: <2b3a903f-fbb6-cc0e-8a5d-e3329e1276c7@arm.com> (raw)
In-Reply-To: <20180209125358.GO25201@hirez.programming.kicks-ass.net>

On 02/09/2018 01:53 PM, Peter Zijlstra wrote:
> On Mon, Jan 29, 2018 at 03:27:09PM -0800, Rohit Jain wrote:

[...]

>> @@ -6173,8 +6183,15 @@ static int select_idle_cpu(struct task_struct *p, struct sched_domain *sd, int t
>>   			return -1;
>>   		if (!cpumask_test_cpu(cpu, &p->cpus_allowed))
>>   			continue;
>> +		if (idle_cpu(cpu)) {
>> +			if (full_capacity(cpu)) {
>> +				best_cpu = cpu;
>> +				break;
>> +			} else if (capacity_of(cpu) > best_cap) {
>> +				best_cap = capacity_of(cpu);
>> +				best_cpu = cpu;
>> +			}
>> +		}
> 
> No need for the else. And you'll note you're once again inconsistent
> with your previous self.
> 
> But here I worry about big.little a wee bit. I think we're allowed big
> and little cores on the same L3 these days, and you can't directly
> compare capacity between them.
> 
> Morten / Dietmar, any comments?

Yes, for DynamIQ (big.little successor) systems, those cpus can have 
different capacity_orig_of() values already.

  reply	other threads:[~2018-02-09 15:46 UTC|newest]

Thread overview: 18+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-01-29 23:27 Rohit Jain
2018-01-30  3:39 ` Joel Fernandes
2018-01-30 19:47   ` Rohit Jain
2018-01-31  1:57     ` Joel Fernandes
2018-01-31 17:50       ` Rohit Jain
2018-02-06  6:50         ` Joel Fernandes
2018-02-06  6:51           ` Joel Fernandes
2018-02-06 17:41           ` Rohit Jain
2018-02-09 12:37           ` Peter Zijlstra
2018-02-06  6:42     ` Joel Fernandes
2018-02-06 17:36       ` Rohit Jain
2018-02-09 12:35   ` Peter Zijlstra
2018-02-09 12:53 ` Peter Zijlstra
2018-02-09 15:46   ` Dietmar Eggemann [this message]
2018-02-09 22:05     ` Rohit Jain
2018-02-14  9:11       ` Dietmar Eggemann
2018-02-09 22:17   ` Rohit Jain
2018-03-10 20:41   ` Rohit Jain

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=2b3a903f-fbb6-cc0e-8a5d-e3329e1276c7@arm.com \
    --to=dietmar.eggemann@arm.com \
    --cc=dhaval.giani@oracle.com \
    --cc=eas-dev@lists.linaro.org \
    --cc=joelaf@google.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mingo@redhat.com \
    --cc=morten.rasmussen@arm.com \
    --cc=peterz@infradead.org \
    --cc=rohit.k.jain@oracle.com \
    --cc=steven.sistare@oracle.com \
    --cc=vincent.guittot@linaro.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox

all inboxes | Powered by JetHome®