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Date:   Mon, 1 Jul 2019 16:06:42 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     Patrick Bellasi <patrick.bellasi@arm.com>
Cc:     subhra mazumdar <subhra.mazumdar@oracle.com>,
        linux-kernel@vger.kernel.org, mingo@redhat.com, tglx@linutronix.de,
        steven.sistare@oracle.com, dhaval.giani@oracle.com,
        daniel.lezcano@linaro.org, vincent.guittot@linaro.org,
        viresh.kumar@linaro.org, tim.c.chen@linux.intel.com,
        mgorman@techsingularity.net, Paul Turner <pjt@google.com>,
        riel@surriel.com, morten.rasmussen@arm.com
Subject: Re: [RESEND PATCH v3 0/7] Improve scheduler scalability for fast path
Message-ID: <20190701140642.GX3402@hirez.programming.kicks-ass.net>
References: <20190627012919.4341-1-subhra.mazumdar@oracle.com>
 <20190701090204.GQ3402@hirez.programming.kicks-ass.net>
 <20190701135552.kb4os6bxxhh2lyw6@e110439-lin>
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On Mon, Jul 01, 2019 at 02:55:52PM +0100, Patrick Bellasi wrote:
> On 01-Jul 11:02, Peter Zijlstra wrote:

> > Hmmm?
> 
> Just one more requirement I think it's worth to consider since the
> beginning: CGroups support
> 
> That would be very welcome interface. Just because is so much more
> convenient (and safe) to set these bias on a group of tasks depending
> on their role in the system.
> 
> Do you have any idea on how we can expose such a "lantency-nice"
> property via CGroups? It's very similar to cpu.shares but it does not
> represent a resource which can be partitioned.

If the latency_nice idea lives; exactly like the normal nice? That is;
IIRC cgroupv2 has a nice value interface (see cpu_weight_nice_*()).

But yes, this isn't a resource per se; just a shared attribute like
thing.