lkml.org 
[lkml]   [2018]   [Jun]   [22]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    From
    SubjectRe: [PATCHv3 1/9] sched: Add static_key for asymmetric cpu capacity optimizations
    Hi Morten,

    On Wednesday 20 Jun 2018 at 10:05:41 (+0100), Morten Rasmussen wrote:
    > +static void update_asym_cpucapacity(int cpu)
    > +{
    > + int enable = false;
    > +
    > + rcu_read_lock();
    > + if (lowest_flag_domain(cpu, SD_ASYM_CPUCAPACITY))
    > + enable = true;
    > + rcu_read_unlock();
    > +
    > + if (enable) {
    > + /* This expects to be hotplug-safe */
    > + static_branch_enable_cpuslocked(&sched_asym_cpucapacity);
    > + }
    > +}

    What would happen if you hotplugged an entire cluster ? You'd loose the
    SD_ASYM_CPUCAPACITY flag but keep the static key is that right ? Should
    we care ?

    And also, Peter mentioned an issue with the EAS patches with multiple
    root_domains. Does that apply here as well ? What if you had a
    configuration with big and little CPUs in different root_domains for ex?

    Should we disable the static key in the above cases ?

    Thanks,
    Quentin

    \
     
     \ /
      Last update: 2018-06-22 10:22    [W:3.253 / U:0.124 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site