On Tue, May 18, 2021 at 03:39:27PM +0200, Vincent Guittot wrote: > On Mon, 17 May 2021 at 10:24, Beata Michalska <beata.michalska@xxxxxxx> wrote: > > > > Introducing new, complementary to SD_ASYM_CPUCAPACITY, sched_domain > > topology flag, to distinguish between shed_domains where any CPU > > capacity asymmetry is detected (SD_ASYM_CPUCAPACITY) and ones where > > a full range of CPU capacities is visible to all domain members > > (SD_ASYM_CPUCAPACITY_FULL). > > I'm not sure about what you want to detect: > > Is it a sched_domain level with a full range of cpu capacity, i.e. > with at least 1 min capacity and 1 max capacity ? > or do you want to get at least 1 cpu of each capacity ? That would be at least one CPU of each available capacity within given domain, so full -set- of available capacities within a domain. --- BR B. > > > > > > With the distinction between full and partial CPU capacity asymmetry, > > brought in by the newly introduced flag, the scope of the original > > SD_ASYM_CPUCAPACITY flag gets shifted, still maintaining the existing > > behaviour when one is detected on a given sched domain, allowing > > misfit migrations within sched domains that do not observe full range > > of CPU capacities but still do have members with different capacity > > values. It loses though it's meaning when it comes to the lowest CPU > > asymmetry sched_domain level per-cpu pointer, which is to be now > > denoted by SD_ASYM_CPUCAPACITY_FULL flag. > > > > Signed-off-by: Beata Michalska <beata.michalska@xxxxxxx> > > Reviewed-by: Valentin Schneider <valentin.schneider@xxxxxxx> > > --- > > include/linux/sched/sd_flags.h | 10 ++++++++++ > > 1 file changed, 10 insertions(+) > > > > diff --git a/include/linux/sched/sd_flags.h b/include/linux/sched/sd_flags.h > > index 34b21e9..57bde66 100644 > > --- a/include/linux/sched/sd_flags.h > > +++ b/include/linux/sched/sd_flags.h > > @@ -91,6 +91,16 @@ SD_FLAG(SD_WAKE_AFFINE, SDF_SHARED_CHILD) > > SD_FLAG(SD_ASYM_CPUCAPACITY, SDF_SHARED_PARENT | SDF_NEEDS_GROUPS) > > > > /* > > + * Domain members have different CPU capacities spanning all unique CPU > > + * capacity values. > > + * > > + * SHARED_PARENT: Set from the topmost domain down to the first domain where > > + * all available CPU capacities are visible > > + * NEEDS_GROUPS: Per-CPU capacity is asymmetric between groups. > > + */ > > +SD_FLAG(SD_ASYM_CPUCAPACITY_FULL, SDF_SHARED_PARENT | SDF_NEEDS_GROUPS) > > + > > +/* > > * Domain members share CPU capacity (i.e. SMT) > > * > > * SHARED_CHILD: Set from the base domain up until spanned CPUs no longer share > > -- > > 2.7.4 > >
