On 2023-01-20 at 20:24:30 -0800, Yury Norov wrote: > The function finds Nth set CPU in a given cpumask starting from a given > node. > > Leveraging the fact that each hop in sched_domains_numa_masks includes the > same or greater number of CPUs than the previous one, we can use binary > search on hops instead of linear walk, which makes the overall complexity > of O(log n) in terms of number of cpumask_weight() calls. > > Signed-off-by: Yury Norov <yury.norov@xxxxxxxxx> > Acked-by: Tariq Toukan <tariqt@xxxxxxxxxx> > Reviewed-by: Jacob Keller <jacob.e.keller@xxxxxxxxx> > Reviewed-by: Peter Lafreniere <peter@xxxxxxxx> > --- > include/linux/topology.h | 8 ++++++ > kernel/sched/topology.c | 57 ++++++++++++++++++++++++++++++++++++++++ > 2 files changed, 65 insertions(+) > [snip] > + * sched_numa_find_nth_cpu() - given the NUMA topology, find the Nth next cpu > + * closest to @cpu from @cpumask. Just minor question, the @cpu below is used as the index, right? What does "close to @cpu" mean above? > + * cpumask: cpumask to find a cpu from > + * cpu: Nth cpu to find Maybe also add description for @node? thanks, Chenyu
