lkml.org 
[lkml]   [2017]   [Apr]   [19]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    From
    SubjectRe: [patch V2 08/10] timer: Implement the hierarchical pull model
    On Tue, Apr 18, 2017 at 01:11:10PM +0200, Thomas Gleixner wrote:
    > +static struct tmigr_group *tmigr_get_group(unsigned int node, unsigned int lvl)
    > +{
    > + struct tmigr_group *group;
    > +
    > + /* Try to attach to an exisiting group first */
    > + list_for_each_entry(group, &tmigr_level_list[lvl], list) {
    > + /*
    > + * If @lvl is below the cross numa node level, check
    > + * whether this group belongs to the same numa node.
    > + */
    > + if (lvl < tmigr_crossnode_level && group->numa_node != node)
    > + continue;
    > + /* If the group has capacity, use it */
    > + if (group->num_childs < tmigr_childs_per_group) {
    > + group->num_childs++;
    > + return group;
    > + }

    This would result in SMT siblings not sharing groups on regular Intel
    systems, right? Since they get enumerated last.

    > + }
    > + /* Allocate and set up a new group */
    > + group = kzalloc_node(sizeof(*group), GFP_KERNEL, node);
    > + if (!group)
    > + return ERR_PTR(-ENOMEM);
    > +
    > + if (!zalloc_cpumask_var_node(&group->cpus, GFP_KERNEL, node)) {
    > + kfree(group);
    > + return ERR_PTR(-ENOMEM);
    > + }

    So if you place that cpumask last, you can do:

    group = kzalloc_node(sizeof(*group) + cpumask_size(),
    GFP_KERNEL, node);

    > + tmigr_init_group(group, lvl, node);
    > + /* Setup successful. Add it to the hierarchy */
    > + list_add(&group->list, &tmigr_level_list[lvl]);
    > + return group;
    > +}

    \
     
     \ /
      Last update: 2017-04-19 10:11    [W:4.275 / U:0.020 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site