pagetypeinfo_showfree

static void pagetypeinfo_showfree_print(struct seq_file *m,
                    pg_data_t *pgdat, struct zone *zone)
{
    int order, mtype;
 
    for (mtype = 0; mtype < MIGRATE_TYPES; mtype++) {
        seq_printf(m, "Node %4d, zone %8s, type %12s ",
                    pgdat->node_id,
                    zone->name,
                    migratetype_names[mtype]);
        for (order = 0; order < MAX_ORDER; ++order) {
            unsigned long freecount = 0;
            struct free_area *area;
            struct list_head *curr;
            bool overflow = false;
 
            area = &(zone->free_area[order]);
 
            list_for_each(curr, &area->free_list[mtype]) {
                /*
                 * Cap the free_list iteration because it might
                 * be really large and we are under a spinlock
                 * so a long time spent here could trigger a
                 * hard lockup detector. Anyway this is a
                 * debugging tool so knowing there is a handful
                 * of pages of this order should be more than
                 * sufficient.
                 */
                if (++freecount >= 100000) {
                    overflow = true;
                    break;
                }
            }
            seq_printf(m, "%s%6lu ", overflow ? ">" : "", freecount);
            spin_unlock_irq(&zone->lock);
            cond_resched();
            spin_lock_irq(&zone->lock);
        }
        seq_putc(m, '\n');
    }
}
函数源码
