57 lines · c
1// SPDX-License-Identifier: GPL-2.02/*3 * CPU <-> hardware queue mapping helpers4 *5 * Copyright (C) 2013-2014 Jens Axboe6 */7#include <linux/kernel.h>8#include <linux/threads.h>9#include <linux/module.h>10#include <linux/mm.h>11#include <linux/smp.h>12#include <linux/cpu.h>13#include <linux/group_cpus.h>14 15#include "blk.h"16#include "blk-mq.h"17 18void blk_mq_map_queues(struct blk_mq_queue_map *qmap)19{20 const struct cpumask *masks;21 unsigned int queue, cpu;22 23 masks = group_cpus_evenly(qmap->nr_queues);24 if (!masks) {25 for_each_possible_cpu(cpu)26 qmap->mq_map[cpu] = qmap->queue_offset;27 return;28 }29 30 for (queue = 0; queue < qmap->nr_queues; queue++) {31 for_each_cpu(cpu, &masks[queue])32 qmap->mq_map[cpu] = qmap->queue_offset + queue;33 }34 kfree(masks);35}36EXPORT_SYMBOL_GPL(blk_mq_map_queues);37 38/**39 * blk_mq_hw_queue_to_node - Look up the memory node for a hardware queue index40 * @qmap: CPU to hardware queue map.41 * @index: hardware queue index.42 *43 * We have no quick way of doing reverse lookups. This is only used at44 * queue init time, so runtime isn't important.45 */46int blk_mq_hw_queue_to_node(struct blk_mq_queue_map *qmap, unsigned int index)47{48 int i;49 50 for_each_possible_cpu(i) {51 if (index == qmap->mq_map[i])52 return cpu_to_node(i);53 }54 55 return NUMA_NO_NODE;56}57