1 // SPDX-License-Identifier: GPL-2.0 <<
2 /* 1 /*
3 * CPU <-> hardware queue mapping helpers 2 * CPU <-> hardware queue mapping helpers
4 * 3 *
5 * Copyright (C) 2013-2014 Jens Axboe 4 * Copyright (C) 2013-2014 Jens Axboe
6 */ 5 */
7 #include <linux/kernel.h> 6 #include <linux/kernel.h>
8 #include <linux/threads.h> 7 #include <linux/threads.h>
9 #include <linux/module.h> 8 #include <linux/module.h>
10 #include <linux/mm.h> 9 #include <linux/mm.h>
11 #include <linux/smp.h> 10 #include <linux/smp.h>
12 #include <linux/cpu.h> 11 #include <linux/cpu.h>
13 #include <linux/group_cpus.h> <<
14 12
>> 13 #include <linux/blk-mq.h>
15 #include "blk.h" 14 #include "blk.h"
16 #include "blk-mq.h" 15 #include "blk-mq.h"
17 16
18 void blk_mq_map_queues(struct blk_mq_queue_map !! 17 static int cpu_to_queue_index(struct blk_mq_queue_map *qmap,
>> 18 unsigned int nr_queues, const int cpu)
19 { 19 {
20 const struct cpumask *masks; !! 20 return qmap->queue_offset + (cpu % nr_queues);
21 unsigned int queue, cpu; !! 21 }
22 22
23 masks = group_cpus_evenly(qmap->nr_que !! 23 static int get_first_sibling(unsigned int cpu)
24 if (!masks) { !! 24 {
25 for_each_possible_cpu(cpu) !! 25 unsigned int ret;
26 qmap->mq_map[cpu] = qm !! 26
27 return; !! 27 ret = cpumask_first(topology_sibling_cpumask(cpu));
28 } !! 28 if (ret < nr_cpu_ids)
>> 29 return ret;
>> 30
>> 31 return cpu;
>> 32 }
29 33
30 for (queue = 0; queue < qmap->nr_queue !! 34 int blk_mq_map_queues(struct blk_mq_queue_map *qmap)
31 for_each_cpu(cpu, &masks[queue !! 35 {
32 qmap->mq_map[cpu] = qm !! 36 unsigned int *map = qmap->mq_map;
>> 37 unsigned int nr_queues = qmap->nr_queues;
>> 38 unsigned int cpu, first_sibling;
>> 39
>> 40 for_each_possible_cpu(cpu) {
>> 41 /*
>> 42 * First do sequential mapping between CPUs and queues.
>> 43 * In case we still have CPUs to map, and we have some number of
>> 44 * threads per cores then map sibling threads to the same queue for
>> 45 * performace optimizations.
>> 46 */
>> 47 if (cpu < nr_queues) {
>> 48 map[cpu] = cpu_to_queue_index(qmap, nr_queues, cpu);
>> 49 } else {
>> 50 first_sibling = get_first_sibling(cpu);
>> 51 if (first_sibling == cpu)
>> 52 map[cpu] = cpu_to_queue_index(qmap, nr_queues, cpu);
>> 53 else
>> 54 map[cpu] = map[first_sibling];
>> 55 }
33 } 56 }
34 kfree(masks); !! 57
>> 58 return 0;
35 } 59 }
36 EXPORT_SYMBOL_GPL(blk_mq_map_queues); 60 EXPORT_SYMBOL_GPL(blk_mq_map_queues);
37 61
38 /** !! 62 /*
39 * blk_mq_hw_queue_to_node - Look up the memor <<
40 * @qmap: CPU to hardware queue map. <<
41 * @index: hardware queue index. <<
42 * <<
43 * We have no quick way of doing reverse looku 63 * We have no quick way of doing reverse lookups. This is only used at
44 * queue init time, so runtime isn't important 64 * queue init time, so runtime isn't important.
45 */ 65 */
46 int blk_mq_hw_queue_to_node(struct blk_mq_queu 66 int blk_mq_hw_queue_to_node(struct blk_mq_queue_map *qmap, unsigned int index)
47 { 67 {
48 int i; 68 int i;
49 69
50 for_each_possible_cpu(i) { 70 for_each_possible_cpu(i) {
51 if (index == qmap->mq_map[i]) 71 if (index == qmap->mq_map[i])
52 return cpu_to_node(i); !! 72 return local_memory_node(cpu_to_node(i));
53 } 73 }
54 74
55 return NUMA_NO_NODE; 75 return NUMA_NO_NODE;
56 } 76 }
57 77
Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.