blob: cc921e6ba7091e845137978a01a8b764e1d20261 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
|
// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (c) 2017 Sagi Grimberg.
*/
#include <linux/blk-mq.h>
#include <linux/blk-mq-rdma.h>
#include <rdma/ib_verbs.h>
/**
* blk_mq_rdma_map_queues - provide a default queue mapping for rdma device
* @set: tagset to provide the mapping for
* @dev: rdma device associated with @set.
* @first_vec: first interrupt vectors to use for queues (usually 0)
*
* This function assumes the rdma device @dev has at least as many available
* interrupt vetors as @set has queues. It will then query it's affinity mask
* and built queue mapping that maps a queue to the CPUs that have irq affinity
* for the corresponding vector.
*
* In case either the driver passed a @dev with less vectors than
* @set->nr_hw_queues, or @dev does not provide an affinity mask for a
* vector, we fallback to the naive mapping.
*/
int blk_mq_rdma_map_queues(struct blk_mq_queue_map *map,
struct ib_device *dev, int first_vec)
{
const struct cpumask *mask;
unsigned int queue, cpu;
for (queue = 0; queue < map->nr_queues; queue++) {
mask = ib_get_vector_affinity(dev, first_vec + queue);
if (!mask)
goto fallback;
for_each_cpu(cpu, mask)
map->mq_map[cpu] = map->queue_offset + queue;
}
return 0;
fallback:
return blk_mq_map_queues(map);
}
EXPORT_SYMBOL_GPL(blk_mq_rdma_map_queues);
|
