On 10/29/18 12:15 PM, Bart Van Assche wrote:
> On Mon, 2018-10-29 at 10:37 -0600, Jens Axboe wrote:
>> -static inline struct blk_mq_hw_ctx *blk_mq_map_queue(struct request_queue *q,
>> - unsigned int flags,
>> - int cpu)
>> +static inline struct blk_mq_hw_ctx *blk_mq_map_queue_type(struct request_queue *q,
>> + int type, int cpu)
>> {
>> struct blk_mq_tag_set *set = q->tag_set;
>>
>> - return q->queue_hw_ctx[set->map[0].mq_map[cpu]];
>> + return q->queue_hw_ctx[set->map[type].mq_map[cpu]];
>> }
>>
>> -static inline struct blk_mq_hw_ctx *blk_mq_map_queue_type(struct request_queue *q,
>> - int type, int cpu)
>> +static inline struct blk_mq_hw_ctx *blk_mq_map_queue(struct request_queue *q,
>> + unsigned int flags,
>> + int cpu)
>> {
>> - return blk_mq_map_queue(q, type, cpu);
>> + int type = 0;
>> +
>> + if (q->mq_ops->flags_to_type)
>> + type = q->mq_ops->flags_to_type(q, flags);
>> +
>> + return blk_mq_map_queue_type(q, type, cpu);
>> }
>
> How about adding a comment above both these functions that explains their
> purpose? Since blk_mq_map_queue() maps rq->cmd_flags and the cpu index to
> a hardware context, how about renaming blk_mq_map_queue() into
> blk_mq_map_cmd_flags()?
I don't want to rename it, but I've added a kerneldoc function header to
both of them.
>> diff --git a/include/linux/blk-mq.h b/include/linux/blk-mq.h
>> index f9e19962a22f..837087cf07cc 100644
>> --- a/include/linux/blk-mq.h
>> +++ b/include/linux/blk-mq.h
>> @@ -86,6 +86,7 @@ enum {
>>
>> struct blk_mq_tag_set {
>> struct blk_mq_queue_map map[HCTX_MAX_TYPES];
>> + unsigned int nr_maps;
>> const struct blk_mq_ops *ops;
>> unsigned int nr_hw_queues;
>> unsigned int queue_depth; /* max hw supported */
>> @@ -109,6 +110,7 @@ struct blk_mq_queue_data {
>>
>> typedef blk_status_t (queue_rq_fn)(struct blk_mq_hw_ctx *,
>> const struct blk_mq_queue_data *);
>> +typedef int (flags_to_type_fn)(struct request_queue *, unsigned int);
>
> How about adding a comment that the format of the second argument of
> flags_to_type_fn is the same as that of rq->cmd_flags?
Done
--
Jens Axboe
