Re: [PATCH] block, bfq: do the all counting of pending-request if CONFIG_BFQ_GROUP_IOSCHED is enabled

[Yuwei Guan <ssawgyw@gmail.com>]

On 2022/11/10 17:28, Yu Kuai wrote:
> Hi,
>
> 在 2022/11/09 21:29, Yuwei Guan 写道:
>> The 'bfqd->num_groups_with_pending_reqs' is used when
>> CONFIG_BFQ_GROUP_IOSCHED is enabled, so let the variables and processes
>> take effect when ONFIG_BFQ_GROUP_IOSCHED is enabled.
>>
>> Cc: Yu Kuai <yukuai3@huawei.com>
>> Signed-off-by: Yuwei Guan <Yuwei.Guan@zeekrlife.com>
>> ---
>>   block/bfq-iosched.c |  5 ++++-
>>   block/bfq-iosched.h |  6 ++++++
>>   block/bfq-wf2q.c    | 10 ++++++----
>>   3 files changed, 16 insertions(+), 5 deletions(-)
>>
>> diff --git a/block/bfq-iosched.c b/block/bfq-iosched.c
>> index 2381cf220ba2..5a648433fd89 100644
>> --- a/block/bfq-iosched.c
>> +++ b/block/bfq-iosched.c
>> @@ -6192,8 +6192,9 @@ static void bfq_completed_request(struct 
>> bfq_queue *bfqq, struct bfq_data *bfqd)
>>            * mechanism).
>>            */
>>           bfqq->budget_timeout = jiffies;
>> -
>> +#ifdef CONFIG_BFQ_GROUP_IOSCHED
>>           bfq_del_bfqq_in_groups_with_pending_reqs(bfqq);
>> +#endif
>>           bfq_weights_tree_remove(bfqq);
>>       }
>
> Thanks for the patch, this make sense. However, I prefer to
> declare a empty function if the config is disabled instead of adding
> "#ifdef" everywhere the function is called.

Thanks a lot for reviewing. Get it, I will send v1 soon.

>
> Thanks,
> Kuai
>>   @@ -7051,7 +7052,9 @@ static int bfq_init_queue(struct 
>> request_queue *q, struct elevator_type *e)
>>       bfqd->idle_slice_timer.function = bfq_idle_slice_timer;
>>         bfqd->queue_weights_tree = RB_ROOT_CACHED;
>> +#ifdef CONFIG_BFQ_GROUP_IOSCHED
>>       bfqd->num_groups_with_pending_reqs = 0;
>> +#endif
>>         INIT_LIST_HEAD(&bfqd->active_list);
>>       INIT_LIST_HEAD(&bfqd->idle_list);
>> diff --git a/block/bfq-iosched.h b/block/bfq-iosched.h
>> index 9fa89577322d..d6b9fad28a3b 100644
>> --- a/block/bfq-iosched.h
>> +++ b/block/bfq-iosched.h
>> @@ -197,8 +197,10 @@ struct bfq_entity {
>>       /* flag, set to request a weight, ioprio or ioprio_class 
>> change  */
>>       int prio_changed;
>>   +#ifdef CONFIG_BFQ_GROUP_IOSCHED
>>       /* flag, set if the entity is counted in 
>> groups_with_pending_reqs */
>>       bool in_groups_with_pending_reqs;
>> +#endif
>>         /* last child queue of entity created (for non-leaf entities) */
>>       struct bfq_queue *last_bfqq_created;
>> @@ -491,6 +493,7 @@ struct bfq_data {
>>        */
>>       struct rb_root_cached queue_weights_tree;
>>   +#ifdef CONFIG_BFQ_GROUP_IOSCHED
>>       /*
>>        * Number of groups with at least one process that
>>        * has at least one request waiting for completion. Note that
>> @@ -538,6 +541,7 @@ struct bfq_data {
>>        * with no request waiting for completion.
>>        */
>>       unsigned int num_groups_with_pending_reqs;
>> +#endif
>>         /*
>>        * Per-class (RT, BE, IDLE) number of bfq_queues containing
>> @@ -1074,8 +1078,10 @@ void bfq_requeue_bfqq(struct bfq_data *bfqd, 
>> struct bfq_queue *bfqq,
>>                 bool expiration);
>>   void bfq_del_bfqq_busy(struct bfq_queue *bfqq, bool expiration);
>>   void bfq_add_bfqq_busy(struct bfq_queue *bfqq);
>> +#ifdef CONFIG_BFQ_GROUP_IOSCHED
>>   void bfq_add_bfqq_in_groups_with_pending_reqs(struct bfq_queue *bfqq);
>>   void bfq_del_bfqq_in_groups_with_pending_reqs(struct bfq_queue *bfqq);
>> +#endif
>>     /* --------------- end of interface of B-WF2Q+ ---------------- */
>>   diff --git a/block/bfq-wf2q.c b/block/bfq-wf2q.c
>> index b02b53658ed4..a29187ecdc39 100644
>> --- a/block/bfq-wf2q.c
>> +++ b/block/bfq-wf2q.c
>> @@ -1610,16 +1610,15 @@ void bfq_requeue_bfqq(struct bfq_data *bfqd, 
>> struct bfq_queue *bfqq,
>>                       bfqq == bfqd->in_service_queue, expiration);
>>   }
>>   +#ifdef CONFIG_BFQ_GROUP_IOSCHED
>>   void bfq_add_bfqq_in_groups_with_pending_reqs(struct bfq_queue *bfqq)
>>   {
>>       struct bfq_entity *entity = &bfqq->entity;
>>         if (!entity->in_groups_with_pending_reqs) {
>>           entity->in_groups_with_pending_reqs = true;
>> -#ifdef CONFIG_BFQ_GROUP_IOSCHED
>>           if (!(bfqq_group(bfqq)->num_queues_with_pending_reqs++))
>>               bfqq->bfqd->num_groups_with_pending_reqs++;
>> -#endif
>>       }
>>   }
>>   @@ -1629,12 +1628,11 @@ void 
>> bfq_del_bfqq_in_groups_with_pending_reqs(struct bfq_queue *bfqq)
>>         if (entity->in_groups_with_pending_reqs) {
>>           entity->in_groups_with_pending_reqs = false;
>> -#ifdef CONFIG_BFQ_GROUP_IOSCHED
>>           if (!(--bfqq_group(bfqq)->num_queues_with_pending_reqs))
>>               bfqq->bfqd->num_groups_with_pending_reqs--;
>> -#endif
>>       }
>>   }
>> +#endif
>>     /*
>>    * Called when the bfqq no longer has requests pending, remove it from
>> @@ -1659,7 +1657,9 @@ void bfq_del_bfqq_busy(struct bfq_queue *bfqq, 
>> bool expiration)
>>       bfq_deactivate_bfqq(bfqd, bfqq, true, expiration);
>>         if (!bfqq->dispatched) {
>> +#ifdef CONFIG_BFQ_GROUP_IOSCHED
>>           bfq_del_bfqq_in_groups_with_pending_reqs(bfqq);
>> +#endif
>>           /*
>>            * Next function is invoked last, because it causes bfqq to be
>>            * freed. DO NOT use bfqq after the next function invocation.
>> @@ -1683,7 +1683,9 @@ void bfq_add_bfqq_busy(struct bfq_queue *bfqq)
>>       bfqd->busy_queues[bfqq->ioprio_class - 1]++;
>>         if (!bfqq->dispatched) {
>> +#ifdef CONFIG_BFQ_GROUP_IOSCHED
>>           bfq_add_bfqq_in_groups_with_pending_reqs(bfqq);
>> +#endif
>>           if (bfqq->wr_coeff == 1)
>>               bfq_weights_tree_add(bfqq);
>>       }
>>
>