| Message ID | 20210806020826.1407257-2-yukuai3@huawei.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | optimize the bfq queue idle judgment | expand |
> Il giorno 6 ago 2021, alle ore 04:08, Yu Kuai <yukuai3@huawei.com> ha scritto: > > Add a new member in bfq_data to track number of queues that are in > root_group with any pending requests. maybe modify the last part of the sentence as: ... and that have some pending request > This will be used in next patch > to optmize queue idle judgment when root_group doesn't have any > pending requests. > > Signed-off-by: Yu Kuai <yukuai3@huawei.com> > --- > block/bfq-iosched.c | 8 +++++++- > block/bfq-iosched.h | 13 +++++++++++-- > block/bfq-wf2q.c | 37 ++++++++++++++++++++++++------------- > 3 files changed, 42 insertions(+), 16 deletions(-) > > diff --git a/block/bfq-iosched.c b/block/bfq-iosched.c > index 727955918563..7c6b412f9a9c 100644 > --- a/block/bfq-iosched.c > +++ b/block/bfq-iosched.c > @@ -859,8 +859,14 @@ void __bfq_weights_tree_remove(struct bfq_data *bfqd, > void bfq_weights_tree_remove(struct bfq_data *bfqd, > struct bfq_queue *bfqq) > { > - struct bfq_entity *entity = bfqq->entity.parent; > + struct bfq_entity *entity = &bfqq->entity; > + > + if (entity->in_groups_with_pending_reqs) { > + entity->in_groups_with_pending_reqs = false; > + bfqd->num_queues_with_pending_reqs_in_root--; Here you cross the comment "The decrement of num_groups_with_pending_reqs is not performed immediately upon ...". Find a way to - move that comment up, and to make it correct for this slightly different decrement - leave a correct comment (probably shorter) in the original position > + } > > + entity = entity->parent; > for_each_entity(entity) { > struct bfq_sched_data *sd = entity->my_sched_data; > > diff --git a/block/bfq-iosched.h b/block/bfq-iosched.h > index 99c2a3cb081e..610769214f72 100644 > --- a/block/bfq-iosched.h > +++ b/block/bfq-iosched.h > @@ -195,7 +195,12 @@ struct bfq_entity { > /* flag, set to request a weight, ioprio or ioprio_class change */ > int prio_changed; > > - /* flag, set if the entity is counted in groups_with_pending_reqs */ > + /* > + * If entity represents bfq_group, this flag will set will be set? > if the group is > + * not root_group and have has > any pending requests; If entity represents one more nit: use lowercase after semicolon > + * bfq_queue, this flag will set will be set > if the queue is in root_group and have > + * any pending requests. > + */ > bool in_groups_with_pending_reqs; > The name of the above field follows from the fact that entity is counted in groups_with_pending_reqs. You change this fact, because, in your patch, a queue is not counted in groups_with_pending_reqs. But you leave the same name. This creates confusion. > /* last child queue of entity created (for non-leaf entities) */ > @@ -539,7 +544,11 @@ struct bfq_data { > * with no request waiting for completion. > */ > unsigned int num_groups_with_pending_reqs; > - > + /* > + * number of queues that are in root_group with at least one request > + * waiting for completion. please link somehow this comment to the long comment that comes before it > + */ > + unsigned int num_queues_with_pending_reqs_in_root; Why using two counters? I mean, couldn't you simply count also the root group in num_groups_with_pending_reqs? > /* > * Per-class (RT, BE, IDLE) number of bfq_queues containing > * requests (including the queue in service, even if it is > diff --git a/block/bfq-wf2q.c b/block/bfq-wf2q.c > index 7a462df71f68..188c8f907219 100644 > --- a/block/bfq-wf2q.c > +++ b/block/bfq-wf2q.c > @@ -946,6 +946,29 @@ static void bfq_update_fin_time_enqueue(struct bfq_entity *entity, > bfq_active_insert(st, entity); > } > > +static void bfq_update_groups_with_pending_reqs(struct bfq_entity *entity) > +{ > +#ifdef CONFIG_BFQ_GROUP_IOSCHED > + struct bfq_queue *bfqq = bfq_entity_to_bfqq(entity); > + why do you introduce an extra variable bfqq, instead of doing as in the original version of the code? In addition, you remove the comment /* bfq_group */ Thanks, Paolo > + if (bfqq) { > + if (!entity->parent && !entity->in_groups_with_pending_reqs) { > + entity->in_groups_with_pending_reqs = true; > + bfqq->bfqd->num_queues_with_pending_reqs_in_root++; > + } > + } else { > + if (!entity->in_groups_with_pending_reqs) { > + struct bfq_group *bfqg = > + container_of(entity, struct bfq_group, entity); > + struct bfq_data *bfqd = bfqg->bfqd; > + > + entity->in_groups_with_pending_reqs = true; > + bfqd->num_groups_with_pending_reqs++; > + } > + } > +#endif > +} > + > /** > * __bfq_activate_entity - handle activation of entity. > * @entity: the entity being activated. > @@ -999,19 +1022,7 @@ static void __bfq_activate_entity(struct bfq_entity *entity, > entity->on_st_or_in_serv = true; > } > > -#ifdef CONFIG_BFQ_GROUP_IOSCHED > - if (!bfq_entity_to_bfqq(entity)) { /* bfq_group */ > - struct bfq_group *bfqg = > - container_of(entity, struct bfq_group, entity); > - struct bfq_data *bfqd = bfqg->bfqd; > - > - if (!entity->in_groups_with_pending_reqs) { > - entity->in_groups_with_pending_reqs = true; > - bfqd->num_groups_with_pending_reqs++; > - } > - } > -#endif > - > + bfq_update_groups_with_pending_reqs(entity); > bfq_update_fin_time_enqueue(entity, st, backshifted); > } > > -- > 2.31.1 >
On 2021/08/27 1:00, Paolo Valente wrote: > > >> Il giorno 6 ago 2021, alle ore 04:08, Yu Kuai <yukuai3@huawei.com> ha scritto: >> >> Add a new member in bfq_data to track number of queues that are in >> root_group with any pending requests. > > maybe modify the last part of the sentence as: ... and that have some pending request > >> This will be used in next patch >> to optmize queue idle judgment when root_group doesn't have any >> pending requests. >> >> Signed-off-by: Yu Kuai <yukuai3@huawei.com> >> --- >> block/bfq-iosched.c | 8 +++++++- >> block/bfq-iosched.h | 13 +++++++++++-- >> block/bfq-wf2q.c | 37 ++++++++++++++++++++++++------------- >> 3 files changed, 42 insertions(+), 16 deletions(-) >> >> diff --git a/block/bfq-iosched.c b/block/bfq-iosched.c >> index 727955918563..7c6b412f9a9c 100644 >> --- a/block/bfq-iosched.c >> +++ b/block/bfq-iosched.c >> @@ -859,8 +859,14 @@ void __bfq_weights_tree_remove(struct bfq_data *bfqd, >> void bfq_weights_tree_remove(struct bfq_data *bfqd, >> struct bfq_queue *bfqq) >> { >> - struct bfq_entity *entity = bfqq->entity.parent; >> + struct bfq_entity *entity = &bfqq->entity; >> + >> + if (entity->in_groups_with_pending_reqs) { >> + entity->in_groups_with_pending_reqs = false; >> + bfqd->num_queues_with_pending_reqs_in_root--; > > Here you cross the comment "The decrement of > num_groups_with_pending_reqs is not performed immediately upon ...". > > Find a way to > - move that comment up, and to make it correct for this slightly > different decrement > - leave a correct comment (probably shorter) in the original position > >> + } >> >> + entity = entity->parent; >> for_each_entity(entity) { >> struct bfq_sched_data *sd = entity->my_sched_data; >> >> diff --git a/block/bfq-iosched.h b/block/bfq-iosched.h >> index 99c2a3cb081e..610769214f72 100644 >> --- a/block/bfq-iosched.h >> +++ b/block/bfq-iosched.h >> @@ -195,7 +195,12 @@ struct bfq_entity { >> /* flag, set to request a weight, ioprio or ioprio_class change */ >> int prio_changed; >> >> - /* flag, set if the entity is counted in groups_with_pending_reqs */ >> + /* >> + * If entity represents bfq_group, this flag will set > > will be set? > >> if the group is >> + * not root_group and have > > has > >> any pending requests; If entity represents > > one more nit: use lowercase after semicolon > >> + * bfq_queue, this flag will set > > will be set > >> if the queue is in root_group and have >> + * any pending requests. >> + */ >> bool in_groups_with_pending_reqs; >> > > The name of the above field follows from the fact that entity is > counted in groups_with_pending_reqs. You change this fact, because, > in your patch, a queue is not counted in groups_with_pending_reqs. > But you leave the same name. This creates confusion. > > >> /* last child queue of entity created (for non-leaf entities) */ >> @@ -539,7 +544,11 @@ struct bfq_data { >> * with no request waiting for completion. >> */ >> unsigned int num_groups_with_pending_reqs; >> - >> + /* >> + * number of queues that are in root_group with at least one request >> + * waiting for completion. > > please link somehow this comment to the long comment that comes before it > >> + */ >> + unsigned int num_queues_with_pending_reqs_in_root; > > Why using two counters? I mean, couldn't you simply count also the > root group in num_groups_with_pending_reqs? Hi, Paolo Thanks for taking time reviewing these patches I was doing this too complicated, while counting root group into num_groups_with_pending_reqs is much easier. I'll do this in next iteration. Thanks Yu Kuai > >> /* >> * Per-class (RT, BE, IDLE) number of bfq_queues containing >> * requests (including the queue in service, even if it is >> diff --git a/block/bfq-wf2q.c b/block/bfq-wf2q.c >> index 7a462df71f68..188c8f907219 100644 >> --- a/block/bfq-wf2q.c >> +++ b/block/bfq-wf2q.c >> @@ -946,6 +946,29 @@ static void bfq_update_fin_time_enqueue(struct bfq_entity *entity, >> bfq_active_insert(st, entity); >> } >> >> +static void bfq_update_groups_with_pending_reqs(struct bfq_entity *entity) >> +{ >> +#ifdef CONFIG_BFQ_GROUP_IOSCHED >> + struct bfq_queue *bfqq = bfq_entity_to_bfqq(entity); >> + > > why do you introduce an extra variable bfqq, instead of doing as in > the original version of the code? In addition, you remove the comment > /* bfq_group */ > > Thanks, > Paolo > >> + if (bfqq) { >> + if (!entity->parent && !entity->in_groups_with_pending_reqs) { >> + entity->in_groups_with_pending_reqs = true; >> + bfqq->bfqd->num_queues_with_pending_reqs_in_root++; >> + } >> + } else { >> + if (!entity->in_groups_with_pending_reqs) { >> + struct bfq_group *bfqg = >> + container_of(entity, struct bfq_group, entity); >> + struct bfq_data *bfqd = bfqg->bfqd; >> + >> + entity->in_groups_with_pending_reqs = true; >> + bfqd->num_groups_with_pending_reqs++; >> + } >> + } >> +#endif >> +} >> + >> /** >> * __bfq_activate_entity - handle activation of entity. >> * @entity: the entity being activated. >> @@ -999,19 +1022,7 @@ static void __bfq_activate_entity(struct bfq_entity *entity, >> entity->on_st_or_in_serv = true; >> } >> >> -#ifdef CONFIG_BFQ_GROUP_IOSCHED >> - if (!bfq_entity_to_bfqq(entity)) { /* bfq_group */ >> - struct bfq_group *bfqg = >> - container_of(entity, struct bfq_group, entity); >> - struct bfq_data *bfqd = bfqg->bfqd; >> - >> - if (!entity->in_groups_with_pending_reqs) { >> - entity->in_groups_with_pending_reqs = true; >> - bfqd->num_groups_with_pending_reqs++; >> - } >> - } >> -#endif >> - >> + bfq_update_groups_with_pending_reqs(entity); >> bfq_update_fin_time_enqueue(entity, st, backshifted); >> } >> >> -- >> 2.31.1 >> > > . >
diff --git a/block/bfq-iosched.c b/block/bfq-iosched.c index 727955918563..7c6b412f9a9c 100644 --- a/block/bfq-iosched.c +++ b/block/bfq-iosched.c @@ -859,8 +859,14 @@ void __bfq_weights_tree_remove(struct bfq_data *bfqd, void bfq_weights_tree_remove(struct bfq_data *bfqd, struct bfq_queue *bfqq) { - struct bfq_entity *entity = bfqq->entity.parent; + struct bfq_entity *entity = &bfqq->entity; + + if (entity->in_groups_with_pending_reqs) { + entity->in_groups_with_pending_reqs = false; + bfqd->num_queues_with_pending_reqs_in_root--; + } + entity = entity->parent; for_each_entity(entity) { struct bfq_sched_data *sd = entity->my_sched_data; diff --git a/block/bfq-iosched.h b/block/bfq-iosched.h index 99c2a3cb081e..610769214f72 100644 --- a/block/bfq-iosched.h +++ b/block/bfq-iosched.h @@ -195,7 +195,12 @@ struct bfq_entity { /* flag, set to request a weight, ioprio or ioprio_class change */ int prio_changed; - /* flag, set if the entity is counted in groups_with_pending_reqs */ + /* + * If entity represents bfq_group, this flag will set if the group is + * not root_group and have any pending requests; If entity represents + * bfq_queue, this flag will set if the queue is in root_group and have + * any pending requests. + */ bool in_groups_with_pending_reqs; /* last child queue of entity created (for non-leaf entities) */ @@ -539,7 +544,11 @@ struct bfq_data { * with no request waiting for completion. */ unsigned int num_groups_with_pending_reqs; - + /* + * number of queues that are in root_group with at least one request + * waiting for completion. + */ + unsigned int num_queues_with_pending_reqs_in_root; /* * Per-class (RT, BE, IDLE) number of bfq_queues containing * requests (including the queue in service, even if it is diff --git a/block/bfq-wf2q.c b/block/bfq-wf2q.c index 7a462df71f68..188c8f907219 100644 --- a/block/bfq-wf2q.c +++ b/block/bfq-wf2q.c @@ -946,6 +946,29 @@ static void bfq_update_fin_time_enqueue(struct bfq_entity *entity, bfq_active_insert(st, entity); } +static void bfq_update_groups_with_pending_reqs(struct bfq_entity *entity) +{ +#ifdef CONFIG_BFQ_GROUP_IOSCHED + struct bfq_queue *bfqq = bfq_entity_to_bfqq(entity); + + if (bfqq) { + if (!entity->parent && !entity->in_groups_with_pending_reqs) { + entity->in_groups_with_pending_reqs = true; + bfqq->bfqd->num_queues_with_pending_reqs_in_root++; + } + } else { + if (!entity->in_groups_with_pending_reqs) { + struct bfq_group *bfqg = + container_of(entity, struct bfq_group, entity); + struct bfq_data *bfqd = bfqg->bfqd; + + entity->in_groups_with_pending_reqs = true; + bfqd->num_groups_with_pending_reqs++; + } + } +#endif +} + /** * __bfq_activate_entity - handle activation of entity. * @entity: the entity being activated. @@ -999,19 +1022,7 @@ static void __bfq_activate_entity(struct bfq_entity *entity, entity->on_st_or_in_serv = true; } -#ifdef CONFIG_BFQ_GROUP_IOSCHED - if (!bfq_entity_to_bfqq(entity)) { /* bfq_group */ - struct bfq_group *bfqg = - container_of(entity, struct bfq_group, entity); - struct bfq_data *bfqd = bfqg->bfqd; - - if (!entity->in_groups_with_pending_reqs) { - entity->in_groups_with_pending_reqs = true; - bfqd->num_groups_with_pending_reqs++; - } - } -#endif - + bfq_update_groups_with_pending_reqs(entity); bfq_update_fin_time_enqueue(entity, st, backshifted); }
Add a new member in bfq_data to track number of queues that are in root_group with any pending requests. This will be used in next patch to optmize queue idle judgment when root_group doesn't have any pending requests. Signed-off-by: Yu Kuai <yukuai3@huawei.com> --- block/bfq-iosched.c | 8 +++++++- block/bfq-iosched.h | 13 +++++++++++-- block/bfq-wf2q.c | 37 ++++++++++++++++++++++++------------- 3 files changed, 42 insertions(+), 16 deletions(-)