| Message ID | 20211127101132.486806-9-yukuai3@huawei.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | support concurrent sync io for bfq on a specail occasion | expand |
> Il giorno 27 nov 2021, alle ore 11:11, Yu Kuai <yukuai3@huawei.com> ha scritto: > > Prepare to decrease 'num_groups_with_pending_reqs' earlier. > > Signed-off-by: Yu Kuai <yukuai3@huawei.com> > --- > block/bfq-iosched.c | 13 +++++-------- > 1 file changed, 5 insertions(+), 8 deletions(-) > > diff --git a/block/bfq-iosched.c b/block/bfq-iosched.c > index e3c31db4bffb..4239b3996e23 100644 > --- a/block/bfq-iosched.c > +++ b/block/bfq-iosched.c > @@ -882,6 +882,10 @@ void bfq_weights_tree_remove(struct bfq_data *bfqd, > { > struct bfq_entity *entity = bfqq->entity.parent; > > + bfqq->ref++; > + __bfq_weights_tree_remove(bfqd, bfqq, > + &bfqd->queue_weights_tree); > + > for_each_entity(entity) { > struct bfq_sched_data *sd = entity->my_sched_data; > > @@ -916,14 +920,7 @@ void bfq_weights_tree_remove(struct bfq_data *bfqd, > } > } > > - /* > - * Next function is invoked last, because it causes bfqq to be > - * freed if the following holds: bfqq is not in service and > - * has no dispatched request. DO NOT use bfqq after the next > - * function invocation. > - */ > - __bfq_weights_tree_remove(bfqd, bfqq, > - &bfqd->queue_weights_tree); > + bfq_put_queue(bfqq); > } > why it is not dangerous any longer to invoke __bfq_weights_tree_remove earlier, and the comment can be removed? Paolo > /* > -- > 2.31.1 >
在 2021/12/10 18:00, Paolo Valente 写道: > > >> Il giorno 27 nov 2021, alle ore 11:11, Yu Kuai <yukuai3@huawei.com> ha scritto: >> >> Prepare to decrease 'num_groups_with_pending_reqs' earlier. >> >> Signed-off-by: Yu Kuai <yukuai3@huawei.com> >> --- >> block/bfq-iosched.c | 13 +++++-------- >> 1 file changed, 5 insertions(+), 8 deletions(-) >> >> diff --git a/block/bfq-iosched.c b/block/bfq-iosched.c >> index e3c31db4bffb..4239b3996e23 100644 >> --- a/block/bfq-iosched.c >> +++ b/block/bfq-iosched.c >> @@ -882,6 +882,10 @@ void bfq_weights_tree_remove(struct bfq_data *bfqd, >> { >> struct bfq_entity *entity = bfqq->entity.parent; >> >> + bfqq->ref++; >> + __bfq_weights_tree_remove(bfqd, bfqq, >> + &bfqd->queue_weights_tree); >> + >> for_each_entity(entity) { >> struct bfq_sched_data *sd = entity->my_sched_data; >> >> @@ -916,14 +920,7 @@ void bfq_weights_tree_remove(struct bfq_data *bfqd, >> } >> } >> >> - /* >> - * Next function is invoked last, because it causes bfqq to be >> - * freed if the following holds: bfqq is not in service and >> - * has no dispatched request. DO NOT use bfqq after the next >> - * function invocation. >> - */ >> - __bfq_weights_tree_remove(bfqd, bfqq, >> - &bfqd->queue_weights_tree); >> + bfq_put_queue(bfqq); >> } >> > > why it is not dangerous any longer to invoke __bfq_weights_tree_remove earlier, and the comment can be removed? Hi, Paolo Here I grab an additional ref to the bfqq, thus the bfqq is ensured not to be free before bfq_put_queue() at the end of the function. Maybe some comments is more appropriate. Thanks, Kuai > > Paolo > >> /* >> -- >> 2.31.1 >> > > . >
diff --git a/block/bfq-iosched.c b/block/bfq-iosched.c index e3c31db4bffb..4239b3996e23 100644 --- a/block/bfq-iosched.c +++ b/block/bfq-iosched.c @@ -882,6 +882,10 @@ void bfq_weights_tree_remove(struct bfq_data *bfqd, { struct bfq_entity *entity = bfqq->entity.parent; + bfqq->ref++; + __bfq_weights_tree_remove(bfqd, bfqq, + &bfqd->queue_weights_tree); + for_each_entity(entity) { struct bfq_sched_data *sd = entity->my_sched_data; @@ -916,14 +920,7 @@ void bfq_weights_tree_remove(struct bfq_data *bfqd, } } - /* - * Next function is invoked last, because it causes bfqq to be - * freed if the following holds: bfqq is not in service and - * has no dispatched request. DO NOT use bfqq after the next - * function invocation. - */ - __bfq_weights_tree_remove(bfqd, bfqq, - &bfqd->queue_weights_tree); + bfq_put_queue(bfqq); } /*
Prepare to decrease 'num_groups_with_pending_reqs' earlier. Signed-off-by: Yu Kuai <yukuai3@huawei.com> --- block/bfq-iosched.c | 13 +++++-------- 1 file changed, 5 insertions(+), 8 deletions(-)