On Sun, Oct 22, 2017 at 01:47:54PM +0000, Israel Rukshin wrote: > Currently, blk_mq_tagset_iter() iterate over initial hctx tags only. > In case scheduler is used, it doesn't iterate the hctx scheduler tags > and the static request aren't been updated. > For example, while using NVMe over Fabrics RDMA host, this cause us not to > reinit the scheduler requests and thus not re-register all the memory regions > during the tagset re-initialization in the reconnect flow. > > This may lead to a memory registration error: > "MEMREG for CQE 0xffff88044c14dce8 failed with status memory > management operation error (6)" > > Signed-off-by: Israel Rukshin <[email protected]> > Reviewed-by: Max Gurtovoy <[email protected]> > --- > > The commit is based on nvme branch for 4.15 which includes > Sagi's patches for reinit_tagset. > > --- > block/blk-mq-sched.c | 3 +++ > block/blk-mq-tag.c | 16 ++++++++++++++++ > block/blk-mq.c | 14 +++++++++++++- > include/linux/blk-mq.h | 1 + > 4 files changed, 33 insertions(+), 1 deletion(-) > > diff --git a/block/blk-mq-sched.c b/block/blk-mq-sched.c > index 4ab6943..4db9797 100644 > --- a/block/blk-mq-sched.c > +++ b/block/blk-mq-sched.c > @@ -426,6 +426,7 @@ static void blk_mq_sched_free_tags(struct blk_mq_tag_set > *set, > blk_mq_free_rqs(set, hctx->sched_tags, hctx_idx); > blk_mq_free_rq_map(hctx->sched_tags); > hctx->sched_tags = NULL; > + set->sched_tags[hctx_idx] = NULL; > } > } > > @@ -441,6 +442,8 @@ static int blk_mq_sched_alloc_tags(struct request_queue > *q, > if (!hctx->sched_tags) > return -ENOMEM; > > + set->sched_tags[hctx_idx] = hctx->sched_tags; > + > ret = blk_mq_alloc_rqs(set, hctx->sched_tags, hctx_idx, q->nr_requests); > if (ret) > blk_mq_sched_free_tags(set, hctx, hctx_idx); > diff --git a/block/blk-mq-tag.c b/block/blk-mq-tag.c > index c81b40e..c290de0 100644 > --- a/block/blk-mq-tag.c > +++ b/block/blk-mq-tag.c > @@ -322,6 +322,22 @@ int blk_mq_tagset_iter(struct blk_mq_tag_set *set, void > *data, > } > } > > + for (i = 0; i < set->nr_hw_queues; i++) { > + struct blk_mq_tags *sched_tags = set->sched_tags[i]; > + > + if (!sched_tags) > + continue; > + > + for (j = 0; j < sched_tags->nr_tags; j++) { > + if (!sched_tags->static_rqs[j]) > + continue; > + > + ret = fn(data, sched_tags->static_rqs[j]); > + if (ret) > + goto out; > + } > + } > + > out: > return ret; > } > diff --git a/block/blk-mq.c b/block/blk-mq.c > index 7f01d69..d7675b7 100644 > --- a/block/blk-mq.c > +++ b/block/blk-mq.c > @@ -2576,10 +2576,16 @@ int blk_mq_alloc_tag_set(struct blk_mq_tag_set *set) > return -ENOMEM; > > ret = -ENOMEM; > + > + set->sched_tags = kzalloc_node(nr_cpu_ids * sizeof(struct blk_mq_tags > *), > + GFP_KERNEL, set->numa_node); > + if (!set->sched_tags) > + goto out_free_tags; > + > set->mq_map = kzalloc_node(sizeof(*set->mq_map) * nr_cpu_ids, > GFP_KERNEL, set->numa_node); > if (!set->mq_map) > - goto out_free_tags; > + goto out_free_sched_tags; > > ret = blk_mq_update_queue_map(set); > if (ret) > @@ -2597,6 +2603,9 @@ int blk_mq_alloc_tag_set(struct blk_mq_tag_set *set) > out_free_mq_map: > kfree(set->mq_map); > set->mq_map = NULL; > +out_free_sched_tags: > + kfree(set->sched_tags); > + set->sched_tags = NULL; > out_free_tags: > kfree(set->tags); > set->tags = NULL; > @@ -2614,6 +2623,9 @@ void blk_mq_free_tag_set(struct blk_mq_tag_set *set) > kfree(set->mq_map); > set->mq_map = NULL; > > + kfree(set->sched_tags); > + set->sched_tags = NULL; > + > kfree(set->tags); > set->tags = NULL; > } > diff --git a/include/linux/blk-mq.h b/include/linux/blk-mq.h > index cfd64e5..9ec629f 100644 > --- a/include/linux/blk-mq.h > +++ b/include/linux/blk-mq.h > @@ -78,6 +78,7 @@ struct blk_mq_tag_set { > void *driver_data; > > struct blk_mq_tags **tags; > + struct blk_mq_tags **sched_tags;
It isn't a good idea to put 'sched_tags' here because scheduler tags shouldn't be shared, not like driver tags. If you want to do something on scheduler tags, you have to get the 'hctx' instance first. -- Ming
