| Message ID | 1591810159-240929-6-git-send-email-john.garry@huawei.com |
|---|---|
| State | New |
| Headers | show |
| Series | blk-mq/scsi: Provide hostwide shared tags for SCSI HBAs | expand |
On Thu, Jun 11, 2020 at 01:29:12AM +0800, John Garry wrote: > The per-hctx nr_active value can no longer be used to fairly assign a share > of tag depth per request queue for when using a shared sbitmap, as it does > not consider that the tags are shared tags over all hctx's. > > For this case, record the nr_active_requests per request_queue, and make > the judgment based on that value. > > Also introduce a debugfs version of per-hctx blk_mq_debugfs_attr, omitting > hctx_active_show() (as blk_mq_hw_ctx.nr_active is no longer maintained for > the case of shared sbitmap) and other entries which we can add which would > be revised specifically for when using a shared sbitmap. > > Co-developed-with: Kashyap Desai <kashyap.desai@broadcom.com> > Signed-off-by: John Garry <john.garry@huawei.com> > --- > block/blk-core.c | 2 ++ > block/blk-mq-debugfs.c | 23 ++++++++++++++++++++++- > block/blk-mq-tag.c | 10 ++++++---- > block/blk-mq.c | 6 +++--- > block/blk-mq.h | 28 +++++++++++++++++++++++++++- > include/linux/blkdev.h | 2 ++ > 6 files changed, 62 insertions(+), 9 deletions(-) > > diff --git a/block/blk-core.c b/block/blk-core.c > index 03252af8c82c..c622453c1363 100644 > --- a/block/blk-core.c > +++ b/block/blk-core.c > @@ -529,6 +529,8 @@ struct request_queue *__blk_alloc_queue(int node_id) > q->backing_dev_info->capabilities = BDI_CAP_CGROUP_WRITEBACK; > q->node = node_id; > > + atomic_set(&q->nr_active_requests_shared_sbitmap, 0); > + > timer_setup(&q->backing_dev_info->laptop_mode_wb_timer, > laptop_mode_timer_fn, 0); > timer_setup(&q->timeout, blk_rq_timed_out_timer, 0); > diff --git a/block/blk-mq-debugfs.c b/block/blk-mq-debugfs.c > index a400b6698dff..0fa3af41ab65 100644 > --- a/block/blk-mq-debugfs.c > +++ b/block/blk-mq-debugfs.c > @@ -796,6 +796,23 @@ static const struct blk_mq_debugfs_attr blk_mq_debugfs_hctx_attrs[] = { > {}, > }; > > +static const struct blk_mq_debugfs_attr blk_mq_debugfs_hctx_shared_sbitmap_attrs[] = { > + {"state", 0400, hctx_state_show}, > + {"flags", 0400, hctx_flags_show}, > + {"dispatch", 0400, .seq_ops = &hctx_dispatch_seq_ops}, > + {"busy", 0400, hctx_busy_show}, > + {"ctx_map", 0400, hctx_ctx_map_show}, > + {"sched_tags", 0400, hctx_sched_tags_show}, > + {"sched_tags_bitmap", 0400, hctx_sched_tags_bitmap_show}, > + {"io_poll", 0600, hctx_io_poll_show, hctx_io_poll_write}, > + {"dispatched", 0600, hctx_dispatched_show, hctx_dispatched_write}, > + {"queued", 0600, hctx_queued_show, hctx_queued_write}, > + {"run", 0600, hctx_run_show, hctx_run_write}, > + {"active", 0400, hctx_active_show}, > + {"dispatch_busy", 0400, hctx_dispatch_busy_show}, > + {} > +}; You may use macro or whatever to avoid so the duplication. > + > static const struct blk_mq_debugfs_attr blk_mq_debugfs_ctx_attrs[] = { > {"default_rq_list", 0400, .seq_ops = &ctx_default_rq_list_seq_ops}, > {"read_rq_list", 0400, .seq_ops = &ctx_read_rq_list_seq_ops}, > @@ -878,13 +895,17 @@ void blk_mq_debugfs_register_hctx(struct request_queue *q, > struct blk_mq_hw_ctx *hctx) > { > struct blk_mq_ctx *ctx; > + struct blk_mq_tag_set *set = q->tag_set; > char name[20]; > int i; > > snprintf(name, sizeof(name), "hctx%u", hctx->queue_num); > hctx->debugfs_dir = debugfs_create_dir(name, q->debugfs_dir); > > - debugfs_create_files(hctx->debugfs_dir, hctx, blk_mq_debugfs_hctx_attrs); > + if (blk_mq_is_sbitmap_shared(set)) > + debugfs_create_files(hctx->debugfs_dir, hctx, blk_mq_debugfs_hctx_shared_sbitmap_attrs); > + else > + debugfs_create_files(hctx->debugfs_dir, hctx, blk_mq_debugfs_hctx_attrs); > > hctx_for_each_ctx(hctx, ctx, i) > blk_mq_debugfs_register_ctx(hctx, ctx); > diff --git a/block/blk-mq-tag.c b/block/blk-mq-tag.c > index 92843e3e1a2a..7db16e49f6f6 100644 > --- a/block/blk-mq-tag.c > +++ b/block/blk-mq-tag.c > @@ -60,9 +60,11 @@ void __blk_mq_tag_idle(struct blk_mq_hw_ctx *hctx) > * For shared tag users, we track the number of currently active users > * and attempt to provide a fair share of the tag depth for each of them. > */ > -static inline bool hctx_may_queue(struct blk_mq_hw_ctx *hctx, > +static inline bool hctx_may_queue(struct blk_mq_alloc_data *data, > struct sbitmap_queue *bt) > { > + struct blk_mq_hw_ctx *hctx = data->hctx; > + struct request_queue *q = data->q; > unsigned int depth, users; > > if (!hctx || !(hctx->flags & BLK_MQ_F_TAG_QUEUE_SHARED)) > @@ -84,15 +86,15 @@ static inline bool hctx_may_queue(struct blk_mq_hw_ctx *hctx, > * Allow at least some tags > */ > depth = max((bt->sb.depth + users - 1) / users, 4U); > - return atomic_read(&hctx->nr_active) < depth; > + return __blk_mq_active_requests(hctx, q) < depth; There is big change on 'users' too: users = atomic_read(&hctx->tags->active_queues); Originally there is single hctx->tags for these HBAs, now there are many hctx->tags, so 'users' may become much smaller than before. Maybe '->active_queues' can be moved to tag_set for blk_mq_is_sbitmap_shared(). > } > > static int __blk_mq_get_tag(struct blk_mq_alloc_data *data, > struct sbitmap_queue *bt) > { > if (!(data->flags & BLK_MQ_REQ_INTERNAL) && > - !hctx_may_queue(data->hctx, bt)) > - return BLK_MQ_NO_TAG; > + !hctx_may_queue(data, bt)) > + return -1; BLK_MQ_NO_TAG should have been returned. > if (data->shallow_depth) > return __sbitmap_queue_get_shallow(bt, data->shallow_depth); > else > diff --git a/block/blk-mq.c b/block/blk-mq.c > index 77120dd4e4d5..0f7e062a1665 100644 > --- a/block/blk-mq.c > +++ b/block/blk-mq.c > @@ -283,7 +283,7 @@ static struct request *blk_mq_rq_ctx_init(struct blk_mq_alloc_data *data, > } else { > if (data->hctx->flags & BLK_MQ_F_TAG_QUEUE_SHARED) { > rq_flags = RQF_MQ_INFLIGHT; > - atomic_inc(&data->hctx->nr_active); > + __blk_mq_inc_active_requests(data->hctx, data->q); > } > rq->tag = tag; > rq->internal_tag = BLK_MQ_NO_TAG; > @@ -527,7 +527,7 @@ void blk_mq_free_request(struct request *rq) > > ctx->rq_completed[rq_is_sync(rq)]++; > if (rq->rq_flags & RQF_MQ_INFLIGHT) > - atomic_dec(&hctx->nr_active); > + __blk_mq_dec_active_requests(hctx, q); > > if (unlikely(laptop_mode && !blk_rq_is_passthrough(rq))) > laptop_io_completion(q->backing_dev_info); > @@ -1073,7 +1073,7 @@ bool blk_mq_get_driver_tag(struct request *rq) > if (rq->tag >= 0) { > if (shared) { > rq->rq_flags |= RQF_MQ_INFLIGHT; > - atomic_inc(&data.hctx->nr_active); > + __blk_mq_inc_active_requests(rq->mq_hctx, rq->q); > } > data.hctx->tags->rqs[rq->tag] = rq; > } > diff --git a/block/blk-mq.h b/block/blk-mq.h > index 1a283c707215..9c1e612c2298 100644 > --- a/block/blk-mq.h > +++ b/block/blk-mq.h > @@ -202,6 +202,32 @@ static inline bool blk_mq_get_dispatch_budget(struct blk_mq_hw_ctx *hctx) > return true; > } > > +static inline void __blk_mq_inc_active_requests(struct blk_mq_hw_ctx *hctx, > + struct request_queue *q) > +{ > + if (blk_mq_is_sbitmap_shared(q->tag_set)) > + atomic_inc(&q->nr_active_requests_shared_sbitmap); > + else > + atomic_inc(&hctx->nr_active); > +} > + > +static inline void __blk_mq_dec_active_requests(struct blk_mq_hw_ctx *hctx, > + struct request_queue *q) > +{ > + if (blk_mq_is_sbitmap_shared(q->tag_set)) > + atomic_dec(&q->nr_active_requests_shared_sbitmap); > + else > + atomic_dec(&hctx->nr_active); > +} > + > +static inline int __blk_mq_active_requests(struct blk_mq_hw_ctx *hctx, > + struct request_queue *q) > +{ > + if (blk_mq_is_sbitmap_shared(q->tag_set)) I'd suggest to add one hctx version of blk_mq_is_sbitmap_shared() since q->tag_set is seldom used in fast path, and hctx->flags is more efficient than tag_set->flags. Thanks, Ming
>> +static const struct blk_mq_debugfs_attr blk_mq_debugfs_hctx_shared_sbitmap_attrs[] = { >> + {"state", 0400, hctx_state_show}, >> + {"flags", 0400, hctx_flags_show}, >> + {"dispatch", 0400, .seq_ops = &hctx_dispatch_seq_ops}, >> + {"busy", 0400, hctx_busy_show}, >> + {"ctx_map", 0400, hctx_ctx_map_show}, >> + {"sched_tags", 0400, hctx_sched_tags_show}, >> + {"sched_tags_bitmap", 0400, hctx_sched_tags_bitmap_show}, >> + {"io_poll", 0600, hctx_io_poll_show, hctx_io_poll_write}, >> + {"dispatched", 0600, hctx_dispatched_show, hctx_dispatched_write}, >> + {"queued", 0600, hctx_queued_show, hctx_queued_write}, >> + {"run", 0600, hctx_run_show, hctx_run_write}, >> + {"active", 0400, hctx_active_show}, >> + {"dispatch_busy", 0400, hctx_dispatch_busy_show}, >> + {} >> +}; > > You may use macro or whatever to avoid so the duplication. Let me check alternatives. > >> + >> static const struct blk_mq_debugfs_attr blk_mq_debugfs_ctx_attrs[] = { >> {"default_rq_list", 0400, .seq_ops = &ctx_default_rq_list_seq_ops}, >> {"read_rq_list", 0400, .seq_ops = &ctx_read_rq_list_seq_ops}, >> @@ -878,13 +895,17 @@ void blk_mq_debugfs_register_hctx(struct request_queue *q, >> struct blk_mq_hw_ctx *hctx) >> { >> struct blk_mq_ctx *ctx; >> + struct blk_mq_tag_set *set = q->tag_set; >> char name[20]; >> int i; >> >> snprintf(name, sizeof(name), "hctx%u", hctx->queue_num); >> hctx->debugfs_dir = debugfs_create_dir(name, q->debugfs_dir); >> >> - debugfs_create_files(hctx->debugfs_dir, hctx, blk_mq_debugfs_hctx_attrs); >> + if (blk_mq_is_sbitmap_shared(set)) >> + debugfs_create_files(hctx->debugfs_dir, hctx, blk_mq_debugfs_hctx_shared_sbitmap_attrs); >> + else >> + debugfs_create_files(hctx->debugfs_dir, hctx, blk_mq_debugfs_hctx_attrs); >> >> hctx_for_each_ctx(hctx, ctx, i) >> blk_mq_debugfs_register_ctx(hctx, ctx); >> diff --git a/block/blk-mq-tag.c b/block/blk-mq-tag.c >> index 92843e3e1a2a..7db16e49f6f6 100644 >> --- a/block/blk-mq-tag.c >> +++ b/block/blk-mq-tag.c >> @@ -60,9 +60,11 @@ void __blk_mq_tag_idle(struct blk_mq_hw_ctx *hctx) >> * For shared tag users, we track the number of currently active users >> * and attempt to provide a fair share of the tag depth for each of them. >> */ >> -static inline bool hctx_may_queue(struct blk_mq_hw_ctx *hctx, >> +static inline bool hctx_may_queue(struct blk_mq_alloc_data *data, >> struct sbitmap_queue *bt) >> { >> + struct blk_mq_hw_ctx *hctx = data->hctx; >> + struct request_queue *q = data->q; >> unsigned int depth, users; >> >> if (!hctx || !(hctx->flags & BLK_MQ_F_TAG_QUEUE_SHARED)) >> @@ -84,15 +86,15 @@ static inline bool hctx_may_queue(struct blk_mq_hw_ctx *hctx, >> * Allow at least some tags >> */ >> depth = max((bt->sb.depth + users - 1) / users, 4U); >> - return atomic_read(&hctx->nr_active) < depth; >> + return __blk_mq_active_requests(hctx, q) < depth; > > There is big change on 'users' too: > > users = atomic_read(&hctx->tags->active_queues); > > Originally there is single hctx->tags for these HBAs, now there are many > hctx->tags, so 'users' may become much smaller than before. Can you please check how I handled that in the next patch? There we record the number of active request queues per set. (I will note that I could have combined some of these patches, but I liked the piecemeal appraoch, and none of these paths are enabled until later). > > Maybe '->active_queues' can be moved to tag_set for blk_mq_is_sbitmap_shared(). > >> } >> >> static int __blk_mq_get_tag(struct blk_mq_alloc_data *data, >> struct sbitmap_queue *bt) >> { >> if (!(data->flags & BLK_MQ_REQ_INTERNAL) && >> - !hctx_may_queue(data->hctx, bt)) >> - return BLK_MQ_NO_TAG; >> + !hctx_may_queue(data, bt)) >> + return -1; > > BLK_MQ_NO_TAG should have been returned. OK, I missed that in the rebase. > >> if (data->shallow_depth) >> return __sbitmap_queue_get_shallow(bt, data->shallow_depth); >> else >> diff --git a/block/blk-mq.c b/block/blk-mq.c >> index 77120dd4e4d5..0f7e062a1665 100644 >> --- a/block/blk-mq.c >> +++ b/block/blk-mq.c >> @@ -283,7 +283,7 @@ static struct request *blk_mq_rq_ctx_init(struct blk_mq_alloc_data *data, >> } else { >> if (data->hctx->flags & BLK_MQ_F_TAG_QUEUE_SHARED) { >> rq_flags = RQF_MQ_INFLIGHT; >> - atomic_inc(&data->hctx->nr_active); >> + __blk_mq_inc_active_requests(data->hctx, data->q); >> } >> rq->tag = tag; >> rq->internal_tag = BLK_MQ_NO_TAG; >> @@ -527,7 +527,7 @@ void blk_mq_free_request(struct request *rq) >> >> ctx->rq_completed[rq_is_sync(rq)]++; >> if (rq->rq_flags & RQF_MQ_INFLIGHT) >> - atomic_dec(&hctx->nr_active); >> + __blk_mq_dec_active_requests(hctx, q); >> >> if (unlikely(laptop_mode && !blk_rq_is_passthrough(rq))) >> laptop_io_completion(q->backing_dev_info); >> @@ -1073,7 +1073,7 @@ bool blk_mq_get_driver_tag(struct request *rq) >> if (rq->tag >= 0) { >> if (shared) { >> rq->rq_flags |= RQF_MQ_INFLIGHT; >> - atomic_inc(&data.hctx->nr_active); >> + __blk_mq_inc_active_requests(rq->mq_hctx, rq->q); >> } >> data.hctx->tags->rqs[rq->tag] = rq; >> } >> diff --git a/block/blk-mq.h b/block/blk-mq.h >> index 1a283c707215..9c1e612c2298 100644 >> --- a/block/blk-mq.h >> +++ b/block/blk-mq.h >> @@ -202,6 +202,32 @@ static inline bool blk_mq_get_dispatch_budget(struct blk_mq_hw_ctx *hctx) >> return true; >> } >> >> +static inline void __blk_mq_inc_active_requests(struct blk_mq_hw_ctx *hctx, >> + struct request_queue *q) >> +{ >> + if (blk_mq_is_sbitmap_shared(q->tag_set)) >> + atomic_inc(&q->nr_active_requests_shared_sbitmap); >> + else >> + atomic_inc(&hctx->nr_active); >> +} >> + >> +static inline void __blk_mq_dec_active_requests(struct blk_mq_hw_ctx *hctx, >> + struct request_queue *q) >> +{ >> + if (blk_mq_is_sbitmap_shared(q->tag_set)) >> + atomic_dec(&q->nr_active_requests_shared_sbitmap); >> + else >> + atomic_dec(&hctx->nr_active); >> +} >> + >> +static inline int __blk_mq_active_requests(struct blk_mq_hw_ctx *hctx, >> + struct request_queue *q) >> +{ >> + if (blk_mq_is_sbitmap_shared(q->tag_set)) > > I'd suggest to add one hctx version of blk_mq_is_sbitmap_shared() since > q->tag_set is seldom used in fast path, and hctx->flags is more > efficient than tag_set->flags. OK Thanks, John
diff --git a/block/blk-core.c b/block/blk-core.c index 03252af8c82c..c622453c1363 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -529,6 +529,8 @@ struct request_queue *__blk_alloc_queue(int node_id) q->backing_dev_info->capabilities = BDI_CAP_CGROUP_WRITEBACK; q->node = node_id; + atomic_set(&q->nr_active_requests_shared_sbitmap, 0); + timer_setup(&q->backing_dev_info->laptop_mode_wb_timer, laptop_mode_timer_fn, 0); timer_setup(&q->timeout, blk_rq_timed_out_timer, 0); diff --git a/block/blk-mq-debugfs.c b/block/blk-mq-debugfs.c index a400b6698dff..0fa3af41ab65 100644 --- a/block/blk-mq-debugfs.c +++ b/block/blk-mq-debugfs.c @@ -796,6 +796,23 @@ static const struct blk_mq_debugfs_attr blk_mq_debugfs_hctx_attrs[] = { {}, }; +static const struct blk_mq_debugfs_attr blk_mq_debugfs_hctx_shared_sbitmap_attrs[] = { + {"state", 0400, hctx_state_show}, + {"flags", 0400, hctx_flags_show}, + {"dispatch", 0400, .seq_ops = &hctx_dispatch_seq_ops}, + {"busy", 0400, hctx_busy_show}, + {"ctx_map", 0400, hctx_ctx_map_show}, + {"sched_tags", 0400, hctx_sched_tags_show}, + {"sched_tags_bitmap", 0400, hctx_sched_tags_bitmap_show}, + {"io_poll", 0600, hctx_io_poll_show, hctx_io_poll_write}, + {"dispatched", 0600, hctx_dispatched_show, hctx_dispatched_write}, + {"queued", 0600, hctx_queued_show, hctx_queued_write}, + {"run", 0600, hctx_run_show, hctx_run_write}, + {"active", 0400, hctx_active_show}, + {"dispatch_busy", 0400, hctx_dispatch_busy_show}, + {} +}; + static const struct blk_mq_debugfs_attr blk_mq_debugfs_ctx_attrs[] = { {"default_rq_list", 0400, .seq_ops = &ctx_default_rq_list_seq_ops}, {"read_rq_list", 0400, .seq_ops = &ctx_read_rq_list_seq_ops}, @@ -878,13 +895,17 @@ void blk_mq_debugfs_register_hctx(struct request_queue *q, struct blk_mq_hw_ctx *hctx) { struct blk_mq_ctx *ctx; + struct blk_mq_tag_set *set = q->tag_set; char name[20]; int i; snprintf(name, sizeof(name), "hctx%u", hctx->queue_num); hctx->debugfs_dir = debugfs_create_dir(name, q->debugfs_dir); - debugfs_create_files(hctx->debugfs_dir, hctx, blk_mq_debugfs_hctx_attrs); + if (blk_mq_is_sbitmap_shared(set)) + debugfs_create_files(hctx->debugfs_dir, hctx, blk_mq_debugfs_hctx_shared_sbitmap_attrs); + else + debugfs_create_files(hctx->debugfs_dir, hctx, blk_mq_debugfs_hctx_attrs); hctx_for_each_ctx(hctx, ctx, i) blk_mq_debugfs_register_ctx(hctx, ctx); diff --git a/block/blk-mq-tag.c b/block/blk-mq-tag.c index 92843e3e1a2a..7db16e49f6f6 100644 --- a/block/blk-mq-tag.c +++ b/block/blk-mq-tag.c @@ -60,9 +60,11 @@ void __blk_mq_tag_idle(struct blk_mq_hw_ctx *hctx) * For shared tag users, we track the number of currently active users * and attempt to provide a fair share of the tag depth for each of them. */ -static inline bool hctx_may_queue(struct blk_mq_hw_ctx *hctx, +static inline bool hctx_may_queue(struct blk_mq_alloc_data *data, struct sbitmap_queue *bt) { + struct blk_mq_hw_ctx *hctx = data->hctx; + struct request_queue *q = data->q; unsigned int depth, users; if (!hctx || !(hctx->flags & BLK_MQ_F_TAG_QUEUE_SHARED)) @@ -84,15 +86,15 @@ static inline bool hctx_may_queue(struct blk_mq_hw_ctx *hctx, * Allow at least some tags */ depth = max((bt->sb.depth + users - 1) / users, 4U); - return atomic_read(&hctx->nr_active) < depth; + return __blk_mq_active_requests(hctx, q) < depth; } static int __blk_mq_get_tag(struct blk_mq_alloc_data *data, struct sbitmap_queue *bt) { if (!(data->flags & BLK_MQ_REQ_INTERNAL) && - !hctx_may_queue(data->hctx, bt)) - return BLK_MQ_NO_TAG; + !hctx_may_queue(data, bt)) + return -1; if (data->shallow_depth) return __sbitmap_queue_get_shallow(bt, data->shallow_depth); else diff --git a/block/blk-mq.c b/block/blk-mq.c index 77120dd4e4d5..0f7e062a1665 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -283,7 +283,7 @@ static struct request *blk_mq_rq_ctx_init(struct blk_mq_alloc_data *data, } else { if (data->hctx->flags & BLK_MQ_F_TAG_QUEUE_SHARED) { rq_flags = RQF_MQ_INFLIGHT; - atomic_inc(&data->hctx->nr_active); + __blk_mq_inc_active_requests(data->hctx, data->q); } rq->tag = tag; rq->internal_tag = BLK_MQ_NO_TAG; @@ -527,7 +527,7 @@ void blk_mq_free_request(struct request *rq) ctx->rq_completed[rq_is_sync(rq)]++; if (rq->rq_flags & RQF_MQ_INFLIGHT) - atomic_dec(&hctx->nr_active); + __blk_mq_dec_active_requests(hctx, q); if (unlikely(laptop_mode && !blk_rq_is_passthrough(rq))) laptop_io_completion(q->backing_dev_info); @@ -1073,7 +1073,7 @@ bool blk_mq_get_driver_tag(struct request *rq) if (rq->tag >= 0) { if (shared) { rq->rq_flags |= RQF_MQ_INFLIGHT; - atomic_inc(&data.hctx->nr_active); + __blk_mq_inc_active_requests(rq->mq_hctx, rq->q); } data.hctx->tags->rqs[rq->tag] = rq; } diff --git a/block/blk-mq.h b/block/blk-mq.h index 1a283c707215..9c1e612c2298 100644 --- a/block/blk-mq.h +++ b/block/blk-mq.h @@ -202,6 +202,32 @@ static inline bool blk_mq_get_dispatch_budget(struct blk_mq_hw_ctx *hctx) return true; } +static inline void __blk_mq_inc_active_requests(struct blk_mq_hw_ctx *hctx, + struct request_queue *q) +{ + if (blk_mq_is_sbitmap_shared(q->tag_set)) + atomic_inc(&q->nr_active_requests_shared_sbitmap); + else + atomic_inc(&hctx->nr_active); +} + +static inline void __blk_mq_dec_active_requests(struct blk_mq_hw_ctx *hctx, + struct request_queue *q) +{ + if (blk_mq_is_sbitmap_shared(q->tag_set)) + atomic_dec(&q->nr_active_requests_shared_sbitmap); + else + atomic_dec(&hctx->nr_active); +} + +static inline int __blk_mq_active_requests(struct blk_mq_hw_ctx *hctx, + struct request_queue *q) +{ + if (blk_mq_is_sbitmap_shared(q->tag_set)) + return atomic_read(&q->nr_active_requests_shared_sbitmap); + return atomic_read(&hctx->nr_active); +} + static inline void __blk_mq_put_driver_tag(struct blk_mq_hw_ctx *hctx, struct request *rq) { @@ -210,7 +236,7 @@ static inline void __blk_mq_put_driver_tag(struct blk_mq_hw_ctx *hctx, if (rq->rq_flags & RQF_MQ_INFLIGHT) { rq->rq_flags &= ~RQF_MQ_INFLIGHT; - atomic_dec(&hctx->nr_active); + __blk_mq_dec_active_requests(hctx, rq->q); } } diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 8fd900998b4e..c536278bec9e 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -488,6 +488,8 @@ struct request_queue { struct timer_list timeout; struct work_struct timeout_work; + atomic_t nr_active_requests_shared_sbitmap; + struct list_head icq_list; #ifdef CONFIG_BLK_CGROUP DECLARE_BITMAP (blkcg_pols, BLKCG_MAX_POLS);
The per-hctx nr_active value can no longer be used to fairly assign a share of tag depth per request queue for when using a shared sbitmap, as it does not consider that the tags are shared tags over all hctx's. For this case, record the nr_active_requests per request_queue, and make the judgment based on that value. Also introduce a debugfs version of per-hctx blk_mq_debugfs_attr, omitting hctx_active_show() (as blk_mq_hw_ctx.nr_active is no longer maintained for the case of shared sbitmap) and other entries which we can add which would be revised specifically for when using a shared sbitmap. Co-developed-with: Kashyap Desai <kashyap.desai@broadcom.com> Signed-off-by: John Garry <john.garry@huawei.com> --- block/blk-core.c | 2 ++ block/blk-mq-debugfs.c | 23 ++++++++++++++++++++++- block/blk-mq-tag.c | 10 ++++++---- block/blk-mq.c | 6 +++--- block/blk-mq.h | 28 +++++++++++++++++++++++++++- include/linux/blkdev.h | 2 ++ 6 files changed, 62 insertions(+), 9 deletions(-) -- 2.26.2