From bd166ef183c263c5ced656d49ef19c7da4adc774 Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Tue, 17 Jan 2017 06:03:22 -0700 Subject: blk-mq-sched: add framework for MQ capable IO schedulers This adds a set of hooks that intercepts the blk-mq path of allocating/inserting/issuing/completing requests, allowing us to develop a scheduler within that framework. We reuse the existing elevator scheduler API on the registration side, but augment that with the scheduler flagging support for the blk-mq interfce, and with a separate set of ops hooks for MQ devices. We split driver and scheduler tags, so we can run the scheduling independently of device queue depth. Signed-off-by: Jens Axboe Reviewed-by: Bart Van Assche Reviewed-by: Omar Sandoval --- block/blk-cgroup.c | 24 ++++++++++++++++++++---- 1 file changed, 20 insertions(+), 4 deletions(-) (limited to 'block/blk-cgroup.c') diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c index 8ba0af780e88..2630f64bed19 100644 --- a/block/blk-cgroup.c +++ b/block/blk-cgroup.c @@ -1223,7 +1223,11 @@ int blkcg_activate_policy(struct request_queue *q, if (blkcg_policy_enabled(q, pol)) return 0; - blk_queue_bypass_start(q); + if (q->mq_ops) { + blk_mq_freeze_queue(q); + blk_mq_quiesce_queue(q); + } else + blk_queue_bypass_start(q); pd_prealloc: if (!pd_prealloc) { pd_prealloc = pol->pd_alloc_fn(GFP_KERNEL, q->node); @@ -1261,7 +1265,10 @@ pd_prealloc: spin_unlock_irq(q->queue_lock); out_bypass_end: - blk_queue_bypass_end(q); + if (q->mq_ops) + blk_mq_unfreeze_queue(q); + else + blk_queue_bypass_end(q); if (pd_prealloc) pol->pd_free_fn(pd_prealloc); return ret; @@ -1284,7 +1291,12 @@ void blkcg_deactivate_policy(struct request_queue *q, if (!blkcg_policy_enabled(q, pol)) return; - blk_queue_bypass_start(q); + if (q->mq_ops) { + blk_mq_freeze_queue(q); + blk_mq_quiesce_queue(q); + } else + blk_queue_bypass_start(q); + spin_lock_irq(q->queue_lock); __clear_bit(pol->plid, q->blkcg_pols); @@ -1304,7 +1316,11 @@ void blkcg_deactivate_policy(struct request_queue *q, } spin_unlock_irq(q->queue_lock); - blk_queue_bypass_end(q); + + if (q->mq_ops) + blk_mq_unfreeze_queue(q); + else + blk_queue_bypass_end(q); } EXPORT_SYMBOL_GPL(blkcg_deactivate_policy); -- cgit v1.2.3