diff options
author | Keith Busch <keith.busch@intel.com> | 2018-04-12 09:16:10 -0600 |
---|---|---|
committer | Jens Axboe <axboe@kernel.dk> | 2018-04-12 09:58:27 -0600 |
commit | 22b5560195bd66bc43359b71821dc78cc9de56c6 (patch) | |
tree | 4cf28d0850e2533a9ae32e99532b07c5ff42cf64 | |
parent | a6ff7262c26c190f2480721703211cb12d66d45a (diff) |
nvme-pci: Separate IO and admin queue IRQ vectors
The admin and first IO queues shared the first irq vector, which has an
affinity mask including cpu0. If a system allows cpu0 to be offlined,
the admin queue may not be usable if no other CPUs in the affinity mask
are online. This is a problem since unlike IO queues, there is only
one admin queue that always needs to be usable.
To fix, this patch allocates one pre_vector for the admin queue that
is assigned all CPUs, so will always be accessible. The IO queues are
assigned the remaining managed vectors.
In case a controller has only one interrupt vector available, the admin
and IO queues will share the pre_vector with all CPUs assigned.
Cc: Jianchao Wang <jianchao.w.wang@oracle.com>
Cc: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
-rw-r--r-- | drivers/nvme/host/pci.c | 23 |
1 files changed, 17 insertions, 6 deletions
diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c index 0b3b4d9fd423..fbc71fac6f1e 100644 --- a/drivers/nvme/host/pci.c +++ b/drivers/nvme/host/pci.c @@ -84,6 +84,7 @@ struct nvme_dev { struct dma_pool *prp_small_pool; unsigned online_queues; unsigned max_qid; + unsigned int num_vecs; int q_depth; u32 db_stride; void __iomem *bar; @@ -414,7 +415,8 @@ static int nvme_pci_map_queues(struct blk_mq_tag_set *set) { struct nvme_dev *dev = set->driver_data; - return blk_mq_pci_map_queues(set, to_pci_dev(dev->dev), 0); + return blk_mq_pci_map_queues(set, to_pci_dev(dev->dev), + dev->num_vecs > 1 ? 1 /* admin queue */ : 0); } /** @@ -1456,7 +1458,11 @@ static int nvme_create_queue(struct nvme_queue *nvmeq, int qid) nvmeq->sq_cmds_io = dev->cmb + offset; } - nvmeq->cq_vector = qid - 1; + /* + * A queue's vector matches the queue identifier unless the controller + * has only one vector available. + */ + nvmeq->cq_vector = dev->num_vecs == 1 ? 0 : qid; result = adapter_alloc_cq(dev, qid, nvmeq); if (result < 0) goto release_vector; @@ -1910,6 +1916,10 @@ static int nvme_setup_io_queues(struct nvme_dev *dev) int result, nr_io_queues; unsigned long size; + struct irq_affinity affd = { + .pre_vectors = 1 + }; + nr_io_queues = num_possible_cpus(); result = nvme_set_queue_count(&dev->ctrl, &nr_io_queues); if (result < 0) @@ -1945,11 +1955,12 @@ static int nvme_setup_io_queues(struct nvme_dev *dev) * setting up the full range we need. */ pci_free_irq_vectors(pdev); - nr_io_queues = pci_alloc_irq_vectors(pdev, 1, nr_io_queues, - PCI_IRQ_ALL_TYPES | PCI_IRQ_AFFINITY); - if (nr_io_queues <= 0) + result = pci_alloc_irq_vectors_affinity(pdev, 1, nr_io_queues + 1, + PCI_IRQ_ALL_TYPES | PCI_IRQ_AFFINITY, &affd); + if (result <= 0) return -EIO; - dev->max_qid = nr_io_queues; + dev->num_vecs = result; + dev->max_qid = max(result - 1, 1); /* * Should investigate if there's a performance win from allocating |