[PATCH 12/13] nvme: switch to use pci_alloc_irq_vectors

From: Christoph Hellwig
Date: Tue Jun 14 2016 - 16:00:36 EST


This sorts out MSI-X vs MSI vs legacy irq, as well as IRQ affinity
under the hood.

Signed-off-by: Christoph Hellwig <hch@xxxxxx>
---
drivers/nvme/host/pci.c | 89 +++++++++++++------------------------------------
1 file changed, 23 insertions(+), 66 deletions(-)

diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c
index dc39924..96db711 100644
--- a/drivers/nvme/host/pci.c
+++ b/drivers/nvme/host/pci.c
@@ -88,7 +88,6 @@ struct nvme_dev {
unsigned max_qid;
int q_depth;
u32 db_stride;
- struct msix_entry *entry;
void __iomem *bar;
struct work_struct reset_work;
struct work_struct remove_work;
@@ -201,6 +200,11 @@ static unsigned int nvme_cmd_size(struct nvme_dev *dev)
nvme_iod_alloc_size(dev, NVME_INT_BYTES(dev), NVME_INT_PAGES);
}

+static int nvmeq_irq(struct nvme_queue *nvmeq)
+{
+ return to_pci_dev(nvmeq->dev->dev)->irqs[nvmeq->cq_vector];
+}
+
static int nvme_admin_init_hctx(struct blk_mq_hw_ctx *hctx, void *data,
unsigned int hctx_idx)
{
@@ -954,7 +958,7 @@ static int nvme_suspend_queue(struct nvme_queue *nvmeq)
spin_unlock_irq(&nvmeq->q_lock);
return 1;
}
- vector = nvmeq->dev->entry[nvmeq->cq_vector].vector;
+ vector = nvmeq_irq(nvmeq);
nvmeq->dev->online_queues--;
nvmeq->cq_vector = -1;
spin_unlock_irq(&nvmeq->q_lock);
@@ -962,7 +966,6 @@ static int nvme_suspend_queue(struct nvme_queue *nvmeq)
if (!nvmeq->qid && nvmeq->dev->ctrl.admin_q)
blk_mq_stop_hw_queues(nvmeq->dev->ctrl.admin_q);

- irq_set_affinity_hint(vector, NULL);
free_irq(vector, nvmeq);

return 0;
@@ -1073,11 +1076,11 @@ static int queue_request_irq(struct nvme_dev *dev, struct nvme_queue *nvmeq,
const char *name)
{
if (use_threaded_interrupts)
- return request_threaded_irq(dev->entry[nvmeq->cq_vector].vector,
- nvme_irq_check, nvme_irq, IRQF_SHARED,
- name, nvmeq);
- return request_irq(dev->entry[nvmeq->cq_vector].vector, nvme_irq,
- IRQF_SHARED, name, nvmeq);
+ return request_threaded_irq(nvmeq_irq(nvmeq), nvme_irq_check,
+ nvme_irq, IRQF_SHARED, name, nvmeq);
+ else
+ return request_irq(nvmeq_irq(nvmeq), nvme_irq, IRQF_SHARED,
+ name, nvmeq);
}

static void nvme_init_queue(struct nvme_queue *nvmeq, u16 qid)
@@ -1376,7 +1379,7 @@ static int nvme_setup_io_queues(struct nvme_dev *dev)
{
struct nvme_queue *adminq = dev->queues[0];
struct pci_dev *pdev = to_pci_dev(dev->dev);
- int result, i, vecs, nr_io_queues, size;
+ int result, nr_io_queues, size;

nr_io_queues = num_online_cpus();
result = nvme_set_queue_count(&dev->ctrl, &nr_io_queues);
@@ -1411,29 +1414,17 @@ static int nvme_setup_io_queues(struct nvme_dev *dev)
}

/* Deregister the admin queue's interrupt */
- free_irq(dev->entry[0].vector, adminq);
+ free_irq(pdev->irqs[0], adminq);

/*
* If we enable msix early due to not intx, disable it again before
* setting up the full range we need.
*/
- if (pdev->msi_enabled)
- pci_disable_msi(pdev);
- else if (pdev->msix_enabled)
- pci_disable_msix(pdev);
-
- for (i = 0; i < nr_io_queues; i++)
- dev->entry[i].entry = i;
- vecs = pci_enable_msix_range(pdev, dev->entry, 1, nr_io_queues);
- if (vecs < 0) {
- vecs = pci_enable_msi_range(pdev, 1, min(nr_io_queues, 32));
- if (vecs < 0) {
- vecs = 1;
- } else {
- for (i = 0; i < vecs; i++)
- dev->entry[i].vector = i + pdev->irq;
- }
- }
+ pci_free_irq_vectors(pdev);
+ nr_io_queues = pci_alloc_irq_vectors(pdev, 1, nr_io_queues, 0);
+ if (nr_io_queues <= 0)
+ return -EIO;
+ dev->max_qid = nr_io_queues;

/*
* Should investigate if there's a performance win from allocating
@@ -1441,8 +1432,6 @@ static int nvme_setup_io_queues(struct nvme_dev *dev)
* path to scale better, even if the receive path is limited by the
* number of interrupts.
*/
- nr_io_queues = vecs;
- dev->max_qid = nr_io_queues;

result = queue_request_irq(dev, adminq, adminq->irqname);
if (result) {
@@ -1456,23 +1445,6 @@ static int nvme_setup_io_queues(struct nvme_dev *dev)
return result;
}

-static void nvme_pci_post_scan(struct nvme_ctrl *ctrl)
-{
- struct nvme_dev *dev = to_nvme_dev(ctrl);
- struct nvme_queue *nvmeq;
- int i;
-
- for (i = 0; i < dev->online_queues; i++) {
- nvmeq = dev->queues[i];
-
- if (!nvmeq->tags || !(*nvmeq->tags))
- continue;
-
- irq_set_affinity_hint(dev->entry[nvmeq->cq_vector].vector,
- blk_mq_tags_cpumask(*nvmeq->tags));
- }
-}
-
static void nvme_del_queue_end(struct request *req, int error)
{
struct nvme_queue *nvmeq = req->end_io_data;
@@ -1575,6 +1547,7 @@ static int nvme_dev_add(struct nvme_dev *dev)
dev->tagset.cmd_size = nvme_cmd_size(dev);
dev->tagset.flags = BLK_MQ_F_SHOULD_MERGE;
dev->tagset.driver_data = dev;
+ dev->tagset.affinity_mask = to_pci_dev(dev->dev)->irq_affinity;

if (blk_mq_alloc_tag_set(&dev->tagset))
return 0;
@@ -1614,15 +1587,9 @@ static int nvme_pci_enable(struct nvme_dev *dev)
* interrupts. Pre-enable a single MSIX or MSI vec for setup. We'll
* adjust this later.
*/
- if (pci_enable_msix(pdev, dev->entry, 1)) {
- pci_enable_msi(pdev);
- dev->entry[0].vector = pdev->irq;
- }
-
- if (!dev->entry[0].vector) {
- result = -ENODEV;
- goto disable;
- }
+ result = pci_alloc_irq_vectors(pdev, 1, 1, 0);
+ if (result < 0)
+ return result;

cap = lo_hi_readq(dev->bar + NVME_REG_CAP);

@@ -1664,10 +1631,7 @@ static void nvme_pci_disable(struct nvme_dev *dev)
{
struct pci_dev *pdev = to_pci_dev(dev->dev);

- if (pdev->msi_enabled)
- pci_disable_msi(pdev);
- else if (pdev->msix_enabled)
- pci_disable_msix(pdev);
+ pci_free_irq_vectors(pdev);

if (pci_is_enabled(pdev)) {
pci_disable_pcie_error_reporting(pdev);
@@ -1736,7 +1700,6 @@ static void nvme_pci_free_ctrl(struct nvme_ctrl *ctrl)
if (dev->ctrl.admin_q)
blk_put_queue(dev->ctrl.admin_q);
kfree(dev->queues);
- kfree(dev->entry);
kfree(dev);
}

@@ -1879,7 +1842,6 @@ static const struct nvme_ctrl_ops nvme_pci_ctrl_ops = {
.reg_read64 = nvme_pci_reg_read64,
.reset_ctrl = nvme_pci_reset_ctrl,
.free_ctrl = nvme_pci_free_ctrl,
- .post_scan = nvme_pci_post_scan,
.submit_async_event = nvme_pci_submit_async_event,
};

@@ -1916,10 +1878,6 @@ static int nvme_probe(struct pci_dev *pdev, const struct pci_device_id *id)
dev = kzalloc_node(sizeof(*dev), GFP_KERNEL, node);
if (!dev)
return -ENOMEM;
- dev->entry = kzalloc_node(num_possible_cpus() * sizeof(*dev->entry),
- GFP_KERNEL, node);
- if (!dev->entry)
- goto free;
dev->queues = kzalloc_node((num_possible_cpus() + 1) * sizeof(void *),
GFP_KERNEL, node);
if (!dev->queues)
@@ -1960,7 +1918,6 @@ static int nvme_probe(struct pci_dev *pdev, const struct pci_device_id *id)
nvme_dev_unmap(dev);
free:
kfree(dev->queues);
- kfree(dev->entry);
kfree(dev);
return result;
}
--
2.1.4