diff options
| -rw-r--r-- | drivers/block/nvme-core.c | 204 | ||||
| -rw-r--r-- | include/linux/nvme.h | 6 |
2 files changed, 172 insertions, 38 deletions
diff --git a/drivers/block/nvme-core.c b/drivers/block/nvme-core.c index e9495f0bfad3..48d7bd55207a 100644 --- a/drivers/block/nvme-core.c +++ b/drivers/block/nvme-core.c @@ -20,6 +20,7 @@ #include <linux/bio.h> #include <linux/bitops.h> #include <linux/blkdev.h> +#include <linux/cpu.h> #include <linux/delay.h> #include <linux/errno.h> #include <linux/fs.h> @@ -35,6 +36,7 @@ #include <linux/module.h> #include <linux/moduleparam.h> #include <linux/pci.h> +#include <linux/percpu.h> #include <linux/poison.h> #include <linux/ptrace.h> #include <linux/sched.h> @@ -96,6 +98,7 @@ struct nvme_queue { u8 cq_phase; u8 cqe_seen; u8 q_suspended; + cpumask_var_t cpu_mask; struct async_cmd_info cmdinfo; unsigned long cmdid_data[]; }; @@ -270,14 +273,15 @@ static struct nvme_queue *raw_nvmeq(struct nvme_dev *dev, int qid) static struct nvme_queue *get_nvmeq(struct nvme_dev *dev) __acquires(RCU) { + unsigned queue_id = get_cpu_var(*dev->io_queue); rcu_read_lock(); - return rcu_dereference(dev->queues[get_cpu() + 1]); + return rcu_dereference(dev->queues[queue_id]); } static void put_nvmeq(struct nvme_queue *nvmeq) __releases(RCU) { - put_cpu(); rcu_read_unlock(); + put_cpu_var(nvmeq->dev->io_queue); } static struct nvme_queue *lock_nvmeq(struct nvme_dev *dev, int q_idx) @@ -1121,6 +1125,8 @@ static void nvme_free_queue(struct rcu_head *r) (void *)nvmeq->cqes, nvmeq->cq_dma_addr); dma_free_coherent(nvmeq->q_dmadev, SQ_SIZE(nvmeq->q_depth), nvmeq->sq_cmds, nvmeq->sq_dma_addr); + if (nvmeq->qid) + free_cpumask_var(nvmeq->cpu_mask); kfree(nvmeq); } @@ -1128,8 +1134,6 @@ static void nvme_free_queues(struct nvme_dev *dev, int lowest) { int i; - for (i = num_possible_cpus(); i > dev->queue_count - 1; i--) - rcu_assign_pointer(dev->queues[i], NULL); for (i = dev->queue_count - 1; i >= lowest; i--) { struct nvme_queue *nvmeq = raw_nvmeq(dev, i); rcu_assign_pointer(dev->queues[i], NULL); @@ -1154,6 +1158,7 @@ static int nvme_suspend_queue(struct nvme_queue *nvmeq) return 1; } nvmeq->q_suspended = 1; + nvmeq->dev->online_queues--; spin_unlock_irq(&nvmeq->q_lock); irq_set_affinity_hint(vector, NULL); @@ -1208,6 +1213,9 @@ static struct nvme_queue *nvme_alloc_queue(struct nvme_dev *dev, int qid, if (!nvmeq->sq_cmds) goto free_cqdma; + if (qid && !zalloc_cpumask_var(&nvmeq->cpu_mask, GFP_KERNEL)) + goto free_sqdma; + nvmeq->q_dmadev = dmadev; nvmeq->dev = dev; snprintf(nvmeq->irqname, sizeof(nvmeq->irqname), "nvme%dq%d", @@ -1228,6 +1236,9 @@ static struct nvme_queue *nvme_alloc_queue(struct nvme_dev *dev, int qid, return nvmeq; + free_sqdma: + dma_free_coherent(dmadev, SQ_SIZE(depth), (void *)nvmeq->sq_cmds, + nvmeq->sq_dma_addr); free_cqdma: dma_free_coherent(dmadev, CQ_SIZE(depth), (void *)nvmeq->cqes, nvmeq->cq_dma_addr); @@ -1260,6 +1271,7 @@ static void nvme_init_queue(struct nvme_queue *nvmeq, u16 qid) memset((void *)nvmeq->cqes, 0, CQ_SIZE(nvmeq->q_depth)); nvme_cancel_ios(nvmeq, false); nvmeq->q_suspended = 0; + dev->online_queues++; } static int nvme_create_queue(struct nvme_queue *nvmeq, int qid) @@ -1835,6 +1847,143 @@ static struct nvme_ns *nvme_alloc_ns(struct nvme_dev *dev, unsigned nsid, return NULL; } +static int nvme_find_closest_node(int node) +{ + int n, val, min_val = INT_MAX, best_node = node; + + for_each_online_node(n) { + if (n == node) + continue; + val = node_distance(node, n); + if (val < min_val) { + min_val = val; + best_node = n; + } + } + return best_node; +} + +static void nvme_set_queue_cpus(cpumask_t *qmask, struct nvme_queue *nvmeq, + int count) +{ + int cpu; + for_each_cpu(cpu, qmask) { + if (cpumask_weight(nvmeq->cpu_mask) >= count) + break; + if (!cpumask_test_and_set_cpu(cpu, nvmeq->cpu_mask)) + *per_cpu_ptr(nvmeq->dev->io_queue, cpu) = nvmeq->qid; + } +} + +static void nvme_add_cpus(cpumask_t *mask, const cpumask_t *unassigned_cpus, + const cpumask_t *new_mask, struct nvme_queue *nvmeq, int cpus_per_queue) +{ + int next_cpu; + for_each_cpu(next_cpu, new_mask) { + cpumask_or(mask, mask, get_cpu_mask(next_cpu)); + cpumask_or(mask, mask, topology_thread_cpumask(next_cpu)); + cpumask_and(mask, mask, unassigned_cpus); + nvme_set_queue_cpus(mask, nvmeq, cpus_per_queue); + } +} + +static void nvme_create_io_queues(struct nvme_dev *dev) +{ + unsigned i, max; + + max = min(dev->max_qid, num_online_cpus()); + for (i = dev->queue_count; i <= max; i++) + if (!nvme_alloc_queue(dev, i, dev->q_depth, i - 1)) + break; + + max = min(dev->queue_count - 1, num_online_cpus()); + for (i = dev->online_queues; i <= max; i++) + if (nvme_create_queue(raw_nvmeq(dev, i), i)) + break; +} + +/* + * If there are fewer queues than online cpus, this will try to optimally + * assign a queue to multiple cpus by grouping cpus that are "close" together: + * thread siblings, core, socket, closest node, then whatever else is + * available. + */ +static void nvme_assign_io_queues(struct nvme_dev *dev) +{ + unsigned cpu, cpus_per_queue, queues, remainder, i; + cpumask_var_t unassigned_cpus; + + nvme_create_io_queues(dev); + + queues = min(dev->online_queues - 1, num_online_cpus()); + if (!queues) + return; + + cpus_per_queue = num_online_cpus() / queues; + remainder = queues - (num_online_cpus() - queues * cpus_per_queue); + + if (!alloc_cpumask_var(&unassigned_cpus, GFP_KERNEL)) + return; + + cpumask_copy(unassigned_cpus, cpu_online_mask); + cpu = cpumask_first(unassigned_cpus); + for (i = 1; i <= queues; i++) { + struct nvme_queue *nvmeq = lock_nvmeq(dev, i); + cpumask_t mask; + + cpumask_clear(nvmeq->cpu_mask); + if (!cpumask_weight(unassigned_cpus)) { + unlock_nvmeq(nvmeq); + break; + } + + mask = *get_cpu_mask(cpu); + nvme_set_queue_cpus(&mask, nvmeq, cpus_per_queue); + if (cpus_weight(mask) < cpus_per_queue) + nvme_add_cpus(&mask, unassigned_cpus, + topology_thread_cpumask(cpu), + nvmeq, cpus_per_queue); + if (cpus_weight(mask) < cpus_per_queue) + nvme_add_cpus(&mask, unassigned_cpus, + topology_core_cpumask(cpu), + nvmeq, cpus_per_queue); + if (cpus_weight(mask) < cpus_per_queue) + nvme_add_cpus(&mask, unassigned_cpus, + cpumask_of_node(cpu_to_node(cpu)), + nvmeq, cpus_per_queue); + if (cpus_weight(mask) < cpus_per_queue) + nvme_add_cpus(&mask, unassigned_cpus, + cpumask_of_node( + nvme_find_closest_node( + cpu_to_node(cpu))), + nvmeq, cpus_per_queue); + if (cpus_weight(mask) < cpus_per_queue) + nvme_add_cpus(&mask, unassigned_cpus, + unassigned_cpus, + nvmeq, cpus_per_queue); + + WARN(cpumask_weight(nvmeq->cpu_mask) != cpus_per_queue, + "nvme%d qid:%d mis-matched queue-to-cpu assignment\n", + dev->instance, i); + + irq_set_affinity_hint(dev->entry[nvmeq->cq_vector].vector, + nvmeq->cpu_mask); + cpumask_andnot(unassigned_cpus, unassigned_cpus, + nvmeq->cpu_mask); + cpu = cpumask_next(cpu, unassigned_cpus); + if (remainder && !--remainder) + cpus_per_queue++; + unlock_nvmeq(nvmeq); + } + WARN(cpumask_weight(unassigned_cpus), "nvme%d unassigned online cpus\n", + dev->instance); + i = 0; + cpumask_andnot(unassigned_cpus, cpu_possible_mask, cpu_online_mask); + for_each_cpu(cpu, unassigned_cpus) + *per_cpu_ptr(dev->io_queue, cpu) = (i++ % queues) + 1; + free_cpumask_var(unassigned_cpus); +} + static int set_queue_count(struct nvme_dev *dev, int count) { int status; @@ -1857,9 +2006,9 @@ static int nvme_setup_io_queues(struct nvme_dev *dev) { struct nvme_queue *adminq = raw_nvmeq(dev, 0); struct pci_dev *pdev = dev->pci_dev; - int result, cpu, i, vecs, nr_io_queues, size, q_depth; + int result, i, vecs, nr_io_queues, size; - nr_io_queues = num_online_cpus(); + nr_io_queues = num_possible_cpus(); result = set_queue_count(dev, nr_io_queues); if (result < 0) return result; @@ -1919,6 +2068,7 @@ static int nvme_setup_io_queues(struct nvme_dev *dev) * number of interrupts. */ nr_io_queues = vecs; + dev->max_qid = nr_io_queues; result = queue_request_irq(dev, adminq, adminq->irqname); if (result) { @@ -1927,36 +2077,8 @@ static int nvme_setup_io_queues(struct nvme_dev *dev) } /* Free previously allocated queues that are no longer usable */ - nvme_free_queues(dev, nr_io_queues); - - cpu = cpumask_first(cpu_online_mask); - for (i = 0; i < nr_io_queues; i++) { - irq_set_affinity_hint(dev->entry[i].vector, get_cpu_mask(cpu)); - cpu = cpumask_next(cpu, cpu_online_mask); - } - - q_depth = min_t(int, NVME_CAP_MQES(readq(&dev->bar->cap)) + 1, - NVME_Q_DEPTH); - for (i = dev->queue_count - 1; i < nr_io_queues; i++) { - if (!nvme_alloc_queue(dev, i + 1, q_depth, i)) { - result = -ENOMEM; - goto free_queues; - } - } - - for (; i < num_possible_cpus(); i++) { - int target = i % rounddown_pow_of_two(dev->queue_count - 1); - rcu_assign_pointer(dev->queues[i + 1], dev->queues[target + 1]); - } - - for (i = 1; i < dev->queue_count; i++) { - result = nvme_create_queue(raw_nvmeq(dev, i), i); - if (result) { - for (--i; i > 0; i--) - nvme_disable_queue(dev, i); - goto free_queues; - } - } + nvme_free_queues(dev, nr_io_queues + 1); + nvme_assign_io_queues(dev); return 0; @@ -2035,6 +2157,7 @@ static int nvme_dev_add(struct nvme_dev *dev) static int nvme_dev_map(struct nvme_dev *dev) { + u64 cap; int bars, result = -ENOMEM; struct pci_dev *pdev = dev->pci_dev; @@ -2058,7 +2181,9 @@ static int nvme_dev_map(struct nvme_dev *dev) result = -ENODEV; goto unmap; } - dev->db_stride = 1 << NVME_CAP_STRIDE(readq(&dev->bar->cap)); + cap = readq(&dev->bar->cap); + dev->q_depth = min_t(int, NVME_CAP_MQES(cap) + 1, NVME_Q_DEPTH); + dev->db_stride = 1 << NVME_CAP_STRIDE(cap); dev->dbs = ((void __iomem *)dev->bar) + 4096; return 0; @@ -2332,6 +2457,7 @@ static void nvme_free_dev(struct kref *kref) struct nvme_dev *dev = container_of(kref, struct nvme_dev, kref); nvme_free_namespaces(dev); + free_percpu(dev->io_queue); kfree(dev->queues); kfree(dev->entry); kfree(dev); @@ -2477,6 +2603,9 @@ static int nvme_probe(struct pci_dev *pdev, const struct pci_device_id *id) GFP_KERNEL); if (!dev->queues) goto free; + dev->io_queue = alloc_percpu(unsigned short); + if (!dev->io_queue) + goto free; INIT_LIST_HEAD(&dev->namespaces); INIT_WORK(&dev->reset_work, nvme_reset_failed_dev); @@ -2526,6 +2655,7 @@ static int nvme_probe(struct pci_dev *pdev, const struct pci_device_id *id) release: nvme_release_instance(dev); free: + free_percpu(dev->io_queue); kfree(dev->queues); kfree(dev->entry); kfree(dev); diff --git a/include/linux/nvme.h b/include/linux/nvme.h index 7c3f85bc10f1..f0f95c719685 100644 --- a/include/linux/nvme.h +++ b/include/linux/nvme.h @@ -74,12 +74,16 @@ enum { struct nvme_dev { struct list_head node; struct nvme_queue __rcu **queues; + unsigned short __percpu *io_queue; u32 __iomem *dbs; struct pci_dev *pci_dev; struct dma_pool *prp_page_pool; struct dma_pool *prp_small_pool; int instance; - int queue_count; + unsigned queue_count; + unsigned online_queues; + unsigned max_qid; + int q_depth; u32 db_stride; u32 ctrl_config; struct msix_entry *entry; |