diff options
Diffstat (limited to 'drivers/infiniband/core/cq.c')
| -rw-r--r-- | drivers/infiniband/core/cq.c | 173 |
1 files changed, 173 insertions, 0 deletions
diff --git a/drivers/infiniband/core/cq.c b/drivers/infiniband/core/cq.c index 4f25b2400694..655795bfa0ee 100644 --- a/drivers/infiniband/core/cq.c +++ b/drivers/infiniband/core/cq.c @@ -7,7 +7,11 @@ #include <linux/slab.h> #include <rdma/ib_verbs.h> +#include "core_priv.h" + #include <trace/events/rdma_core.h> +/* Max size for shared CQ, may require tuning */ +#define IB_MAX_SHARED_CQ_SZ 4096U /* # of WCs to poll for with a single call to ib_poll_cq */ #define IB_POLL_BATCH 16 @@ -218,6 +222,7 @@ struct ib_cq *__ib_alloc_cq_user(struct ib_device *dev, void *private, cq->cq_context = private; cq->poll_ctx = poll_ctx; atomic_set(&cq->usecnt, 0); + cq->comp_vector = comp_vector; cq->wc = kmalloc_array(IB_POLL_BATCH, sizeof(*cq->wc), GFP_KERNEL); if (!cq->wc) @@ -309,6 +314,8 @@ void ib_free_cq_user(struct ib_cq *cq, struct ib_udata *udata) { if (WARN_ON_ONCE(atomic_read(&cq->usecnt))) return; + if (WARN_ON_ONCE(cq->cqe_used)) + return; switch (cq->poll_ctx) { case IB_POLL_DIRECT: @@ -334,3 +341,169 @@ void ib_free_cq_user(struct ib_cq *cq, struct ib_udata *udata) kfree(cq); } EXPORT_SYMBOL(ib_free_cq_user); + +void ib_cq_pool_init(struct ib_device *dev) +{ + unsigned int i; + + spin_lock_init(&dev->cq_pools_lock); + for (i = 0; i < ARRAY_SIZE(dev->cq_pools); i++) + INIT_LIST_HEAD(&dev->cq_pools[i]); +} + +void ib_cq_pool_destroy(struct ib_device *dev) +{ + struct ib_cq *cq, *n; + unsigned int i; + + for (i = 0; i < ARRAY_SIZE(dev->cq_pools); i++) { + list_for_each_entry_safe(cq, n, &dev->cq_pools[i], + pool_entry) { + WARN_ON(cq->cqe_used); + cq->shared = false; + ib_free_cq(cq); + } + } +} + +static int ib_alloc_cqs(struct ib_device *dev, unsigned int nr_cqes, + enum ib_poll_context poll_ctx) +{ + LIST_HEAD(tmp_list); + unsigned int nr_cqs, i; + struct ib_cq *cq; + int ret; + + if (poll_ctx > IB_POLL_LAST_POOL_TYPE) { + WARN_ON_ONCE(poll_ctx > IB_POLL_LAST_POOL_TYPE); + return -EINVAL; + } + + /* + * Allocate at least as many CQEs as requested, and otherwise + * a reasonable batch size so that we can share CQs between + * multiple users instead of allocating a larger number of CQs. + */ + nr_cqes = min_t(unsigned int, dev->attrs.max_cqe, + max(nr_cqes, IB_MAX_SHARED_CQ_SZ)); + nr_cqs = min_t(unsigned int, dev->num_comp_vectors, num_online_cpus()); + for (i = 0; i < nr_cqs; i++) { + cq = ib_alloc_cq(dev, NULL, nr_cqes, i, poll_ctx); + if (IS_ERR(cq)) { + ret = PTR_ERR(cq); + goto out_free_cqs; + } + cq->shared = true; + list_add_tail(&cq->pool_entry, &tmp_list); + } + + spin_lock_irq(&dev->cq_pools_lock); + list_splice(&tmp_list, &dev->cq_pools[poll_ctx]); + spin_unlock_irq(&dev->cq_pools_lock); + + return 0; + +out_free_cqs: + list_for_each_entry(cq, &tmp_list, pool_entry) { + cq->shared = false; + ib_free_cq(cq); + } + return ret; +} + +/** + * ib_cq_pool_get() - Find the least used completion queue that matches + * a given cpu hint (or least used for wild card affinity) and fits + * nr_cqe. + * @dev: rdma device + * @nr_cqe: number of needed cqe entries + * @comp_vector_hint: completion vector hint (-1) for the driver to assign + * a comp vector based on internal counter + * @poll_ctx: cq polling context + * + * Finds a cq that satisfies @comp_vector_hint and @nr_cqe requirements and + * claim entries in it for us. In case there is no available cq, allocate + * a new cq with the requirements and add it to the device pool. + * IB_POLL_DIRECT cannot be used for shared cqs so it is not a valid value + * for @poll_ctx. + */ +struct ib_cq *ib_cq_pool_get(struct ib_device *dev, unsigned int nr_cqe, + int comp_vector_hint, + enum ib_poll_context poll_ctx) +{ + static unsigned int default_comp_vector; + unsigned int vector, num_comp_vectors; + struct ib_cq *cq, *found = NULL; + int ret; + + if (poll_ctx > IB_POLL_LAST_POOL_TYPE) { + WARN_ON_ONCE(poll_ctx > IB_POLL_LAST_POOL_TYPE); + return ERR_PTR(-EINVAL); + } + + num_comp_vectors = + min_t(unsigned int, dev->num_comp_vectors, num_online_cpus()); + /* Project the affinty to the device completion vector range */ + if (comp_vector_hint < 0) { + comp_vector_hint = + (READ_ONCE(default_comp_vector) + 1) % num_comp_vectors; + WRITE_ONCE(default_comp_vector, comp_vector_hint); + } + vector = comp_vector_hint % num_comp_vectors; + + /* + * Find the least used CQ with correct affinity and + * enough free CQ entries + */ + while (!found) { + spin_lock_irq(&dev->cq_pools_lock); + list_for_each_entry(cq, &dev->cq_pools[poll_ctx], + pool_entry) { + /* + * Check to see if we have found a CQ with the + * correct completion vector + */ + if (vector != cq->comp_vector) + continue; + if (cq->cqe_used + nr_cqe > cq->cqe) + continue; + found = cq; + break; + } + + if (found) { + found->cqe_used += nr_cqe; + spin_unlock_irq(&dev->cq_pools_lock); + + return found; + } + spin_unlock_irq(&dev->cq_pools_lock); + + /* + * Didn't find a match or ran out of CQs in the device + * pool, allocate a new array of CQs. + */ + ret = ib_alloc_cqs(dev, nr_cqe, poll_ctx); + if (ret) + return ERR_PTR(ret); + } + + return found; +} +EXPORT_SYMBOL(ib_cq_pool_get); + +/** + * ib_cq_pool_put - Return a CQ taken from a shared pool. + * @cq: The CQ to return. + * @nr_cqe: The max number of cqes that the user had requested. + */ +void ib_cq_pool_put(struct ib_cq *cq, unsigned int nr_cqe) +{ + if (WARN_ON_ONCE(nr_cqe > cq->cqe_used)) + return; + + spin_lock_irq(&cq->device->cq_pools_lock); + cq->cqe_used -= nr_cqe; + spin_unlock_irq(&cq->device->cq_pools_lock); +} +EXPORT_SYMBOL(ib_cq_pool_put); |