From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Jens Axboe To: linux-block@vger.kernel.org, linux-nvme@lists.infradead.org, linux-kernel@vger.kernel.org Cc: Jens Axboe Subject: [PATCH 16/16] nvme: add separate poll queue map Date: Tue, 30 Oct 2018 12:32:52 -0600 Message-Id: <20181030183252.17857-17-axboe@kernel.dk> In-Reply-To: <20181030183252.17857-1-axboe@kernel.dk> References: <20181030183252.17857-1-axboe@kernel.dk> List-ID: Adds support for defining a variable number of poll queues, currently configurable with the 'poll_queues' module parameter. Defaults to a single poll queue. And now we finally have poll support without triggering interrupts! Reviewed-by: Hannes Reinecke Signed-off-by: Jens Axboe --- drivers/nvme/host/pci.c | 97 +++++++++++++++++++++++++++++++++-------- include/linux/blk-mq.h | 2 +- 2 files changed, 81 insertions(+), 18 deletions(-) diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c index 17170686105f..305d8d3826d7 100644 --- a/drivers/nvme/host/pci.c +++ b/drivers/nvme/host/pci.c @@ -86,6 +86,10 @@ MODULE_PARM_DESC(write_queues, "Number of queues to use for writes. If not set, reads and writes " "will share a queue set."); +static int poll_queues = 1; +module_param_cb(poll_queues, &queue_count_ops, &poll_queues, 0644); +MODULE_PARM_DESC(poll_queues, "Number of queues to use for polled IO."); + struct nvme_dev; struct nvme_queue; @@ -94,6 +98,7 @@ static void nvme_dev_disable(struct nvme_dev *dev, bool shutdown); enum { NVMEQ_TYPE_READ, NVMEQ_TYPE_WRITE, + NVMEQ_TYPE_POLL, NVMEQ_TYPE_NR, }; @@ -202,6 +207,7 @@ struct nvme_queue { u16 last_cq_head; u16 qid; u8 cq_phase; + u8 polled; u32 *dbbuf_sq_db; u32 *dbbuf_cq_db; u32 *dbbuf_sq_ei; @@ -250,7 +256,7 @@ static inline void _nvme_check_size(void) static unsigned int max_io_queues(void) { - return num_possible_cpus() + write_queues; + return num_possible_cpus() + write_queues + poll_queues; } static unsigned int max_queue_count(void) @@ -500,8 +506,15 @@ static int nvme_pci_map_queues(struct blk_mq_tag_set *set) offset = queue_irq_offset(dev); } + /* + * The poll queue(s) doesn't have an IRQ (and hence IRQ + * affinity), so use the regular blk-mq cpu mapping + */ map->queue_offset = qoff; - blk_mq_pci_map_queues(map, to_pci_dev(dev->dev), offset); + if (i != NVMEQ_TYPE_POLL) + blk_mq_pci_map_queues(map, to_pci_dev(dev->dev), offset); + else + blk_mq_map_queues(map); qoff += map->nr_queues; offset += map->nr_queues; } @@ -892,7 +905,7 @@ static blk_status_t nvme_queue_rq(struct blk_mq_hw_ctx *hctx, * We should not need to do this, but we're still using this to * ensure we can drain requests on a dying queue. */ - if (unlikely(nvmeq->cq_vector < 0)) + if (unlikely(nvmeq->cq_vector < 0 && !nvmeq->polled)) return BLK_STS_IOERR; ret = nvme_setup_cmd(ns, req, &cmnd); @@ -921,6 +934,8 @@ static blk_status_t nvme_queue_rq(struct blk_mq_hw_ctx *hctx, static int nvme_flags_to_type(struct request_queue *q, unsigned int flags) { + if (flags & REQ_HIPRI) + return NVMEQ_TYPE_POLL; if ((flags & REQ_OP_MASK) == REQ_OP_READ) return NVMEQ_TYPE_READ; @@ -1094,7 +1109,10 @@ static int adapter_alloc_cq(struct nvme_dev *dev, u16 qid, struct nvme_queue *nvmeq, s16 vector) { struct nvme_command c; - int flags = NVME_QUEUE_PHYS_CONTIG | NVME_CQ_IRQ_ENABLED; + int flags = NVME_QUEUE_PHYS_CONTIG; + + if (vector != -1) + flags |= NVME_CQ_IRQ_ENABLED; /* * Note: we (ab)use the fact that the prp fields survive if no data @@ -1106,7 +1124,10 @@ static int adapter_alloc_cq(struct nvme_dev *dev, u16 qid, c.create_cq.cqid = cpu_to_le16(qid); c.create_cq.qsize = cpu_to_le16(nvmeq->q_depth - 1); c.create_cq.cq_flags = cpu_to_le16(flags); - c.create_cq.irq_vector = cpu_to_le16(vector); + if (vector != -1) + c.create_cq.irq_vector = cpu_to_le16(vector); + else + c.create_cq.irq_vector = 0; return nvme_submit_sync_cmd(dev->ctrl.admin_q, &c, NULL, 0); } @@ -1348,13 +1369,14 @@ static int nvme_suspend_queue(struct nvme_queue *nvmeq) int vector; spin_lock_irq(&nvmeq->cq_lock); - if (nvmeq->cq_vector == -1) { + if (nvmeq->cq_vector == -1 && !nvmeq->polled) { spin_unlock_irq(&nvmeq->cq_lock); return 1; } vector = nvmeq->cq_vector; nvmeq->dev->online_queues--; nvmeq->cq_vector = -1; + nvmeq->polled = false; spin_unlock_irq(&nvmeq->cq_lock); /* @@ -1366,7 +1388,8 @@ static int nvme_suspend_queue(struct nvme_queue *nvmeq) if (!nvmeq->qid && nvmeq->dev->ctrl.admin_q) blk_mq_quiesce_queue(nvmeq->dev->ctrl.admin_q); - pci_free_irq(to_pci_dev(nvmeq->dev->dev), vector, nvmeq); + if (vector != -1) + pci_free_irq(to_pci_dev(nvmeq->dev->dev), vector, nvmeq); return 0; } @@ -1500,7 +1523,7 @@ static void nvme_init_queue(struct nvme_queue *nvmeq, u16 qid) spin_unlock_irq(&nvmeq->cq_lock); } -static int nvme_create_queue(struct nvme_queue *nvmeq, int qid) +static int nvme_create_queue(struct nvme_queue *nvmeq, int qid, bool polled) { struct nvme_dev *dev = nvmeq->dev; int result; @@ -1510,7 +1533,11 @@ static int nvme_create_queue(struct nvme_queue *nvmeq, int qid) * A queue's vector matches the queue identifier unless the controller * has only one vector available. */ - vector = dev->num_vecs == 1 ? 0 : qid; + if (!polled) + vector = dev->num_vecs == 1 ? 0 : qid; + else + vector = -1; + result = adapter_alloc_cq(dev, qid, nvmeq, vector); if (result) return result; @@ -1527,15 +1554,20 @@ static int nvme_create_queue(struct nvme_queue *nvmeq, int qid) * xxx' warning if the create CQ/SQ command times out. */ nvmeq->cq_vector = vector; + nvmeq->polled = polled; nvme_init_queue(nvmeq, qid); - result = queue_request_irq(nvmeq); - if (result < 0) - goto release_sq; + + if (vector != -1) { + result = queue_request_irq(nvmeq); + if (result < 0) + goto release_sq; + } return result; release_sq: nvmeq->cq_vector = -1; + nvmeq->polled = false; dev->online_queues--; adapter_delete_sq(dev, qid); release_cq: @@ -1686,7 +1718,7 @@ static int nvme_pci_configure_admin_queue(struct nvme_dev *dev) static int nvme_create_io_queues(struct nvme_dev *dev) { - unsigned i, max; + unsigned i, max, rw_queues; int ret = 0; for (i = dev->ctrl.queue_count; i <= dev->max_qid; i++) { @@ -1697,8 +1729,17 @@ static int nvme_create_io_queues(struct nvme_dev *dev) } max = min(dev->max_qid, dev->ctrl.queue_count - 1); + if (max != 1 && dev->io_queues[NVMEQ_TYPE_POLL]) { + rw_queues = dev->io_queues[NVMEQ_TYPE_READ] + + dev->io_queues[NVMEQ_TYPE_WRITE]; + } else { + rw_queues = max; + } + for (i = dev->online_queues; i <= max; i++) { - ret = nvme_create_queue(&dev->queues[i], i); + bool polled = i > rw_queues; + + ret = nvme_create_queue(&dev->queues[i], i, polled); if (ret) break; } @@ -1970,6 +2011,7 @@ static int nvme_setup_host_mem(struct nvme_dev *dev) static void nvme_calc_io_queues(struct nvme_dev *dev, unsigned int nr_io_queues) { unsigned int this_w_queues = write_queues; + unsigned int this_p_queues = poll_queues; /* * Setup read/write queue split @@ -1977,9 +2019,28 @@ static void nvme_calc_io_queues(struct nvme_dev *dev, unsigned int nr_io_queues) if (nr_io_queues == 1) { dev->io_queues[NVMEQ_TYPE_READ] = 1; dev->io_queues[NVMEQ_TYPE_WRITE] = 0; + dev->io_queues[NVMEQ_TYPE_POLL] = 0; return; } + /* + * Configure number of poll queues, if set + */ + if (this_p_queues) { + /* + * We need at least one queue left. With just one queue, we'll + * have a single shared read/write set. + */ + if (this_p_queues >= nr_io_queues) { + this_w_queues = 0; + this_p_queues = nr_io_queues - 1; + } + + dev->io_queues[NVMEQ_TYPE_POLL] = this_p_queues; + nr_io_queues -= this_p_queues; + } else + dev->io_queues[NVMEQ_TYPE_POLL] = 0; + /* * If 'write_queues' is set, ensure it leaves room for at least * one read queue @@ -2084,11 +2145,13 @@ static int nvme_setup_io_queues(struct nvme_dev *dev) } while (1); dev->num_vecs = result; - dev->max_qid = max(result - 1, 1); + result = max(result - 1, 1); + dev->max_qid = result + dev->io_queues[NVMEQ_TYPE_POLL]; - dev_info(dev->ctrl.device, "%d/%d/%d read/write queues\n", + dev_info(dev->ctrl.device, "%d/%d/%d read/write/poll queues\n", dev->io_queues[NVMEQ_TYPE_READ], - dev->io_queues[NVMEQ_TYPE_WRITE]); + dev->io_queues[NVMEQ_TYPE_WRITE], + dev->io_queues[NVMEQ_TYPE_POLL]); /* * Should investigate if there's a performance win from allocating diff --git a/include/linux/blk-mq.h b/include/linux/blk-mq.h index 8e80d5043079..b31f6f016621 100644 --- a/include/linux/blk-mq.h +++ b/include/linux/blk-mq.h @@ -82,7 +82,7 @@ struct blk_mq_queue_map { }; enum { - HCTX_MAX_TYPES = 2, + HCTX_MAX_TYPES = 3, }; struct blk_mq_tag_set { -- 2.17.1 From mboxrd@z Thu Jan 1 00:00:00 1970 From: axboe@kernel.dk (Jens Axboe) Date: Tue, 30 Oct 2018 12:32:52 -0600 Subject: [PATCH 16/16] nvme: add separate poll queue map In-Reply-To: <20181030183252.17857-1-axboe@kernel.dk> References: <20181030183252.17857-1-axboe@kernel.dk> Message-ID: <20181030183252.17857-17-axboe@kernel.dk> Adds support for defining a variable number of poll queues, currently configurable with the 'poll_queues' module parameter. Defaults to a single poll queue. And now we finally have poll support without triggering interrupts! Reviewed-by: Hannes Reinecke Signed-off-by: Jens Axboe --- drivers/nvme/host/pci.c | 97 +++++++++++++++++++++++++++++++++-------- include/linux/blk-mq.h | 2 +- 2 files changed, 81 insertions(+), 18 deletions(-) diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c index 17170686105f..305d8d3826d7 100644 --- a/drivers/nvme/host/pci.c +++ b/drivers/nvme/host/pci.c @@ -86,6 +86,10 @@ MODULE_PARM_DESC(write_queues, "Number of queues to use for writes. If not set, reads and writes " "will share a queue set."); +static int poll_queues = 1; +module_param_cb(poll_queues, &queue_count_ops, &poll_queues, 0644); +MODULE_PARM_DESC(poll_queues, "Number of queues to use for polled IO."); + struct nvme_dev; struct nvme_queue; @@ -94,6 +98,7 @@ static void nvme_dev_disable(struct nvme_dev *dev, bool shutdown); enum { NVMEQ_TYPE_READ, NVMEQ_TYPE_WRITE, + NVMEQ_TYPE_POLL, NVMEQ_TYPE_NR, }; @@ -202,6 +207,7 @@ struct nvme_queue { u16 last_cq_head; u16 qid; u8 cq_phase; + u8 polled; u32 *dbbuf_sq_db; u32 *dbbuf_cq_db; u32 *dbbuf_sq_ei; @@ -250,7 +256,7 @@ static inline void _nvme_check_size(void) static unsigned int max_io_queues(void) { - return num_possible_cpus() + write_queues; + return num_possible_cpus() + write_queues + poll_queues; } static unsigned int max_queue_count(void) @@ -500,8 +506,15 @@ static int nvme_pci_map_queues(struct blk_mq_tag_set *set) offset = queue_irq_offset(dev); } + /* + * The poll queue(s) doesn't have an IRQ (and hence IRQ + * affinity), so use the regular blk-mq cpu mapping + */ map->queue_offset = qoff; - blk_mq_pci_map_queues(map, to_pci_dev(dev->dev), offset); + if (i != NVMEQ_TYPE_POLL) + blk_mq_pci_map_queues(map, to_pci_dev(dev->dev), offset); + else + blk_mq_map_queues(map); qoff += map->nr_queues; offset += map->nr_queues; } @@ -892,7 +905,7 @@ static blk_status_t nvme_queue_rq(struct blk_mq_hw_ctx *hctx, * We should not need to do this, but we're still using this to * ensure we can drain requests on a dying queue. */ - if (unlikely(nvmeq->cq_vector < 0)) + if (unlikely(nvmeq->cq_vector < 0 && !nvmeq->polled)) return BLK_STS_IOERR; ret = nvme_setup_cmd(ns, req, &cmnd); @@ -921,6 +934,8 @@ static blk_status_t nvme_queue_rq(struct blk_mq_hw_ctx *hctx, static int nvme_flags_to_type(struct request_queue *q, unsigned int flags) { + if (flags & REQ_HIPRI) + return NVMEQ_TYPE_POLL; if ((flags & REQ_OP_MASK) == REQ_OP_READ) return NVMEQ_TYPE_READ; @@ -1094,7 +1109,10 @@ static int adapter_alloc_cq(struct nvme_dev *dev, u16 qid, struct nvme_queue *nvmeq, s16 vector) { struct nvme_command c; - int flags = NVME_QUEUE_PHYS_CONTIG | NVME_CQ_IRQ_ENABLED; + int flags = NVME_QUEUE_PHYS_CONTIG; + + if (vector != -1) + flags |= NVME_CQ_IRQ_ENABLED; /* * Note: we (ab)use the fact that the prp fields survive if no data @@ -1106,7 +1124,10 @@ static int adapter_alloc_cq(struct nvme_dev *dev, u16 qid, c.create_cq.cqid = cpu_to_le16(qid); c.create_cq.qsize = cpu_to_le16(nvmeq->q_depth - 1); c.create_cq.cq_flags = cpu_to_le16(flags); - c.create_cq.irq_vector = cpu_to_le16(vector); + if (vector != -1) + c.create_cq.irq_vector = cpu_to_le16(vector); + else + c.create_cq.irq_vector = 0; return nvme_submit_sync_cmd(dev->ctrl.admin_q, &c, NULL, 0); } @@ -1348,13 +1369,14 @@ static int nvme_suspend_queue(struct nvme_queue *nvmeq) int vector; spin_lock_irq(&nvmeq->cq_lock); - if (nvmeq->cq_vector == -1) { + if (nvmeq->cq_vector == -1 && !nvmeq->polled) { spin_unlock_irq(&nvmeq->cq_lock); return 1; } vector = nvmeq->cq_vector; nvmeq->dev->online_queues--; nvmeq->cq_vector = -1; + nvmeq->polled = false; spin_unlock_irq(&nvmeq->cq_lock); /* @@ -1366,7 +1388,8 @@ static int nvme_suspend_queue(struct nvme_queue *nvmeq) if (!nvmeq->qid && nvmeq->dev->ctrl.admin_q) blk_mq_quiesce_queue(nvmeq->dev->ctrl.admin_q); - pci_free_irq(to_pci_dev(nvmeq->dev->dev), vector, nvmeq); + if (vector != -1) + pci_free_irq(to_pci_dev(nvmeq->dev->dev), vector, nvmeq); return 0; } @@ -1500,7 +1523,7 @@ static void nvme_init_queue(struct nvme_queue *nvmeq, u16 qid) spin_unlock_irq(&nvmeq->cq_lock); } -static int nvme_create_queue(struct nvme_queue *nvmeq, int qid) +static int nvme_create_queue(struct nvme_queue *nvmeq, int qid, bool polled) { struct nvme_dev *dev = nvmeq->dev; int result; @@ -1510,7 +1533,11 @@ static int nvme_create_queue(struct nvme_queue *nvmeq, int qid) * A queue's vector matches the queue identifier unless the controller * has only one vector available. */ - vector = dev->num_vecs == 1 ? 0 : qid; + if (!polled) + vector = dev->num_vecs == 1 ? 0 : qid; + else + vector = -1; + result = adapter_alloc_cq(dev, qid, nvmeq, vector); if (result) return result; @@ -1527,15 +1554,20 @@ static int nvme_create_queue(struct nvme_queue *nvmeq, int qid) * xxx' warning if the create CQ/SQ command times out. */ nvmeq->cq_vector = vector; + nvmeq->polled = polled; nvme_init_queue(nvmeq, qid); - result = queue_request_irq(nvmeq); - if (result < 0) - goto release_sq; + + if (vector != -1) { + result = queue_request_irq(nvmeq); + if (result < 0) + goto release_sq; + } return result; release_sq: nvmeq->cq_vector = -1; + nvmeq->polled = false; dev->online_queues--; adapter_delete_sq(dev, qid); release_cq: @@ -1686,7 +1718,7 @@ static int nvme_pci_configure_admin_queue(struct nvme_dev *dev) static int nvme_create_io_queues(struct nvme_dev *dev) { - unsigned i, max; + unsigned i, max, rw_queues; int ret = 0; for (i = dev->ctrl.queue_count; i <= dev->max_qid; i++) { @@ -1697,8 +1729,17 @@ static int nvme_create_io_queues(struct nvme_dev *dev) } max = min(dev->max_qid, dev->ctrl.queue_count - 1); + if (max != 1 && dev->io_queues[NVMEQ_TYPE_POLL]) { + rw_queues = dev->io_queues[NVMEQ_TYPE_READ] + + dev->io_queues[NVMEQ_TYPE_WRITE]; + } else { + rw_queues = max; + } + for (i = dev->online_queues; i <= max; i++) { - ret = nvme_create_queue(&dev->queues[i], i); + bool polled = i > rw_queues; + + ret = nvme_create_queue(&dev->queues[i], i, polled); if (ret) break; } @@ -1970,6 +2011,7 @@ static int nvme_setup_host_mem(struct nvme_dev *dev) static void nvme_calc_io_queues(struct nvme_dev *dev, unsigned int nr_io_queues) { unsigned int this_w_queues = write_queues; + unsigned int this_p_queues = poll_queues; /* * Setup read/write queue split @@ -1977,9 +2019,28 @@ static void nvme_calc_io_queues(struct nvme_dev *dev, unsigned int nr_io_queues) if (nr_io_queues == 1) { dev->io_queues[NVMEQ_TYPE_READ] = 1; dev->io_queues[NVMEQ_TYPE_WRITE] = 0; + dev->io_queues[NVMEQ_TYPE_POLL] = 0; return; } + /* + * Configure number of poll queues, if set + */ + if (this_p_queues) { + /* + * We need at least one queue left. With just one queue, we'll + * have a single shared read/write set. + */ + if (this_p_queues >= nr_io_queues) { + this_w_queues = 0; + this_p_queues = nr_io_queues - 1; + } + + dev->io_queues[NVMEQ_TYPE_POLL] = this_p_queues; + nr_io_queues -= this_p_queues; + } else + dev->io_queues[NVMEQ_TYPE_POLL] = 0; + /* * If 'write_queues' is set, ensure it leaves room for at least * one read queue @@ -2084,11 +2145,13 @@ static int nvme_setup_io_queues(struct nvme_dev *dev) } while (1); dev->num_vecs = result; - dev->max_qid = max(result - 1, 1); + result = max(result - 1, 1); + dev->max_qid = result + dev->io_queues[NVMEQ_TYPE_POLL]; - dev_info(dev->ctrl.device, "%d/%d/%d read/write queues\n", + dev_info(dev->ctrl.device, "%d/%d/%d read/write/poll queues\n", dev->io_queues[NVMEQ_TYPE_READ], - dev->io_queues[NVMEQ_TYPE_WRITE]); + dev->io_queues[NVMEQ_TYPE_WRITE], + dev->io_queues[NVMEQ_TYPE_POLL]); /* * Should investigate if there's a performance win from allocating diff --git a/include/linux/blk-mq.h b/include/linux/blk-mq.h index 8e80d5043079..b31f6f016621 100644 --- a/include/linux/blk-mq.h +++ b/include/linux/blk-mq.h @@ -82,7 +82,7 @@ struct blk_mq_queue_map { }; enum { - HCTX_MAX_TYPES = 2, + HCTX_MAX_TYPES = 3, }; struct blk_mq_tag_set { -- 2.17.1