From 5651cd3c43368873d0787b52acb2e0e08f3c5da4 Mon Sep 17 00:00:00 2001 From: Sagi Grimberg Date: Tue, 28 May 2019 22:49:04 -0700 Subject: [PATCH] nvme-rdma: fix queue mapping when queue count is limited When the controller supports less queues than requested, we should make sure that queue mapping does the right thing and not assume that all queues are available. This fixes a crash when the controller supports less queues than requested. The rules are: 1. if no write/poll queues are requested, we assign the available queues to the default queue map. The default and read queue maps share the existing queues. 2. if write queues are requested: - first make sure that read queue map gets the requested nr_io_queues count - then grant the default queue map the minimum between the requested nr_write_queues and the remaining queues. If there are no available queues to dedicate to the default queue map, fallback to (1) and share all the queues in the existing queue map. 3. if poll queues are requested: - map the remaining queues to the poll queue map. Also, provide a log indication on how we constructed the different queue maps. Reported-by: Harris, James R Reviewed-by: Max Gurtovoy Tested-by: Jim Harris Cc: # v5.0+ Signed-off-by: Sagi Grimberg --- drivers/nvme/host/rdma.c | 99 +++++++++++++++++++++++++++++------------------- 1 file changed, 61 insertions(+), 38 deletions(-) diff --git a/drivers/nvme/host/rdma.c b/drivers/nvme/host/rdma.c index f383146..26709a2 100644 --- a/drivers/nvme/host/rdma.c +++ b/drivers/nvme/host/rdma.c @@ -641,34 +641,16 @@ static int nvme_rdma_alloc_io_queues(struct nvme_rdma_ctrl *ctrl) { struct nvmf_ctrl_options *opts = ctrl->ctrl.opts; struct ib_device *ibdev = ctrl->device->dev; - unsigned int nr_io_queues; + unsigned int nr_io_queues, nr_default_queues; + unsigned int nr_read_queues, nr_poll_queues; int i, ret; - nr_io_queues = min(opts->nr_io_queues, num_online_cpus()); - - /* - * we map queues according to the device irq vectors for - * optimal locality so we don't need more queues than - * completion vectors. - */ - nr_io_queues = min_t(unsigned int, nr_io_queues, - ibdev->num_comp_vectors); - - if (opts->nr_write_queues) { - ctrl->io_queues[HCTX_TYPE_DEFAULT] = - min(opts->nr_write_queues, nr_io_queues); - nr_io_queues += ctrl->io_queues[HCTX_TYPE_DEFAULT]; - } else { - ctrl->io_queues[HCTX_TYPE_DEFAULT] = nr_io_queues; - } - - ctrl->io_queues[HCTX_TYPE_READ] = nr_io_queues; - - if (opts->nr_poll_queues) { - ctrl->io_queues[HCTX_TYPE_POLL] = - min(opts->nr_poll_queues, num_online_cpus()); - nr_io_queues += ctrl->io_queues[HCTX_TYPE_POLL]; - } + nr_read_queues = min_t(unsigned int, ibdev->num_comp_vectors, + min(opts->nr_io_queues, num_online_cpus())); + nr_default_queues = min_t(unsigned int, ibdev->num_comp_vectors, + min(opts->nr_write_queues, num_online_cpus())); + nr_poll_queues = min(opts->nr_poll_queues, num_online_cpus()); + nr_io_queues = nr_read_queues + nr_default_queues + nr_poll_queues; ret = nvme_set_queue_count(&ctrl->ctrl, &nr_io_queues); if (ret) @@ -681,6 +663,34 @@ static int nvme_rdma_alloc_io_queues(struct nvme_rdma_ctrl *ctrl) dev_info(ctrl->ctrl.device, "creating %d I/O queues.\n", nr_io_queues); + if (opts->nr_write_queues && nr_read_queues < nr_io_queues) { + /* + * separate read/write queues + * hand out dedicated default queues only after we have + * sufficient read queues. + */ + ctrl->io_queues[HCTX_TYPE_READ] = nr_read_queues; + nr_io_queues -= ctrl->io_queues[HCTX_TYPE_READ]; + ctrl->io_queues[HCTX_TYPE_DEFAULT] = + min(nr_default_queues, nr_io_queues); + nr_io_queues -= ctrl->io_queues[HCTX_TYPE_DEFAULT]; + } else { + /* + * shared read/write queues + * either no write queues were requested, or we don't have + * sufficient queue count to have dedicated default queues. + */ + ctrl->io_queues[HCTX_TYPE_DEFAULT] = + min(nr_read_queues, nr_io_queues); + nr_io_queues -= ctrl->io_queues[HCTX_TYPE_DEFAULT]; + } + + if (opts->nr_poll_queues && nr_io_queues) { + /* map dedicated poll queues only if we have queues left */ + ctrl->io_queues[HCTX_TYPE_POLL] = + min(nr_poll_queues, nr_io_queues); + } + for (i = 1; i < ctrl->ctrl.queue_count; i++) { ret = nvme_rdma_alloc_queue(ctrl, i, ctrl->ctrl.sqsize + 1); @@ -1763,17 +1773,24 @@ static void nvme_rdma_complete_rq(struct request *rq) static int nvme_rdma_map_queues(struct blk_mq_tag_set *set) { struct nvme_rdma_ctrl *ctrl = set->driver_data; + struct nvmf_ctrl_options *opts = ctrl->ctrl.opts; - set->map[HCTX_TYPE_DEFAULT].queue_offset = 0; - set->map[HCTX_TYPE_DEFAULT].nr_queues = - ctrl->io_queues[HCTX_TYPE_DEFAULT]; - set->map[HCTX_TYPE_READ].nr_queues = ctrl->io_queues[HCTX_TYPE_READ]; - if (ctrl->ctrl.opts->nr_write_queues) { + if (opts->nr_write_queues && ctrl->io_queues[HCTX_TYPE_READ]) { /* separate read/write queues */ + set->map[HCTX_TYPE_DEFAULT].nr_queues = + ctrl->io_queues[HCTX_TYPE_DEFAULT]; + set->map[HCTX_TYPE_DEFAULT].queue_offset = 0; + set->map[HCTX_TYPE_READ].nr_queues = + ctrl->io_queues[HCTX_TYPE_READ]; set->map[HCTX_TYPE_READ].queue_offset = - ctrl->io_queues[HCTX_TYPE_DEFAULT]; + ctrl->io_queues[HCTX_TYPE_DEFAULT]; } else { - /* mixed read/write queues */ + /* shared read/write queues */ + set->map[HCTX_TYPE_DEFAULT].nr_queues = + ctrl->io_queues[HCTX_TYPE_DEFAULT]; + set->map[HCTX_TYPE_DEFAULT].queue_offset = 0; + set->map[HCTX_TYPE_READ].nr_queues = + ctrl->io_queues[HCTX_TYPE_DEFAULT]; set->map[HCTX_TYPE_READ].queue_offset = 0; } blk_mq_rdma_map_queues(&set->map[HCTX_TYPE_DEFAULT], @@ -1781,16 +1798,22 @@ static int nvme_rdma_map_queues(struct blk_mq_tag_set *set) blk_mq_rdma_map_queues(&set->map[HCTX_TYPE_READ], ctrl->device->dev, 0); - if (ctrl->ctrl.opts->nr_poll_queues) { + if (opts->nr_poll_queues && ctrl->io_queues[HCTX_TYPE_POLL]) { + /* map dedicated poll queues only if we have queues left */ set->map[HCTX_TYPE_POLL].nr_queues = ctrl->io_queues[HCTX_TYPE_POLL]; set->map[HCTX_TYPE_POLL].queue_offset = - ctrl->io_queues[HCTX_TYPE_DEFAULT]; - if (ctrl->ctrl.opts->nr_write_queues) - set->map[HCTX_TYPE_POLL].queue_offset += - ctrl->io_queues[HCTX_TYPE_READ]; + ctrl->io_queues[HCTX_TYPE_DEFAULT] + + ctrl->io_queues[HCTX_TYPE_READ]; blk_mq_map_queues(&set->map[HCTX_TYPE_POLL]); } + + dev_info(ctrl->ctrl.device, + "mapped %d/%d/%d default/read/poll queues.\n", + ctrl->io_queues[HCTX_TYPE_DEFAULT], + ctrl->io_queues[HCTX_TYPE_READ], + ctrl->io_queues[HCTX_TYPE_POLL]); + return 0; } -- 2.7.4