From: Chaitanya.Kulkarni@wdc.com (Chaitanya Kulkarni)
Subject: [PATCH 14/15] nvme-pci: optimize mapping single segment requests using SGLs
Date: Mon, 25 Mar 2019 05:39:35 +0000 [thread overview]
Message-ID: <SN6PR04MB45274160A60B0803B41190A3865E0@SN6PR04MB4527.namprd04.prod.outlook.com> (raw)
In-Reply-To: 20190321231037.25104-15-hch@lst.de
On 3/21/19 4:12 PM, Christoph Hellwig wrote:
> If the controller supports SGLs we can take another short cut for single
> segment request, given that we can always map those without another
> indirection structure, and thus don't need to create a scatterlist
> structure.
>
> Signed-off-by: Christoph Hellwig <hch at lst.de>
> ---
> drivers/nvme/host/pci.c | 22 ++++++++++++++++++++++
> 1 file changed, 22 insertions(+)
>
> diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c
> index 47fc4d653961..38869f59c296 100644
> --- a/drivers/nvme/host/pci.c
> +++ b/drivers/nvme/host/pci.c
> @@ -819,6 +819,23 @@ static blk_status_t nvme_setup_prp_simple(struct nvme_dev *dev,
> return 0;
> }
>
> +static blk_status_t nvme_setup_sgl_simple(struct nvme_dev *dev,
> + struct request *req, struct nvme_rw_command *cmnd,
> + struct bio_vec *bv)
> +{
> + struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
> +
> + iod->first_dma = dma_map_bvec(dev->dev, bv, rq_dma_dir(req), 0);
> + if (dma_mapping_error(dev->dev, iod->first_dma))
> + return BLK_STS_RESOURCE;
> + iod->dma_len = bv->bv_len;
> +
> + cmnd->dptr.sgl.addr = cpu_to_le64(iod->first_dma);
> + cmnd->dptr.sgl.length = cpu_to_le32(iod->dma_len);
> + cmnd->dptr.sgl.type = NVME_SGL_FMT_DATA_DESC << 4;
> + return 0;
> +}
> +
> static blk_status_t nvme_map_data(struct nvme_dev *dev, struct request *req,
> struct nvme_command *cmnd)
> {
> @@ -836,6 +853,11 @@ static blk_status_t nvme_map_data(struct nvme_dev *dev, struct request *req,
> if (bv.bv_offset + bv.bv_len <= dev->ctrl.page_size * 2)
> return nvme_setup_prp_simple(dev, req,
> &cmnd->rw, &bv);
> +
> + if (iod->nvmeq->qid &&
> + dev->ctrl.sgls & ((1 << 0) | (1 << 1)))
> + return nvme_setup_sgl_simple(dev, req,
> + &cmnd->rw, &bv);
> }
> }
>
>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni at wdc.com>
next prev parent reply other threads:[~2019-03-25 5:39 UTC|newest]
Thread overview: 45+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-03-21 23:10 [RFC] optimize nvme single segment I/O Christoph Hellwig
2019-03-21 23:10 ` [PATCH 01/15] block: add a req_bvec helper Christoph Hellwig
2019-03-25 5:07 ` Chaitanya Kulkarni
2019-03-27 14:16 ` Christoph Hellwig
2019-03-21 23:10 ` [PATCH 02/15] block: add a rq_integrity_vec helper Christoph Hellwig
2019-03-25 5:10 ` Chaitanya Kulkarni
2019-03-27 14:19 ` Christoph Hellwig
2019-03-21 23:10 ` [PATCH 03/15] block: add a rq_dma_dir helper Christoph Hellwig
2019-03-22 13:06 ` Johannes Thumshirn
2019-03-27 14:20 ` Christoph Hellwig
2019-03-28 10:26 ` Johannes Thumshirn
2019-03-25 5:11 ` Chaitanya Kulkarni
2019-03-21 23:10 ` [PATCH 04/15] block: add dma_map_bvec helper Christoph Hellwig
2019-03-25 5:13 ` Chaitanya Kulkarni
2019-03-21 23:10 ` [PATCH 05/15] nvme-pci: remove the unused iod->length field Christoph Hellwig
2019-03-25 5:14 ` Chaitanya Kulkarni
2019-03-21 23:10 ` [PATCH 06/15] nvme-pci: remove nvme_init_iod Christoph Hellwig
2019-03-25 5:19 ` Chaitanya Kulkarni
2019-03-27 14:21 ` Christoph Hellwig
2019-03-21 23:10 ` [PATCH 07/15] nvme-pci: move the call to nvme_cleanup_cmd out of nvme_unmap_data Christoph Hellwig
2019-03-25 5:21 ` Chaitanya Kulkarni
2019-03-21 23:10 ` [PATCH 08/15] nvme-pci: merge nvme_free_iod into nvme_unmap_data Christoph Hellwig
2019-03-25 5:22 ` Chaitanya Kulkarni
2019-03-21 23:10 ` [PATCH 09/15] nvme-pci: only call nvme_unmap_data for requests transferring data Christoph Hellwig
2019-03-25 5:23 ` Chaitanya Kulkarni
2019-03-21 23:10 ` [PATCH 10/15] nvme-pci: do not build a scatterlist to map metadata Christoph Hellwig
2019-03-25 5:27 ` Chaitanya Kulkarni
[not found] ` <20190828092057.GA15524@ming.t460p>
2019-09-12 1:02 ` Ming Lei
2019-09-12 8:20 ` Christoph Hellwig
2019-03-21 23:10 ` [PATCH 11/15] nvme-pci: split metadata handling from nvme_map_data / nvme_unmap_data Christoph Hellwig
2019-03-25 5:29 ` Chaitanya Kulkarni
2019-03-21 23:10 ` [PATCH 12/15] nvme-pci: remove the inline scatterlist optimization Christoph Hellwig
2019-03-25 5:30 ` Chaitanya Kulkarni
2019-03-21 23:10 ` [PATCH 13/15] nvme-pci: optimize mapping of small single segment requests Christoph Hellwig
2019-03-25 5:36 ` Chaitanya Kulkarni
2019-03-21 23:10 ` [PATCH 14/15] nvme-pci: optimize mapping single segment requests using SGLs Christoph Hellwig
2019-03-25 5:39 ` Chaitanya Kulkarni [this message]
2019-04-30 14:17 ` Klaus Birkelund
2019-04-30 14:32 ` Christoph Hellwig
2019-03-21 23:10 ` [PATCH 15/15] nvme-pci: tidy up nvme_map_data Christoph Hellwig
2019-03-25 5:40 ` Chaitanya Kulkarni
2019-03-22 15:44 ` [RFC] optimize nvme single segment I/O Jens Axboe
2019-03-27 14:24 ` Christoph Hellwig
2019-03-22 17:37 ` Keith Busch
2019-03-22 18:55 ` Sagi Grimberg
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