From 33023fb85a42b53bf778bc025f9667b582282be4 Mon Sep 17 00:00:00 2001 From: Steve Wise <swise@opengridcomputing.com> Date: Mon, 18 Jun 2018 08:05:26 -0700 Subject: IB/core: add max_send_sge and max_recv_sge attributes This patch replaces the ib_device_attr.max_sge with max_send_sge and max_recv_sge. It allows ulps to take advantage of devices that have very different send and recv sge depths. For example cxgb4 has a max_recv_sge of 4, yet a max_send_sge of 16. Splitting out these attributes allows much more efficient use of the SQ for cxgb4 with ulps that use the RDMA_RW API. Consider a large RDMA WRITE that has 16 scattergather entries. With max_sge of 4, the ulp would send 4 WRITE WRs, but with max_sge of 16, it can be done with 1 WRITE WR. Acked-by: Sagi Grimberg <sagi@grimberg.me> Acked-by: Christoph Hellwig <hch@lst.de> Acked-by: Selvin Xavier <selvin.xavier@broadcom.com> Acked-by: Shiraz Saleem <shiraz.saleem@intel.com> Acked-by: Dennis Dalessandro <dennis.dalessandro@intel.com> Signed-off-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com> --- drivers/infiniband/hw/cxgb4/provider.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'drivers/infiniband/hw/cxgb4/provider.c') diff --git a/drivers/infiniband/hw/cxgb4/provider.c b/drivers/infiniband/hw/cxgb4/provider.c index 1feade8bb4b3..61b8bdb9423d 100644 --- a/drivers/infiniband/hw/cxgb4/provider.c +++ b/drivers/infiniband/hw/cxgb4/provider.c @@ -343,7 +343,8 @@ static int c4iw_query_device(struct ib_device *ibdev, struct ib_device_attr *pro props->max_mr_size = T4_MAX_MR_SIZE; props->max_qp = dev->rdev.lldi.vr->qp.size / 2; props->max_qp_wr = dev->rdev.hw_queue.t4_max_qp_depth; - props->max_sge = T4_MAX_RECV_SGE; + props->max_send_sge = min(T4_MAX_SEND_SGE, T4_MAX_WRITE_SGE); + props->max_recv_sge = T4_MAX_RECV_SGE; props->max_sge_rd = 1; props->max_res_rd_atom = dev->rdev.lldi.max_ird_adapter; props->max_qp_rd_atom = min(dev->rdev.lldi.max_ordird_qp, -- cgit