From 2d10665af8bfa41f772bedc18592b76b96c06729 Mon Sep 17 00:00:00 2001
From: Vu Pham <vu@vu-lt.mti.mtl.com>
Date: Tue, 10 Aug 2010 14:33:51 -0700
Subject: [PATCH 06/10] mlx4: Enable create and attach cq to the vector with least number of cqs already attached
When the vector number passed to mlx4_cq_alloc is MLX4_LEAST_ATTACHED_VECTOR
the driver selects the completion vector that has the least CQs attached
and attaches the CQ to the chosen vector.
IB_CQ_VECTOR_LEAST_ATTACHED is defined in rdma/ib_verbs.h, when mlx4_ib driver
recieves this cq vector number, it uses MLX4_LEAST_ATTACHED_VECTOR to create
the cq
Signed-off-by: Yevgeny Petrilin <yevgenyp@mellanox.co.il>
Signed-off-by: Vu Pham <vu@mellanox.com>
---
drivers/infiniband/hw/mlx4/cq.c | 4 +++-
drivers/net/mlx4/cq.c | 27 +++++++++++++++++++++++----
drivers/net/mlx4/en_cq.c | 2 +-
drivers/net/mlx4/mlx4.h | 1 +
include/linux/mlx4/device.h | 2 ++
include/rdma/ib_verbs.h | 10 +++++++++-
6 files changed, 39 insertions(+), 7 deletions(-)
@@ -223,7 +223,9 @@ struct ib_cq *mlx4_ib_create_cq(struct ib_device *ibdev, int entries, int vector
}
err = mlx4_cq_alloc(dev->dev, entries, &cq->buf.mtt, uar,
- cq->db.dma, &cq->mcq, vector, 0);
+ cq->db.dma, &cq->mcq,
+ vector == IB_CQ_VECTOR_LEAST_ATTACHED ?
+ MLX4_LEAST_ATTACHED_VECTOR : vector, 0);
if (err)
goto err_dbmap;
@@ -187,6 +187,22 @@ int mlx4_cq_resize(struct mlx4_dev *dev, struct mlx4_cq *cq,
}
EXPORT_SYMBOL_GPL(mlx4_cq_resize);
+static int mlx4_find_least_loaded_vector(struct mlx4_priv *priv)
+{
+ int i;
+ int index = 0;
+ int min = priv->eq_table.eq[0].load;
+
+ for (i = 1; i < priv->dev.caps.num_comp_vectors; i++) {
+ if (priv->eq_table.eq[i].load < min) {
+ index = i;
+ min = priv->eq_table.eq[i].load;
+ }
+ }
+
+ return index;
+}
+
int mlx4_cq_alloc(struct mlx4_dev *dev, int nent, struct mlx4_mtt *mtt,
struct mlx4_uar *uar, u64 db_rec, struct mlx4_cq *cq,
unsigned vector, int collapsed)
@@ -198,10 +214,11 @@ int mlx4_cq_alloc(struct mlx4_dev *dev, int nent, struct mlx4_mtt *mtt,
u64 mtt_addr;
int err;
- if (vector >= dev->caps.num_comp_vectors)
- return -EINVAL;
+ cq->vector = (vector == MLX4_LEAST_ATTACHED_VECTOR) ?
+ mlx4_find_least_loaded_vector(priv) : vector;
- cq->vector = vector;
+ if (cq->vector >= dev->caps.num_comp_vectors)
+ return -EINVAL;
cq->cqn = mlx4_bitmap_alloc(&cq_table->bitmap);
if (cq->cqn == -1)
@@ -232,7 +249,7 @@ int mlx4_cq_alloc(struct mlx4_dev *dev, int nent, struct mlx4_mtt *mtt,
cq_context->flags = cpu_to_be32(!!collapsed << 18);
cq_context->logsize_usrpage = cpu_to_be32((ilog2(nent) << 24) | uar->index);
- cq_context->comp_eqn = priv->eq_table.eq[vector].eqn;
+ cq_context->comp_eqn = priv->eq_table.eq[cq->vector].eqn;
cq_context->log_page_size = mtt->page_shift - MLX4_ICM_PAGE_SHIFT;
mtt_addr = mlx4_mtt_addr(dev, mtt);
@@ -245,6 +262,7 @@ int mlx4_cq_alloc(struct mlx4_dev *dev, int nent, struct mlx4_mtt *mtt,
if (err)
goto err_radix;
+ priv->eq_table.eq[cq->vector].load++;
cq->cons_index = 0;
cq->arm_sn = 1;
cq->uar = uar;
@@ -282,6 +300,7 @@ void mlx4_cq_free(struct mlx4_dev *dev, struct mlx4_cq *cq)
mlx4_warn(dev, "HW2SW_CQ failed (%d) for CQN %06x\n", err, cq->cqn);
synchronize_irq(priv->eq_table.eq[cq->vector].irq);
+ priv->eq_table.eq[cq->vector].load--;
spin_lock_irq(&cq_table->lock);
radix_tree_delete(&cq_table->tree, cq->cqn);
@@ -56,7 +56,7 @@ int mlx4_en_create_cq(struct mlx4_en_priv *priv,
cq->vector = ring % mdev->dev->caps.num_comp_vectors;
} else {
cq->buf_size = sizeof(struct mlx4_cqe);
- cq->vector = 0;
+ cq->vector = MLX4_LEAST_ATTACHED_VECTOR;
}
cq->ring = ring;
@@ -137,6 +137,7 @@ struct mlx4_eq {
u16 irq;
u16 have_irq;
int nent;
+ int load;
struct mlx4_buf_list *page_list;
struct mlx4_mtt mtt;
};
@@ -166,6 +166,8 @@ enum mlx4_special_vlan_idx {
MLX4_VLAN_REGULAR
};
+#define MLX4_LEAST_ATTACHED_VECTOR 0xffffffff
+
static inline u64 mlx4_fw_ver(u64 major, u64 minor, u64 subminor)
{
return (major << 32) | (minor << 16) | subminor;
@@ -1462,6 +1462,13 @@ static inline int ib_post_recv(struct ib_qp *qp,
return qp->device->post_recv(qp, recv_wr, bad_recv_wr);
}
+/*
+ * IB_CQ_VECTOR_LEAST_ATTACHED: The constant specifies that
+ * the CQ will be attached to the completion vector that has
+ * the least number of CQs already attached to it.
+ */
+#define IB_CQ_VECTOR_LEAST_ATTACHED 0xffffffff
+
/**
* ib_create_cq - Creates a CQ on the specified device.
* @device: The device on which to create the CQ.
@@ -1473,7 +1480,8 @@ static inline int ib_post_recv(struct ib_qp *qp,
* the associated completion and event handlers.
* @cqe: The minimum size of the CQ.
* @comp_vector - Completion vector used to signal completion events.
- * Must be >= 0 and < context->num_comp_vectors.
+ * Must be >= 0 and < context->num_comp_vectors
+ * or IB_CQ_VECTOR_LEAST_ATTACHED.
*
* Users can examine the cq structure to determine the actual CQ size.
*/
--
1.6.3.3