[PATCH rdma-next 4/6] net/rds: Avoid calling ib_query_device

Or Gerlitz
2015-12-17T13:18:58Z

Instead, use the cached copy of the attributes present on the device.

Based on a patch from Christoph Hellwig <hch-jcswGhMUV9g@public.gmane.org>

Signed-off-by: Or Gerlitz <ogerlitz-VPRAkNaXOzVWk0Htik3J/w@public.gmane.org>
---
net/rds/ib.c | 34 +++++++++++-----------------------
net/rds/iw.c | 23 +++++------------------
2 files changed, 16 insertions(+), 41 deletions(-)

diff --git a/net/rds/ib.c b/net/rds/ib.c
index f222885..9481d55 100644
--- a/net/rds/ib.c
+++ b/net/rds/ib.c
@@ -122,44 +122,34 @@ void rds_ib_dev_put(struct rds_ib_device *rds_ibdev)
static void rds_ib_add_one(struct ib_device *device)
{
struct rds_ib_device *rds_ibdev;
- struct ib_device_attr *dev_attr;

/* Only handle IB (no iWARP) devices */
if (device->node_type != RDMA_NODE_IB_CA)
return;

- dev_attr = kmalloc(sizeof *dev_attr, GFP_KERNEL);
- if (!dev_attr)
- return;
-
- if (ib_query_device(device, dev_attr)) {
- rdsdebug("Query device failed for %s\n", device->name);
- goto free_attr;
- }
-
rds_ibdev = kzalloc_node(sizeof(struct rds_ib_device), GFP_KERNEL,
ibdev_to_node(device));
if (!rds_ibdev)
- goto free_attr;
+ return;

spin_lock_init(&rds_ibdev->spinlock);
atomic_set(&rds_ibdev->refcount, 1);
INIT_WORK(&rds_ibdev->free_work, rds_ib_dev_free);

- rds_ibdev->max_wrs = dev_attr->max_qp_wr;
- rds_ibdev->max_sge = min(dev_attr->max_sge, RDS_IB_MAX_SGE);
+ rds_ibdev->max_wrs = device->attrs.max_qp_wr;
+ rds_ibdev->max_sge = min(device->attrs.max_sge, RDS_IB_MAX_SGE);

- rds_ibdev->fmr_max_remaps = dev_attr->max_map_per_fmr?: 32;
- rds_ibdev->max_1m_fmrs = dev_attr->max_mr ?
- min_t(unsigned int, (dev_attr->max_mr / 2),
+ rds_ibdev->fmr_max_remaps = device->attrs.max_map_per_fmr?: 32;
+ rds_ibdev->max_1m_fmrs = device->attrs.max_mr ?
+ min_t(unsigned int, (device->attrs.max_mr / 2),
rds_ib_fmr_1m_pool_size) : rds_ib_fmr_1m_pool_size;

- rds_ibdev->max_8k_fmrs = dev_attr->max_mr ?
- min_t(unsigned int, ((dev_attr->max_mr / 2) * RDS_MR_8K_SCALE),
+ rds_ibdev->max_8k_fmrs = device->attrs.max_mr ?
+ min_t(unsigned int, ((device->attrs.max_mr / 2) * RDS_MR_8K_SCALE),
rds_ib_fmr_8k_pool_size) : rds_ib_fmr_8k_pool_size;

- rds_ibdev->max_initiator_depth = dev_attr->max_qp_init_rd_atom;
- rds_ibdev->max_responder_resources = dev_attr->max_qp_rd_atom;
+ rds_ibdev->max_initiator_depth = device->attrs.max_qp_init_rd_atom;
+ rds_ibdev->max_responder_resources = device->attrs.max_qp_rd_atom;

rds_ibdev->dev = device;
rds_ibdev->pd = ib_alloc_pd(device);
@@ -183,7 +173,7 @@ static void rds_ib_add_one(struct ib_device *device)
}

rdsdebug("RDS/IB: max_mr = %d, max_wrs = %d, max_sge = %d, fmr_max_remaps = %d, max_1m_fmrs = %d, max_8k_fmrs = %d\n",
- dev_attr->max_fmr, rds_ibdev->max_wrs, rds_ibdev->max_sge,
+ device->attrs.max_fmr, rds_ibdev->max_wrs, rds_ibdev->max_sge,
rds_ibdev->fmr_max_remaps, rds_ibdev->max_1m_fmrs,
rds_ibdev->max_8k_fmrs);

@@ -202,8 +192,6 @@ static void rds_ib_add_one(struct ib_device *device)

put_dev:
rds_ib_dev_put(rds_ibdev);
-free_attr:
- kfree(dev_attr);
}

/*
diff --git a/net/rds/iw.c b/net/rds/iw.c
index 576f182..f4a9fff 100644
--- a/net/rds/iw.c
+++ b/net/rds/iw.c
@@ -60,30 +60,20 @@ LIST_HEAD(iw_nodev_conns);
static void rds_iw_add_one(struct ib_device *device)
{
struct rds_iw_device *rds_iwdev;
- struct ib_device_attr *dev_attr;

/* Only handle iwarp devices */
if (device->node_type != RDMA_NODE_RNIC)
return;

- dev_attr = kmalloc(sizeof *dev_attr, GFP_KERNEL);
- if (!dev_attr)
- return;
-
- if (ib_query_device(device, dev_attr)) {
- rdsdebug("Query device failed for %s\n", device->name);
- goto free_attr;
- }
-
rds_iwdev = kmalloc(sizeof *rds_iwdev, GFP_KERNEL);
if (!rds_iwdev)
- goto free_attr;
+ return;

spin_lock_init(&rds_iwdev->spinlock);

- rds_iwdev->dma_local_lkey = !!(dev_attr->device_cap_flags & IB_DEVICE_LOCAL_DMA_LKEY);
- rds_iwdev->max_wrs = dev_attr->max_qp_wr;
- rds_iwdev->max_sge = min(dev_attr->max_sge, RDS_IW_MAX_SGE);
+ rds_iwdev->dma_local_lkey = !!(device->attrs.device_cap_flags & IB_DEVICE_LOCAL_DMA_LKEY);
+ rds_iwdev->max_wrs = device->attrs.max_qp_wr;
+ rds_iwdev->max_sge = min(device->attrs.max_sge, RDS_IW_MAX_SGE);

rds_iwdev->dev = device;
rds_iwdev->pd = ib_alloc_pd(device);
@@ -111,8 +101,7 @@ static void rds_iw_add_one(struct ib_device *device)
list_add_tail(&rds_iwdev->list, &rds_iw_devices);

ib_set_client_data(device, &rds_iw_client, rds_iwdev);
-
- goto free_attr;
+ return;

err_mr:
if (rds_iwdev->mr)
@@ -121,8 +110,6 @@ err_pd:
ib_dealloc_pd(rds_iwdev->pd);
free_dev:
kfree(rds_iwdev);
-free_attr:
- kfree(dev_attr);
}

static void rds_iw_remove_one(struct ib_device *device, void *client_data)
--
2.3.7