IB/mlx4: Remove limitation on LSO header size

Current code has a limitation: an LSO header is not allowed to cross a
64 byte boundary.  This patch removes this limitation by setting the
WQE RR for large headers thus allowing LSO headers of any size.  The
extra buffer reserved for MLX4_IB_QP_LSO QPs has been doubled, from 64
to 128 bytes, assuming this is reasonable upper limit for header
length.  Also, this patch will cause IB_DEVICE_UD_TSO to be set only
for HCA FW versions that set MLX4_DEV_CAP_FLAG_BLH; e.g. FW version
2.6.000 and higher.

Signed-off-by: Eli Cohen <eli@mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
This commit is contained in:
Eli Cohen 2009-11-12 11:19:44 -08:00 committed by Roland Dreier
parent ecdc428e4c
commit 417608c20a
4 changed files with 15 additions and 13 deletions

View file

@ -103,7 +103,7 @@ static int mlx4_ib_query_device(struct ib_device *ibdev,
props->device_cap_flags |= IB_DEVICE_UD_AV_PORT_ENFORCE;
if (dev->dev->caps.flags & MLX4_DEV_CAP_FLAG_IPOIB_CSUM)
props->device_cap_flags |= IB_DEVICE_UD_IP_CSUM;
if (dev->dev->caps.max_gso_sz)
if (dev->dev->caps.max_gso_sz && dev->dev->caps.flags & MLX4_DEV_CAP_FLAG_BLH)
props->device_cap_flags |= IB_DEVICE_UD_TSO;
if (dev->dev->caps.bmme_flags & MLX4_BMME_FLAG_RESERVED_LKEY)
props->device_cap_flags |= IB_DEVICE_LOCAL_DMA_LKEY;

View file

@ -54,7 +54,8 @@ enum {
/*
* Largest possible UD header: send with GRH and immediate data.
*/
MLX4_IB_UD_HEADER_SIZE = 72
MLX4_IB_UD_HEADER_SIZE = 72,
MLX4_IB_LSO_HEADER_SPARE = 128,
};
struct mlx4_ib_sqp {
@ -67,7 +68,8 @@ struct mlx4_ib_sqp {
};
enum {
MLX4_IB_MIN_SQ_STRIDE = 6
MLX4_IB_MIN_SQ_STRIDE = 6,
MLX4_IB_CACHE_LINE_SIZE = 64,
};
static const __be32 mlx4_ib_opcode[] = {
@ -261,7 +263,7 @@ static int send_wqe_overhead(enum ib_qp_type type, u32 flags)
case IB_QPT_UD:
return sizeof (struct mlx4_wqe_ctrl_seg) +
sizeof (struct mlx4_wqe_datagram_seg) +
((flags & MLX4_IB_QP_LSO) ? 64 : 0);
((flags & MLX4_IB_QP_LSO) ? MLX4_IB_LSO_HEADER_SPARE : 0);
case IB_QPT_UC:
return sizeof (struct mlx4_wqe_ctrl_seg) +
sizeof (struct mlx4_wqe_raddr_seg);
@ -1466,16 +1468,12 @@ static void __set_data_seg(struct mlx4_wqe_data_seg *dseg, struct ib_sge *sg)
static int build_lso_seg(struct mlx4_wqe_lso_seg *wqe, struct ib_send_wr *wr,
struct mlx4_ib_qp *qp, unsigned *lso_seg_len,
__be32 *lso_hdr_sz)
__be32 *lso_hdr_sz, __be32 *blh)
{
unsigned halign = ALIGN(sizeof *wqe + wr->wr.ud.hlen, 16);
/*
* This is a temporary limitation and will be removed in
* a forthcoming FW release:
*/
if (unlikely(halign > 64))
return -EINVAL;
if (unlikely(halign > MLX4_IB_CACHE_LINE_SIZE))
*blh = cpu_to_be32(1 << 6);
if (unlikely(!(qp->flags & MLX4_IB_QP_LSO) &&
wr->num_sge > qp->sq.max_gs - (halign >> 4)))
@ -1521,6 +1519,7 @@ int mlx4_ib_post_send(struct ib_qp *ibqp, struct ib_send_wr *wr,
__be32 dummy;
__be32 *lso_wqe;
__be32 uninitialized_var(lso_hdr_sz);
__be32 blh;
int i;
spin_lock_irqsave(&qp->sq.lock, flags);
@ -1529,6 +1528,7 @@ int mlx4_ib_post_send(struct ib_qp *ibqp, struct ib_send_wr *wr,
for (nreq = 0; wr; ++nreq, wr = wr->next) {
lso_wqe = &dummy;
blh = 0;
if (mlx4_wq_overflow(&qp->sq, nreq, qp->ibqp.send_cq)) {
err = -ENOMEM;
@ -1615,7 +1615,7 @@ int mlx4_ib_post_send(struct ib_qp *ibqp, struct ib_send_wr *wr,
size += sizeof (struct mlx4_wqe_datagram_seg) / 16;
if (wr->opcode == IB_WR_LSO) {
err = build_lso_seg(wqe, wr, qp, &seglen, &lso_hdr_sz);
err = build_lso_seg(wqe, wr, qp, &seglen, &lso_hdr_sz, &blh);
if (unlikely(err)) {
*bad_wr = wr;
goto out;
@ -1686,7 +1686,7 @@ int mlx4_ib_post_send(struct ib_qp *ibqp, struct ib_send_wr *wr,
}
ctrl->owner_opcode = mlx4_ib_opcode[wr->opcode] |
(ind & qp->sq.wqe_cnt ? cpu_to_be32(1 << 31) : 0);
(ind & qp->sq.wqe_cnt ? cpu_to_be32(1 << 31) : 0) | blh;
stamp = ind + qp->sq_spare_wqes;
ind += DIV_ROUND_UP(size * 16, 1U << qp->sq.wqe_shift);

View file

@ -90,6 +90,7 @@ static void dump_dev_cap_flags(struct mlx4_dev *dev, u32 flags)
[ 9] = "Q_Key violation counter",
[10] = "VMM",
[12] = "DPDP",
[15] = "Big LSO headers",
[16] = "MW support",
[17] = "APM support",
[18] = "Atomic ops support",

View file

@ -61,6 +61,7 @@ enum {
MLX4_DEV_CAP_FLAG_BAD_PKEY_CNTR = 1 << 8,
MLX4_DEV_CAP_FLAG_BAD_QKEY_CNTR = 1 << 9,
MLX4_DEV_CAP_FLAG_DPDP = 1 << 12,
MLX4_DEV_CAP_FLAG_BLH = 1 << 15,
MLX4_DEV_CAP_FLAG_MEM_WINDOW = 1 << 16,
MLX4_DEV_CAP_FLAG_APM = 1 << 17,
MLX4_DEV_CAP_FLAG_ATOMIC = 1 << 18,