This patch optimize current implementation as follow: - Drop the leading barrier which affects non X86 ARCH(s) till making further optimization to prevent performance degradation. - In ARCH(s) that spinlock() serves also as SFENCE prevent an another explicit SFENCE. (e.g. X86). Signed-off-by: Yishai Hadas <yishaih@xxxxxxxxxxxx> --- providers/mlx4/qp.c | 19 +++++++------------ 1 file changed, 7 insertions(+), 12 deletions(-) diff --git a/providers/mlx4/qp.c b/providers/mlx4/qp.c index e9a59f9..a8eb8e2 100644 --- a/providers/mlx4/qp.c +++ b/providers/mlx4/qp.c @@ -203,7 +203,7 @@ static void set_data_seg(struct mlx4_wqe_data_seg *dseg, struct ibv_sge *sg) * chunk and get a valid (!= * 0xffffffff) byte count but * stale data, and end up sending the wrong data. */ - udma_ordering_write_barrier(); + udma_to_device_barrier(); if (likely(sg->length)) dseg->byte_count = htobe32(sg->length); @@ -227,9 +227,6 @@ int mlx4_post_send(struct ibv_qp *ibqp, struct ibv_send_wr *wr, pthread_spin_lock(&qp->sq.lock); - /* Get all user DMA buffers ready to go */ - udma_to_device_barrier(); - /* XXX check that state is OK to post send */ ind = qp->sq.head; @@ -402,7 +399,7 @@ int mlx4_post_send(struct ibv_qp *ibqp, struct ibv_send_wr *wr, wqe += to_copy; addr += to_copy; seg_len += to_copy; - udma_ordering_write_barrier(); /* see comment below */ + udma_to_device_barrier(); /* see comment below */ seg->byte_count = htobe32(MLX4_INLINE_SEG | seg_len); seg_len = 0; seg = wqe; @@ -430,7 +427,7 @@ int mlx4_post_send(struct ibv_qp *ibqp, struct ibv_send_wr *wr, * data, and end up sending the wrong * data. */ - udma_ordering_write_barrier(); + udma_to_device_barrier(); seg->byte_count = htobe32(MLX4_INLINE_SEG | seg_len); } @@ -452,7 +449,7 @@ int mlx4_post_send(struct ibv_qp *ibqp, struct ibv_send_wr *wr, * setting ownership bit (because HW can start * executing as soon as we do). */ - udma_ordering_write_barrier(); + udma_to_device_barrier(); ctrl->owner_opcode = htobe32(mlx4_ib_opcode[wr->opcode]) | (ind & qp->sq.wqe_cnt ? htobe32(1 << 31) : 0); @@ -476,18 +473,16 @@ out: ctrl->owner_opcode |= htobe32((qp->sq.head & 0xffff) << 8); ctrl->bf_qpn |= qp->doorbell_qpn; + ++qp->sq.head; /* * Make sure that descriptor is written to memory * before writing to BlueFlame page. */ - mmio_wc_start(); - - ++qp->sq.head; - - pthread_spin_lock(&ctx->bf_lock); + mmio_wc_spinlock(&ctx->bf_lock); mlx4_bf_copy(ctx->bf_page + ctx->bf_offset, (unsigned long *) ctrl, align(size * 16, 64)); + /* Flush before toggling bf_offset to be latency oriented */ mmio_flush_writes(); ctx->bf_offset ^= ctx->bf_buf_size; -- 1.8.3.1 -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
