The ice_write_rxq_ctx() function is responsible for programming the Rx Queue context into hardware. It receives the configuration in unpacked form via the ice_rlan_ctx structure.
This function unconditionally modifies the context to set the prefetch enable bit. This was done by commit c31a5c25bb19 ("ice: Always set prefena when configuring an Rx queue"). Setting this bit makes sense, since prefetching descriptors is almost always the preferred behavior. However, the ice_write_rxq_ctx() function is not the place that actually defines the queue context. We initialize the Rx Queue context in ice_setup_rx_ctx(). It is surprising to have the Rx queue context changed by a function who's responsibility is to program the given context to hardware. Following the principle of least surprise, move the setting of the prefetch enable bit out of ice_write_rxq_ctx() and into the ice_setup_rx_ctx(). Fixes: c31a5c25bb19 ("ice: Always set prefena when configuring an Rx queue") Signed-off-by: Jacob Keller <jacob.e.kel...@intel.com> --- drivers/net/ethernet/intel/ice/ice_base.c | 3 +++ drivers/net/ethernet/intel/ice/ice_common.c | 9 +++------ 2 files changed, 6 insertions(+), 6 deletions(-) diff --git a/drivers/net/ethernet/intel/ice/ice_base.c b/drivers/net/ethernet/intel/ice/ice_base.c index 1881ce8105ca..3fe87a30c29e 100644 --- a/drivers/net/ethernet/intel/ice/ice_base.c +++ b/drivers/net/ethernet/intel/ice/ice_base.c @@ -453,6 +453,9 @@ static int ice_setup_rx_ctx(struct ice_rx_ring *ring) /* Rx queue threshold in units of 64 */ rlan_ctx.lrxqthresh = 1; + /* Enable descriptor prefetch */ + rlan_ctx.prefena = 1; + /* PF acts as uplink for switchdev; set flex descriptor with src_vsi * metadata and flags to allow redirecting to PR netdev */ diff --git a/drivers/net/ethernet/intel/ice/ice_common.c b/drivers/net/ethernet/intel/ice/ice_common.c index 09a94c20e16d..67273e4af7ff 100644 --- a/drivers/net/ethernet/intel/ice/ice_common.c +++ b/drivers/net/ethernet/intel/ice/ice_common.c @@ -1495,14 +1495,13 @@ const struct ice_ctx_ele ice_rlan_ctx_info[] = { }; /** - * ice_write_rxq_ctx + * ice_write_rxq_ctx - Write Rx Queue context to hardware * @hw: pointer to the hardware structure * @rlan_ctx: pointer to the rxq context * @rxq_index: the index of the Rx queue * - * Converts rxq context from sparse to dense structure and then writes - * it to HW register space and enables the hardware to prefetch descriptors - * instead of only fetching them on demand + * Pack the sparse Rx Queue context into dense hardware format and write it + * into the HW register space. */ int ice_write_rxq_ctx(struct ice_hw *hw, struct ice_rlan_ctx *rlan_ctx, u32 rxq_index) @@ -1512,8 +1511,6 @@ int ice_write_rxq_ctx(struct ice_hw *hw, struct ice_rlan_ctx *rlan_ctx, if (!rlan_ctx) return -EINVAL; - rlan_ctx->prefena = 1; - ice_pack_rxq_ctx(rlan_ctx, ctx_buf); return ice_copy_rxq_ctx_to_hw(hw, ctx_buf, rxq_index); -- 2.46.0.124.g2dc1a81c8933