@@ -524,6 +524,11 @@ struct ena_admin_feature_llq_desc {
/* the stride control the driver selected to use */
u16 descriptors_stride_ctrl_enabled;
+
+ /* Maximum size in bytes taken by llq entries in a single tx burst.
+ * Set to 0 when there is no such limit.
+ */
+ u32 max_tx_burst_size;
};
struct ena_admin_queue_feature_desc {
@@ -396,6 +396,10 @@ static int ena_com_init_io_sq(struct ena_com_dev *ena_dev,
0x0, io_sq->llq_info.desc_list_entry_size);
io_sq->llq_buf_ctrl.descs_left_in_line =
io_sq->llq_info.descs_num_before_header;
+
+ if (io_sq->llq_info.max_entries_in_tx_burst > 0)
+ io_sq->entries_in_tx_burst_left =
+ io_sq->llq_info.max_entries_in_tx_burst;
}
io_sq->tail = 0;
@@ -727,6 +731,9 @@ static int ena_com_config_llq_info(struct ena_com_dev *ena_dev,
supported_feat, llq_info->descs_num_before_header);
}
+ llq_info->max_entries_in_tx_burst =
+ (u16)(llq_features->max_tx_burst_size / llq_default_cfg->llq_ring_entry_size_value);
+
rc = ena_com_set_llq(ena_dev);
if (rc)
pr_err("Cannot set LLQ configuration: %d\n", rc);
@@ -159,6 +159,7 @@ struct ena_com_llq_info {
u16 desc_list_entry_size;
u16 descs_num_before_header;
u16 descs_per_entry;
+ u16 max_entries_in_tx_burst;
};
struct ena_com_io_cq {
@@ -238,6 +239,7 @@ struct ena_com_io_sq {
u8 phase;
u8 desc_entry_size;
u8 dma_addr_bits;
+ u16 entries_in_tx_burst_left;
} ____cacheline_aligned;
struct ena_com_admin_cq {
@@ -82,6 +82,17 @@ static inline int ena_com_write_bounce_buffer_to_dev(struct ena_com_io_sq *io_sq
dst_tail_mask = io_sq->tail & (io_sq->q_depth - 1);
dst_offset = dst_tail_mask * llq_info->desc_list_entry_size;
+ if (is_llq_max_tx_burst_exists(io_sq)) {
+ if (unlikely(!io_sq->entries_in_tx_burst_left)) {
+ pr_err("Error: trying to send more packets than tx burst allows\n");
+ return -ENOSPC;
+ }
+
+ io_sq->entries_in_tx_burst_left--;
+ pr_debug("decreasing entries_in_tx_burst_left of queue %d to %d\n",
+ io_sq->qid, io_sq->entries_in_tx_burst_left);
+ }
+
/* Make sure everything was written into the bounce buffer before
* writing the bounce buffer to the device
*/
@@ -274,23 +285,6 @@ static inline u16 ena_com_cdesc_rx_pkt_get(struct ena_com_io_cq *io_cq,
return count;
}
-static inline bool ena_com_meta_desc_changed(struct ena_com_io_sq *io_sq,
- struct ena_com_tx_ctx *ena_tx_ctx)
-{
- int rc;
-
- if (ena_tx_ctx->meta_valid) {
- rc = memcmp(&io_sq->cached_tx_meta,
- &ena_tx_ctx->ena_meta,
- sizeof(struct ena_com_tx_meta));
-
- if (unlikely(rc != 0))
- return true;
- }
-
- return false;
-}
-
static inline int ena_com_create_and_store_tx_meta_desc(struct ena_com_io_sq *io_sq,
struct ena_com_tx_ctx *ena_tx_ctx)
{
@@ -125,8 +125,55 @@ static inline bool ena_com_sq_have_enough_space(struct ena_com_io_sq *io_sq,
return ena_com_free_desc(io_sq) > temp;
}
+static inline bool ena_com_meta_desc_changed(struct ena_com_io_sq *io_sq,
+ struct ena_com_tx_ctx *ena_tx_ctx)
+{
+ if (!ena_tx_ctx->meta_valid)
+ return false;
+
+ return !!memcmp(&io_sq->cached_tx_meta,
+ &ena_tx_ctx->ena_meta,
+ sizeof(struct ena_com_tx_meta));
+}
+
+static inline bool is_llq_max_tx_burst_exists(struct ena_com_io_sq *io_sq)
+{
+ return (io_sq->mem_queue_type == ENA_ADMIN_PLACEMENT_POLICY_DEV) &&
+ io_sq->llq_info.max_entries_in_tx_burst > 0;
+}
+
+static inline bool ena_com_is_doorbell_needed(struct ena_com_io_sq *io_sq,
+ struct ena_com_tx_ctx *ena_tx_ctx)
+{
+ struct ena_com_llq_info *llq_info;
+ int descs_after_first_entry;
+ int num_entries_needed = 1;
+ u16 num_descs;
+
+ if (!is_llq_max_tx_burst_exists(io_sq))
+ return false;
+
+ llq_info = &io_sq->llq_info;
+ num_descs = ena_tx_ctx->num_bufs;
+
+ if (unlikely(ena_com_meta_desc_changed(io_sq, ena_tx_ctx)))
+ ++num_descs;
+
+ if (num_descs > llq_info->descs_num_before_header) {
+ descs_after_first_entry = num_descs - llq_info->descs_num_before_header;
+ num_entries_needed += DIV_ROUND_UP(descs_after_first_entry,
+ llq_info->descs_per_entry);
+ }
+
+ pr_debug("queue: %d num_descs: %d num_entries_needed: %d\n", io_sq->qid,
+ num_descs, num_entries_needed);
+
+ return num_entries_needed > io_sq->entries_in_tx_burst_left;
+}
+
static inline int ena_com_write_sq_doorbell(struct ena_com_io_sq *io_sq)
{
+ u16 max_entries_in_tx_burst = io_sq->llq_info.max_entries_in_tx_burst;
u16 tail = io_sq->tail;
pr_debug("write submission queue doorbell for queue: %d tail: %d\n",
@@ -134,6 +181,12 @@ static inline int ena_com_write_sq_doorbell(struct ena_com_io_sq *io_sq)
writel(tail, io_sq->db_addr);
+ if (is_llq_max_tx_burst_exists(io_sq)) {
+ pr_debug("reset available entries in tx burst for queue %d to %d\n",
+ io_sq->qid, max_entries_in_tx_burst);
+ io_sq->entries_in_tx_burst_left = max_entries_in_tx_burst;
+ }
+
return 0;
}
@@ -2172,6 +2172,13 @@ static netdev_tx_t ena_start_xmit(struct sk_buff *skb, struct net_device *dev)
/* set flags and meta data */
ena_tx_csum(&ena_tx_ctx, skb);
+ if (unlikely(ena_com_is_doorbell_needed(tx_ring->ena_com_io_sq, &ena_tx_ctx))) {
+ netif_dbg(adapter, tx_queued, dev,
+ "llq tx max burst size of queue %d achieved, writing doorbell to send burst\n",
+ qid);
+ ena_com_write_sq_doorbell(tx_ring->ena_com_io_sq);
+ }
+
/* prepare the packet's descriptors to dma engine */
rc = ena_com_prepare_tx(tx_ring->ena_com_io_sq, &ena_tx_ctx,
&nb_hw_desc);