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path: root/drivers/net/ethernet/intel/i40e/i40e_txrx.c
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Diffstat (limited to 'drivers/net/ethernet/intel/i40e/i40e_txrx.c')
-rw-r--r--drivers/net/ethernet/intel/i40e/i40e_txrx.c214
1 files changed, 87 insertions, 127 deletions
diff --git a/drivers/net/ethernet/intel/i40e/i40e_txrx.c b/drivers/net/ethernet/intel/i40e/i40e_txrx.c
index 738aca68f665..3ce4900c0c43 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_txrx.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_txrx.c
@@ -601,27 +601,13 @@ void i40e_free_tx_resources(struct i40e_ring *tx_ring)
}
/**
- * i40e_get_head - Retrieve head from head writeback
- * @tx_ring: tx ring to fetch head of
- *
- * Returns value of Tx ring head based on value stored
- * in head write-back location
- **/
-static inline u32 i40e_get_head(struct i40e_ring *tx_ring)
-{
- void *head = (struct i40e_tx_desc *)tx_ring->desc + tx_ring->count;
-
- return le32_to_cpu(*(volatile __le32 *)head);
-}
-
-/**
* i40e_get_tx_pending - how many tx descriptors not processed
* @tx_ring: the ring of descriptors
*
* Since there is no access to the ring head register
* in XL710, we need to use our local copies
**/
-static u32 i40e_get_tx_pending(struct i40e_ring *ring)
+u32 i40e_get_tx_pending(struct i40e_ring *ring)
{
u32 head, tail;
@@ -635,50 +621,6 @@ static u32 i40e_get_tx_pending(struct i40e_ring *ring)
return 0;
}
-/**
- * i40e_check_tx_hang - Is there a hang in the Tx queue
- * @tx_ring: the ring of descriptors
- **/
-static bool i40e_check_tx_hang(struct i40e_ring *tx_ring)
-{
- u32 tx_done = tx_ring->stats.packets;
- u32 tx_done_old = tx_ring->tx_stats.tx_done_old;
- u32 tx_pending = i40e_get_tx_pending(tx_ring);
- struct i40e_pf *pf = tx_ring->vsi->back;
- bool ret = false;
-
- clear_check_for_tx_hang(tx_ring);
-
- /* Check for a hung queue, but be thorough. This verifies
- * that a transmit has been completed since the previous
- * check AND there is at least one packet pending. The
- * ARMED bit is set to indicate a potential hang. The
- * bit is cleared if a pause frame is received to remove
- * false hang detection due to PFC or 802.3x frames. By
- * requiring this to fail twice we avoid races with
- * PFC clearing the ARMED bit and conditions where we
- * run the check_tx_hang logic with a transmit completion
- * pending but without time to complete it yet.
- */
- if ((tx_done_old == tx_done) && tx_pending) {
- /* make sure it is true for two checks in a row */
- ret = test_and_set_bit(__I40E_HANG_CHECK_ARMED,
- &tx_ring->state);
- } else if (tx_done_old == tx_done &&
- (tx_pending < I40E_MIN_DESC_PENDING) && (tx_pending > 0)) {
- if (I40E_DEBUG_FLOW & pf->hw.debug_mask)
- dev_info(tx_ring->dev, "HW needs some more descs to do a cacheline flush. tx_pending %d, queue %d",
- tx_pending, tx_ring->queue_index);
- pf->tx_sluggish_count++;
- } else {
- /* update completed stats and disarm the hang check */
- tx_ring->tx_stats.tx_done_old = tx_done;
- clear_bit(__I40E_HANG_CHECK_ARMED, &tx_ring->state);
- }
-
- return ret;
-}
-
#define WB_STRIDE 0x3
/**
@@ -784,42 +726,21 @@ static bool i40e_clean_tx_irq(struct i40e_ring *tx_ring, int budget)
tx_ring->q_vector->tx.total_bytes += total_bytes;
tx_ring->q_vector->tx.total_packets += total_packets;
- /* check to see if there are any non-cache aligned descriptors
- * waiting to be written back, and kick the hardware to force
- * them to be written back in case of napi polling
- */
- if (budget &&
- !((i & WB_STRIDE) == WB_STRIDE) &&
- !test_bit(__I40E_DOWN, &tx_ring->vsi->state) &&
- (I40E_DESC_UNUSED(tx_ring) != tx_ring->count))
- tx_ring->arm_wb = true;
- else
- tx_ring->arm_wb = false;
-
- if (check_for_tx_hang(tx_ring) && i40e_check_tx_hang(tx_ring)) {
- /* schedule immediate reset if we believe we hung */
- dev_info(tx_ring->dev, "Detected Tx Unit Hang\n"
- " VSI <%d>\n"
- " Tx Queue <%d>\n"
- " next_to_use <%x>\n"
- " next_to_clean <%x>\n",
- tx_ring->vsi->seid,
- tx_ring->queue_index,
- tx_ring->next_to_use, i);
-
- netif_stop_subqueue(tx_ring->netdev, tx_ring->queue_index);
-
- dev_info(tx_ring->dev,
- "tx hang detected on queue %d, reset requested\n",
- tx_ring->queue_index);
-
- /* do not fire the reset immediately, wait for the stack to
- * decide we are truly stuck, also prevents every queue from
- * simultaneously requesting a reset
+ if (tx_ring->flags & I40E_TXR_FLAGS_WB_ON_ITR) {
+ unsigned int j = 0;
+
+ /* check to see if there are < 4 descriptors
+ * waiting to be written back, then kick the hardware to force
+ * them to be written back in case we stay in NAPI.
+ * In this mode on X722 we do not enable Interrupt.
*/
+ j = i40e_get_tx_pending(tx_ring);
- /* the adapter is about to reset, no point in enabling polling */
- budget = 1;
+ if (budget &&
+ ((j / (WB_STRIDE + 1)) == 0) && (j != 0) &&
+ !test_bit(__I40E_DOWN, &tx_ring->vsi->state) &&
+ (I40E_DESC_UNUSED(tx_ring) != tx_ring->count))
+ tx_ring->arm_wb = true;
}
netdev_tx_completed_queue(netdev_get_tx_queue(tx_ring->netdev,
@@ -851,7 +772,7 @@ static bool i40e_clean_tx_irq(struct i40e_ring *tx_ring, int budget)
* @q_vector: the vector on which to force writeback
*
**/
-static void i40e_force_wb(struct i40e_vsi *vsi, struct i40e_q_vector *q_vector)
+void i40e_force_wb(struct i40e_vsi *vsi, struct i40e_q_vector *q_vector)
{
u16 flags = q_vector->tx.ring[0].flags;
@@ -2324,6 +2245,9 @@ static void i40e_tx_enable_csum(struct sk_buff *skb, u32 *tx_flags,
l4_tunnel = I40E_TXD_CTX_UDP_TUNNELING;
*tx_flags |= I40E_TX_FLAGS_VXLAN_TUNNEL;
break;
+ case IPPROTO_GRE:
+ l4_tunnel = I40E_TXD_CTX_GRE_TUNNELING;
+ break;
default:
return;
}
@@ -2581,6 +2505,9 @@ static inline void i40e_tx_map(struct i40e_ring *tx_ring, struct sk_buff *skb,
u32 td_tag = 0;
dma_addr_t dma;
u16 gso_segs;
+ u16 desc_count = 0;
+ bool tail_bump = true;
+ bool do_rs = false;
if (tx_flags & I40E_TX_FLAGS_HW_VLAN) {
td_cmd |= I40E_TX_DESC_CMD_IL2TAG1;
@@ -2621,6 +2548,8 @@ static inline void i40e_tx_map(struct i40e_ring *tx_ring, struct sk_buff *skb,
tx_desc++;
i++;
+ desc_count++;
+
if (i == tx_ring->count) {
tx_desc = I40E_TX_DESC(tx_ring, 0);
i = 0;
@@ -2640,6 +2569,8 @@ static inline void i40e_tx_map(struct i40e_ring *tx_ring, struct sk_buff *skb,
tx_desc++;
i++;
+ desc_count++;
+
if (i == tx_ring->count) {
tx_desc = I40E_TX_DESC(tx_ring, 0);
i = 0;
@@ -2654,34 +2585,6 @@ static inline void i40e_tx_map(struct i40e_ring *tx_ring, struct sk_buff *skb,
tx_bi = &tx_ring->tx_bi[i];
}
- /* Place RS bit on last descriptor of any packet that spans across the
- * 4th descriptor (WB_STRIDE aka 0x3) in a 64B cacheline.
- */
- if (((i & WB_STRIDE) != WB_STRIDE) &&
- (first <= &tx_ring->tx_bi[i]) &&
- (first >= &tx_ring->tx_bi[i & ~WB_STRIDE])) {
- tx_desc->cmd_type_offset_bsz =
- build_ctob(td_cmd, td_offset, size, td_tag) |
- cpu_to_le64((u64)I40E_TX_DESC_CMD_EOP <<
- I40E_TXD_QW1_CMD_SHIFT);
- } else {
- tx_desc->cmd_type_offset_bsz =
- build_ctob(td_cmd, td_offset, size, td_tag) |
- cpu_to_le64((u64)I40E_TXD_CMD <<
- I40E_TXD_QW1_CMD_SHIFT);
- }
-
- netdev_tx_sent_queue(netdev_get_tx_queue(tx_ring->netdev,
- tx_ring->queue_index),
- first->bytecount);
-
- /* Force memory writes to complete before letting h/w
- * know there are new descriptors to fetch. (Only
- * applicable for weak-ordered memory model archs,
- * such as IA-64).
- */
- wmb();
-
/* set next_to_watch value indicating a packet is present */
first->next_to_watch = tx_desc;
@@ -2691,15 +2594,72 @@ static inline void i40e_tx_map(struct i40e_ring *tx_ring, struct sk_buff *skb,
tx_ring->next_to_use = i;
+ netdev_tx_sent_queue(netdev_get_tx_queue(tx_ring->netdev,
+ tx_ring->queue_index),
+ first->bytecount);
i40e_maybe_stop_tx(tx_ring, DESC_NEEDED);
+
+ /* Algorithm to optimize tail and RS bit setting:
+ * if xmit_more is supported
+ * if xmit_more is true
+ * do not update tail and do not mark RS bit.
+ * if xmit_more is false and last xmit_more was false
+ * if every packet spanned less than 4 desc
+ * then set RS bit on 4th packet and update tail
+ * on every packet
+ * else
+ * update tail and set RS bit on every packet.
+ * if xmit_more is false and last_xmit_more was true
+ * update tail and set RS bit.
+ *
+ * Optimization: wmb to be issued only in case of tail update.
+ * Also optimize the Descriptor WB path for RS bit with the same
+ * algorithm.
+ *
+ * Note: If there are less than 4 packets
+ * pending and interrupts were disabled the service task will
+ * trigger a force WB.
+ */
+ if (skb->xmit_more &&
+ !netif_xmit_stopped(netdev_get_tx_queue(tx_ring->netdev,
+ tx_ring->queue_index))) {
+ tx_ring->flags |= I40E_TXR_FLAGS_LAST_XMIT_MORE_SET;
+ tail_bump = false;
+ } else if (!skb->xmit_more &&
+ !netif_xmit_stopped(netdev_get_tx_queue(tx_ring->netdev,
+ tx_ring->queue_index)) &&
+ (!(tx_ring->flags & I40E_TXR_FLAGS_LAST_XMIT_MORE_SET)) &&
+ (tx_ring->packet_stride < WB_STRIDE) &&
+ (desc_count < WB_STRIDE)) {
+ tx_ring->packet_stride++;
+ } else {
+ tx_ring->packet_stride = 0;
+ tx_ring->flags &= ~I40E_TXR_FLAGS_LAST_XMIT_MORE_SET;
+ do_rs = true;
+ }
+ if (do_rs)
+ tx_ring->packet_stride = 0;
+
+ tx_desc->cmd_type_offset_bsz =
+ build_ctob(td_cmd, td_offset, size, td_tag) |
+ cpu_to_le64((u64)(do_rs ? I40E_TXD_CMD :
+ I40E_TX_DESC_CMD_EOP) <<
+ I40E_TXD_QW1_CMD_SHIFT);
+
/* notify HW of packet */
- if (!skb->xmit_more ||
- netif_xmit_stopped(netdev_get_tx_queue(tx_ring->netdev,
- tx_ring->queue_index)))
- writel(i, tx_ring->tail);
- else
+ if (!tail_bump)
prefetchw(tx_desc + 1);
+ if (tail_bump) {
+ /* Force memory writes to complete before letting h/w
+ * know there are new descriptors to fetch. (Only
+ * applicable for weak-ordered memory model archs,
+ * such as IA-64).
+ */
+ wmb();
+ writel(i, tx_ring->tail);
+ }
+
return;
dma_error:
generated by cgit v1.2.3 (git 2.46.0) at 2025-09-01 23:29:59 +0000