IPoIB internal post and work completion handler changes. Signed-off-by: Krishna Kumar <[EMAIL PROTECTED]> --- ipoib_ib.c | 217 ++++++++++++++++++++++++++++++++++++++++++++++++------------- 1 files changed, 173 insertions(+), 44 deletions(-)
diff -ruNp ORG/drivers/infiniband/ulp/ipoib/ipoib_ib.c NEW/drivers/infiniband/ulp/ipoib/ipoib_ib.c --- ORG/drivers/infiniband/ulp/ipoib/ipoib_ib.c 2007-07-17 08:48:35.000000000 +0530 +++ NEW/drivers/infiniband/ulp/ipoib/ipoib_ib.c 2007-08-07 13:11:19.000000000 +0530 @@ -242,6 +242,8 @@ repost: static void ipoib_ib_handle_tx_wc(struct net_device *dev, struct ib_wc *wc) { struct ipoib_dev_priv *priv = netdev_priv(dev); + int i, num_completions; + unsigned int tx_ring_index; unsigned int wr_id = wc->wr_id; struct ipoib_tx_buf *tx_req; unsigned long flags; @@ -255,18 +257,56 @@ static void ipoib_ib_handle_tx_wc(struct return; } - tx_req = &priv->tx_ring[wr_id]; + /* + * Handle skbs completion from tx_tail to wr_id. Two issues : + * - Need to stop other WC's from mangling same skb's if they + * run at the same time. Use tx_prev_tail to demarcate WC's. + * - Handle WC's from earlier (possibly multiple) post_sends in + * this iteration as we move from tx_prev_tail to wr_id, since + * if the last WR (which is the one which requested completion + * notification) failed to be sent for any of those earlier + * request(s), no completion notification is generated for + * successful WR's of those earlier request(s). + */ + spin_lock_irqsave(&priv->comp_lock, flags); + + /* Get start index */ + tx_ring_index = priv->tx_prev_tail & (ipoib_sendq_size - 1); + + /*Find number of WC's */ + num_completions = wr_id - tx_ring_index + 1; + if (unlikely(num_completions <= 0)) + num_completions += ipoib_sendq_size; + + /* Save new start index for any parallel WC's */ + priv->tx_prev_tail += num_completions; + + spin_unlock_irqrestore(&priv->comp_lock, flags); - ib_dma_unmap_single(priv->ca, tx_req->mapping, - tx_req->skb->len, DMA_TO_DEVICE); + tx_req = &priv->tx_ring[tx_ring_index]; + for (i = 0; i < num_completions; i++) { + if (likely(tx_req->skb)) { + ib_dma_unmap_single(priv->ca, tx_req->mapping, + tx_req->skb->len, DMA_TO_DEVICE); - ++priv->stats.tx_packets; - priv->stats.tx_bytes += tx_req->skb->len; + ++priv->stats.tx_packets; + priv->stats.tx_bytes += tx_req->skb->len; - dev_kfree_skb_any(tx_req->skb); + dev_kfree_skb_any(tx_req->skb); + } + /* + * else this skb failed synchronously when posted and was + * freed immediately. + */ + + if (likely(++tx_ring_index != ipoib_sendq_size)) + tx_req++; + else + tx_req = &priv->tx_ring[0]; + } spin_lock_irqsave(&priv->tx_lock, flags); - ++priv->tx_tail; + priv->tx_tail += num_completions; if (unlikely(test_bit(IPOIB_FLAG_NETIF_STOPPED, &priv->flags)) && priv->tx_head - priv->tx_tail <= ipoib_sendq_size >> 1) { clear_bit(IPOIB_FLAG_NETIF_STOPPED, &priv->flags); @@ -340,29 +380,57 @@ void ipoib_ib_completion(struct ib_cq *c netif_rx_schedule(dev_ptr); } -static inline int post_send(struct ipoib_dev_priv *priv, - unsigned int wr_id, - struct ib_ah *address, u32 qpn, - u64 addr, int len) +/* + * post_send : Post WR(s) to the device. + * + * num_skbs is the number of WR's, first_wr is the first slot in tx_wr[] (or + * tx_sge[]). first_wr is normally zero unless a previous post_send returned + * error and we are trying to post the untried WR's, in which case first_wr + * is the index to the first untried WR. + * + * Break the WR link before posting so that provider knows how many WR's to + * process, and this is set back after the post. + */ +static inline int post_send(struct ipoib_dev_priv *priv, u32 qpn, + int first_wr, int num_skbs, + struct ib_send_wr **bad_wr) { - struct ib_send_wr *bad_wr; + int ret; + struct ib_send_wr *last_wr, *next_wr; + + last_wr = &priv->tx_wr[first_wr + num_skbs - 1]; + + /* Set Completion Notification for last WR */ + last_wr->send_flags = IB_SEND_SIGNALED; - priv->tx_sge.addr = addr; - priv->tx_sge.length = len; + /* Terminate the last WR */ + next_wr = last_wr->next; + last_wr->next = NULL; - priv->tx_wr.wr_id = wr_id; - priv->tx_wr.wr.ud.remote_qpn = qpn; - priv->tx_wr.wr.ud.ah = address; + /* Send all the WR's in one doorbell */ + ret = ib_post_send(priv->qp, &priv->tx_wr[first_wr], bad_wr); - return ib_post_send(priv->qp, &priv->tx_wr, &bad_wr); + /* Restore send_flags & WR chain */ + last_wr->send_flags = 0; + last_wr->next = next_wr; + + return ret; } -void ipoib_send(struct net_device *dev, struct sk_buff *skb, - struct ipoib_ah *address, u32 qpn) +/* + * Map skb & store skb/mapping in tx_ring; and details of the WR in tx_wr + * to pass to the provider. + * + * Returns: + * 1: Error and the skb is freed. + * 0 skb processed successfully. + */ +int ipoib_process_skb(struct net_device *dev, struct sk_buff *skb, + struct ipoib_dev_priv *priv, struct ipoib_ah *address, + u32 qpn, int wr_num) { - struct ipoib_dev_priv *priv = netdev_priv(dev); - struct ipoib_tx_buf *tx_req; u64 addr; + unsigned int tx_ring_index; if (unlikely(skb->len > priv->mcast_mtu + IPOIB_ENCAP_LEN)) { ipoib_warn(priv, "packet len %d (> %d) too long to send, dropping\n", @@ -370,7 +438,7 @@ void ipoib_send(struct net_device *dev, ++priv->stats.tx_dropped; ++priv->stats.tx_errors; ipoib_cm_skb_too_long(dev, skb, priv->mcast_mtu); - return; + return 1; } ipoib_dbg_data(priv, "sending packet, length=%d address=%p qpn=0x%06x\n", @@ -383,35 +451,96 @@ void ipoib_send(struct net_device *dev, * means we have to make sure everything is properly recorded and * our state is consistent before we call post_send(). */ - tx_req = &priv->tx_ring[priv->tx_head & (ipoib_sendq_size - 1)]; - tx_req->skb = skb; - addr = ib_dma_map_single(priv->ca, skb->data, skb->len, - DMA_TO_DEVICE); + addr = ib_dma_map_single(priv->ca, skb->data, skb->len, DMA_TO_DEVICE); if (unlikely(ib_dma_mapping_error(priv->ca, addr))) { ++priv->stats.tx_errors; dev_kfree_skb_any(skb); - return; + return 1; } - tx_req->mapping = addr; - if (unlikely(post_send(priv, priv->tx_head & (ipoib_sendq_size - 1), - address->ah, qpn, addr, skb->len))) { - ipoib_warn(priv, "post_send failed\n"); - ++priv->stats.tx_errors; - ib_dma_unmap_single(priv->ca, addr, skb->len, DMA_TO_DEVICE); - dev_kfree_skb_any(skb); - } else { - dev->trans_start = jiffies; + tx_ring_index = priv->tx_head & (ipoib_sendq_size - 1); + + /* Save till completion handler executes */ + priv->tx_ring[tx_ring_index].skb = skb; + priv->tx_ring[tx_ring_index].mapping = addr; + + /* Set WR values for the provider to use */ + priv->tx_sge[wr_num].addr = addr; + priv->tx_sge[wr_num].length = skb->len; + + priv->tx_wr[wr_num].wr_id = tx_ring_index; + priv->tx_wr[wr_num].wr.ud.remote_qpn = qpn; + priv->tx_wr[wr_num].wr.ud.ah = address->ah; + + priv->tx_head++; + + if (unlikely(priv->tx_head - priv->tx_tail == ipoib_sendq_size)) { + ipoib_dbg(priv, "TX ring full, stopping kernel net queue\n"); + netif_stop_queue(dev); + set_bit(IPOIB_FLAG_NETIF_STOPPED, &priv->flags); + } - address->last_send = priv->tx_head; - ++priv->tx_head; + return 0; +} - if (priv->tx_head - priv->tx_tail == ipoib_sendq_size) { - ipoib_dbg(priv, "TX ring full, stopping kernel net queue\n"); - netif_stop_queue(dev); - set_bit(IPOIB_FLAG_NETIF_STOPPED, &priv->flags); +/* + * Send num_skbs to the device. If an skb is passed to this function, it is + * single, unprocessed skb send case; otherwise it means that all skbs are + * already processed and put on priv->tx_wr,tx_sge,tx_ring, etc. + */ +void ipoib_send(struct net_device *dev, struct sk_buff *skb, + struct ipoib_ah *address, u32 qpn, int num_skbs) +{ + struct ipoib_dev_priv *priv = netdev_priv(dev); + int first_wr = 0; + + if (skb && ipoib_process_skb(dev, skb, priv, address, qpn, 0)) + return; + + /* Send all skb's in one post */ + do { + struct ib_send_wr *bad_wr; + + if (unlikely((post_send(priv, qpn, first_wr, num_skbs, + &bad_wr)))) { + int done; + + ipoib_warn(priv, "post_send failed\n"); + + /* Get number of WR's that finished successfully */ + done = bad_wr - &priv->tx_wr[first_wr]; + + /* Handle 1 error */ + priv->stats.tx_errors++; + ib_dma_unmap_single(priv->ca, + priv->tx_sge[first_wr + done].addr, + priv->tx_sge[first_wr + done].length, + DMA_TO_DEVICE); + + /* Free failed WR & reset for WC handler to recognize */ + dev_kfree_skb_any(priv->tx_ring[bad_wr->wr_id].skb); + priv->tx_ring[bad_wr->wr_id].skb = NULL; + + /* Handle 'n' successes */ + if (done) { + dev->trans_start = jiffies; + address->last_send = priv->tx_head - (num_skbs - + done) - 1; + } + + /* Get count of skbs that were not tried */ + num_skbs -= (done + 1); + /* + 1 for WR that was tried & failed */ + + /* Get start index for next iteration */ + first_wr += (done + 1); + } else { + dev->trans_start = jiffies; + + address->last_send = priv->tx_head - 1; + num_skbs = 0; } - } + } while (num_skbs); } static void __ipoib_reap_ah(struct net_device *dev) - To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html