From: Sara Sharon <sara.sharon@xxxxxxxxx>
We have a slightly better TCP performance with GSO.
Add it back, it can co-exist with the code that builds
AMSDUs in mac80211.
Signed-off-by: Sara Sharon <sara.sharon@xxxxxxxxx>
Signed-off-by: Luca Coelho <luciano.coelho@xxxxxxxxx>
---
.../net/wireless/intel/iwlwifi/mvm/mac80211.c | 1 -
drivers/net/wireless/intel/iwlwifi/mvm/tx.c | 224 +++++++++++++++++-
2 files changed, 223 insertions(+), 2 deletions(-)
diff --git a/drivers/net/wireless/intel/iwlwifi/mvm/mac80211.c b/drivers/net/wireless/intel/iwlwifi/mvm/mac80211.c
index 5c0816b81298..9a4fef834941 100644
--- a/drivers/net/wireless/intel/iwlwifi/mvm/mac80211.c
+++ b/drivers/net/wireless/intel/iwlwifi/mvm/mac80211.c
@@ -754,7 +754,6 @@ int iwl_mvm_mac_setup_register(struct iwl_mvm *mvm)
}
hw->netdev_features |= mvm->cfg->features;
- hw->netdev_features &= ~(NETIF_F_TSO | NETIF_F_TSO6);
if (!iwl_mvm_is_csum_supported(mvm)) {
hw->netdev_features &= ~(IWL_TX_CSUM_NETIF_FLAGS |
NETIF_F_RXCSUM);
diff --git a/drivers/net/wireless/intel/iwlwifi/mvm/tx.c b/drivers/net/wireless/intel/iwlwifi/mvm/tx.c
index 2f2c355c13b0..da8b69c9468c 100644
--- a/drivers/net/wireless/intel/iwlwifi/mvm/tx.c
+++ b/drivers/net/wireless/intel/iwlwifi/mvm/tx.c
@@ -808,6 +808,197 @@ unsigned int iwl_mvm_max_amsdu_size(struct iwl_mvm *mvm,
mvm->fwrt.smem_cfg.lmac[lmac].txfifo_size[txf] - 256);
}
+#ifdef CONFIG_INET
+
+static int
+iwl_mvm_tx_tso_segment(struct sk_buff *skb, unsigned int num_subframes,
+ netdev_features_t netdev_flags,
+ struct sk_buff_head *mpdus_skb)
+{
+ struct sk_buff *tmp, *next;
+ struct ieee80211_hdr *hdr = (void *)skb->data;
+ char cb[sizeof(skb->cb)];
+ u16 i = 0;
+ unsigned int tcp_payload_len;
+ unsigned int mss = skb_shinfo(skb)->gso_size;
+ bool ipv4 = (skb->protocol == htons(ETH_P_IP));
+ u16 ip_base_id = ipv4 ? ntohs(ip_hdr(skb)->id) : 0;
+
+ skb_shinfo(skb)->gso_size = num_subframes * mss;
+ memcpy(cb, skb->cb, sizeof(cb));
+
+ next = skb_gso_segment(skb, netdev_flags);
+ skb_shinfo(skb)->gso_size = mss;
+ if (WARN_ON_ONCE(IS_ERR(next)))
+ return -EINVAL;
+ else if (next)
+ consume_skb(skb);
+
+ while (next) {
+ tmp = next;
+ next = tmp->next;
+
+ memcpy(tmp->cb, cb, sizeof(tmp->cb));
+ /*
+ * Compute the length of all the data added for the A-MSDU.
+ * This will be used to compute the length to write in the TX
+ * command. We have: SNAP + IP + TCP for n -1 subframes and
+ * ETH header for n subframes.
+ */
+ tcp_payload_len = skb_tail_pointer(tmp) -
+ skb_transport_header(tmp) -
+ tcp_hdrlen(tmp) + tmp->data_len;
+
+ if (ipv4)
+ ip_hdr(tmp)->id = htons(ip_base_id + i * num_subframes);
+
+ if (tcp_payload_len > mss) {
+ skb_shinfo(tmp)->gso_size = mss;
+ } else {
+ if (ieee80211_is_data_qos(hdr->frame_control)) {
+ u8 *qc;
+
+ if (ipv4)
+ ip_send_check(ip_hdr(tmp));
+
+ qc = ieee80211_get_qos_ctl((void *)tmp->data);
+ *qc &= ~IEEE80211_QOS_CTL_A_MSDU_PRESENT;
+ }
+ skb_shinfo(tmp)->gso_size = 0;
+ }
+
+ tmp->prev = NULL;
+ tmp->next = NULL;
+
+ __skb_queue_tail(mpdus_skb, tmp);
+ i++;
+ }
+
+ return 0;
+}
+
+static int iwl_mvm_tx_tso(struct iwl_mvm *mvm, struct sk_buff *skb,
+ struct ieee80211_tx_info *info,
+ struct ieee80211_sta *sta,
+ struct sk_buff_head *mpdus_skb)
+{
+ struct iwl_mvm_sta *mvmsta = iwl_mvm_sta_from_mac80211(sta);
+ struct ieee80211_hdr *hdr = (void *)skb->data;
+ unsigned int mss = skb_shinfo(skb)->gso_size;
+ unsigned int num_subframes, tcp_payload_len, subf_len, max_amsdu_len;
+ u16 snap_ip_tcp, pad;
+ unsigned int dbg_max_amsdu_len;
+ netdev_features_t netdev_flags = NETIF_F_CSUM_MASK | NETIF_F_SG;
+ u8 tid;
+
+ snap_ip_tcp = 8 + skb_transport_header(skb) - skb_network_header(skb) +
+ tcp_hdrlen(skb);
+
+ dbg_max_amsdu_len = READ_ONCE(mvm->max_amsdu_len);
+
+ if (!mvmsta->max_amsdu_len ||
+ !ieee80211_is_data_qos(hdr->frame_control) ||
+ (!mvmsta->amsdu_enabled && !dbg_max_amsdu_len))
+ return iwl_mvm_tx_tso_segment(skb, 1, netdev_flags, mpdus_skb);
+
+ /*
+ * Do not build AMSDU for IPv6 with extension headers.
+ * ask stack to segment and checkum the generated MPDUs for us.
+ */
+ if (skb->protocol == htons(ETH_P_IPV6) &&
+ ((struct ipv6hdr *)skb_network_header(skb))->nexthdr !=
+ IPPROTO_TCP) {
+ netdev_flags &= ~NETIF_F_CSUM_MASK;
+ return iwl_mvm_tx_tso_segment(skb, 1, netdev_flags, mpdus_skb);
+ }
+
+ tid = ieee80211_get_tid(hdr);
+ if (WARN_ON_ONCE(tid >= IWL_MAX_TID_COUNT))
+ return -EINVAL;
+
+ /*
+ * No need to lock amsdu_in_ampdu_allowed since it can't be modified
+ * during an BA session.
+ */
+ if (info->flags & IEEE80211_TX_CTL_AMPDU &&
+ !mvmsta->tid_data[tid].amsdu_in_ampdu_allowed)
+ return iwl_mvm_tx_tso_segment(skb, 1, netdev_flags, mpdus_skb);
+
+ if (iwl_mvm_vif_low_latency(iwl_mvm_vif_from_mac80211(mvmsta->vif)) ||
+ !(mvmsta->amsdu_enabled & BIT(tid)))
+ return iwl_mvm_tx_tso_segment(skb, 1, netdev_flags, mpdus_skb);
+
+ max_amsdu_len = iwl_mvm_max_amsdu_size(mvm, sta, tid);
+
+ if (unlikely(dbg_max_amsdu_len))
+ max_amsdu_len = min_t(unsigned int, max_amsdu_len,
+ dbg_max_amsdu_len);
+
+ /*
+ * Limit A-MSDU in A-MPDU to 4095 bytes when VHT is not
+ * supported. This is a spec requirement (IEEE 802.11-2015
+ * section 8.7.3 NOTE 3).
+ */
+ if (info->flags & IEEE80211_TX_CTL_AMPDU &&
+ !sta->vht_cap.vht_supported)
+ max_amsdu_len = min_t(unsigned int, max_amsdu_len, 4095);
+
+ /* Sub frame header + SNAP + IP header + TCP header + MSS */
+ subf_len = sizeof(struct ethhdr) + snap_ip_tcp + mss;
+ pad = (4 - subf_len) & 0x3;
+
+ /*
+ * If we have N subframes in the A-MSDU, then the A-MSDU's size is
+ * N * subf_len + (N - 1) * pad.
+ */
+ num_subframes = (max_amsdu_len + pad) / (subf_len + pad);
+
+ if (sta->max_amsdu_subframes &&
+ num_subframes > sta->max_amsdu_subframes)
+ num_subframes = sta->max_amsdu_subframes;
+
+ tcp_payload_len = skb_tail_pointer(skb) - skb_transport_header(skb) -
+ tcp_hdrlen(skb) + skb->data_len;
+
+ /*
+ * Make sure we have enough TBs for the A-MSDU:
+ * 2 for each subframe
+ * 1 more for each fragment
+ * 1 more for the potential data in the header
+ */
+ if ((num_subframes * 2 + skb_shinfo(skb)->nr_frags + 1) >
+ mvm->trans->max_skb_frags)
+ num_subframes = 1;
+
+ if (num_subframes > 1)
+ *ieee80211_get_qos_ctl(hdr) |= IEEE80211_QOS_CTL_A_MSDU_PRESENT;
+
+ /* This skb fits in one single A-MSDU */
+ if (num_subframes * mss >= tcp_payload_len) {
+ __skb_queue_tail(mpdus_skb, skb);
+ return 0;
+ }
+
+ /*
+ * Trick the segmentation function to make it
+ * create SKBs that can fit into one A-MSDU.
+ */
+ return iwl_mvm_tx_tso_segment(skb, num_subframes, netdev_flags,
+ mpdus_skb);
+}
+#else /* CONFIG_INET */
+static int iwl_mvm_tx_tso(struct iwl_mvm *mvm, struct sk_buff *skb,
+ struct ieee80211_tx_info *info,
+ struct ieee80211_sta *sta,
+ struct sk_buff_head *mpdus_skb)
+{
+ /* Impossible to get TSO with CONFIG_INET */
+ WARN_ON(1);
+
+ return -1;
+}
+#endif
+
/* Check if there are any timed-out TIDs on a given shared TXQ */
static bool iwl_mvm_txq_should_update(struct iwl_mvm *mvm, int txq_id)
{
@@ -986,6 +1177,9 @@ int iwl_mvm_tx_skb(struct iwl_mvm *mvm, struct sk_buff *skb,
{
struct iwl_mvm_sta *mvmsta = iwl_mvm_sta_from_mac80211(sta);
struct ieee80211_tx_info info;
+ struct sk_buff_head mpdus_skbs;
+ unsigned int payload_len;
+ int ret;
if (WARN_ON_ONCE(!mvmsta))
return -1;
@@ -995,7 +1189,35 @@ int iwl_mvm_tx_skb(struct iwl_mvm *mvm, struct sk_buff *skb,
memcpy(&info, skb->cb, sizeof(info));
- return iwl_mvm_tx_mpdu(mvm, skb, &info, sta);
+ if (!skb_is_gso(skb))
+ return iwl_mvm_tx_mpdu(mvm, skb, &info, sta);
+
+ payload_len = skb_tail_pointer(skb) - skb_transport_header(skb) -
+ tcp_hdrlen(skb) + skb->data_len;
+
+ if (payload_len <= skb_shinfo(skb)->gso_size)
+ return iwl_mvm_tx_mpdu(mvm, skb, &info, sta);
+
+ __skb_queue_head_init(&mpdus_skbs);
+
+ ret = iwl_mvm_tx_tso(mvm, skb, &info, sta, &mpdus_skbs);
+ if (ret)
+ return ret;
+
+ if (WARN_ON(skb_queue_empty(&mpdus_skbs)))
+ return ret;
+
+ while (!skb_queue_empty(&mpdus_skbs)) {
+ skb = __skb_dequeue(&mpdus_skbs);
+
+ ret = iwl_mvm_tx_mpdu(mvm, skb, &info, sta);
+ if (ret) {
+ __skb_queue_purge(&mpdus_skbs);
+ return ret;
+ }
+ }
+
+ return 0;
}
static void iwl_mvm_check_ratid_empty(struct iwl_mvm *mvm,
--
2.20.1
