From 08f7d8b69aaf137db8ee0a2d7c9e6cd6383ae250 Mon Sep 17 00:00:00 2001 From: Sara Sharon Date: Thu, 18 Oct 2018 11:03:06 +0300 Subject: [PATCH] iwlwifi: mvm: bring back mvm GSO code 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 Signed-off-by: Luca Coelho --- .../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 3b24cced3f6f..ebb3814dd922 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, -- 2.45.2