Hi Brain, > -----Original Message----- > From: Brian Norris [mailto:briannorris@xxxxxxxxxxxx] > Sent: 2017年5月20日 0:43 > To: Xinming Hu > Cc: Linux Wireless; Kalle Valo; Dmitry Torokhov; rajatja@xxxxxxxxxx; Zhiyuan > Yang; Cathy Luo; Xinming Hu; Ganapathi Bhat > Subject: [EXT] Re: [PATCH v3 5/6] mwifiex: do not aggregate tcp ack in usb tx > aggregation queue > > External Email > > ---------------------------------------------------------------------- > On Fri, May 19, 2017 at 09:06:44AM +0000, Xinming Hu wrote: > > From: Xinming Hu <huxm@xxxxxxxxxxx> > > > > Tcp ack should be send as soon to avoid throuput drop during receive > > tcp traffic. > > > > Signed-off-by: Xinming Hu <huxm@xxxxxxxxxxx> > > Signed-off-by: Cathy Luo <cluo@xxxxxxxxxxx> > > Signed-off-by: Ganapathi Bhat <gbhat@xxxxxxxxxxx> > > --- > > v2: same as v1 > > v3: avoid to use magic tcp flag (Kalle) > > --- > > drivers/net/wireless/marvell/mwifiex/11n_aggr.c | 4 ++++ > > drivers/net/wireless/marvell/mwifiex/decl.h | 1 + > > drivers/net/wireless/marvell/mwifiex/main.c | 26 > +++++++++++++++++++++++++ > > drivers/net/wireless/marvell/mwifiex/main.h | 1 + > > drivers/net/wireless/marvell/mwifiex/usb.c | 6 ++++-- > > 5 files changed, 36 insertions(+), 2 deletions(-) > > > > diff --git a/drivers/net/wireless/marvell/mwifiex/11n_aggr.c > > b/drivers/net/wireless/marvell/mwifiex/11n_aggr.c > > index e8ffb26..cbf3bc2 100644 > > --- a/drivers/net/wireless/marvell/mwifiex/11n_aggr.c > > +++ b/drivers/net/wireless/marvell/mwifiex/11n_aggr.c > > @@ -194,6 +194,10 @@ > > > > if (tx_info_src->flags & MWIFIEX_BUF_FLAG_TDLS_PKT) > > tx_info_aggr->flags |= MWIFIEX_BUF_FLAG_TDLS_PKT; > > + > > + if (tx_info_src->flags & MWIFIEX_BUF_FLAG_TCP_ACK) > > + tx_info_aggr->flags |= MWIFIEX_BUF_FLAG_TCP_ACK; > > + > > tx_info_aggr->flags |= MWIFIEX_BUF_FLAG_AGGR_PKT; > > skb_aggr->priority = skb_src->priority; > > skb_aggr->tstamp = skb_src->tstamp; > > diff --git a/drivers/net/wireless/marvell/mwifiex/decl.h > > b/drivers/net/wireless/marvell/mwifiex/decl.h > > index 188e4c3..0487420 100644 > > --- a/drivers/net/wireless/marvell/mwifiex/decl.h > > +++ b/drivers/net/wireless/marvell/mwifiex/decl.h > > @@ -89,6 +89,7 @@ > > #define MWIFIEX_BUF_FLAG_EAPOL_TX_STATUS BIT(3) > > #define MWIFIEX_BUF_FLAG_ACTION_TX_STATUS BIT(4) > > #define MWIFIEX_BUF_FLAG_AGGR_PKT BIT(5) > > +#define MWIFIEX_BUF_FLAG_TCP_ACK BIT(6) > > > > #define MWIFIEX_BRIDGED_PKTS_THR_HIGH 1024 > > #define MWIFIEX_BRIDGED_PKTS_THR_LOW 128 > > diff --git a/drivers/net/wireless/marvell/mwifiex/main.c > > b/drivers/net/wireless/marvell/mwifiex/main.c > > index 2c42191..b7d835c 100644 > > --- a/drivers/net/wireless/marvell/mwifiex/main.c > > +++ b/drivers/net/wireless/marvell/mwifiex/main.c > > @@ -851,6 +851,30 @@ struct sk_buff * > > return skb; > > } > > > > +static bool is_piggyback_tcp_ack(struct sk_buff *skb) { > > + struct ethhdr *ethh = NULL; > > + struct iphdr *iph = NULL; > > + struct tcphdr *tcph = NULL; > > + > > + ethh = (struct ethhdr *)skb->data; > > + if (ntohs(ethh->h_proto) != ETH_P_IP) > > + return false; > > What about IPv6? > > Also, what about all the protocols that you're *not* hacking this for? > Is the latency induced by aggregation really that poor? > > I'm not really a networking expert here, but this whole patch smells bad to me. > We didn't observe throughput drop due to ack block yet.. It was considered to be an optional enhance. Let's drop it in this patch serials. Regards, Simon > > + > > + iph = (struct iphdr *)((u8 *)ethh + sizeof(struct ethhdr)); > > + if (iph->protocol != IPPROTO_TCP) > > + return false; > > + > > + tcph = (struct tcphdr *)((u8 *)iph + iph->ihl * 4); > > + /* Piggyback ack without payload*/ > > + if (tcp_flag_word(tcph) == TCP_FLAG_ACK && > > + ntohs(iph->tot_len) <= (iph->ihl + tcph->doff) * 4) { > > + return true; > > + } > > + > > + return false; > > +} > > + > > /* > > * CFG802.11 network device handler for data transmission. > > */ > > @@ -904,6 +928,8 @@ struct sk_buff * > > tx_info->bss_num = priv->bss_num; > > tx_info->bss_type = priv->bss_type; > > tx_info->pkt_len = skb->len; > > + if (is_piggyback_tcp_ack(skb)) > > + tx_info->flags |= MWIFIEX_BUF_FLAG_TCP_ACK; > > > > multicast = is_multicast_ether_addr(skb->data); > > > > diff --git a/drivers/net/wireless/marvell/mwifiex/main.h > > b/drivers/net/wireless/marvell/mwifiex/main.h > > index 1f7e6c3..b0010a9 100644 > > --- a/drivers/net/wireless/marvell/mwifiex/main.h > > +++ b/drivers/net/wireless/marvell/mwifiex/main.h > > @@ -49,6 +49,7 @@ > > #include <linux/pm_runtime.h> > > #include <linux/slab.h> > > #include <linux/of_irq.h> > > +#include <linux/tcp.h> > > I dislike polluting the (driver-global) main.h with #include's that only are used > in one file. Especially when you talk about seemingly layer-violating TCP hacks. > Can you move this to main.c instead? > > Brian > > > > > #include "decl.h" > > #include "ioctl.h" > > diff --git a/drivers/net/wireless/marvell/mwifiex/usb.c > > b/drivers/net/wireless/marvell/mwifiex/usb.c > > index f230017..e9c3d43 100644 > > --- a/drivers/net/wireless/marvell/mwifiex/usb.c > > +++ b/drivers/net/wireless/marvell/mwifiex/usb.c > > @@ -934,6 +934,7 @@ static int mwifiex_usb_aggr_tx_data(struct > mwifiex_adapter *adapter, u8 ep, > > struct urb_context *context = NULL; > > struct txpd *local_tx_pd = > > (struct txpd *)((u8 *)skb->data + adapter->intf_hdr_len); > > + struct mwifiex_txinfo *tx_info = MWIFIEX_SKB_TXCB(skb); > > u8 f_send_aggr_buf = 0; > > u8 f_send_cur_buf = 0; > > u8 f_precopy_cur_buf = 0; > > @@ -989,8 +990,9 @@ static int mwifiex_usb_aggr_tx_data(struct > mwifiex_adapter *adapter, u8 ep, > > } > > } > > > > - if (local_tx_pd->flags & MWIFIEX_TxPD_POWER_MGMT_NULL_PACKET) { > > - /* Send NULL packet immediately*/ > > + if (local_tx_pd->flags & MWIFIEX_TxPD_POWER_MGMT_NULL_PACKET || > > + tx_info->flags & MWIFIEX_BUF_FLAG_TCP_ACK) { > > + /* Send NULL data/TCP ACK packet immediately*/ > > if (f_precopy_cur_buf) { > > if (skb_queue_empty(&port->tx_aggr.aggr_list)) { > > f_precopy_cur_buf = 0; > > -- > > 1.9.1 > >