[PATCH 2.6.25 2/4]S2io: Multiqueue network device support - FIFO selection based on L4 ports

[PATCH 2.6.25 2/4]S2io: Multiqueue network device support - FIFO selection based on L4 ports

[Sreenivasa Honnur]

- Resubmit #2
- Transmit fifo selection based on TCP/UDP ports.
- Added tx_steering_type loadable parameter for transmit fifo selection.
  0x0 NO_STEERING: Default FIFO is selected.
  0x1 TX_PRIORITY_STEERING: FIFO is selected based on skb->priority.
  0x2 TX_DEFAULT_STEERING: FIFO is selected based on L4 Ports.

Signed-off-by: Surjit Reang <surjit.reang@neterion.com>
Signed-off-by: Ramkrishna Vepa <ram.vepa@neterion.com>
---
diff -Nurp 2-0-26-18-1/drivers/net/s2io.c 2-0-26-18-2/drivers/net/s2io.c
--- 2-0-26-18-1/drivers/net/s2io.c	2008-02-15 05:15:41.000000000 +0530
+++ 2-0-26-18-2/drivers/net/s2io.c	2008-02-15 05:16:36.000000000 +0530
@@ -458,7 +458,7 @@ MODULE_VERSION(DRV_VERSION);
 
 
 /* Module Loadable parameters. */
-S2IO_PARM_INT(tx_fifo_num, 1);
+S2IO_PARM_INT(tx_fifo_num, FIFO_DEFAULT_NUM);
 S2IO_PARM_INT(rx_ring_num, 1);
 S2IO_PARM_INT(multiq, 0);
 S2IO_PARM_INT(rx_ring_mode, 1);
@@ -470,6 +470,8 @@ S2IO_PARM_INT(shared_splits, 0);
 S2IO_PARM_INT(tmac_util_period, 5);
 S2IO_PARM_INT(rmac_util_period, 5);
 S2IO_PARM_INT(l3l4hdr_size, 128);
+/* 0 is no steering, 1 is Priority steering, 2 is Default steering */
+S2IO_PARM_INT(tx_steering_type, TX_DEFAULT_STEERING);
 /* Frequency of Rx desc syncs expressed as power of 2 */
 S2IO_PARM_INT(rxsync_frequency, 3);
 /* Interrupt type. Values can be 0(INTA), 2(MSI_X) */
@@ -4114,7 +4116,9 @@ static int s2io_xmit(struct sk_buff *skb
 	struct fifo_info *fifo = NULL;
 	struct mac_info *mac_control;
 	struct config_param *config;
+	int do_spin_lock = 1;
 	int offload_type;
+	int enable_per_list_interrupt = 0;
 	struct swStat *stats = &sp->mac_control.stats_info->sw_stat;
 
 	mac_control = &sp->mac_control;
@@ -4136,15 +4140,52 @@ static int s2io_xmit(struct sk_buff *skb
 	}
 
 	queue = 0;
-	/* Get Fifo number to Transmit based on vlan priority */
 	if (sp->vlgrp && vlan_tx_tag_present(skb))
 		vlan_tag = vlan_tx_tag_get(skb);
+	if (sp->config.tx_steering_type == TX_DEFAULT_STEERING) {
+		if (skb->protocol == htons(ETH_P_IP)) {
+			struct iphdr *ip;
+			struct tcphdr *th;
+			ip = ip_hdr(skb);
+
+			if ((ip->frag_off & htons(IP_OFFSET|IP_MF)) == 0) {
+				th = (struct tcphdr *)(((unsigned char *)ip) +
+						ip->ihl*4);
+
+				if (ip->protocol == IPPROTO_TCP) {
+					queue_len = sp->total_tcp_fifos;
+					queue = (ntohs(th->source) +
+							ntohs(th->dest)) &
+					    sp->fifo_selector[queue_len - 1];
+					if (queue >= queue_len)
+						queue = queue_len - 1;
+				} else if (ip->protocol == IPPROTO_UDP) {
+					queue_len = sp->total_udp_fifos;
+					queue = (ntohs(th->source) +
+							ntohs(th->dest)) &
+					    sp->fifo_selector[queue_len - 1];
+					if (queue >= queue_len)
+						queue = queue_len - 1;
+					queue += sp->udp_fifo_idx;
+					if (skb->len > 1024)
+						enable_per_list_interrupt = 1;
+					do_spin_lock = 0;
+				}
+			}
+		}
+	} else if (sp->config.tx_steering_type == TX_PRIORITY_STEERING)
+		/* get fifo number based on skb->priority value */
+		queue = config->fifo_mapping
+					[skb->priority & (MAX_TX_FIFOS - 1)];
+	fifo = &mac_control->fifos[queue];
 
-	/* get fifo number based on skb->priority value */
-	queue = config->fifo_mapping[skb->priority & (MAX_TX_FIFOS - 1)];
+	if (do_spin_lock)
+		spin_lock_irqsave(&fifo->tx_lock, flags);
+	else {
+		if (unlikely(!spin_trylock_irqsave(&fifo->tx_lock, flags)))
+			return NETDEV_TX_LOCKED;
+	}
 
-	fifo = &mac_control->fifos[queue];
-	spin_lock_irqsave(&fifo->tx_lock, flags);
 #ifdef CONFIG_NETDEVICES_MULTIQUEUE
 	if (sp->config.multiq) {
 		if (__netif_subqueue_stopped(dev, fifo->fifo_no)) {
@@ -4188,7 +4229,9 @@ static int s2io_xmit(struct sk_buff *skb
 	txdp->Control_1 |= TXD_GATHER_CODE_FIRST;
 	txdp->Control_1 |= TXD_LIST_OWN_XENA;
 	txdp->Control_2 |= TXD_INT_NUMBER(fifo->fifo_no);
-
+	if (enable_per_list_interrupt)
+		if (put_off & (queue_len >> 5))
+			txdp->Control_2 |= TXD_INT_TYPE_PER_LIST;
 	if (vlan_tag) {
 		txdp->Control_2 |= TXD_VLAN_ENABLE;
 		txdp->Control_2 |= TXD_VLAN_TAG(vlan_tag);
@@ -7622,13 +7665,15 @@ static int s2io_verify_parm(struct pci_d
 	u8 *dev_multiq)
 {
 	if ((tx_fifo_num > MAX_TX_FIFOS) ||
-		(tx_fifo_num < FIFO_DEFAULT_NUM)) {
+		(tx_fifo_num < 1)) {
 		DBG_PRINT(ERR_DBG, "s2io: Requested number of tx fifos "
 			"(%d) not supported\n", tx_fifo_num);
-		tx_fifo_num =
-			((tx_fifo_num > MAX_TX_FIFOS)? MAX_TX_FIFOS :
-			((tx_fifo_num < FIFO_DEFAULT_NUM) ? FIFO_DEFAULT_NUM :
-			tx_fifo_num));
+
+		if (tx_fifo_num < 1)
+			tx_fifo_num = 1;
+		else
+			tx_fifo_num = MAX_TX_FIFOS;
+
 		DBG_PRINT(ERR_DBG, "s2io: Default to %d ", tx_fifo_num);
 		DBG_PRINT(ERR_DBG, "tx fifos\n");
 	}
@@ -7639,10 +7684,23 @@ static int s2io_verify_parm(struct pci_d
 		multiq = 0;
 	}
 #endif
-	/* if multiqueue is enabled configure all fifos */
-	if (multiq) {
-		tx_fifo_num = MAX_TX_FIFOS;
+	if (multiq)
 		*dev_multiq = multiq;
+
+	if (tx_steering_type && (1 == tx_fifo_num)) {
+		if (tx_steering_type != TX_DEFAULT_STEERING)
+			DBG_PRINT(ERR_DBG,
+				"s2io: Tx steering is not supported with "
+				"one fifo. Disabling Tx steering.\n");
+		tx_steering_type = NO_STEERING;
+	}
+
+	if ((tx_steering_type < NO_STEERING) ||
+		(tx_steering_type > TX_DEFAULT_STEERING)) {
+		DBG_PRINT(ERR_DBG, "s2io: Requested transmit steering not "
+			 "supported\n");
+		DBG_PRINT(ERR_DBG, "s2io: Disabling transmit steering\n");
+		tx_steering_type = NO_STEERING;
 	}
 
 	if ( rx_ring_num > 8) {
@@ -7773,7 +7831,7 @@ s2io_init_nic(struct pci_dev *pdev, cons
 	}
 #ifdef CONFIG_NETDEVICES_MULTIQUEUE
 	if (dev_multiq)
-		dev = alloc_etherdev_mq(sizeof(struct s2io_nic), MAX_TX_FIFOS);
+		dev = alloc_etherdev_mq(sizeof(struct s2io_nic), tx_fifo_num);
 	else
 #endif
 	dev = alloc_etherdev(sizeof(struct s2io_nic));
@@ -7824,11 +7882,33 @@ s2io_init_nic(struct pci_dev *pdev, cons
 	config = &sp->config;
 
 	config->napi = napi;
+	config->tx_steering_type = tx_steering_type;
 
 	/* Tx side parameters. */
-	config->tx_fifo_num = tx_fifo_num;
+	if (config->tx_steering_type == TX_PRIORITY_STEERING)
+		config->tx_fifo_num = MAX_TX_FIFOS;
+	else
+		config->tx_fifo_num = tx_fifo_num;
+
+	/* Initialize the fifos used for tx steering */
+	if (config->tx_fifo_num < 5) {
+			if (config->tx_fifo_num  == 1)
+				sp->total_tcp_fifos = 1;
+			else
+				sp->total_tcp_fifos = config->tx_fifo_num - 1;
+			sp->udp_fifo_idx = config->tx_fifo_num - 1;
+			sp->total_udp_fifos = 1;
+			sp->other_fifo_idx = sp->total_tcp_fifos - 1;
+	} else {
+		sp->total_tcp_fifos = (tx_fifo_num - FIFO_UDP_MAX_NUM -
+						FIFO_OTHER_MAX_NUM);
+		sp->udp_fifo_idx = sp->total_tcp_fifos;
+		sp->total_udp_fifos = FIFO_UDP_MAX_NUM;
+		sp->other_fifo_idx = sp->udp_fifo_idx + FIFO_UDP_MAX_NUM;
+	}
+
 	config->multiq = dev_multiq;
-	for (i = 0; i < MAX_TX_FIFOS; i++) {
+	for (i = 0; i < config->tx_fifo_num; i++) {
 		config->tx_cfg[i].fifo_len = tx_fifo_len[i];
 		config->tx_cfg[i].fifo_priority = i;
 	}
@@ -7837,6 +7917,11 @@ s2io_init_nic(struct pci_dev *pdev, cons
 	for (i = 0; i < MAX_TX_FIFOS; i++)
 		config->fifo_mapping[i] = fifo_map[config->tx_fifo_num - 1][i];
 
+	/* map the hashing selector table to the configured fifos */
+	for (i = 0; i < config->tx_fifo_num; i++)
+		sp->fifo_selector[i] = fifo_selector[i];
+
+
 	config->tx_intr_type = TXD_INT_TYPE_UTILZ;
 	for (i = 0; i < config->tx_fifo_num; i++) {
 		config->tx_cfg[i].f_no_snoop =
@@ -8113,6 +8198,20 @@ s2io_init_nic(struct pci_dev *pdev, cons
 		DBG_PRINT(ERR_DBG, "%s: Multiqueue support disabled\n",
 			dev->name);
 
+	switch (sp->config.tx_steering_type) {
+	case NO_STEERING:
+		DBG_PRINT(ERR_DBG, "%s: No steering enabled for"
+			" transmit\n", dev->name);
+			break;
+	case TX_PRIORITY_STEERING:
+		DBG_PRINT(ERR_DBG, "%s: Priority steering enabled for"
+			" transmit\n", dev->name);
+		break;
+	case TX_DEFAULT_STEERING:
+		DBG_PRINT(ERR_DBG, "%s: Default steering enabled for"
+			" transmit\n", dev->name);
+	}
+
 	if (sp->lro)
 		DBG_PRINT(ERR_DBG, "%s: Large receive offload enabled\n",
 			  dev->name);
diff -Nurp 2-0-26-18-1/drivers/net/s2io.h 2-0-26-18-2/drivers/net/s2io.h
--- 2-0-26-18-1/drivers/net/s2io.h	2008-02-15 05:15:49.000000000 +0530
+++ 2-0-26-18-2/drivers/net/s2io.h	2008-02-15 05:16:45.000000000 +0530
@@ -360,7 +360,10 @@ struct stat_block {
 #define MAX_TX_FIFOS 8
 #define MAX_RX_RINGS 8
 
-#define FIFO_DEFAULT_NUM	1
+#define FIFO_DEFAULT_NUM	5
+#define FIFO_UDP_MAX_NUM			2 /* 0 - even, 1 -odd ports */
+#define FIFO_OTHER_MAX_NUM			1
+
 
 #define MAX_RX_DESC_1  (MAX_RX_RINGS * MAX_RX_BLOCKS_PER_RING * 127 )
 #define MAX_RX_DESC_2  (MAX_RX_RINGS * MAX_RX_BLOCKS_PER_RING * 85 )
@@ -379,6 +382,8 @@ static int fifo_map[][MAX_TX_FIFOS] = {
 	{0, 1, 2, 3, 4, 5, 6, 7},
 };
 
+static u16 fifo_selector[MAX_TX_FIFOS] = {0, 1, 3, 3, 7, 7, 7, 7};
+
 /* Maintains Per FIFO related information. */
 struct tx_fifo_config {
 #define	MAX_AVAILABLE_TXDS	8192
@@ -431,6 +436,12 @@ struct config_param {
 /* Tx Side */
 	u32 tx_fifo_num;	/*Number of Tx FIFOs */
 
+	/* 0-No steering, 1-Priority steering, 2-Default fifo map */
+#define	NO_STEERING				0
+#define	TX_PRIORITY_STEERING			0x1
+#define TX_DEFAULT_STEERING 			0x2
+	u8 tx_steering_type;
+
 	u8 fifo_mapping[MAX_TX_FIFOS];
 	struct tx_fifo_config tx_cfg[MAX_TX_FIFOS];	/*Per-Tx FIFO config */
 	u32 max_txds;		/*Max no. of Tx buffer descriptor per TxDL */
@@ -895,6 +906,27 @@ struct s2io_nic {
 	 */
 	int rx_csum;
 
+	/* Below variables are used for fifo selection to transmit a packet */
+	u16 fifo_selector[MAX_TX_FIFOS];
+
+	/* Total fifos for tcp packets */
+	u8 total_tcp_fifos;
+
+	/*
+	* Beginning index of udp for udp packets
+	* Value will be equal to
+	* (tx_fifo_num - FIFO_UDP_MAX_NUM - FIFO_OTHER_MAX_NUM)
+	*/
+	u8 udp_fifo_idx;
+
+	u8 total_udp_fifos;
+
+	/*
+	 * Beginning index of fifo for all other packets
+	 * Value will be equal to (tx_fifo_num - FIFO_OTHER_MAX_NUM)
+	*/
+	u8 other_fifo_idx;
+
 	/*  after blink, the adapter must be restored with original
 	 *  values.
 	 */

Re: [PATCH 2.6.25 2/4]S2io: Multiqueue network device support - FIFO selection based on L4 ports

[Patrick McHardy]

Sreenivasa Honnur wrote:
> - Resubmit #2
> - Transmit fifo selection based on TCP/UDP ports.
> - Added tx_steering_type loadable parameter for transmit fifo selection.
>   0x0 NO_STEERING: Default FIFO is selected.
>   0x1 TX_PRIORITY_STEERING: FIFO is selected based on skb->priority.
>   0x2 TX_DEFAULT_STEERING: FIFO is selected based on L4 Ports.
>   

Why duplicate the generic multiqueue classification?

RE: [PATCH 2.6.25 2/4]S2io: Multiqueue network device support - FIFO selection based on L4 ports

[Ramkrishna Vepa]

> Sreenivasa Honnur wrote:
> > - Resubmit #2
> > - Transmit fifo selection based on TCP/UDP ports.
> > - Added tx_steering_type loadable parameter for transmit fifo
selection.
> >   0x0 NO_STEERING: Default FIFO is selected.
> >   0x1 TX_PRIORITY_STEERING: FIFO is selected based on skb->priority.
> >   0x2 TX_DEFAULT_STEERING: FIFO is selected based on L4 Ports.
> >
> 
> Why duplicate the generic multiqueue classification?
[Ram] Could you be more specific?

Ram
> 

Re: [PATCH 2.6.25 2/4]S2io: Multiqueue network device support - FIFO selection based on L4 ports

[Patrick McHardy]

Ramkrishna Vepa wrote:
>> Sreenivasa Honnur wrote:
>>     
>>> - Resubmit #2
>>> - Transmit fifo selection based on TCP/UDP ports.
>>> - Added tx_steering_type loadable parameter for transmit fifo
>>>       
> selection.
>   
>>>   0x0 NO_STEERING: Default FIFO is selected.
>>>   0x1 TX_PRIORITY_STEERING: FIFO is selected based on skb->priority.
>>>   0x2 TX_DEFAULT_STEERING: FIFO is selected based on L4 Ports.
>>>
>>>       
>> Why duplicate the generic multiqueue classification?
>>     
> [Ram] Could you be more specific?
>   

The generic multiqueue support classifies packets by setting
skb->queue_mapping using qdisc classifiers, which is more
flexible and avoids using module parameters.

Re: [PATCH 2.6.25 2/4]S2io: Multiqueue network device support - FIFO selection based on L4 ports

[David Miller]

From: Patrick McHardy <kaber@trash.net>
Date: Thu, 21 Feb 2008 00:08:52 +0100

> Ramkrishna Vepa wrote:
> >> Sreenivasa Honnur wrote:
> >>     
> >>> - Resubmit #2
> >>> - Transmit fifo selection based on TCP/UDP ports.
> >>> - Added tx_steering_type loadable parameter for transmit fifo
> >>>       
> > selection.
> >   
> >>>   0x0 NO_STEERING: Default FIFO is selected.
> >>>   0x1 TX_PRIORITY_STEERING: FIFO is selected based on skb->priority.
> >>>   0x2 TX_DEFAULT_STEERING: FIFO is selected based on L4 Ports.
> >>>
> >>>       
> >> Why duplicate the generic multiqueue classification?
> >>     
> > [Ram] Could you be more specific?
> >   
> 
> The generic multiqueue support classifies packets by setting
> skb->queue_mapping using qdisc classifiers, which is more
> flexible and avoids using module parameters.

But it doesn't do what these multiqueue TX queue hardware devices
want.  These devices don't want packet scheduler "classification",
they want load balancing using some key (current cpu number,
hashing on the packet headers, etc.)  And that's not what our
packet scheduler classifiers do or should do.

We don't want to have to tell people "you have to run 'tc' magic
foo to use all of the TX queues on your network card."  That's
completely unreasonable and stupid.

We have to resolve this somehow, and there have been many discussions
about this a month or so ago.

Re: [PATCH 2.6.25 2/4]S2io: Multiqueue network device support - FIFO selection based on L4 ports

[Patrick McHardy]

David Miller wrote:
> From: Patrick McHardy <kaber@trash.net>
> Date: Thu, 21 Feb 2008 00:08:52 +0100
>
>   
>> Ramkrishna Vepa wrote:
>>     
>>>> Sreenivasa Honnur wrote:
>>>>     
>>>>         
>>>>> - Resubmit #2
>>>>> - Transmit fifo selection based on TCP/UDP ports.
>>>>> - Added tx_steering_type loadable parameter for transmit fifo
>>>>>       
>>>>>           
>>> selection.
>>>   
>>>       
>>>>>   0x0 NO_STEERING: Default FIFO is selected.
>>>>>   0x1 TX_PRIORITY_STEERING: FIFO is selected based on skb->priority.
>>>>>   0x2 TX_DEFAULT_STEERING: FIFO is selected based on L4 Ports.
>>>>>
>>>>>       
>>>>>           
>>>> Why duplicate the generic multiqueue classification?
>>>>     
>>>>         
>>> [Ram] Could you be more specific?
>>>   
>>>       
>> The generic multiqueue support classifies packets by setting
>> skb->queue_mapping using qdisc classifiers, which is more
>> flexible and avoids using module parameters.
>>     
>
> But it doesn't do what these multiqueue TX queue hardware devices
> want.  These devices don't want packet scheduler "classification",
> they want load balancing using some key (current cpu number,
> hashing on the packet headers, etc.)  And that's not what our
> packet scheduler classifiers do or should do.
>   

Its what the flow classifier does :)
> We don't want to have to tell people "you have to run 'tc' magic
> foo to use all of the TX queues on your network card."  That's
> completely unreasonable and stupid.
>
> We have to resolve this somehow, and there have been many discussions
> about this a month or so ago.
>   

I see. I missed those discussions, but this has already been
agreed on, fine by me. It would still be preferable to use
queue_mapping instead of priority IMO, even if its activated
by a module parameter, since that leaves the option to use
classifiers.

Re: [PATCH 2.6.25 2/4]S2io: Multiqueue network device support - FIFO selection based on L4 ports

[David Miller]

From: Patrick McHardy <kaber@trash.net>
Date: Thu, 21 Feb 2008 00:15:13 +0100

> I missed those discussions, but this has already been agreed on,
> fine by me. It would still be preferable to use queue_mapping
> instead of priority IMO, even if its activated by a module
> parameter, since that leaves the option to use classifiers.

I think the driver should compute the value in it's transmit
routine and keep the value local.  It shouldn't be setting
skb->foo values at all, they don't belong to the driver
and this could confuse other code.

Re: [PATCH 2.6.25 2/4]S2io: Multiqueue network device support - FIFO selection based on L4 ports

[Patrick McHardy]

David Miller wrote:
> From: Patrick McHardy <kaber@trash.net>
> Date: Thu, 21 Feb 2008 00:15:13 +0100
>
>   
>> I missed those discussions, but this has already been agreed on,
>> fine by me. It would still be preferable to use queue_mapping
>> instead of priority IMO, even if its activated by a module
>> parameter, since that leaves the option to use classifiers.
>>     
>
> I think the driver should compute the value in it's transmit
> routine and keep the value local.  It shouldn't be setting
> skb->foo values at all, they don't belong to the driver
> and this could confuse other code.
>   

Yes, I didn't meant it should set anything, but on of the options
this patch introduces is to _use_ skb->priority for classification,
so the classification is already external, in which case it might
as well offer the full flexibility (as one option) to use qdisc
classifiers.

RE: [PATCH 2.6.25 2/4]S2io: Multiqueue network device support - FIFO selection based on L4 ports

[Ramkrishna Vepa]

> From: Patrick McHardy [mailto:kaber@trash.net]
> Sent: Wednesday, February 20, 2008 3:22 PM
> To: David Miller
> Cc: Ramkrishna Vepa; Sreenivasa Honnur; netdev@vger.kernel.org;
> jeff@garzik.org; support
> Subject: Re: [PATCH 2.6.25 2/4]S2io: Multiqueue network device support
-
> FIFO selection based on L4 ports
> 
> David Miller wrote:
> > From: Patrick McHardy <kaber@trash.net>
> > Date: Thu, 21 Feb 2008 00:15:13 +0100
> >
> >
> >> I missed those discussions, but this has already been agreed on,
> >> fine by me. It would still be preferable to use queue_mapping
> >> instead of priority IMO, even if its activated by a module
> >> parameter, since that leaves the option to use classifiers.
> >>
> >
> > I think the driver should compute the value in it's transmit
> > routine and keep the value local.  It shouldn't be setting
> > skb->foo values at all, they don't belong to the driver
> > and this could confuse other code.
> >
> 
> Yes, I didn't meant it should set anything, but on of the options
> this patch introduces is to _use_ skb->priority for classification,
> so the classification is already external, in which case it might
> as well offer the full flexibility (as one option) to use qdisc
> classifiers.
[Ram] Yes, this should be possible. We can add an additional option to
use qdisc classifiers and submit it as a patch later on.

Ram

Re: [PATCH 2.6.25 2/4]S2io: Multiqueue network device support - FIFO selection based on L4 ports

[Jeff Garzik]

David Miller wrote:
> From: Patrick McHardy <kaber@trash.net>
> Date: Thu, 21 Feb 2008 00:08:52 +0100
> 
>> Ramkrishna Vepa wrote:
>>>> Sreenivasa Honnur wrote:
>>>>     
>>>>> - Resubmit #2
>>>>> - Transmit fifo selection based on TCP/UDP ports.
>>>>> - Added tx_steering_type loadable parameter for transmit fifo
>>>>>       
>>> selection.
>>>   
>>>>>   0x0 NO_STEERING: Default FIFO is selected.
>>>>>   0x1 TX_PRIORITY_STEERING: FIFO is selected based on skb->priority.
>>>>>   0x2 TX_DEFAULT_STEERING: FIFO is selected based on L4 Ports.
>>>>>
>>>>>       
>>>> Why duplicate the generic multiqueue classification?
>>>>     
>>> [Ram] Could you be more specific?
>>>   
>> The generic multiqueue support classifies packets by setting
>> skb->queue_mapping using qdisc classifiers, which is more
>> flexible and avoids using module parameters.
> 
> But it doesn't do what these multiqueue TX queue hardware devices
> want.  These devices don't want packet scheduler "classification",
> they want load balancing using some key (current cpu number,
> hashing on the packet headers, etc.)  And that's not what our
> packet scheduler classifiers do or should do.
> 
> We don't want to have to tell people "you have to run 'tc' magic
> foo to use all of the TX queues on your network card."  That's
> completely unreasonable and stupid.
> 
> We have to resolve this somehow, and there have been many discussions
> about this a month or so ago.

So where does that leave this patch?  :)

	Jeff