[v2] idpf: change IRQ naming to match netdev and ethtool queue numbering

[iwl-net PATCH v2] idpf: change IRQ naming to match netdev and ethtool queue numbering

Posted by Brian Vazquez 6 hours ago

The code uses the vidx for the IRQ name but that doesn't match ethtool
reporting or netdev naming, this makes it hard to tune the device and
associate queues with IRQs. Sequentially requesting irqs starting from
'0' makes the output consistent.

Before:

ethtool -L eth1 tx 1 combined 3

grep . /proc/irq/*/*idpf*/../smp_affinity_list
/proc/irq/67/idpf-Mailbox-0/../smp_affinity_list:0-55,112-167
/proc/irq/68/idpf-eth1-TxRx-1/../smp_affinity_list:0
/proc/irq/70/idpf-eth1-TxRx-3/../smp_affinity_list:1
/proc/irq/71/idpf-eth1-TxRx-4/../smp_affinity_list:2
/proc/irq/72/idpf-eth1-Tx-5/../smp_affinity_list:3

ethtool -S eth1 | grep -v ': 0'
NIC statistics:
     tx_q-0_pkts: 1002
     tx_q-1_pkts: 2679
     tx_q-2_pkts: 1113
     tx_q-3_pkts: 1192 <----- tx_q-3 vs idpf-eth1-Tx-5
     rx_q-0_pkts: 1143
     rx_q-1_pkts: 3172
     rx_q-2_pkts: 1074

After:

ethtool -L eth1 tx 1 combined 3

grep . /proc/irq/*/*idpf*/../smp_affinity_list

/proc/irq/67/idpf-Mailbox-0/../smp_affinity_list:0-55,112-167
/proc/irq/68/idpf-eth1-TxRx-0/../smp_affinity_list:0
/proc/irq/70/idpf-eth1-TxRx-1/../smp_affinity_list:1
/proc/irq/71/idpf-eth1-TxRx-2/../smp_affinity_list:2
/proc/irq/72/idpf-eth1-Tx-3/../smp_affinity_list:3

ethtool -S eth1 | grep -v ': 0'
NIC statistics:
     tx_q-0_pkts: 118
     tx_q-1_pkts: 134
     tx_q-2_pkts: 228
     tx_q-3_pkts: 138 <--- tx_q-3 matches idpf-eth1-Tx-3
     rx_q-0_pkts: 111
     rx_q-1_pkts: 366
     rx_q-2_pkts: 120

Fixes: d4d558718266 ("idpf: initialize interrupts and enable vport")
Signed-off-by: Brian Vazquez <brianvv@google.com>
Reviewed-by: Brett Creeley <brett.creeley@amd.com>
Reviewed-by: Aleksandr Loktionov <aleksandr.loktionov@intel.com>
---
V2: Add mising Fixes tag

 drivers/net/ethernet/intel/idpf/idpf_txrx.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/intel/idpf/idpf_txrx.c b/drivers/net/ethernet/intel/idpf/idpf_txrx.c
index c2a1fe3c79ec..c1f8dfc570ce 100644
--- a/drivers/net/ethernet/intel/idpf/idpf_txrx.c
+++ b/drivers/net/ethernet/intel/idpf/idpf_txrx.c
@@ -4093,7 +4093,7 @@ static int idpf_vport_intr_req_irq(struct idpf_vport *vport,
 			continue;
 
 		name = kasprintf(GFP_KERNEL, "%s-%s-%s-%d", drv_name, if_name,
-				 vec_name, vidx);
+				 vec_name, vector);
 
 		err = request_irq(irq_num, idpf_vport_intr_clean_queues, 0,
 				  name, q_vector);
-- 
2.52.0.457.g6b5491de43-goog

Re: [Intel-wired-lan] [iwl-net PATCH v2] idpf: change IRQ naming to match netdev and ethtool queue numbering

Posted by Paul Menzel 3 hours ago

Dear Brian,


Thank you for your patch.

Am 26.01.26 um 15:46 schrieb Brian Vazquez via Intel-wired-lan:
> The code uses the vidx for the IRQ name but that doesn't match ethtool
> reporting or netdev naming, this makes it hard to tune the device and
> associate queues with IRQs. Sequentially requesting irqs starting from
> '0' makes the output consistent.
> 
> Before:
> 
> ethtool -L eth1 tx 1 combined 3
> 
> grep . /proc/irq/*/*idpf*/../smp_affinity_list
> /proc/irq/67/idpf-Mailbox-0/../smp_affinity_list:0-55,112-167
> /proc/irq/68/idpf-eth1-TxRx-1/../smp_affinity_list:0
> /proc/irq/70/idpf-eth1-TxRx-3/../smp_affinity_list:1
> /proc/irq/71/idpf-eth1-TxRx-4/../smp_affinity_list:2
> /proc/irq/72/idpf-eth1-Tx-5/../smp_affinity_list:3
> 
> ethtool -S eth1 | grep -v ': 0'
> NIC statistics:
>       tx_q-0_pkts: 1002
>       tx_q-1_pkts: 2679
>       tx_q-2_pkts: 1113
>       tx_q-3_pkts: 1192 <----- tx_q-3 vs idpf-eth1-Tx-5
>       rx_q-0_pkts: 1143
>       rx_q-1_pkts: 3172
>       rx_q-2_pkts: 1074
> 
> After:
> 
> ethtool -L eth1 tx 1 combined 3
> 
> grep . /proc/irq/*/*idpf*/../smp_affinity_list
> 
> /proc/irq/67/idpf-Mailbox-0/../smp_affinity_list:0-55,112-167
> /proc/irq/68/idpf-eth1-TxRx-0/../smp_affinity_list:0
> /proc/irq/70/idpf-eth1-TxRx-1/../smp_affinity_list:1
> /proc/irq/71/idpf-eth1-TxRx-2/../smp_affinity_list:2
> /proc/irq/72/idpf-eth1-Tx-3/../smp_affinity_list:3
> 
> ethtool -S eth1 | grep -v ': 0'
> NIC statistics:
>       tx_q-0_pkts: 118
>       tx_q-1_pkts: 134
>       tx_q-2_pkts: 228
>       tx_q-3_pkts: 138 <--- tx_q-3 matches idpf-eth1-Tx-3
>       rx_q-0_pkts: 111
>       rx_q-1_pkts: 366
>       rx_q-2_pkts: 120
> 
> Fixes: d4d558718266 ("idpf: initialize interrupts and enable vport")
> Signed-off-by: Brian Vazquez <brianvv@google.com>
> Reviewed-by: Brett Creeley <brett.creeley@amd.com>
> Reviewed-by: Aleksandr Loktionov <aleksandr.loktionov@intel.com>
> ---
> V2: Add mising Fixes tag
> 
>   drivers/net/ethernet/intel/idpf/idpf_txrx.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/net/ethernet/intel/idpf/idpf_txrx.c b/drivers/net/ethernet/intel/idpf/idpf_txrx.c
> index c2a1fe3c79ec..c1f8dfc570ce 100644
> --- a/drivers/net/ethernet/intel/idpf/idpf_txrx.c
> +++ b/drivers/net/ethernet/intel/idpf/idpf_txrx.c
> @@ -4093,7 +4093,7 @@ static int idpf_vport_intr_req_irq(struct idpf_vport *vport,
>   			continue;
>   
>   		name = kasprintf(GFP_KERNEL, "%s-%s-%s-%d", drv_name, if_name,
> -				 vec_name, vidx);
> +				 vec_name, vector);
>   
>   		err = request_irq(irq_num, idpf_vport_intr_clean_queues, 0,
>   				  name, q_vector);

With Andrew’s comment addressed in the commit message, this looks sensible.

Reviewed-by: Paul Menzel <pmenzel@molgen.mpg.de>


Kind regards,

Paul

Re: [iwl-net PATCH v2] idpf: change IRQ naming to match netdev and ethtool queue numbering

Posted by Andrew Lunn 4 hours ago

On Mon, Jan 26, 2026 at 02:46:24PM +0000, Brian Vazquez wrote:
> The code uses the vidx for the IRQ name but that doesn't match ethtool
> reporting or netdev naming, this makes it hard to tune the device and
> associate queues with IRQs. Sequentially requesting irqs starting from
> '0' makes the output consistent.
> 
> Before:
> 
> ethtool -L eth1 tx 1 combined 3
> 
> grep . /proc/irq/*/*idpf*/../smp_affinity_list
> /proc/irq/67/idpf-Mailbox-0/../smp_affinity_list:0-55,112-167
> /proc/irq/68/idpf-eth1-TxRx-1/../smp_affinity_list:0
> /proc/irq/70/idpf-eth1-TxRx-3/../smp_affinity_list:1
> /proc/irq/71/idpf-eth1-TxRx-4/../smp_affinity_list:2
> /proc/irq/72/idpf-eth1-Tx-5/../smp_affinity_list:3
> 
> ethtool -S eth1 | grep -v ': 0'
> NIC statistics:
>      tx_q-0_pkts: 1002
>      tx_q-1_pkts: 2679
>      tx_q-2_pkts: 1113
>      tx_q-3_pkts: 1192 <----- tx_q-3 vs idpf-eth1-Tx-5
>      rx_q-0_pkts: 1143
>      rx_q-1_pkts: 3172
>      rx_q-2_pkts: 1074
> 
> After:
> 
> ethtool -L eth1 tx 1 combined 3
> 
> grep . /proc/irq/*/*idpf*/../smp_affinity_list
> 
> /proc/irq/67/idpf-Mailbox-0/../smp_affinity_list:0-55,112-167
> /proc/irq/68/idpf-eth1-TxRx-0/../smp_affinity_list:0
> /proc/irq/70/idpf-eth1-TxRx-1/../smp_affinity_list:1
> /proc/irq/71/idpf-eth1-TxRx-2/../smp_affinity_list:2
> /proc/irq/72/idpf-eth1-Tx-3/../smp_affinity_list:3
> 
> ethtool -S eth1 | grep -v ': 0'
> NIC statistics:
>      tx_q-0_pkts: 118
>      tx_q-1_pkts: 134
>      tx_q-2_pkts: 228
>      tx_q-3_pkts: 138 <--- tx_q-3 matches idpf-eth1-Tx-3
>      rx_q-0_pkts: 111
>      rx_q-1_pkts: 366
>      rx_q-2_pkts: 120

Are there any ABI issues here?

   Andrew

Re: [iwl-net PATCH v2] idpf: change IRQ naming to match netdev and ethtool queue numbering

Posted by Brian Vazquez 3 hours ago

On Mon, Jan 26, 2026 at 11:24 AM Andrew Lunn <andrew@lunn.ch> wrote:
>
> On Mon, Jan 26, 2026 at 02:46:24PM +0000, Brian Vazquez wrote:
> > The code uses the vidx for the IRQ name but that doesn't match ethtool
> > reporting or netdev naming, this makes it hard to tune the device and
> > associate queues with IRQs. Sequentially requesting irqs starting from
> > '0' makes the output consistent.
> >
> > Before:
> >
> > ethtool -L eth1 tx 1 combined 3
> >
> > grep . /proc/irq/*/*idpf*/../smp_affinity_list
> > /proc/irq/67/idpf-Mailbox-0/../smp_affinity_list:0-55,112-167
> > /proc/irq/68/idpf-eth1-TxRx-1/../smp_affinity_list:0
> > /proc/irq/70/idpf-eth1-TxRx-3/../smp_affinity_list:1
> > /proc/irq/71/idpf-eth1-TxRx-4/../smp_affinity_list:2
> > /proc/irq/72/idpf-eth1-Tx-5/../smp_affinity_list:3
> >
> > ethtool -S eth1 | grep -v ': 0'
> > NIC statistics:
> >      tx_q-0_pkts: 1002
> >      tx_q-1_pkts: 2679
> >      tx_q-2_pkts: 1113
> >      tx_q-3_pkts: 1192 <----- tx_q-3 vs idpf-eth1-Tx-5
> >      rx_q-0_pkts: 1143
> >      rx_q-1_pkts: 3172
> >      rx_q-2_pkts: 1074
> >
> > After:
> >
> > ethtool -L eth1 tx 1 combined 3
> >
> > grep . /proc/irq/*/*idpf*/../smp_affinity_list
> >
> > /proc/irq/67/idpf-Mailbox-0/../smp_affinity_list:0-55,112-167
> > /proc/irq/68/idpf-eth1-TxRx-0/../smp_affinity_list:0
> > /proc/irq/70/idpf-eth1-TxRx-1/../smp_affinity_list:1
> > /proc/irq/71/idpf-eth1-TxRx-2/../smp_affinity_list:2
> > /proc/irq/72/idpf-eth1-Tx-3/../smp_affinity_list:3
> >
> > ethtool -S eth1 | grep -v ': 0'
> > NIC statistics:
> >      tx_q-0_pkts: 118
> >      tx_q-1_pkts: 134
> >      tx_q-2_pkts: 228
> >      tx_q-3_pkts: 138 <--- tx_q-3 matches idpf-eth1-Tx-3
> >      rx_q-0_pkts: 111
> >      rx_q-1_pkts: 366
> >      rx_q-2_pkts: 120
>
> Are there any ABI issues here?

The patch doesn't change the format, it just fixes the numbering in
the name to make it consistent with other reporting tools. It
shouldn't break any library.
>    Andrew

Re: [iwl-net PATCH v2] idpf: change IRQ naming to match netdev and ethtool queue numbering

Posted by Andrew Lunn 3 hours ago

On Mon, Jan 26, 2026 at 12:40:15PM -0500, Brian Vazquez wrote:
> On Mon, Jan 26, 2026 at 11:24 AM Andrew Lunn <andrew@lunn.ch> wrote:
> >
> > On Mon, Jan 26, 2026 at 02:46:24PM +0000, Brian Vazquez wrote:
> > > The code uses the vidx for the IRQ name but that doesn't match ethtool
> > > reporting or netdev naming, this makes it hard to tune the device and
> > > associate queues with IRQs. Sequentially requesting irqs starting from
> > > '0' makes the output consistent.
> > >
> > > Before:
> > >
> > > ethtool -L eth1 tx 1 combined 3
> > >
> > > grep . /proc/irq/*/*idpf*/../smp_affinity_list
> > > /proc/irq/67/idpf-Mailbox-0/../smp_affinity_list:0-55,112-167
> > > /proc/irq/68/idpf-eth1-TxRx-1/../smp_affinity_list:0
> > > /proc/irq/70/idpf-eth1-TxRx-3/../smp_affinity_list:1
> > > /proc/irq/71/idpf-eth1-TxRx-4/../smp_affinity_list:2
> > > /proc/irq/72/idpf-eth1-Tx-5/../smp_affinity_list:3
> > >
> > > ethtool -S eth1 | grep -v ': 0'
> > > NIC statistics:
> > >      tx_q-0_pkts: 1002
> > >      tx_q-1_pkts: 2679
> > >      tx_q-2_pkts: 1113
> > >      tx_q-3_pkts: 1192 <----- tx_q-3 vs idpf-eth1-Tx-5
> > >      rx_q-0_pkts: 1143
> > >      rx_q-1_pkts: 3172
> > >      rx_q-2_pkts: 1074
> > >
> > > After:
> > >
> > > ethtool -L eth1 tx 1 combined 3
> > >
> > > grep . /proc/irq/*/*idpf*/../smp_affinity_list
> > >
> > > /proc/irq/67/idpf-Mailbox-0/../smp_affinity_list:0-55,112-167
> > > /proc/irq/68/idpf-eth1-TxRx-0/../smp_affinity_list:0
> > > /proc/irq/70/idpf-eth1-TxRx-1/../smp_affinity_list:1
> > > /proc/irq/71/idpf-eth1-TxRx-2/../smp_affinity_list:2
> > > /proc/irq/72/idpf-eth1-Tx-3/../smp_affinity_list:3
> > >
> > > ethtool -S eth1 | grep -v ': 0'
> > > NIC statistics:
> > >      tx_q-0_pkts: 118
> > >      tx_q-1_pkts: 134
> > >      tx_q-2_pkts: 228
> > >      tx_q-3_pkts: 138 <--- tx_q-3 matches idpf-eth1-Tx-3
> > >      rx_q-0_pkts: 111
> > >      rx_q-1_pkts: 366
> > >      rx_q-2_pkts: 120
> >
> > Are there any ABI issues here?
> 
> The patch doesn't change the format, it just fixes the numbering in
> the name to make it consistent with other reporting tools. It
> shouldn't break any library.

But is the numbering part of the ABI?

Making a comment about ABI in the commit message makes it clear it is
something you have considered, and you have decided it is not an
issue. If there is no such comment, reviewers probably should ask.

       Andrew

Re: [Intel-wired-lan] [iwl-net PATCH v2] idpf: change IRQ naming to match netdev and ethtool queue numbering

Posted by Jacob Keller 31 minutes ago


On 1/26/2026 9:53 AM, Andrew Lunn wrote:
> On Mon, Jan 26, 2026 at 12:40:15PM -0500, Brian Vazquez wrote:
>> On Mon, Jan 26, 2026 at 11:24 AM Andrew Lunn <andrew@lunn.ch> wrote:
>>>
>>> On Mon, Jan 26, 2026 at 02:46:24PM +0000, Brian Vazquez wrote:
>>>> The code uses the vidx for the IRQ name but that doesn't match ethtool
>>>> reporting or netdev naming, this makes it hard to tune the device and
>>>> associate queues with IRQs. Sequentially requesting irqs starting from
>>>> '0' makes the output consistent.
>>>>
>>>> Before:
>>>>
>>>> ethtool -L eth1 tx 1 combined 3
>>>>
>>>> grep . /proc/irq/*/*idpf*/../smp_affinity_list
>>>> /proc/irq/67/idpf-Mailbox-0/../smp_affinity_list:0-55,112-167
>>>> /proc/irq/68/idpf-eth1-TxRx-1/../smp_affinity_list:0
>>>> /proc/irq/70/idpf-eth1-TxRx-3/../smp_affinity_list:1
>>>> /proc/irq/71/idpf-eth1-TxRx-4/../smp_affinity_list:2
>>>> /proc/irq/72/idpf-eth1-Tx-5/../smp_affinity_list:3
>>>>
>>>> ethtool -S eth1 | grep -v ': 0'
>>>> NIC statistics:
>>>>       tx_q-0_pkts: 1002
>>>>       tx_q-1_pkts: 2679
>>>>       tx_q-2_pkts: 1113
>>>>       tx_q-3_pkts: 1192 <----- tx_q-3 vs idpf-eth1-Tx-5
>>>>       rx_q-0_pkts: 1143
>>>>       rx_q-1_pkts: 3172
>>>>       rx_q-2_pkts: 1074
>>>>
>>>> After:
>>>>
>>>> ethtool -L eth1 tx 1 combined 3
>>>>
>>>> grep . /proc/irq/*/*idpf*/../smp_affinity_list
>>>>
>>>> /proc/irq/67/idpf-Mailbox-0/../smp_affinity_list:0-55,112-167
>>>> /proc/irq/68/idpf-eth1-TxRx-0/../smp_affinity_list:0
>>>> /proc/irq/70/idpf-eth1-TxRx-1/../smp_affinity_list:1
>>>> /proc/irq/71/idpf-eth1-TxRx-2/../smp_affinity_list:2
>>>> /proc/irq/72/idpf-eth1-Tx-3/../smp_affinity_list:3
>>>>
>>>> ethtool -S eth1 | grep -v ': 0'
>>>> NIC statistics:
>>>>       tx_q-0_pkts: 118
>>>>       tx_q-1_pkts: 134
>>>>       tx_q-2_pkts: 228
>>>>       tx_q-3_pkts: 138 <--- tx_q-3 matches idpf-eth1-Tx-3
>>>>       rx_q-0_pkts: 111
>>>>       rx_q-1_pkts: 366
>>>>       rx_q-2_pkts: 120
>>>
>>> Are there any ABI issues here?
>>
>> The patch doesn't change the format, it just fixes the numbering in
>> the name to make it consistent with other reporting tools. It
>> shouldn't break any library.
> 
> But is the numbering part of the ABI?
> 
> Making a comment about ABI in the commit message makes it clear it is
> something you have considered, and you have decided it is not an
> issue. If there is no such comment, reviewers probably should ask.
> 
>         Andrew

I don't see how an application can depend on the name if it can't 
correlate it to anything meaningful. The change fixes the ID values used 
so that they *do* correlate. If an application was previously assuming 
it correlated to the queue ID, it would incorrect associate the IRQ with 
the wrong queue.

Re: [Intel-wired-lan] [iwl-net PATCH v2] idpf: change IRQ naming to match netdev and ethtool queue numbering

Posted by Eric Dumazet 26 minutes ago

On Mon, Jan 26, 2026 at 9:46 PM Jacob Keller <jacob.e.keller@intel.com> wrote:
>
>
>
> On 1/26/2026 9:53 AM, Andrew Lunn wrote:
> > On Mon, Jan 26, 2026 at 12:40:15PM -0500, Brian Vazquez wrote:
> >> On Mon, Jan 26, 2026 at 11:24 AM Andrew Lunn <andrew@lunn.ch> wrote:
> >>>
> >>> On Mon, Jan 26, 2026 at 02:46:24PM +0000, Brian Vazquez wrote:
> >>>> The code uses the vidx for the IRQ name but that doesn't match ethtool
> >>>> reporting or netdev naming, this makes it hard to tune the device and
> >>>> associate queues with IRQs. Sequentially requesting irqs starting from
> >>>> '0' makes the output consistent.
> >>>>
> >>>> Before:
> >>>>
> >>>> ethtool -L eth1 tx 1 combined 3
> >>>>
> >>>> grep . /proc/irq/*/*idpf*/../smp_affinity_list
> >>>> /proc/irq/67/idpf-Mailbox-0/../smp_affinity_list:0-55,112-167
> >>>> /proc/irq/68/idpf-eth1-TxRx-1/../smp_affinity_list:0
> >>>> /proc/irq/70/idpf-eth1-TxRx-3/../smp_affinity_list:1
> >>>> /proc/irq/71/idpf-eth1-TxRx-4/../smp_affinity_list:2
> >>>> /proc/irq/72/idpf-eth1-Tx-5/../smp_affinity_list:3
> >>>>
> >>>> ethtool -S eth1 | grep -v ': 0'
> >>>> NIC statistics:
> >>>>       tx_q-0_pkts: 1002
> >>>>       tx_q-1_pkts: 2679
> >>>>       tx_q-2_pkts: 1113
> >>>>       tx_q-3_pkts: 1192 <----- tx_q-3 vs idpf-eth1-Tx-5
> >>>>       rx_q-0_pkts: 1143
> >>>>       rx_q-1_pkts: 3172
> >>>>       rx_q-2_pkts: 1074
> >>>>
> >>>> After:
> >>>>
> >>>> ethtool -L eth1 tx 1 combined 3
> >>>>
> >>>> grep . /proc/irq/*/*idpf*/../smp_affinity_list
> >>>>
> >>>> /proc/irq/67/idpf-Mailbox-0/../smp_affinity_list:0-55,112-167
> >>>> /proc/irq/68/idpf-eth1-TxRx-0/../smp_affinity_list:0
> >>>> /proc/irq/70/idpf-eth1-TxRx-1/../smp_affinity_list:1
> >>>> /proc/irq/71/idpf-eth1-TxRx-2/../smp_affinity_list:2
> >>>> /proc/irq/72/idpf-eth1-Tx-3/../smp_affinity_list:3
> >>>>
> >>>> ethtool -S eth1 | grep -v ': 0'
> >>>> NIC statistics:
> >>>>       tx_q-0_pkts: 118
> >>>>       tx_q-1_pkts: 134
> >>>>       tx_q-2_pkts: 228
> >>>>       tx_q-3_pkts: 138 <--- tx_q-3 matches idpf-eth1-Tx-3
> >>>>       rx_q-0_pkts: 111
> >>>>       rx_q-1_pkts: 366
> >>>>       rx_q-2_pkts: 120
> >>>
> >>> Are there any ABI issues here?
> >>
> >> The patch doesn't change the format, it just fixes the numbering in
> >> the name to make it consistent with other reporting tools. It
> >> shouldn't break any library.
> >
> > But is the numbering part of the ABI?
> >
> > Making a comment about ABI in the commit message makes it clear it is
> > something you have considered, and you have decided it is not an
> > issue. If there is no such comment, reviewers probably should ask.
> >
> >         Andrew
>
> I don't see how an application can depend on the name if it can't
> correlate it to anything meaningful. The change fixes the ID values used
> so that they *do* correlate. If an application was previously assuming
> it correlated to the queue ID, it would incorrect associate the IRQ with
> the wrong queue.

Agree, this mismatch caused me some surprises, we can not keep a broken
ABI (which has been broken by accident)

Re: [Intel-wired-lan] [iwl-net PATCH v2] idpf: change IRQ naming to match netdev and ethtool queue numbering

Posted by Andrew Lunn 5 minutes ago

On Mon, Jan 26, 2026 at 09:51:10PM +0100, Eric Dumazet wrote:
> On Mon, Jan 26, 2026 at 9:46 PM Jacob Keller <jacob.e.keller@intel.com> wrote:
> >
> >
> >
> > On 1/26/2026 9:53 AM, Andrew Lunn wrote:
> > > On Mon, Jan 26, 2026 at 12:40:15PM -0500, Brian Vazquez wrote:
> > >> On Mon, Jan 26, 2026 at 11:24 AM Andrew Lunn <andrew@lunn.ch> wrote:
> > >>>
> > >>> On Mon, Jan 26, 2026 at 02:46:24PM +0000, Brian Vazquez wrote:
> > >>>> The code uses the vidx for the IRQ name but that doesn't match ethtool
> > >>>> reporting or netdev naming, this makes it hard to tune the device and
> > >>>> associate queues with IRQs. Sequentially requesting irqs starting from
> > >>>> '0' makes the output consistent.
> > >>>>
> > >>>> Before:
> > >>>>
> > >>>> ethtool -L eth1 tx 1 combined 3
> > >>>>
> > >>>> grep . /proc/irq/*/*idpf*/../smp_affinity_list
> > >>>> /proc/irq/67/idpf-Mailbox-0/../smp_affinity_list:0-55,112-167
> > >>>> /proc/irq/68/idpf-eth1-TxRx-1/../smp_affinity_list:0
> > >>>> /proc/irq/70/idpf-eth1-TxRx-3/../smp_affinity_list:1
> > >>>> /proc/irq/71/idpf-eth1-TxRx-4/../smp_affinity_list:2
> > >>>> /proc/irq/72/idpf-eth1-Tx-5/../smp_affinity_list:3
> > >>>>
> > >>>> ethtool -S eth1 | grep -v ': 0'
> > >>>> NIC statistics:
> > >>>>       tx_q-0_pkts: 1002
> > >>>>       tx_q-1_pkts: 2679
> > >>>>       tx_q-2_pkts: 1113
> > >>>>       tx_q-3_pkts: 1192 <----- tx_q-3 vs idpf-eth1-Tx-5
> > >>>>       rx_q-0_pkts: 1143
> > >>>>       rx_q-1_pkts: 3172
> > >>>>       rx_q-2_pkts: 1074
> > >>>>
> > >>>> After:
> > >>>>
> > >>>> ethtool -L eth1 tx 1 combined 3
> > >>>>
> > >>>> grep . /proc/irq/*/*idpf*/../smp_affinity_list
> > >>>>
> > >>>> /proc/irq/67/idpf-Mailbox-0/../smp_affinity_list:0-55,112-167
> > >>>> /proc/irq/68/idpf-eth1-TxRx-0/../smp_affinity_list:0
> > >>>> /proc/irq/70/idpf-eth1-TxRx-1/../smp_affinity_list:1
> > >>>> /proc/irq/71/idpf-eth1-TxRx-2/../smp_affinity_list:2
> > >>>> /proc/irq/72/idpf-eth1-Tx-3/../smp_affinity_list:3
> > >>>>
> > >>>> ethtool -S eth1 | grep -v ': 0'
> > >>>> NIC statistics:
> > >>>>       tx_q-0_pkts: 118
> > >>>>       tx_q-1_pkts: 134
> > >>>>       tx_q-2_pkts: 228
> > >>>>       tx_q-3_pkts: 138 <--- tx_q-3 matches idpf-eth1-Tx-3
> > >>>>       rx_q-0_pkts: 111
> > >>>>       rx_q-1_pkts: 366
> > >>>>       rx_q-2_pkts: 120
> > >>>
> > >>> Are there any ABI issues here?
> > >>
> > >> The patch doesn't change the format, it just fixes the numbering in
> > >> the name to make it consistent with other reporting tools. It
> > >> shouldn't break any library.
> > >
> > > But is the numbering part of the ABI?
> > >
> > > Making a comment about ABI in the commit message makes it clear it is
> > > something you have considered, and you have decided it is not an
> > > issue. If there is no such comment, reviewers probably should ask.
> > >
> > >         Andrew
> >
> > I don't see how an application can depend on the name if it can't
> > correlate it to anything meaningful. The change fixes the ID values used
> > so that they *do* correlate. If an application was previously assuming
> > it correlated to the queue ID, it would incorrect associate the IRQ with
> > the wrong queue.
> 
> Agree, this mismatch caused me some surprises, we can not keep a broken
> ABI (which has been broken by accident)

So everybody is agreed, great. I just think it would of been good to
mention ABI in the commit message, to show due diligence has been
done.

   Andrew