[PATCH net-next-2.6 1/2] be2net: Adding an option to use INTx instead of MSI-X

[PATCH net-next-2.6 1/2] be2net: Adding an option to use INTx instead of MSI-X

[Somnath Kotur]

By default, be2net uses MSIx wherever possible.
Adding a module parameter to use INTx for users who do not want to use MSIx.

Signed-off-by: Somnath Kotur <somnath.kotur@emulex.com>
---
 drivers/net/benet/be_main.c |   12 +++++++++++-
 1 files changed, 11 insertions(+), 1 deletions(-)

diff --git a/drivers/net/benet/be_main.c b/drivers/net/benet/be_main.c
index 45b1f66..1262292 100644
--- a/drivers/net/benet/be_main.c
+++ b/drivers/net/benet/be_main.c
@@ -27,10 +27,13 @@ MODULE_LICENSE("GPL");
 
 static unsigned int rx_frag_size = 2048;
 static unsigned int num_vfs;
+static unsigned int msix = 1;
 module_param(rx_frag_size, uint, S_IRUGO);
 module_param(num_vfs, uint, S_IRUGO);
+module_param(msix, uint, S_IRUGO);
 MODULE_PARM_DESC(rx_frag_size, "Size of a fragment that holds rcvd data.");
 MODULE_PARM_DESC(num_vfs, "Number of PCI VFs to initialize");
+MODULE_PARM_DESC(msix, "Enable/Disable the MSIx (MSIx enabled by default)");
 
 static bool multi_rxq = true;
 module_param(multi_rxq, bool, S_IRUGO | S_IWUSR);
@@ -2856,7 +2859,8 @@ static int __devinit be_probe(struct pci_dev *pdev,
 	if (status)
 		goto stats_clean;
 
-	be_msix_enable(adapter);
+	if (msix)
+		be_msix_enable(adapter);
 
 	INIT_DELAYED_WORK(&adapter->work, be_worker);
 
@@ -3082,6 +3086,12 @@ static int __init be_init_module(void)
 		num_vfs = 32;
 	}
 
+	if (!msix && num_vfs > 0) {
+		printk(KERN_WARNING DRV_NAME
+			" : MSIx required for num_vfs > 0. Ignoring msix=0\n");
+		msix = 1;
+	}
+
 	return pci_register_driver(&be_driver);
 }
 module_init(be_init_module);
-- 
1.5.6.1

Re: [PATCH net-next-2.6 1/2] be2net: Adding an option to use INTx instead of MSI-X

[David Miller]

From: Somnath Kotur <somnath.kotur@emulex.com>
Date: Mon, 25 Oct 2010 16:42:35 +0530

> By default, be2net uses MSIx wherever possible.
> Adding a module parameter to use INTx for users who do not want to use MSIx.
> 
> Signed-off-by: Somnath Kotur <somnath.kotur@emulex.com>

Either add a new ethtool flag, or use the PCI subsystem facilities
for tweaking things to implement this.

Do not use a module option, otherwise every other networking driver
author will get the same "cool" idea, give the module option
different names, and the resulting user experience is terrible.

Re: [PATCH net-next-2.6 1/2] be2net: Adding an option to use INTx instead of MSI-X

[Ben Hutchings]

David Miller wrote:
> From: Somnath Kotur <somnath.kotur@emulex.com>
> Date: Mon, 25 Oct 2010 16:42:35 +0530
> 
> > By default, be2net uses MSIx wherever possible.
> > Adding a module parameter to use INTx for users who do not want to use MSIx.
> > 
> > Signed-off-by: Somnath Kotur <somnath.kotur@emulex.com>
> 
> Either add a new ethtool flag, or use the PCI subsystem facilities
> for tweaking things to implement this.
>
> Do not use a module option, otherwise every other networking driver
> author will get the same "cool" idea, give the module option
> different names, and the resulting user experience is terrible.

This has already happened, sadly.  So far as I can see it's mostly done
to allow users to work around systems with broken MSIs; I'm not aware of
any other reason to prefer legacy interrupts.  However, the PCI subsystem
already implements a blacklist and a kernel parameter for disabling MSIs
on these systems.

Ben.

-- 
Ben Hutchings, Senior Software Engineer, Solarflare Communications
Not speaking for my employer; that's the marketing department's job.
They asked us to note that Solarflare product names are trademarked.

Re: [PATCH net-next-2.6 1/2] be2net: Adding an option to use INTx instead of MSI-X

[David Miller]

From: Ben Hutchings <bhutchings@solarflare.com>
Date: Mon, 25 Oct 2010 23:38:53 +0100

> David Miller wrote:
>> From: Somnath Kotur <somnath.kotur@emulex.com>
>> Date: Mon, 25 Oct 2010 16:42:35 +0530
>> 
>> > By default, be2net uses MSIx wherever possible.
>> > Adding a module parameter to use INTx for users who do not want to use MSIx.
>> > 
>> > Signed-off-by: Somnath Kotur <somnath.kotur@emulex.com>
>> 
>> Either add a new ethtool flag, or use the PCI subsystem facilities
>> for tweaking things to implement this.
>>
>> Do not use a module option, otherwise every other networking driver
>> author will get the same "cool" idea, give the module option
>> different names, and the resulting user experience is terrible.
> 
> This has already happened, sadly.  So far as I can see it's mostly done
> to allow users to work around systems with broken MSIs; I'm not aware of
> any other reason to prefer legacy interrupts.  However, the PCI subsystem
> already implements a blacklist and a kernel parameter for disabling MSIs
> on these systems.

The PCI subsystem bits I'm totally fine with.

But in the drivers themselves, that's what I don't want.

RE: [PATCH net-next-2.6 1/2] be2net: Adding an option to use INTx instead of MSI-X

[Somnath.Kotur]

Dave,
         Could you pls ignore this patch and apply the next patch in the series ?
 ( PATCH 2/2]  be2net: Schedule/Destroy worker thread in probe()/remove() rather than open()/close()

Thanks
Som
________________________________________
From: David Miller [davem@davemloft.net]
Sent: Tuesday, October 26, 2010 4:55 AM
To: bhutchings@solarflare.com
Cc: Kotur, Somnath; netdev@vger.kernel.org; linux-pci@vger.kernel.org
Subject: Re: [PATCH net-next-2.6 1/2] be2net: Adding an option to use INTx instead of MSI-X

From: Ben Hutchings <bhutchings@solarflare.com>
Date: Mon, 25 Oct 2010 23:38:53 +0100

> David Miller wrote:
>> From: Somnath Kotur <somnath.kotur@emulex.com>
>> Date: Mon, 25 Oct 2010 16:42:35 +0530
>>
>> > By default, be2net uses MSIx wherever possible.
>> > Adding a module parameter to use INTx for users who do not want to use MSIx.
>> >
>> > Signed-off-by: Somnath Kotur <somnath.kotur@emulex.com>
>>
>> Either add a new ethtool flag, or use the PCI subsystem facilities
>> for tweaking things to implement this.
>>
>> Do not use a module option, otherwise every other networking driver
>> author will get the same "cool" idea, give the module option
>> different names, and the resulting user experience is terrible.
>
> This has already happened, sadly.  So far as I can see it's mostly done
> to allow users to work around systems with broken MSIs; I'm not aware of
> any other reason to prefer legacy interrupts.  However, the PCI subsystem
> already implements a blacklist and a kernel parameter for disabling MSIs
> on these systems.

The PCI subsystem bits I'm totally fine with.

But in the drivers themselves, that's what I don't want.

Re: [PATCH net-next-2.6 1/2] be2net: Adding an option to use INTx instead of MSI-X

[Michael Ellerman]

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On Mon, 2010-10-25 at 16:25 -0700, David Miller wrote:
> From: Ben Hutchings <bhutchings@solarflare.com>
> Date: Mon, 25 Oct 2010 23:38:53 +0100
> 
> > David Miller wrote:
> >> From: Somnath Kotur <somnath.kotur@emulex.com>
> >> Date: Mon, 25 Oct 2010 16:42:35 +0530
> >> 
> >> > By default, be2net uses MSIx wherever possible.
> >> > Adding a module parameter to use INTx for users who do not want to use MSIx.
> >> > 
> >> > Signed-off-by: Somnath Kotur <somnath.kotur@emulex.com>
> >> 
> >> Either add a new ethtool flag, or use the PCI subsystem facilities
> >> for tweaking things to implement this.
> >>
> >> Do not use a module option, otherwise every other networking driver
> >> author will get the same "cool" idea, give the module option
> >> different names, and the resulting user experience is terrible.
> > 
> > This has already happened, sadly.  So far as I can see it's mostly done
> > to allow users to work around systems with broken MSIs; I'm not aware of
> > any other reason to prefer legacy interrupts.  However, the PCI subsystem
> > already implements a blacklist and a kernel parameter for disabling MSIs
> > on these systems.
> 
> The PCI subsystem bits I'm totally fine with.
> 
> But in the drivers themselves, that's what I don't want.

That horse has really really bolted, it's gawn.

I count 26 drivers with "disable MSI/X" parameters. Some even have more
than one.

11 of them are network drivers, 9 scsi, 3 ata.

I agree it's a mess for users, but it's probably preferable to a
non-working driver.

Ethtool would be nice, but only for network drivers. Is there a generic
solution, quirks are obviously not keeping people happy.

cheers



MSI:

Param "msi", 10 users:
  drivers/ata/sata_mv.c:MODULE_PARM_DESC(msi, "Enable use of PCI MSI (0=off, 1=on)");
  drivers/ata/sata_nv.c:MODULE_PARM_DESC(msi, "Enable use of MSI (Default: false)");
  drivers/ata/sata_sil24.c:MODULE_PARM_DESC(msi, "Enable MSI (Default: false)");
  drivers/net/cxgb3/cxgb3_main.c:MODULE_PARM_DESC(msi, "whether to use MSI or MSI-X");
  drivers/net/cxgb4/cxgb4_main.c:MODULE_PARM_DESC(msi, "whether to use INTx (0), MSI (1) or MSI-X (2)");
  drivers/net/cxgb4vf/cxgb4vf_main.c:MODULE_PARM_DESC(msi, "whether to use MSI-X or MSI");
  drivers/net/forcedeth.c:MODULE_PARM_DESC(msi, "MSI interrupts are enabled by setting to 1 and disabled by setting to 0.");
  drivers/net/qla3xxx.c:MODULE_PARM_DESC(msi, "Turn on Message Signaled Interrupts.");
  drivers/scsi/aacraid/aachba.c:MODULE_PARM_DESC(msi, "IRQ handling."
  drivers/scsi/stex.c:MODULE_PARM_DESC(msi, "Enable Message Signaled Interrupts(0=off, 1=on)");

Param "use_msi", 4 users:
  drivers/net/qlcnic/qlcnic_main.c:MODULE_PARM_DESC(use_msi, "MSI interrupt (0=disabled, 1=enabled");
  drivers/scsi/3w-9xxx.c:MODULE_PARM_DESC(use_msi, "Use Message Signaled Interrupts.  Default: 0");
  drivers/scsi/3w-sas.c:MODULE_PARM_DESC(use_msi, "Use Message Signaled Interrupts. Default: 0");
  drivers/scsi/aic94xx/aic94xx_init.c:MODULE_PARM_DESC(use_msi, "\n"

Param "disable_msi", 4 users:
  drivers/scsi/vmw_pvscsi.c:MODULE_PARM_DESC(disable_msi, "Disable MSI use in driver - (default=0)");
  drivers/net/bnx2.c:MODULE_PARM_DESC(disable_msi, "Disable Message Signaled Interrupt (MSI)");
  drivers/net/chelsio/cxgb2.c:MODULE_PARM_DESC(disable_msi, "Disable Message Signaled Interrupt (MSI)");
  drivers/net/sky2.c:MODULE_PARM_DESC(disable_msi, "Disable Message Signaled Interrupt (MSI)");

Misc:
  sound/pci/hda/hda_intel.c:MODULE_PARM_DESC(enable_msi, "Enable Message Signaled Interrupt (MSI)");
  drivers/message/fusion/mptbase.c:MODULE_PARM_DESC(mpt_msi_enable_spi, " Enable MSI Support for SPI \
  drivers/message/fusion/mptbase.c:MODULE_PARM_DESC(mpt_msi_enable_fc, " Enable MSI Support for FC \
  drivers/message/fusion/mptbase.c:MODULE_PARM_DESC(mpt_msi_enable_sas, " Enable MSI Support for SAS \
  drivers/net/myri10ge/myri10ge.c:MODULE_PARM_DESC(myri10ge_msi, "Enable Message Signalled Interrupts");


MSI-X:

Param "msi_x", 2 users:
  drivers/infiniband/hw/mthca/mthca_main.c:MODULE_PARM_DESC(msi_x, "attempt to use MSI-X if nonzero");
  drivers/net/mlx4/main.c:MODULE_PARM_DESC(msi_x, "attempt to use MSI-X if nonzero");

Misc:
  drivers/net/forcedeth.c:MODULE_PARM_DESC(msix, "MSIX interrupts are enabled by setting to 1 and disabled by setting to 0.");
  drivers/net/qlcnic/qlcnic_main.c:MODULE_PARM_DESC(use_msi_x, "MSI-X interrupt (0=disabled, 1=enabled");
  drivers/scsi/bfa/bfad_intr.c:MODULE_PARM_DESC(msix_disable_cb, "Disable MSIX for Brocade-415/425/815/825"
  drivers/scsi/bfa/bfad_intr.c:MODULE_PARM_DESC(msix_disable_ct, "Disable MSIX for Brocade-1010/1020/804"
  drivers/scsi/mpt2sas/mpt2sas_base.c:MODULE_PARM_DESC(msix_disable, " disable msix routed interrupts (default=0)");
  drivers/scsi/qla4xxx/ql4_os.c:MODULE_PARM_DESC(ql4xenablemsix,
  drivers/scsi/vmw_pvscsi.c:MODULE_PARM_DESC(disable_msix, "Disable MSI-X use in driver - (default=0)");


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Re: [PATCH net-next-2.6 1/2] be2net: Adding an option to use INTx instead of MSI-X

[Ben Hutchings]

Michael Ellerman wrote:
> On Mon, 2010-10-25 at 16:25 -0700, David Miller wrote:
> > From: Ben Hutchings <bhutchings@solarflare.com>
> > Date: Mon, 25 Oct 2010 23:38:53 +0100
> > 
> > > David Miller wrote:
> > >> From: Somnath Kotur <somnath.kotur@emulex.com>
> > >> Date: Mon, 25 Oct 2010 16:42:35 +0530
> > >> 
> > >> > By default, be2net uses MSIx wherever possible.
> > >> > Adding a module parameter to use INTx for users who do not want to use MSIx.
> > >> > 
> > >> > Signed-off-by: Somnath Kotur <somnath.kotur@emulex.com>
> > >> 
> > >> Either add a new ethtool flag, or use the PCI subsystem facilities
> > >> for tweaking things to implement this.
> > >>
> > >> Do not use a module option, otherwise every other networking driver
> > >> author will get the same "cool" idea, give the module option
> > >> different names, and the resulting user experience is terrible.
> > > 
> > > This has already happened, sadly.  So far as I can see it's mostly done
> > > to allow users to work around systems with broken MSIs; I'm not aware of
> > > any other reason to prefer legacy interrupts.  However, the PCI subsystem
> > > already implements a blacklist and a kernel parameter for disabling MSIs
> > > on these systems.
> > 
> > The PCI subsystem bits I'm totally fine with.
> > 
> > But in the drivers themselves, that's what I don't want.
> 
> That horse has really really bolted, it's gawn.
> 
> I count 26 drivers with "disable MSI/X" parameters. Some even have more
> than one.
> 
> 11 of them are network drivers, 9 scsi, 3 ata.
> 
> I agree it's a mess for users, but it's probably preferable to a
> non-working driver.
> 
> Ethtool would be nice, but only for network drivers. Is there a generic
> solution, quirks are obviously not keeping people happy.
 
Since this is (normally) a property of the system, pci=nomsi is the
generic solution.

[...]
> Misc:
>   sound/pci/hda/hda_intel.c:MODULE_PARM_DESC(enable_msi, "Enable Message Signaled Interrupt (MSI)");
>   drivers/message/fusion/mptbase.c:MODULE_PARM_DESC(mpt_msi_enable_spi, " Enable MSI Support for SPI \
>   drivers/message/fusion/mptbase.c:MODULE_PARM_DESC(mpt_msi_enable_fc, " Enable MSI Support for FC \
>   drivers/message/fusion/mptbase.c:MODULE_PARM_DESC(mpt_msi_enable_sas, " Enable MSI Support for SAS \
>   drivers/net/myri10ge/myri10ge.c:MODULE_PARM_DESC(myri10ge_msi, "Enable Message Signalled Interrupts");
[...]

  drivers/net/sfc/efx.c:MODULE_PARM_DESC(interrupt_mode,
  drivers/net/sfc/efx.c-                 "Interrupt mode (0=>MSIX 1=>MSI 2=>legacy)");

Ben.

-- 
Ben Hutchings, Senior Software Engineer, Solarflare Communications
Not speaking for my employer; that's the marketing department's job.
They asked us to note that Solarflare product names are trademarked.

Re: [PATCH net-next-2.6 1/2] be2net: Adding an option to use INTx instead of MSI-X

[Michael Ellerman]

[-- Attachment #1: Type: text/plain, Size: 1394 bytes --]

On Tue, 2010-10-26 at 14:32 +0100, Ben Hutchings wrote:
> Michael Ellerman wrote:
> > On Mon, 2010-10-25 at 16:25 -0700, David Miller wrote:
> > > From: Ben Hutchings <bhutchings@solarflare.com>
> > > Date: Mon, 25 Oct 2010 23:38:53 +0100

> > Ethtool would be nice, but only for network drivers. Is there a generic
> > solution, quirks are obviously not keeping people happy.
>  
> Since this is (normally) a property of the system, pci=nomsi is the
> generic solution.

Sort of, it's a big hammer. Did all these driver writers not know about
pci=nomsi or did they prefer to add a parameter to their driver for some
reason?

> [...]
> > Misc:
> >   sound/pci/hda/hda_intel.c:MODULE_PARM_DESC(enable_msi, "Enable Message Signaled Interrupt (MSI)");
> >   drivers/message/fusion/mptbase.c:MODULE_PARM_DESC(mpt_msi_enable_spi, " Enable MSI Support for SPI \
> >   drivers/message/fusion/mptbase.c:MODULE_PARM_DESC(mpt_msi_enable_fc, " Enable MSI Support for FC \
> >   drivers/message/fusion/mptbase.c:MODULE_PARM_DESC(mpt_msi_enable_sas, " Enable MSI Support for SAS \
> >   drivers/net/myri10ge/myri10ge.c:MODULE_PARM_DESC(myri10ge_msi, "Enable Message Signalled Interrupts");
> [...]
> 
>   drivers/net/sfc/efx.c:MODULE_PARM_DESC(interrupt_mode,
>   drivers/net/sfc/efx.c-                 "Interrupt mode (0=>MSIX 1=>MSI 2=>legacy)");

Well spotted.

cheers



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Re: [PATCH net-next-2.6 1/2] be2net: Adding an option to use INTx instead of MSI-X

[David Miller]

From: Michael Ellerman <michael@ellerman.id.au>
Date: Tue, 26 Oct 2010 17:52:08 +1100

> That horse has really really bolted, it's gawn.
> 
> I count 26 drivers with "disable MSI/X" parameters. Some even have more
> than one.
> 
> 11 of them are network drivers, 9 scsi, 3 ata.
> 
> I agree it's a mess for users, but it's probably preferable to a
> non-working driver.

Stupid inappropriate things being in the tree doesn't mean I need
to accept more of them.

Re: [PATCH net-next-2.6 1/2] be2net: Adding an option to use INTx instead of MSI-X

[David Miller]

From: Michael Ellerman <michael@ellerman.id.au>
Date: Wed, 27 Oct 2010 10:20:35 +1100

> On Tue, 2010-10-26 at 14:32 +0100, Ben Hutchings wrote:
>> Michael Ellerman wrote:
>> > On Mon, 2010-10-25 at 16:25 -0700, David Miller wrote:
>> > > From: Ben Hutchings <bhutchings@solarflare.com>
>> > > Date: Mon, 25 Oct 2010 23:38:53 +0100
> 
>> > Ethtool would be nice, but only for network drivers. Is there a generic
>> > solution, quirks are obviously not keeping people happy.
>>  
>> Since this is (normally) a property of the system, pci=nomsi is the
>> generic solution.
> 
> Sort of, it's a big hammer. Did all these driver writers not know about
> pci=nomsi or did they prefer to add a parameter to their driver for some
> reason?

Every time I've actually done the work to try and track down the
true issue, it always turned out to be a PCI chipset problem rather
than a device specific issue.

Re: [PATCH net-next-2.6 1/2] be2net: Adding an option to use INTx instead of MSI-X

[Grant Grundler]

On Wed, Oct 27, 2010 at 08:46:04AM -0700, David Miller wrote:
> From: Michael Ellerman <michael@ellerman.id.au>
> Date: Wed, 27 Oct 2010 10:20:35 +1100
> 
> > On Tue, 2010-10-26 at 14:32 +0100, Ben Hutchings wrote:
> >> Michael Ellerman wrote:
> >> > On Mon, 2010-10-25 at 16:25 -0700, David Miller wrote:
> >> > > From: Ben Hutchings <bhutchings@solarflare.com>
> >> > > Date: Mon, 25 Oct 2010 23:38:53 +0100
> > 
> >> > Ethtool would be nice, but only for network drivers. Is there a generic
> >> > solution, quirks are obviously not keeping people happy.
> >>  
> >> Since this is (normally) a property of the system, pci=nomsi is the
> >> generic solution.
> > 
> > Sort of, it's a big hammer. Did all these driver writers not know about
> > pci=nomsi or did they prefer to add a parameter to their driver for some
> > reason?
> 
> Every time I've actually done the work to try and track down the
> true issue, it always turned out to be a PCI chipset problem rather
> than a device specific issue.

I agree with your generalization. I can think of only one exception:
ISTR pre-5705 tg3 chips would send both MSI and assert IRQ line at the same time.

My guess is driver writers just want knob to "work around" any issues
*their* driver might see with chipset. Disabling MSI for all drivers
doesn't leave opportunity for experimenting with individual drivers.

hth,
grant

> --
> To unsubscribe from this list: send the line "unsubscribe linux-pci" in
> the body of a message to majordomo@vger.kernel.org
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Re: [PATCH net-next-2.6 1/2] be2net: Adding an option to use INTx instead of MSI-X

[Matthew Wilcox]

On Tue, Oct 26, 2010 at 05:52:08PM +1100, Michael Ellerman wrote:
> That horse has really really bolted, it's gawn.
> 
> I count 26 drivers with "disable MSI/X" parameters. Some even have more
> than one.

That's 26 patches someone needs to write, then.  You can put my Acked-by
on all of them.

> I agree it's a mess for users, but it's probably preferable to a
> non-working driver.

What more drivers need is an automatic detection of a non-working
interrupt situation, great big warning messages, and fallback to an
alternate interrupt mechanism.  Doing it for one driver, then generalising
as much of it into the core as possible would be nice.

-- 
Matthew Wilcox				Intel Open Source Technology Centre
"Bill, look, we understand that you're interested in selling us this
operating system, but compare it to ours.  We can't possibly take such
a retrograde step."

Re: [PATCH net-next-2.6 1/2] be2net: Adding an option to use INTx instead of MSI-X

[Michael Ellerman]

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On Sat, 2010-10-30 at 17:21 -0600, Matthew Wilcox wrote:
> On Tue, Oct 26, 2010 at 05:52:08PM +1100, Michael Ellerman wrote:
> > That horse has really really bolted, it's gawn.
> > 
> > I count 26 drivers with "disable MSI/X" parameters. Some even have more
> > than one.
> 
> That's 26 patches someone needs to write, then.  You can put my Acked-by
> on all of them.

Bah, come on it's hardly the most horrendous sin committed by driver
writers. And removing them risks breaking someone's system, even if they
are clueless, should RTFM etc.

> > I agree it's a mess for users, but it's probably preferable to a
> > non-working driver.
> 
> What more drivers need is an automatic detection of a non-working
> interrupt situation, great big warning messages, and fallback to an
> alternate interrupt mechanism.  Doing it for one driver, then generalising
> as much of it into the core as possible would be nice.

More detection would be good.

I don't see much potential for generalising it though. Looking at e1000e
and tg3 there is really not much in common except the very basic idea.

cheers



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Re: [PATCH net-next-2.6 1/2] be2net: Adding an option to use INTx instead of MSI-X

[David Miller]

From: Michael Ellerman <michael@ellerman.id.au>
Date: Wed, 03 Nov 2010 23:45:57 +1100

> On Sat, 2010-10-30 at 17:21 -0600, Matthew Wilcox wrote:
>> On Tue, Oct 26, 2010 at 05:52:08PM +1100, Michael Ellerman wrote:
>> > That horse has really really bolted, it's gawn.
>> > 
>> > I count 26 drivers with "disable MSI/X" parameters. Some even have more
>> > than one.
>> 
>> That's 26 patches someone needs to write, then.  You can put my Acked-by
>> on all of them.
> 
> Bah, come on it's hardly the most horrendous sin committed by driver
> writers.

Yes but it's pretty high on the list because it deteriorates the
user experience.

It's a real selfish move to try and "fix" things in this way and
we've established that this isn't acceptable in the past.