2008-11-13 04:14:49

by Marcel Holtmann

[permalink] [raw]
Subject: Issue with ifconfig down and 4965 driver

Hi guys,

so I am running a 2.6.28-rc4 kernel and every time I stop
wpa_supplicant or call ifconfig down on the 4965 card, I get a user
noticeable delay (mouse freezes). Seems that some part inside the
driver is actively sleeping with a busy-loop. This is really not an
acceptable behavior since it is a day-to-day task to bring the device
down. And for power concerns, we really wanna allow to bring down the
interface.

Regards

Marcel



2008-11-13 10:11:34

by Marcel Holtmann

[permalink] [raw]
Subject: Re: Issue with ifconfig down and 4965 driver

Hi Reinette,

>> so I am running a 2.6.28-rc4 kernel and every time I stop
>> wpa_supplicant or call ifconfig down on the 4965 card, I get a user
>> noticeable delay (mouse freezes). Seems that some part inside the
>> driver is actively sleeping with a busy-loop. This is really not an
>> acceptable behavior since it is a day-to-day task to bring the device
>> down. And for power concerns, we really wanna allow to bring down the
>> interface.
>>
>
> Please add your information to
> http://www.intellinuxwireless.org/bugzilla/show_bug.cgi?id=1790

all information are already in the Bugzilla. It is nothing fancy and
easy to reproduce. Do we have a patch for it?

Regards

Marcel


2008-11-13 05:47:35

by Reinette Chatre

[permalink] [raw]
Subject: Re: Issue with ifconfig down and 4965 driver

On Wed, 2008-11-12 at 20:14 -0800, Marcel Holtmann wrote:
> Hi guys,
>
> so I am running a 2.6.28-rc4 kernel and every time I stop
> wpa_supplicant or call ifconfig down on the 4965 card, I get a user
> noticeable delay (mouse freezes). Seems that some part inside the
> driver is actively sleeping with a busy-loop. This is really not an
> acceptable behavior since it is a day-to-day task to bring the device
> down. And for power concerns, we really wanna allow to bring down the
> interface.
>

Please add your information to
http://www.intellinuxwireless.org/bugzilla/show_bug.cgi?id=1790

Reinette


2008-12-02 20:26:27

by Reinette Chatre

[permalink] [raw]
Subject: Re: Issue with ifconfig down and 4965 driver

On Thu, 2008-11-13 at 01:45 -0800, Marcel Holtmann wrote:
> Hi Reinette,
>
> >> so I am running a 2.6.28-rc4 kernel and every time I stop
> >> wpa_supplicant or call ifconfig down on the 4965 card, I get a user
> >> noticeable delay (mouse freezes). Seems that some part inside the
> >> driver is actively sleeping with a busy-loop. This is really not an
> >> acceptable behavior since it is a day-to-day task to bring the device
> >> down. And for power concerns, we really wanna allow to bring down the
> >> interface.
> >>
> >
> > Please add your information to
> > http://www.intellinuxwireless.org/bugzilla/show_bug.cgi?id=1790
>
> all information are already in the Bugzilla. It is nothing fancy and
> easy to reproduce. Do we have a patch for it?
>

http://marc.info/?l=linux-wireless&m=122824886623698&w=2


Reinette


2008-12-04 17:22:49

by Reinette Chatre

[permalink] [raw]
Subject: Re: Issue with ifconfig down and 4965 driver

On Thu, 2008-12-04 at 03:19 -0800, Marcel Holtmann wrote:
> Hi Reinette,
>
> > > > > >> so I am running a 2.6.28-rc4 kernel and every time I stop
> > > > > >> wpa_supplicant or call ifconfig down on the 4965 card, I get a user
> > > > > >> noticeable delay (mouse freezes). Seems that some part inside the
> > > > > >> driver is actively sleeping with a busy-loop. This is really not an
> > > > > >> acceptable behavior since it is a day-to-day task to bring the device
> > > > > >> down. And for power concerns, we really wanna allow to bring down the
> > > > > >> interface.
> > > > > >>
> > > > > >
> > > > > > Please add your information to
> > > > > > http://www.intellinuxwireless.org/bugzilla/show_bug.cgi?id=1790
> > > > >
> > > > > all information are already in the Bugzilla. It is nothing fancy and
> > > > > easy to reproduce. Do we have a patch for it?
> > > > >
> > > >
> > > > http://marc.info/?l=linux-wireless&m=122824886623698&w=2
> > >
> > > so I finally got around testing the patch. It is great that it reduces
> > > the time drastically, but I think that it is still not good enough. So I
> > > don't care how long it takes to bring the device down. My concern is
> > > that we are busy-looping during this time. Meaning the kernel is not
> > > responding to anything. Simple symptom is that the mouse is stuck.
> > >
> >
> > We have found that this one patch is not the full solution. More work is
> > currently being done with activity tracked at
> > http://www.intellinuxwireless.org/bugzilla/show_bug.cgi?id=1790
>
> I quickly checked Mohamed's last patch. It actually makes it worse on my
> system.

Thank you very much for testing - I will let him know. Would it be
possible to add your feedback to that bug report for visibility to
everybody tracking that problem? Not everybody there are subscribed to
linux-wireless and other people testing the patch (see last comment #12)
reports that the issue is solved for them.

Thank you very much

Reinette



2008-12-03 23:38:41

by Marcel Holtmann

[permalink] [raw]
Subject: Re: Issue with ifconfig down and 4965 driver

Hi Reinette,

> > >> so I am running a 2.6.28-rc4 kernel and every time I stop
> > >> wpa_supplicant or call ifconfig down on the 4965 card, I get a user
> > >> noticeable delay (mouse freezes). Seems that some part inside the
> > >> driver is actively sleeping with a busy-loop. This is really not an
> > >> acceptable behavior since it is a day-to-day task to bring the device
> > >> down. And for power concerns, we really wanna allow to bring down the
> > >> interface.
> > >>
> > >
> > > Please add your information to
> > > http://www.intellinuxwireless.org/bugzilla/show_bug.cgi?id=1790
> >
> > all information are already in the Bugzilla. It is nothing fancy and
> > easy to reproduce. Do we have a patch for it?
> >
>
> http://marc.info/?l=linux-wireless&m=122824886623698&w=2

so I finally got around testing the patch. It is great that it reduces
the time drastically, but I think that it is still not good enough. So I
don't care how long it takes to bring the device down. My concern is
that we are busy-looping during this time. Meaning the kernel is not
responding to anything. Simple symptom is that the mouse is stuck.

Regards

Marcel



2008-12-04 11:19:56

by Marcel Holtmann

[permalink] [raw]
Subject: Re: Issue with ifconfig down and 4965 driver

Hi Reinette,

> > > > >> so I am running a 2.6.28-rc4 kernel and every time I stop
> > > > >> wpa_supplicant or call ifconfig down on the 4965 card, I get a user
> > > > >> noticeable delay (mouse freezes). Seems that some part inside the
> > > > >> driver is actively sleeping with a busy-loop. This is really not an
> > > > >> acceptable behavior since it is a day-to-day task to bring the device
> > > > >> down. And for power concerns, we really wanna allow to bring down the
> > > > >> interface.
> > > > >>
> > > > >
> > > > > Please add your information to
> > > > > http://www.intellinuxwireless.org/bugzilla/show_bug.cgi?id=1790
> > > >
> > > > all information are already in the Bugzilla. It is nothing fancy and
> > > > easy to reproduce. Do we have a patch for it?
> > > >
> > >
> > > http://marc.info/?l=linux-wireless&m=122824886623698&w=2
> >
> > so I finally got around testing the patch. It is great that it reduces
> > the time drastically, but I think that it is still not good enough. So I
> > don't care how long it takes to bring the device down. My concern is
> > that we are busy-looping during this time. Meaning the kernel is not
> > responding to anything. Simple symptom is that the mouse is stuck.
> >
>
> We have found that this one patch is not the full solution. More work is
> currently being done with activity tracked at
> http://www.intellinuxwireless.org/bugzilla/show_bug.cgi?id=1790

I quickly checked Mohamed's last patch. It actually makes it worse on my
system.

Regards

Marcel



2008-12-03 23:55:58

by Reinette Chatre

[permalink] [raw]
Subject: Re: Issue with ifconfig down and 4965 driver

On Wed, 2008-12-03 at 15:38 -0800, Marcel Holtmann wrote:
> Hi Reinette,
>
> > > >> so I am running a 2.6.28-rc4 kernel and every time I stop
> > > >> wpa_supplicant or call ifconfig down on the 4965 card, I get a user
> > > >> noticeable delay (mouse freezes). Seems that some part inside the
> > > >> driver is actively sleeping with a busy-loop. This is really not an
> > > >> acceptable behavior since it is a day-to-day task to bring the device
> > > >> down. And for power concerns, we really wanna allow to bring down the
> > > >> interface.
> > > >>
> > > >
> > > > Please add your information to
> > > > http://www.intellinuxwireless.org/bugzilla/show_bug.cgi?id=1790
> > >
> > > all information are already in the Bugzilla. It is nothing fancy and
> > > easy to reproduce. Do we have a patch for it?
> > >
> >
> > http://marc.info/?l=linux-wireless&m=122824886623698&w=2
>
> so I finally got around testing the patch. It is great that it reduces
> the time drastically, but I think that it is still not good enough. So I
> don't care how long it takes to bring the device down. My concern is
> that we are busy-looping during this time. Meaning the kernel is not
> responding to anything. Simple symptom is that the mouse is stuck.
>

We have found that this one patch is not the full solution. More work is
currently being done with activity tracked at
http://www.intellinuxwireless.org/bugzilla/show_bug.cgi?id=1790

Reinette