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* RE: NS83820 2.6.0-test5 driver seems unstable on IA64
@ 2003-09-23 17:58 Van Maren, Kevin
  2003-09-23 17:57 ` David S. Miller
  2003-09-23 18:06 ` David Mosberger
  0 siblings, 2 replies; 81+ messages in thread
From: Van Maren, Kevin @ 2003-09-23 17:58 UTC (permalink / raw)
  To: David S. Miller, davidm
  Cc: davidm, peter, bcrl, ak, iod00d, peterc, linux-ns83820,
	linux-ia64, linux-kernel

> > The printk() is rate-controlled and doesn't happen for every unaligned
> > access.  It's average cost can be made as low as we want to, by adjusting
> > the rate.
> 
> But if the event is normal, you shouldn't be logging it as if
> it weren't.

That's my view on the fpswa printk's (handle_fpu_swa): they are normal,
expected, and there is absolutely nothing that can be done about them --
so why print a "warning" about them (even if it is only 5 per second)?
If nothing else, toggle the meaning for IA64_THREAD_FPEMU_NOPRINT: turn it
ON for special apps.

Rate-limited unaligned loads in user space make a lot more sense, since
they _may_ point out issues in the code.

Kevin

^ permalink raw reply	[flat|nested] 81+ messages in thread
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* Re: NS83820 2.6.0-test5 driver seems unstable on IA64
@ 2003-09-26  6:16 Manfred Spraul
  2003-09-26  6:07 ` David S. Miller
  0 siblings, 1 reply; 81+ messages in thread
From: Manfred Spraul @ 2003-09-26  6:16 UTC (permalink / raw)
  To: David S. Miller; +Cc: linux-kernel

David wrote:

>Fine, then we should have something like an rx_copybreak scheme in
>the ns83820 driver too.
>  
>
Is that really the right solution? Add a full-packet copy to every driver?
IMHO the fastest solution would be to copy only the ip & tcp headers, 
and keep the rest as it is. And preferable in the network core, to avoid 
having to copy&paste that into every driver.

--
    Manfred


^ permalink raw reply	[flat|nested] 81+ messages in thread
* RE: NS83820 2.6.0-test5 driver seems unstable on IA64
@ 2003-09-23 22:58 Luck, Tony
  2003-09-23 23:32 ` David S. Miller
  2003-09-24  5:18 ` Valdis.Kletnieks
  0 siblings, 2 replies; 81+ messages in thread
From: Luck, Tony @ 2003-09-23 22:58 UTC (permalink / raw)
  To: Alan Cox
  Cc: David S. Miller, davidm, davidm, peter, bcrl, ak, iod00d, peterc,
	linux-ns83820, linux-ia64, Linux Kernel Mailing List

Alan Cox wrote:
> On Maw, 2003-09-23 at 19:21, Luck, Tony wrote:
> > a) the programmer is playing fast and loose with types and/or casts.
> > b) the end-user is going to be disappointed with the performance.
> 
> c) the programmer is being clever and knows the unaligned access is
> cheaper on average than the cost of making sure it cant happen

Which is great until the "cleverly written" program is fed a data set
that pushes into the unaligned case far more frequently than the
programmer anticipated.

> > Looking at a couple of ia64 build servers here I see zero unaligned
> > access messages in the logs.
> 
> Anyone who can deliver network traffic to your box can soon 
> fix that...

See answer above :-)

-Tony Luck

^ permalink raw reply	[flat|nested] 81+ messages in thread
* RE: NS83820 2.6.0-test5 driver seems unstable on IA64
@ 2003-09-23 18:21 Luck, Tony
  2003-09-23 18:29 ` Benjamin LaHaise
  2003-09-23 21:00 ` Alan Cox
  0 siblings, 2 replies; 81+ messages in thread
From: Luck, Tony @ 2003-09-23 18:21 UTC (permalink / raw)
  To: David S. Miller, davidm
  Cc: davidm, peter, bcrl, ak, iod00d, peterc, linux-ns83820,
	linux-ia64, linux-kernel

> As I understand it, you even do this stupid printk for user apps
> as well, that makes it more than rediculious.  I'd be surprised
> if anyone can find any useful kernel messages on an ia64 system
> in the dmesg output with all the unaligned access crap there.

I don't think that it is "normal" for applications to do unaligned
memory access.  It means that:

a) the programmer is playing fast and loose with types and/or casts.
b) the end-user is going to be disappointed with the performance.

Looking at a couple of ia64 build servers here I see zero unaligned
access messages in the logs.

-Tony

^ permalink raw reply	[flat|nested] 81+ messages in thread
* NS83820 2.6.0-test5 driver seems unstable on IA64
@ 2003-09-19  4:16 Peter Chubb
  2003-09-19  4:38 ` Grant Grundler
  0 siblings, 1 reply; 81+ messages in thread
From: Peter Chubb @ 2003-09-19  4:16 UTC (permalink / raw)
  To: linux-ns83820; +Cc: linux-ia64, linux-kernel


Hi,
	I'm having some problems with the NS83820 driver on Itanium-1.

1.  I see many many `unaligned accesses' when the IP header is
accessed (ip_input.c:410 and 423)
It looks as if the IP header is two byte aligned, when it ought to be
4-byte aligned.

The error message is, e.g., 
 kernel unaligned access to 0xe000000128d8881e, ip=0xe0000000047ba2d1

0xe0000000047ba2d1 is             
ip_input:410
		   if (iph->ihl < 5 || iph->version != 4)
		                goto inhdr_error; 

0xe000000128d8881e is what's calculated as &iph->ihl

The obvious approach of realigning the SKB by 2 bytes seems not to
work.

Any ideas?

--
Dr Peter Chubb     http://www.gelato.unsw.edu.au  peterc@gelato.unsw.edu.au
You are lost in a maze of BitKeeper repositories,   all slightly different.


^ permalink raw reply	[flat|nested] 81+ messages in thread

end of thread, other threads:[~2003-09-27 23:50 UTC | newest]

Thread overview: 81+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2003-09-23 17:58 NS83820 2.6.0-test5 driver seems unstable on IA64 Van Maren, Kevin
2003-09-23 17:57 ` David S. Miller
2003-09-23 18:27   ` David Mosberger
2003-09-23 18:47     ` David S. Miller
2003-09-23 19:17       ` David Mosberger
2003-09-23 19:10         ` David S. Miller
2003-09-23 20:00           ` David Mosberger
2003-09-24  3:08             ` David S. Miller
2003-09-25 16:11               ` Ivan Kokshaysky
2003-09-26  1:12                 ` David S. Miller
2003-09-23 18:06 ` David Mosberger
2003-09-23 19:11   ` David S. Miller
     [not found] <A4gy.8wi.13@gated-at.bofh.it>
     [not found] ` <A4gy.8wi.15@gated-at.bofh.it>
     [not found]   ` <A4gy.8wi.17@gated-at.bofh.it>
     [not found]     ` <A4gy.8wi.11@gated-at.bofh.it>
     [not found]       ` <A4Tv.Ud.37@gated-at.bofh.it>
     [not found]         ` <AepM.5Zb.41@gated-at.bofh.it>
2003-09-27  4:26           ` Andi Kleen
2003-09-27  4:34             ` David Mosberger
2003-09-27 23:36             ` David S. Miller
     [not found] <A2yd.64p.31@gated-at.bofh.it>
     [not found] ` <A2yd.64p.29@gated-at.bofh.it>
     [not found]   ` <A317.6GH.7@gated-at.bofh.it>
2003-09-26 17:04     ` Andi Kleen
2003-09-26 17:22       ` Chris Friesen
2003-09-26 17:47       ` David Mosberger
2003-09-27  3:57         ` David S. Miller
2003-09-27  4:36         ` Andi Kleen
2003-09-27  4:52           ` David Mosberger
     [not found] <zU7D.2Ji.27@gated-at.bofh.it>
2003-09-26 15:14 ` Andi Kleen
2003-09-26 15:41   ` David Mosberger
  -- strict thread matches above, loose matches on Subject: below --
2003-09-26  6:16 Manfred Spraul
2003-09-26  6:07 ` David S. Miller
2003-09-26  6:41   ` David Mosberger
2003-09-26 14:38   ` Ivan Kokshaysky
2003-09-27  3:12     ` David S. Miller
2003-09-23 22:58 Luck, Tony
2003-09-23 23:32 ` David S. Miller
2003-09-24  5:18 ` Valdis.Kletnieks
2003-09-23 18:21 Luck, Tony
2003-09-23 18:29 ` Benjamin LaHaise
2003-09-23 18:45   ` David S. Miller
2003-09-23 18:51   ` Grant Grundler
2003-09-23 18:51     ` David S. Miller
2003-09-23 20:38       ` Grant Grundler
2003-09-23 20:45         ` David S. Miller
2003-09-23 22:35           ` Grant Grundler
2003-09-23 23:35             ` David S. Miller
2003-09-24  0:13               ` Grant Grundler
2003-09-24  0:04                 ` David S. Miller
2003-09-24  1:58               ` William Lee Irwin III
2003-09-23 19:04     ` Benjamin LaHaise
2003-09-23 18:54   ` Andreas Schwab
2003-09-23 18:52     ` David S. Miller
2003-09-23 19:09       ` Andreas Schwab
2003-09-23 19:01         ` David S. Miller
2003-09-23 19:16           ` Andreas Schwab
2003-09-23 19:08             ` David S. Miller
2003-09-23 19:28       ` Matthew Wilcox
2003-09-23 19:22         ` David S. Miller
2003-09-23 23:15           ` Andrew Morton
2003-09-23 23:37             ` David S. Miller
2003-09-24  0:14               ` Matthew Wilcox
2003-09-24  0:06                 ` David S. Miller
2003-09-23 19:10   ` Jeff Garzik
2003-09-23 19:11     ` Benjamin LaHaise
2003-09-23 19:22       ` Jeff Garzik
2003-09-23 21:00 ` Alan Cox
2003-09-23 21:16   ` David Mosberger
2003-09-24  1:47     ` David S. Miller
2003-09-19  4:16 Peter Chubb
2003-09-19  4:38 ` Grant Grundler
2003-09-19  4:43   ` Andi Kleen
2003-09-19  5:01     ` Peter Chubb
2003-09-19  5:53       ` Andi Kleen
2003-09-19 10:49         ` Benjamin LaHaise
2003-09-23  0:34           ` Peter Chubb
2003-09-23  0:36             ` Benjamin LaHaise
2003-09-23  6:22               ` David S. Miller
2003-09-23 10:40                 ` Peter Chubb
2003-09-23 10:51                   ` David S. Miller
2003-09-23 14:59                     ` David Mosberger
2003-09-23 17:27                       ` David S. Miller
2003-09-23 17:56                         ` David Mosberger
2003-09-24  2:55                           ` David S. Miller
2003-09-23 23:04                         ` Ian Wienand
2003-09-23 23:35                           ` David S. Miller
2003-09-19  5:04     ` Grant Grundler
2003-09-19  5:11       ` Peter Chubb

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