[9fans] bugs, races, more bugs

[9fans] bugs, races, more bugs

[David Presotto]

Timing out arp entries uncovered some bugs that we
hadn't noticed before plus I added one with the
timeouts.  The symptom was quiescent connections
timing out.  Fixed in ip/arp.c.

We also found a few races between packets being rerouted
and IP stacks being torn down.  The symptom was
a null dereference in ip.c crashing the kernel.
Fixed in ip/ip.c, ip/ipifc.c, ip/iproute.c,
ip/ipv6.c.  I left an assert in ip.c to make
the race more obvious in case we haven't stomped
on it yet.

Finally, I updated port/proc.c and port/devproc.c
with suggestions on scheduler changes from the list.
Processes trapped at low priority levels now float
up.  Also, sleep(0) now drops a process' priority
one level each call so that processes doing something
like:

	while(condition not true)
		sleep(0);

should dip down below whatever its waiting for.
I've been testing it on all our systems for a few
days and haven't seen a problem.  However, I never trust
this stuff till a wider audience tries it.  Could
people that didn't do well with the last version
try this out soon?

[9fans] bugs, races, more bugs

[Fco.J.Ballesteros]

> this stuff till a wider audience tries it.  Could
> people that didn't do well with the last version
> try this out soon?

A pull from sources shows no changes (yet).
I'll try that as soon as I pull them out of sources.

Thanks a lot

Re: [9fans] bugs, races, more bugs

[Lucio De Re]

On Tue, Mar 18, 2003 at 03:53:26PM +0100, Fco.J.Ballesteros wrote:
> 
> > this stuff till a wider audience tries it.  Could
> > people that didn't do well with the last version
> > try this out soon?
> 
> A pull from sources shows no changes (yet).
> I'll try that as soon as I pull them out of sources.
> 
Curious.  I was busy pulling this morning (local) and got the files,
apparently shortly before I got to _read_ Dave's mail.  They were
definitely there.

++L

Re: [9fans] bugs, races, more bugs

[Fco.J.Ballesteros]

[-- Attachment #1: Type: text/plain, Size: 348 bytes --]

Perhaps I have something wrong in my log files. I'll check by hand.
thanks.

PS: I did a pull not long ago, and it pulled some files
including the changes in the scheduler, but the pull did not
include the fixes made by Presotto. Are you sure your pull does?
Perhaps your pull includes just the changed scheduler, which
was before the fixes.

[-- Attachment #2: Type: message/rfc822, Size: 2271 bytes --]

From: Lucio De Re <lucio@proxima.alt.za>
To: 9fans@cse.psu.edu
Subject: Re: [9fans] bugs, races, more bugs
Date: Tue, 18 Mar 2003 17:17:28 +0200
Message-ID: <20030318171728.A19000@cackle.proxima.alt.za>

On Tue, Mar 18, 2003 at 03:53:26PM +0100, Fco.J.Ballesteros wrote:
> 
> > this stuff till a wider audience tries it.  Could
> > people that didn't do well with the last version
> > try this out soon?
> 
> A pull from sources shows no changes (yet).
> I'll try that as soon as I pull them out of sources.
> 
Curious.  I was busy pulling this morning (local) and got the files,
apparently shortly before I got to _read_ Dave's mail.  They were
definitely there.

++L

Re: [9fans] bugs, races, more bugs

[Lucio De Re]

On Tue, Mar 18, 2003 at 04:19:27PM +0100, Fco.J.Ballesteros wrote:
> 
> Perhaps I have something wrong in my log files. I'll check by hand.
> thanks.
> 
> PS: I did a pull not long ago, and it pulled some files
> including the changes in the scheduler, but the pull did not
> include the fixes made by Presotto. Are you sure your pull does?
> Perhaps your pull includes just the changed scheduler, which
> was before the fixes.

This is what I logged:

1047952838 0 c sys/src/9/ip/arp.c - 664 sys sys 1047951324 10671
1047952838 1 c sys/src/9/ip/ip.c - 664 sys sys 1047951326 15285
1047952838 2 c sys/src/9/ip/ipifc.c - 664 sys sys 1047951327 37830
1047952838 3 c sys/src/9/ip/iproute.c - 664 sys sys 1047951327 14767
1047952838 4 c sys/src/9/ip/ipv6.c - 664 sys sys 1047951328 14433
1047952838 5 c sys/src/9/port/devproc.c - 664 sys sys 1047952847 23450
1047952838 6 c sys/src/9/port/proc.c - 664 sys sys 1047952847 24170

I hope it helps.

++L

Re: [9fans] bugs, races, more bugs

[David Presotto]

I also stuck out sys/src/9/port/sysproc.c, sys/src/9/port/portdat.h,
sys/src/9/port/portfns.h this morning after someone nodticed that
I'ld forgotten.  Don't know when the pull sweep will find those.