From: Bob McElrath <rsmcelrath@students.wisc.edu>
To: Andrea Arcangeli <andrea@suse.de>
Cc: linux-kernel@vger.kernel.org
Subject: Re: it isn't aa's rwsem-generic-6 bug but something else [Re: aa's rwsem-generic-6 bug? Process stuck in 'R' state.]
Date: Thu, 26 Apr 2001 11:10:34 -0500 [thread overview]
Message-ID: <20010426111034.B5697@draal.physics.wisc.edu> (raw)
In-Reply-To: <20010425223939.A26763@draal.physics.wisc.edu> <20010426061110.A819@athlon.random> <20010426003802.A738@draal.physics.wisc.edu> <20010426174553.B819@athlon.random>
In-Reply-To: <20010426174553.B819@athlon.random>; from andrea@suse.de on Thu, Apr 26, 2001 at 05:45:53PM +0200
[-- Attachment #1: Type: text/plain, Size: 1579 bytes --]
Andrea Arcangeli [andrea@suse.de] wrote:
> On Thu, Apr 26, 2001 at 12:38:02AM -0500, Bob McElrath wrote:
> > When I posted this bug originally, you came right out and said it was
> > probably the rwsemaphores. I really have no idea how the rwsemaphores
>
> You were talking about the ps table hang when I told you about the rwsem
> races. I had the same trouble on my alpha and I reproduced the races
> trivially by lanucing:
>
> make MAKE='make -j2' -j2 &
>
> while :; do ps xa ; sleep 1 ; done
>
> After a few seconds ps deadlocked. Try that on the old asm semaphores.
This does not cause a hang on my machine with your new rwsemaphores.
> It was 100% reproducible, and after I rewrote the rwsemaphores the
> deadlock gone away completly.
>
> Your X hanging in R state is completly unrelated to the rwsem ps table
> hang problem as far I can tell.
Ok, so what are the other alternatives? In the R state, the scheduler
should give it some CPU at the first available jiffy, correct? After
several minutes it was still stuck in the R state, and had received 0
CPU time.
Could this be a scheduler bug?
Another thing I just noticed: watching the ps list, gcc is getting
called with -mcpu=ev56, which in turn is calling as with -mev6. Since
this is an ev56 processor, not the newer ev6, this could conceivable be
generating illegal instructions, though I haven't ever seen any kernel
illegal instruction faults.
*Sigh*
-- Bob
Bob McElrath (rsmcelrath@students.wisc.edu)
Univ. of Wisconsin at Madison, Department of Physics
[-- Attachment #2: Type: application/pgp-signature, Size: 240 bytes --]
prev parent reply other threads:[~2001-04-26 16:11 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2001-04-26 3:39 aa's rwsem-generic-6 bug? Process stuck in 'R' state Bob McElrath
2001-04-26 4:11 ` it isn't aa's rwsem-generic-6 bug but something else [Re: aa's rwsem-generic-6 bug? Process stuck in 'R' state.] Andrea Arcangeli
2001-04-26 5:38 ` Bob McElrath
2001-04-26 15:45 ` Andrea Arcangeli
2001-04-26 16:10 ` Bob McElrath [this message]
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20010426111034.B5697@draal.physics.wisc.edu \
--to=rsmcelrath@students.wisc.edu \
--cc=andrea@suse.de \
--cc=linux-kernel@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.