From owner-freebsd-alpha  Fri May 10 12:41:42 2002
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Date: Fri, 10 May 2002 14:41:33 -0500
From: Alan Cox <alc@cs.rice.edu>
To: alpha@freebsd.org
Cc: gallatin@cs.duke.edu
Subject: Re: gcc3 & alpha kernels
Message-ID: <20020510194133.GA13871@cs.rice.edu>
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> I do NOT know if this was the fault of gcc3, but it smells like it.
> According to nm, this address is in _vm_object_allocate().  A few
> other times, it locked with an address in what looked like mlock().

A few days ago Jeff Robertson had a problem in this neighborhood
on alpha triggered by an atomic_cmpset_int() that I had introduced
in _vm_object_allocate().  He resolved with the following change
to src/sys/alpha/include/atomic.h:

Revision 1.12 / (download) - annotate - [select for diffs], Wed May 8 05:19:56 2002 UTC (2 days, 13 hours ago) by jeff 
Branch: MAIN 
CVS Tags: HEAD 
Changes since 1.11: +2 -1 lines
Diff to previous 1.11 (colored)

zapnot the signed bits in atomic_cmpset_32.  Previously this did not work with
negative values because the original value was sign extended but the compared
value was not.

If I'm not mistaken, prior to this change, he locked up
in _vm_object_allocate() much as Andrew described.

Alan

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