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Date: Thu, 1 Oct 1998 12:56:31 -0700 (PDT)
From: Matthew Dillon <dillon@backplane.com>
Message-Id: <199810011956.MAA05613@apollo.backplane.com>
To: Guido van Rooij <guido@gvr.org>
Cc: Poul-Henning Kamp <phk@critter.freebsd.dk>, John Birrell <jb@FreeBSD.ORG>,
        cvs-committers@FreeBSD.ORG, cvs-all@FreeBSD.ORG
Subject: Re: cvs commit: src/lib/libc_r/uthread uthread_gc.c Makefile.inc uthread_init.c uthread_find_thread.c uthread_kern.c uthread_create.c uthread_exit.c
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    The only thing you can assume as being atomic is a read or write, never
    a read-modify-write, because you never know what kind of optimizations
    (or lack thereof) the compiler will perform and also because some cpu's
    simply do not have a locked RMW capability.

						-Matt

    Matthew Dillon  Engineering, HiWay Technologies, Inc. & BEST Internet 
                    Communications & God knows what else.
    <dillon@backplane.com> (Please include original email in any response)