From owner-freebsd-arch  Thu May 25  9:14: 7 2000
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Date: Thu, 25 May 2000 09:13:59 -0700 (PDT)
From: Matthew Dillon <dillon@apollo.backplane.com>
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To: Chuck Paterson <cp@bsdi.com>
Cc: "Jordan K. Hubbard" <jkh@zippy.cdrom.com>,
	Terry Lambert <tlambert@primenet.com>, arch@freebsd.org
Subject: Re: Preemptive kernel on older X86 hardware 
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:
:	The good news is that the actual implementation of the
:mutexs is machine dependent and can change wildly over different
:architectures with no need for the callers to know.
:
:Chuck
:
:"Jordan K. Hubbard" wrote on: Thu, 25 May 2000 01:31:23 PDT
:}>     On intel anyway, subroutine calls are *cheap*, especially compared
:}>     to the overhead of a locked instruction or even an L1 cache miss.
:}
:}I don't believe this is true on all the architectures FreeBSD is
:}anticipated to run on in the "near future", however.
:}
:}- Jordan

    Lets use subroutines during development at least, it will make
    things easier.  I don't think anyone can argue with that :-)

					-Matt
					Matthew Dillon 
					<dillon@backplane.com>


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