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To: Sebastian Huber <sebastian.huber@embedded-brains.de>
cc: freebsd-hackers@freebsd.org
Subject: Re: Problem with timecounters and memory model
In-reply-to: <55686300.3080100@embedded-brains.de>
From: "Poul-Henning Kamp" <phk@phk.freebsd.dk>
References: <55686300.3080100@embedded-brains.de>
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Date: Fri, 29 May 2015 13:36:18 +0000
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--------
In message <55686300.3080100@embedded-brains.de>, Sebastian Huber writes:

>This version seems to work at least on uni-processor systems. Shouldn't
>there be real memory barriers the synchronize the reads/writes to
>th_generation for SMP machines?

yes, there should.

(I must admit that I havn't looked at that code for about five or ten years.)

-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk@FreeBSD.ORG         | TCP/IP since RFC 956
FreeBSD committer       | BSD since 4.3-tahoe    
Never attribute to malice what can adequately be explained by incompetence.