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From: erik quanstrom <quanstro@quanstro.net>
To: 9fans@9fans.net
Subject: [9fans] waitfree
Date: Mon, 19 May 2014 13:34:33 -0400	[thread overview]
Message-ID: <ac0a74a8fd1972cd1c72c7b5983fdc4e@ladd.quanstro.net> (raw)

i've been thinking about ainc() and for the amd64 implementation,

	TEXT ainc(SB), 1, $-4			/* int ainc(int*) */
		MOVL	$1, AX
		LOCK; XADDL AX, (RARG)
		ADDL	$1, AX
		RET

does anyone know if the architecture says this is wait-free?
this boils down to exactly how LOCK works, and i can't find
a good-enough definition.  i tend to think that it might not be.

- erik



             reply	other threads:[~2014-05-19 17:34 UTC|newest]

Thread overview: 14+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-05-19 17:34 erik quanstrom [this message]
2014-05-19 19:49 ` Devon H. O'Dell
2014-05-19 20:21   ` erik quanstrom
2014-05-19 21:01     ` Devon H. O'Dell
2014-05-19 22:05       ` erik quanstrom
2014-05-19 22:14         ` ron minnich
2014-05-19 22:18           ` erik quanstrom
2014-05-20  1:10         ` Devon H. O'Dell
2014-05-20  2:12           ` erik quanstrom
2014-05-20 14:47             ` Devon H. O'Dell
2014-05-20 15:41               ` erik quanstrom
2014-05-20 19:14                 ` Devon H. O'Dell
2014-05-20 19:30                   ` erik quanstrom
2014-05-20 20:32                     ` Devon H. O'Dell

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