Re: bit fields && data tearing
From: Paul E. McKenney <hidden>
Date: 2014-09-05 20:11:42
Also in:
linux-alpha, linux-arch, lkml
On Fri, Sep 05, 2014 at 03:24:35PM -0400, Peter Hurley wrote:
On 09/05/2014 03:05 PM, Paul E. McKenney wrote:quoted
On Fri, Sep 05, 2014 at 02:50:31PM -0400, Peter Hurley wrote:quoted
On 09/05/2014 02:09 PM, Paul E. McKenney wrote:[cut]quoted
quoted
quoted
------------------------------------------------------------------------ documentation: Record limitations of bitfields and small variables This commit documents the fact that it is not safe to use bitfields as shared variables in synchronization algorithms. It also documents that CPUs must provide one-byte and two-byte load and store instructions^ atomicHere you meant non-atomic? My guess is that you are referring to the fact that you could emulate a one-byte store on pre-EV56 Alpha CPUs using the ll and sc atomic-read-modify-write instructions, correct?Yes, that's what I meant. I must be tired and am misreading the commit message, or misinterpreting it's meaning.
Very good, got it! Thanx, Paul