Re: [PATCH] DOCUMENTATION: Fixed typo in an example in memory-barriers.txt
From: Randy Dunlap
Date: Sat Aug 23 2014 - 14:01:25 EST
On 08/22/14 23:05, Ganesh Rapolu wrote:
> In the first example in the memory-barriers.txt file, CPU 2 is assigned to
> run (x = B; y = A;). However, the rest of the example proceeds as if CPU 2 had been
> running (x = A; y = B;) as shown by the descriptions of the possible executions:
>
> STORE A=3, STORE B=4, x=LOAD A->3, y=LOAD B->4
> STORE A=3, STORE B=4, y=LOAD B->4, x=LOAD A->3
> STORE A=3, x=LOAD A->3, STORE B=4, y=LOAD B->4
> STORE A=3, x=LOAD A->3, y=LOAD B->2, STORE B=4
> STORE A=3, y=LOAD B->2, STORE B=4, x=LOAD A->3
> STORE A=3, y=LOAD B->2, x=LOAD A->3, STORE B=4
> STORE B=4, STORE A=3, x=LOAD A->3, y=LOAD B->4
> STORE B=4, ...
> ...
>
> The change was merely to make the inital evironment consistent with what happens in the
> rest of the example.
>
> Signed-off-by: Ganesh Rapolu <ganesh.rapolu@xxxxxxxxxxx>
Comments David, Alexey, Andrew, Paul?
This would revert Alexey's patch 615cc2c9cf9529846fbc342560d6787c2ccaaeea:
"Documentation/memory-barriers.txt: fix important typo re memory barriers"
that was merged on June 6, 2014.
Thanks.
> ---
> Documentation/memory-barriers.txt | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/Documentation/memory-barriers.txt b/Documentation/memory-barriers.txt
> index a4de88f..9a46bbe 100644
> --- a/Documentation/memory-barriers.txt
> +++ b/Documentation/memory-barriers.txt
> @@ -115,8 +115,8 @@ For example, consider the following sequence of events:
> CPU 1 CPU 2
> =============== ===============
> { A == 1; B == 2 }
> - A = 3; x = B;
> - B = 4; y = A;
> + A = 3; x = A;
> + B = 4; y = B;
>
> The set of accesses as seen by the memory system in the middle can be arranged
> in 24 different combinations:
>
--
~Randy
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