Lockless uidinfo.

Maciej Sobczak prog at msobczak.com
Tue Aug 21 14:12:02 PDT 2007


John Baldwin wrote:

> Memory barriers on another CPU don't mean anything about the CPU thread 2 is 
> on.

Of course they do. Otherwise they would be completely useless.

 > Memory barriers do not flush caches on other CPUs, etc.

Membars are not about caches, but about visibility and ordering. Cache 
is transparent and that is guaranteed by hardware - there is no need to 
involve any software tricks to make cache work correctly. You can 
influence their performance, but not correctness.

-- 
Maciej Sobczak : http://www.msobczak.com/
Programming    : http://www.msobczak.com/prog/


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