On Fri, 24 Aug 2007, Denys Vlasenko wrote: > On Thursday 16 August 2007 00:22, Paul Mackerras wrote: > > Satyam Sharma writes: > > In the kernel we use atomic variables in precisely those situations > > where a variable is potentially accessed concurrently by multiple > > CPUs, and where each CPU needs to see updates done by other CPUs in a > > timely fashion. That is what they are for. Therefore the compiler > > must not cache values of atomic variables in registers; each > > atomic_read must result in a load and each atomic_set must result in a > > store. Anything else will just lead to subtle bugs. > > Amen.
A "timely" fashion? One cannot rely on something like that when coding. The visibility of updates is insured by barriers and not by some fuzzy notion of "timeliness". - To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
