On Wed, Oct 30, 2013 at 11:40:15PM -0700, Paul E. McKenney wrote: > The dependency you are talking about is via the "if" statement? > Even C/C++11 is not required to respect control dependencies. > > This one is a bit annoying. The x86 TSO means that you really only > need barrier(), ARM (recent ARM, anyway) and Power could use a weaker > barrier, and so on -- but smp_mb() emits a full barrier. > > Perhaps a new smp_tmb() for TSO semantics, where reads are ordered > before reads, writes before writes, and reads before writes, but not > writes before reads? Another approach would be to define a per-arch > barrier for this particular case.
Supposing a sane language where we can rely on control flow; would that change the story? I'm afraid I'm now terminally confused between actual proper memory model issues and fucked compilers. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/