On Thu, Nov 29, 2007 at 11:16:55AM -0800, H. Peter Anvin wrote: > Andi, do you happen to remember the details on this? x86-64 has to use GS because there is no SWAPFS We decided to make it opposite on user space back then, but not based on benchmarks (there were only simulators back then) Oh yes the reason was that the GS context switch is slightly more expensive than the FS one and the code does lazy optimization. For i386 iirc Jeremy/Zach did the benchmarking and they settled on %fs because it was faster for something (originally it was %gs too) -Andi - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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