This series of patches extend the alternative instructions framework on i386 and x86_64 architectures to support two alternative instruction replacements. This code is used together with the introduction of the X86_FEATURE_SYNC_RDTSC flag on i386 to simplify and optimize the get_cycles_sync() function. The optimization changes this function to use RDTSCP instead of CPUID;RDTSC if this instruction is available. Don't use CPUID there is really important if the kernel runs as a KVM guest, because this instruction is intercepted and causes an expensive VMEXIT.
Changes to the previous submit: * rebased to current linus git tree * replaced RDTSCP usage in get_cycles_sync with the opcode to make it compile with older binutils -- Joerg Roedel Operating System Research Center AMD Saxony LLC & Co. KG - 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/
