On Sat, Nov 22, 2008 at 11:08 PM, Scott Long <[EMAIL PROTECTED]> wrote: > Kostik Belousov wrote: >> >> On Sat, Nov 22, 2008 at 03:05:22PM -0700, Scott Long wrote: >>> >>> A neat hack would be for the kernel linker to scan the text and do a >>> drop-in replacement of the opcode that is appropriate for the platform. >>> I can't see how a CPU_XXX definition would work because it's just a >>> compile time construct, one that can be included with any kernel >>> compile. >> >> Yes, it is possible to do that. Less drastic change is to directly >> check features. I moved slow code to separate section to eliminate >> unconditional jump in fast path. >> Only compile-tested. >> > > As long as it works, I think it's a step in the right direction; I'm > assuming that cpu_feature is a symbol filled in at runtime and not a > macro for the cpuid instruction, right? > > Scott >
i386/include/md_var.h: <..> extern u_int cpu_exthigh; extern u_int cpu_feature; extern u_int cpu_feature2; extern u_int amd_feature; extern u_int amd_feature2; <...> I'm not thrilled with it, but we can revisit the issue if it makes a measurable difference on someone's workload. Thanks, Kip -- If we desire respect for the law, we must first make the law respectable. - Louis D. Brandeis _______________________________________________ svn-src-all@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/svn-src-all To unsubscribe, send any mail to "[EMAIL PROTECTED]"
