Oops, the patch had a small mistake. I've put it here now, just in case I'll want to fix/cleanup anything else: http://people.freebsd.org/~avg/intel-cpu-topo.diff
on 28/08/2010 23:22 Andriy Gapon said the following: > So, here is my take on the problem. > The attached patch is against sources in FreeBSD tree, it should be applied > either to sys/amd64/amd64/mp_machdep.c or sys/i386/i386/mp_machdep.c depending > on the desired architecture. > > The patch is substantially based on the Junk-uk's patch, but with some changes > and additions: > - topo_probo_0x4() is rewritten so that it does APIC ID matching against masks > as described in the Intel article. The code still heavily depends on the > assumption of the uniform topology, it discovers number of cores in BSP > package > and number of threads in BSP core and extrapolates that to global topology. > The difference with current code and Junk-uk's patch is that actual APIC ID > matching is done as opposed to deriving counts purely from max. values. > > - added a few comments that describe uniformity assumption, plus couple other > useful things. > > - changed "final fallback" code, so that each logical CPU is considered to be > in > its own physical package as opposed to current code placing all logical CPUs > as > cores of a single package. > > The rest is Junk-uk's work. > > Concerns: > - about my code: ilog2_round_pow2 name is ugly; looking for suggestions on a > better name or re-arranging/writing that code, so that the function is not > needed. > - about current code: logical_cpus variable (don't confuse with cpu_logical) > doesn't seem to be consistently used; e.g. it is not set at all by > topo_probo_0xb(); also, the method of using it for setting logical_cpus_mask > doesn't seem to be reliable - BSP may be missed. > > Reviews, comments and test reports are very welcome! > Please test the patch if you have any problems with how CPU topology is > reported > by the current code. Please test even if everything is OK, to avoid > regressions. -- Andriy Gapon _______________________________________________ freebsd-stable@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-stable To unsubscribe, send any mail to "freebsd-stable-unsubscr...@freebsd.org"
