x86: Set cpu_llc_id on AMD CPUs
commit 99bd0c0f upstream. This counts when building sched domains in case NUMA information is not available. ( See cpu_coregroup_mask() which uses llc_shared_map which in turn is created based on cpu_llc_id. ) Currently Linux builds domains as follows: (example from a dual socket quad-core system) CPU0 attaching sched-domain: domain 0: span 0-7 level CPU groups: 0 1 2 3 4 5 6 7 ... CPU7 attaching sched-domain: domain 0: span 0-7 level CPU groups: 7 0 1 2 3 4 5 6 Ever since that is borked for multi-core AMD CPU systems. This patch fixes that and now we get a proper: CPU0 attaching sched-domain: domain 0: span 0-3 level MC groups: 0 1 2 3 domain 1: span 0-7 level CPU groups: 0-3 4-7 ... CPU7 attaching sched-domain: domain 0: span 4-7 level MC groups: 7 4 5 6 domain 1: span 0-7 level CPU groups: 4-7 0-3 This allows scheduler to assign tasks to cores on different sockets (i.e. that don't share last level cache) for performance reasons. Signed-off-by:Andreas Herrmann <andreas.herrmann3@amd.com> LKML-Reference: <20090619085909.GJ5218@alberich.amd.com> Signed-off-by:
Ingo Molnar <mingo@elte.hu> Signed-off-by:
Greg Kroah-Hartman <gregkh@suse.de>
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