From: Ravikiran G Thirumalai Date: Sat, 25 Mar 2006 15:30:04 +0000 (+0100) Subject: [PATCH] x86_64: to use lapic ids instead of initial apic ids X-Git-Tag: v3.12-rc1~37528 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=60c1bc82d9d42486e2b96de668b0b49fadaffd12;p=kernel%2Fkernel-generic.git [PATCH] x86_64: to use lapic ids instead of initial apic ids phys_proc_id[] on AMD boxes is right now populated with the initial apic id, obtained by the cpuid instruction. But, the initial apic id need not be the local apic id on clustered APIC systems (see comment at x86_64/kernel/genapic_cluster.c, line 110). On vSMPowered with AMD CPUs the cpu_to_node will turn out to be incorrect (as apicid_to_node[] is indexed by the initial apic id rather than the local apic id). On vSMPowered boxes with Intel CPUs this is working correctly as phys_proc_id[] is initialized correctly in detect_ht(). This fixes AMD boot path according to specification, to use the correct routines for local apic id and socket ids. We use hard_smp_processor_id() to read the local apic id, and phys_pkg_id() to determine socket id for phys_proc_id[] Patch tested on Tyan multicore boxes as well as vSMPowered boxes. Signed-off-by: Ravikiran Thirumalai Signed-off-by: Shai Fultheim Signed-off-by: Andi Kleen Signed-off-by: Linus Torvalds --- diff --git a/arch/x86_64/kernel/setup.c b/arch/x86_64/kernel/setup.c index ad3b7fc..49f2858 100644 --- a/arch/x86_64/kernel/setup.c +++ b/arch/x86_64/kernel/setup.c @@ -846,7 +846,7 @@ static void __init amd_detect_cmp(struct cpuinfo_x86 *c) unsigned bits; #ifdef CONFIG_NUMA int node = 0; - unsigned apicid = phys_proc_id[cpu]; + unsigned apicid = hard_smp_processor_id(); #endif bits = 0; @@ -856,7 +856,7 @@ static void __init amd_detect_cmp(struct cpuinfo_x86 *c) /* Low order bits define the core id (index of core in socket) */ cpu_core_id[cpu] = phys_proc_id[cpu] & ((1 << bits)-1); /* Convert the APIC ID into the socket ID */ - phys_proc_id[cpu] >>= bits; + phys_proc_id[cpu] = phys_pkg_id(bits); #ifdef CONFIG_NUMA node = phys_proc_id[cpu];