x86: Add apic->x86_32_early_logical_apicid()
On x86_32, the mapping between cpu and logical apic ID differs
depending on the specific apic implementation in use. The
mapping is initialized while bringing up CPUs; however, this
makes early inits ignore memory topology.
Add a x86_32 specific apic->x86_32_early_logical_apicid() which
is called early during boot to query the mapping. The mapping
is later verified against the result of init_apic_ldr(). The
method is allowed to return BAD_APICID if it can't be determined
early.
noop variant which always returns BAD_APICID is implemented and
added to all x86_32 apic implementations.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: eric.dumazet@gmail.com
Cc: yinghai@kernel.org
Cc: brgerst@gmail.com
Cc: gorcunov@gmail.com
Cc: penberg@kernel.org
Cc: shaohui.zheng@intel.com
Cc: rientjes@google.com
LKML-Reference: <1295789862-25482-8-git-send-email-tj@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/arch/x86/kernel/apic/apic.c b/arch/x86/kernel/apic/apic.c
index ae08246..3127079 100644
--- a/arch/x86/kernel/apic/apic.c
+++ b/arch/x86/kernel/apic/apic.c
@@ -1250,8 +1250,13 @@
#ifdef CONFIG_X86_32
/*
- * APIC LDR is initialized. Fetch and store logical_apic_id.
+ * APIC LDR is initialized. If logical_apicid mapping was
+ * initialized during get_smp_config(), make sure it matches the
+ * actual value.
*/
+ i = early_per_cpu(x86_cpu_to_logical_apicid, cpu);
+ WARN_ON(i != BAD_APICID && i != logical_smp_processor_id());
+ /* always use the value from LDR */
early_per_cpu(x86_cpu_to_logical_apicid, cpu) =
logical_smp_processor_id();
#endif
@@ -1991,7 +1996,10 @@
early_per_cpu(x86_cpu_to_apicid, cpu) = apicid;
early_per_cpu(x86_bios_cpu_apicid, cpu) = apicid;
#endif
-
+#ifdef CONFIG_X86_32
+ early_per_cpu(x86_cpu_to_logical_apicid, cpu) =
+ apic->x86_32_early_logical_apicid(cpu);
+#endif
set_cpu_possible(cpu, true);
set_cpu_present(cpu, true);
}