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>

7 files changed, 26 insertions, 2 deletions

diff --git a/arch/x86/kernel/apic/apic.c b/arch/x86/kernel/apic/apic.c
index ae08246f320c..3127079628e8 100644
--- a/arch/x86/kernel/apic/apic.c
+++ b/arch/x86/kernel/apic/apic.c
@@ -1250,8 +1250,13 @@ void __cpuinit setup_local_APIC(void)
 
 #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 @@ void __cpuinit generic_processor_info(int apicid, int version)
         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);
 }
diff --git a/arch/x86/kernel/apic/apic_noop.c b/arch/x86/kernel/apic/apic_noop.c
index f3d19b2426ab..0309c58d96bc 100644
--- a/arch/x86/kernel/apic/apic_noop.c
+++ b/arch/x86/kernel/apic/apic_noop.c
@@ -191,4 +191,8 @@ struct apic apic_noop = {
         .icr_write                      = noop_apic_icr_write,
         .wait_icr_idle                  = noop_apic_wait_icr_idle,
         .safe_wait_icr_idle             = noop_safe_apic_wait_icr_idle,
+
+#ifdef CONFIG_X86_32
+        .x86_32_early_logical_apicid    = noop_x86_32_early_logical_apicid,
+#endif
 };
diff --git a/arch/x86/kernel/apic/bigsmp_32.c b/arch/x86/kernel/apic/bigsmp_32.c
index 4c62592d6869..dd32a9b78a87 100644
--- a/arch/x86/kernel/apic/bigsmp_32.c
+++ b/arch/x86/kernel/apic/bigsmp_32.c
@@ -251,4 +251,6 @@ struct apic apic_bigsmp = {
         .icr_write                      = native_apic_icr_write,
         .wait_icr_idle                  = native_apic_wait_icr_idle,
         .safe_wait_icr_idle             = native_safe_apic_wait_icr_idle,
+
+        .x86_32_early_logical_apicid    = noop_x86_32_early_logical_apicid,
 };
diff --git a/arch/x86/kernel/apic/es7000_32.c b/arch/x86/kernel/apic/es7000_32.c
index 6840681a3f14..0ffc1eca5777 100644
--- a/arch/x86/kernel/apic/es7000_32.c
+++ b/arch/x86/kernel/apic/es7000_32.c
@@ -682,6 +682,8 @@ struct apic __refdata apic_es7000_cluster = {
         .icr_write                      = native_apic_icr_write,
         .wait_icr_idle                  = native_apic_wait_icr_idle,
         .safe_wait_icr_idle             = native_safe_apic_wait_icr_idle,
+
+        .x86_32_early_logical_apicid    = noop_x86_32_early_logical_apicid,
 };
 
 struct apic __refdata apic_es7000 = {
@@ -744,4 +746,6 @@ struct apic __refdata apic_es7000 = {
         .icr_write                      = native_apic_icr_write,
         .wait_icr_idle                  = native_apic_wait_icr_idle,
         .safe_wait_icr_idle             = native_safe_apic_wait_icr_idle,
+
+        .x86_32_early_logical_apicid    = noop_x86_32_early_logical_apicid,
 };
diff --git a/arch/x86/kernel/apic/numaq_32.c b/arch/x86/kernel/apic/numaq_32.c
index 2b434d579e15..f1a8b120c49d 100644
--- a/arch/x86/kernel/apic/numaq_32.c
+++ b/arch/x86/kernel/apic/numaq_32.c
@@ -539,4 +539,6 @@ struct apic __refdata apic_numaq = {
         .icr_write                      = native_apic_icr_write,
         .wait_icr_idle                  = native_apic_wait_icr_idle,
         .safe_wait_icr_idle             = native_safe_apic_wait_icr_idle,
+
+        .x86_32_early_logical_apicid    = noop_x86_32_early_logical_apicid,
 };
diff --git a/arch/x86/kernel/apic/probe_32.c b/arch/x86/kernel/apic/probe_32.c
index 24a68281101b..40be7c3cdfeb 100644
--- a/arch/x86/kernel/apic/probe_32.c
+++ b/arch/x86/kernel/apic/probe_32.c
@@ -166,6 +166,8 @@ struct apic apic_default = {
         .icr_write                      = native_apic_icr_write,
         .wait_icr_idle                  = native_apic_wait_icr_idle,
         .safe_wait_icr_idle             = native_safe_apic_wait_icr_idle,
+
+        .x86_32_early_logical_apicid    = noop_x86_32_early_logical_apicid,
 };
 
 extern struct apic apic_numaq;
diff --git a/arch/x86/kernel/apic/summit_32.c b/arch/x86/kernel/apic/summit_32.c
index 1ef4c14f4d6b..172c498e888f 100644
--- a/arch/x86/kernel/apic/summit_32.c
+++ b/arch/x86/kernel/apic/summit_32.c
@@ -552,4 +552,6 @@ struct apic apic_summit = {
         .icr_write                      = native_apic_icr_write,
         .wait_icr_idle                  = native_apic_wait_icr_idle,
         .safe_wait_icr_idle             = native_safe_apic_wait_icr_idle,
+
+        .x86_32_early_logical_apicid    = noop_x86_32_early_logical_apicid,
 };