[PATCH 07/16] x86: Add apic->x86_32_early_logical_apicid()

From: Tejun Heo
Date: Tue Dec 28 2010 - 06:49:25 EST


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@xxxxxxxxxx>
---
arch/x86/include/asm/apic.h | 19 +++++++++++++++++++
arch/x86/kernel/apic/apic.c | 12 ++++++++++--
arch/x86/kernel/apic/apic_noop.c | 4 ++++
arch/x86/kernel/apic/bigsmp_32.c | 2 ++
arch/x86/kernel/apic/es7000_32.c | 4 ++++
arch/x86/kernel/apic/numaq_32.c | 2 ++
arch/x86/kernel/apic/probe_32.c | 2 ++
arch/x86/kernel/apic/summit_32.c | 2 ++
8 files changed, 45 insertions(+), 2 deletions(-)

diff --git a/arch/x86/include/asm/apic.h b/arch/x86/include/asm/apic.h
index d1aa0c3..efb073b 100644
--- a/arch/x86/include/asm/apic.h
+++ b/arch/x86/include/asm/apic.h
@@ -354,6 +354,20 @@ struct apic {
void (*icr_write)(u32 low, u32 high);
void (*wait_icr_idle)(void);
u32 (*safe_wait_icr_idle)(void);
+
+#ifdef CONFIG_X86_32
+ /*
+ * Called very early during boot from get_smp_config(). It should
+ * return the logical apicid. x86_[bios]_cpu_to_apicid is
+ * initialized before this function is called.
+ *
+ * If logical apicid can't be determined that early, the function
+ * may return BAD_APICID. Logical apicid will be configured after
+ * init_apic_ldr() while bringing up CPUs. Note that NUMA affinity
+ * won't be applied properly during early boot in this case.
+ */
+ int (*x86_32_early_logical_apicid)(int cpu);
+#endif
};

/*
@@ -501,6 +515,11 @@ extern struct apic apic_noop;

extern struct apic apic_default;

+static inline int noop_x86_32_early_logical_apicid(int cpu)
+{
+ return BAD_APICID;
+}
+
/*
* Set up the logical destination ID.
*
diff --git a/arch/x86/kernel/apic/apic.c b/arch/x86/kernel/apic/apic.c
index 8ad231c..6a82dc6 100644
--- a/arch/x86/kernel/apic/apic.c
+++ b/arch/x86/kernel/apic/apic.c
@@ -1254,8 +1254,13 @@ 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
@@ -1994,7 +1999,10 @@ 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 f3d19b2..0309c58 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 4c62592..dd32a9b 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 6840681..0ffc1ec 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 2b434d5..f1a8b12 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 24a6828..40be7c3 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 1ef4c14..172c498 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,
};
--
1.7.1

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