From 90af668a965fd4732996274c7babfc63b090ddf0 Mon Sep 17 00:00:00 2001
From: Yinghai Lu <yhlu.kernel@gmail.com>
Date: Fri, 12 Sep 2008 13:08:18 +0200
Subject: [PATCH] APIC routing fix

commit e0da33646826b66ef933d47ea2fb7a693fd849bf upstream

x86: introduce max_physical_apicid for bigsmp switching

a multi-socket test-system with 3 or 4 ioapics, when 4 dualcore cpus or
2 quadcore cpus installed, needs to switch to bigsmp or physflat.

CPU apic id is [4,11] instead of [0,7], and we need to check max apic
id instead of cpu numbers.

also add check for 32 bit when acpi is not compiled in or acpi=off.

Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
---
 arch/x86/kernel/apic_32.c      |  5 ++++-
 arch/x86/kernel/apic_64.c      |  3 +++
 arch/x86/kernel/genapic_64.c   |  2 +-
 arch/x86/kernel/mpparse.c      |  5 +++++
 arch/x86/kernel/setup.c        |  1 +
 arch/x86/kernel/setup_32.c     | 11 ++++++-----
 arch/x86/mach-generic/bigsmp.c |  2 +-
 include/asm-x86/mpspec.h       |  1 +
 8 files changed, 22 insertions(+), 8 deletions(-)

diff --git a/arch/x86/kernel/apic_32.c b/arch/x86/kernel/apic_32.c
index 6815189e845..c17fdb0b709 100644
--- a/arch/x86/kernel/apic_32.c
+++ b/arch/x86/kernel/apic_32.c
@@ -1536,6 +1536,9 @@ void __cpuinit generic_processor_info(int apicid, int version)
 		 */
 		cpu = 0;
 
+	if (apicid > max_physical_apicid)
+		max_physical_apicid = apicid;
+
 	/*
 	 * Would be preferable to switch to bigsmp when CONFIG_HOTPLUG_CPU=y
 	 * but we need to work other dependencies like SMP_SUSPEND etc
@@ -1543,7 +1546,7 @@ void __cpuinit generic_processor_info(int apicid, int version)
 	 * if (CPU_HOTPLUG_ENABLED || num_processors > 8)
 	 *       - Ashok Raj <ashok.raj@intel.com>
 	 */
-	if (num_processors > 8) {
+	if (max_physical_apicid >= 8) {
 		switch (boot_cpu_data.x86_vendor) {
 		case X86_VENDOR_INTEL:
 			if (!APIC_XAPIC(version)) {
diff --git a/arch/x86/kernel/apic_64.c b/arch/x86/kernel/apic_64.c
index 0633cfd0dc2..8472bdfd523 100644
--- a/arch/x86/kernel/apic_64.c
+++ b/arch/x86/kernel/apic_64.c
@@ -1090,6 +1090,9 @@ void __cpuinit generic_processor_info(int apicid, int version)
 		 */
 		cpu = 0;
 	}
+	if (apicid > max_physical_apicid)
+		max_physical_apicid = apicid;
+
 	/* are we being called early in kernel startup? */
 	if (x86_cpu_to_apicid_early_ptr) {
 		u16 *cpu_to_apicid = x86_cpu_to_apicid_early_ptr;
diff --git a/arch/x86/kernel/genapic_64.c b/arch/x86/kernel/genapic_64.c
index cbaaf69bedb..1fa8be5bd21 100644
--- a/arch/x86/kernel/genapic_64.c
+++ b/arch/x86/kernel/genapic_64.c
@@ -51,7 +51,7 @@ void __init setup_apic_routing(void)
 	else
 #endif
 
-	if (num_possible_cpus() <= 8)
+	if (max_physical_apicid < 8)
 		genapic = &apic_flat;
 	else
 		genapic = &apic_physflat;
diff --git a/arch/x86/kernel/mpparse.c b/arch/x86/kernel/mpparse.c
index 404683b94e7..d5b8691fff4 100644
--- a/arch/x86/kernel/mpparse.c
+++ b/arch/x86/kernel/mpparse.c
@@ -402,6 +402,11 @@ static int __init smp_read_mpc(struct mp_config_table *mpc, unsigned early)
 		++mpc_record;
 #endif
 	}
+
+#ifdef CONFIG_X86_GENERICARCH
+       generic_bigsmp_probe();
+#endif
+
 	setup_apic_routing();
 	if (!num_processors)
 		printk(KERN_ERR "MPTABLE: no processors registered!\n");
diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
index 6f80b852a19..03e357a1954 100644
--- a/arch/x86/kernel/setup.c
+++ b/arch/x86/kernel/setup.c
@@ -17,6 +17,7 @@ unsigned int num_processors;
 unsigned disabled_cpus __cpuinitdata;
 /* Processor that is doing the boot up */
 unsigned int boot_cpu_physical_apicid = -1U;
+unsigned int max_physical_apicid;
 EXPORT_SYMBOL(boot_cpu_physical_apicid);
 
 DEFINE_PER_CPU(u16, x86_cpu_to_apicid) = BAD_APICID;
diff --git a/arch/x86/kernel/setup_32.c b/arch/x86/kernel/setup_32.c
index 5a2f8e06388..3bf22f030d7 100644
--- a/arch/x86/kernel/setup_32.c
+++ b/arch/x86/kernel/setup_32.c
@@ -914,6 +914,12 @@ void __init setup_arch(char **cmdline_p)
 
 #ifdef CONFIG_ACPI
 	acpi_boot_init();
+#endif
+
+#ifdef CONFIG_X86_LOCAL_APIC
+	if (smp_found_config)
+		get_smp_config();
+#endif
 
 #if defined(CONFIG_SMP) && defined(CONFIG_X86_PC)
 	if (def_to_bigsmp)
@@ -921,11 +927,6 @@ void __init setup_arch(char **cmdline_p)
 			"CONFIG_X86_PC cannot handle it.\nUse "
 			"CONFIG_X86_GENERICARCH or CONFIG_X86_BIGSMP.\n");
 #endif
-#endif
-#ifdef CONFIG_X86_LOCAL_APIC
-	if (smp_found_config)
-		get_smp_config();
-#endif
 
 	e820_register_memory();
 	e820_mark_nosave_regions();
diff --git a/arch/x86/mach-generic/bigsmp.c b/arch/x86/mach-generic/bigsmp.c
index 95fc463056d..2a243019aca 100644
--- a/arch/x86/mach-generic/bigsmp.c
+++ b/arch/x86/mach-generic/bigsmp.c
@@ -48,7 +48,7 @@ static const struct dmi_system_id bigsmp_dmi_table[] = {
 static int probe_bigsmp(void)
 {
 	if (def_to_bigsmp)
-	dmi_bigsmp = 1;
+		dmi_bigsmp = 1;
 	else
 		dmi_check_system(bigsmp_dmi_table);
 	return dmi_bigsmp;
diff --git a/include/asm-x86/mpspec.h b/include/asm-x86/mpspec.h
index 57a991b9c05..4c7558731a3 100644
--- a/include/asm-x86/mpspec.h
+++ b/include/asm-x86/mpspec.h
@@ -35,6 +35,7 @@ extern DECLARE_BITMAP(mp_bus_not_pci, MAX_MP_BUSSES);
 extern int mp_bus_id_to_pci_bus[MAX_MP_BUSSES];
 
 extern unsigned int boot_cpu_physical_apicid;
+extern unsigned int max_physical_apicid;
 extern int smp_found_config;
 extern int mpc_default_type;
 extern unsigned long mp_lapic_addr;
-- 
2.25.4