From: Natalie.Protasevich@unisys.com This patch is per Andi's request to remove NO_IOAPIC_CHECK from genapic and use heuristics to prevent unique I/O APIC ID check for systems that don't need it. The patch disables unique I/O APIC ID check for Xeon-based and other platforms that don't use serial APIC bus for interrupt delivery. Andi stated that AMD systems don't need unique IO_APIC_IDs either. Signed-off-by: Natalie Protasevich Cc: Andi Kleen Signed-off-by: Andrew Morton --- arch/i386/kernel/io_apic.c | 10 ++++++---- arch/i386/kernel/mpparse.c | 5 ++++- include/asm-i386/genapic.h | 1 - include/asm-i386/mach-bigsmp/mach_apic.h | 2 -- include/asm-i386/mach-default/mach_apic.h | 2 -- include/asm-i386/mach-es7000/mach_apic.h | 2 -- include/asm-i386/mach-generic/mach_apic.h | 1 - include/asm-i386/mach-numaq/mach_apic.h | 2 -- include/asm-i386/mach-summit/mach_apic.h | 2 -- include/asm-i386/mach-visws/mach_apic.h | 2 -- 10 files changed, 10 insertions(+), 19 deletions(-) diff -puN arch/i386/kernel/io_apic.c~do-not-enforce-unique-io_apic_id-check-for-xapic-systems-i386 arch/i386/kernel/io_apic.c --- 25/arch/i386/kernel/io_apic.c~do-not-enforce-unique-io_apic_id-check-for-xapic-systems-i386 2005-05-12 01:21:39.000000000 -0700 +++ 25-akpm/arch/i386/kernel/io_apic.c 2005-05-12 01:21:39.000000000 -0700 @@ -1659,6 +1659,12 @@ static void __init setup_ioapic_ids_from unsigned long flags; /* + * Don't check I/O APIC IDs for xAPIC systems. They have + * no meaning without the serial APIC bus. + */ + if (!(boot_cpu_data.x86_vendor == X86_VENDOR_INTEL && boot_cpu_data.x86 < 15)) + return; + /* * This is broken; anything with a real cpu count has to * circumvent this idiocy regardless. */ @@ -1684,10 +1690,6 @@ static void __init setup_ioapic_ids_from mp_ioapics[apic].mpc_apicid = reg_00.bits.ID; } - /* Don't check I/O APIC IDs for some xAPIC systems. They have - * no meaning without the serial APIC bus. */ - if (NO_IOAPIC_CHECK) - continue; /* * Sanity check, is the ID really free? Every APIC in a * system must have a unique ID or we get lots of nice diff -puN arch/i386/kernel/mpparse.c~do-not-enforce-unique-io_apic_id-check-for-xapic-systems-i386 arch/i386/kernel/mpparse.c --- 25/arch/i386/kernel/mpparse.c~do-not-enforce-unique-io_apic_id-check-for-xapic-systems-i386 2005-05-12 01:21:39.000000000 -0700 +++ 25-akpm/arch/i386/kernel/mpparse.c 2005-05-12 01:21:39.000000000 -0700 @@ -914,7 +914,10 @@ void __init mp_register_ioapic ( mp_ioapics[idx].mpc_apicaddr = address; set_fixmap_nocache(FIX_IO_APIC_BASE_0 + idx, address); - mp_ioapics[idx].mpc_apicid = io_apic_get_unique_id(idx, id); + if ((boot_cpu_data.x86_vendor == X86_VENDOR_INTEL) && (boot_cpu_data.x86 < 15)) + mp_ioapics[idx].mpc_apicid = io_apic_get_unique_id(idx, id); + else + mp_ioapics[idx].mpc_apicid = id; mp_ioapics[idx].mpc_apicver = io_apic_get_version(idx); /* diff -puN include/asm-i386/genapic.h~do-not-enforce-unique-io_apic_id-check-for-xapic-systems-i386 include/asm-i386/genapic.h --- 25/include/asm-i386/genapic.h~do-not-enforce-unique-io_apic_id-check-for-xapic-systems-i386 2005-05-12 01:21:39.000000000 -0700 +++ 25-akpm/include/asm-i386/genapic.h 2005-05-12 01:21:39.000000000 -0700 @@ -78,7 +78,6 @@ struct genapic { .int_delivery_mode = INT_DELIVERY_MODE, \ .int_dest_mode = INT_DEST_MODE, \ .no_balance_irq = NO_BALANCE_IRQ, \ - .no_ioapic_check = NO_IOAPIC_CHECK, \ .ESR_DISABLE = esr_disable, \ .apic_destination_logical = APIC_DEST_LOGICAL, \ APICFUNC(apic_id_registered), \ diff -puN include/asm-i386/mach-bigsmp/mach_apic.h~do-not-enforce-unique-io_apic_id-check-for-xapic-systems-i386 include/asm-i386/mach-bigsmp/mach_apic.h --- 25/include/asm-i386/mach-bigsmp/mach_apic.h~do-not-enforce-unique-io_apic_id-check-for-xapic-systems-i386 2005-05-12 01:21:39.000000000 -0700 +++ 25-akpm/include/asm-i386/mach-bigsmp/mach_apic.h 2005-05-12 01:21:39.000000000 -0700 @@ -14,8 +14,6 @@ #define NO_BALANCE_IRQ (1) #define esr_disable (1) -#define NO_IOAPIC_CHECK (0) - static inline int apic_id_registered(void) { return (1); diff -puN include/asm-i386/mach-default/mach_apic.h~do-not-enforce-unique-io_apic_id-check-for-xapic-systems-i386 include/asm-i386/mach-default/mach_apic.h --- 25/include/asm-i386/mach-default/mach_apic.h~do-not-enforce-unique-io_apic_id-check-for-xapic-systems-i386 2005-05-12 01:21:39.000000000 -0700 +++ 25-akpm/include/asm-i386/mach-default/mach_apic.h 2005-05-12 01:21:39.000000000 -0700 @@ -19,8 +19,6 @@ static inline cpumask_t target_cpus(void #define NO_BALANCE_IRQ (0) #define esr_disable (0) -#define NO_IOAPIC_CHECK (0) - #define INT_DELIVERY_MODE dest_LowestPrio #define INT_DEST_MODE 1 /* logical delivery broadcast to all procs */ diff -puN include/asm-i386/mach-es7000/mach_apic.h~do-not-enforce-unique-io_apic_id-check-for-xapic-systems-i386 include/asm-i386/mach-es7000/mach_apic.h --- 25/include/asm-i386/mach-es7000/mach_apic.h~do-not-enforce-unique-io_apic_id-check-for-xapic-systems-i386 2005-05-12 01:21:39.000000000 -0700 +++ 25-akpm/include/asm-i386/mach-es7000/mach_apic.h 2005-05-12 01:21:39.000000000 -0700 @@ -38,8 +38,6 @@ static inline cpumask_t target_cpus(void #define WAKE_SECONDARY_VIA_INIT #endif -#define NO_IOAPIC_CHECK (1) - static inline unsigned long check_apicid_used(physid_mask_t bitmap, int apicid) { return 0; diff -puN include/asm-i386/mach-generic/mach_apic.h~do-not-enforce-unique-io_apic_id-check-for-xapic-systems-i386 include/asm-i386/mach-generic/mach_apic.h --- 25/include/asm-i386/mach-generic/mach_apic.h~do-not-enforce-unique-io_apic_id-check-for-xapic-systems-i386 2005-05-12 01:21:39.000000000 -0700 +++ 25-akpm/include/asm-i386/mach-generic/mach_apic.h 2005-05-12 01:21:39.000000000 -0700 @@ -5,7 +5,6 @@ #define esr_disable (genapic->ESR_DISABLE) #define NO_BALANCE_IRQ (genapic->no_balance_irq) -#define NO_IOAPIC_CHECK (genapic->no_ioapic_check) #define INT_DELIVERY_MODE (genapic->int_delivery_mode) #define INT_DEST_MODE (genapic->int_dest_mode) #undef APIC_DEST_LOGICAL diff -puN include/asm-i386/mach-numaq/mach_apic.h~do-not-enforce-unique-io_apic_id-check-for-xapic-systems-i386 include/asm-i386/mach-numaq/mach_apic.h --- 25/include/asm-i386/mach-numaq/mach_apic.h~do-not-enforce-unique-io_apic_id-check-for-xapic-systems-i386 2005-05-12 01:21:39.000000000 -0700 +++ 25-akpm/include/asm-i386/mach-numaq/mach_apic.h 2005-05-12 01:21:39.000000000 -0700 @@ -17,8 +17,6 @@ static inline cpumask_t target_cpus(void #define NO_BALANCE_IRQ (1) #define esr_disable (1) -#define NO_IOAPIC_CHECK (0) - #define INT_DELIVERY_MODE dest_LowestPrio #define INT_DEST_MODE 0 /* physical delivery on LOCAL quad */ diff -puN include/asm-i386/mach-summit/mach_apic.h~do-not-enforce-unique-io_apic_id-check-for-xapic-systems-i386 include/asm-i386/mach-summit/mach_apic.h --- 25/include/asm-i386/mach-summit/mach_apic.h~do-not-enforce-unique-io_apic_id-check-for-xapic-systems-i386 2005-05-12 01:21:39.000000000 -0700 +++ 25-akpm/include/asm-i386/mach-summit/mach_apic.h 2005-05-12 01:21:39.000000000 -0700 @@ -7,8 +7,6 @@ #define esr_disable (1) #define NO_BALANCE_IRQ (0) -#define NO_IOAPIC_CHECK (1) /* Don't check I/O APIC ID for xAPIC */ - /* In clustered mode, the high nibble of APIC ID is a cluster number. * The low nibble is a 4-bit bitmap. */ #define XAPIC_DEST_CPUS_SHIFT 4 diff -puN include/asm-i386/mach-visws/mach_apic.h~do-not-enforce-unique-io_apic_id-check-for-xapic-systems-i386 include/asm-i386/mach-visws/mach_apic.h --- 25/include/asm-i386/mach-visws/mach_apic.h~do-not-enforce-unique-io_apic_id-check-for-xapic-systems-i386 2005-05-12 01:21:39.000000000 -0700 +++ 25-akpm/include/asm-i386/mach-visws/mach_apic.h 2005-05-12 01:21:39.000000000 -0700 @@ -9,8 +9,6 @@ #define no_balance_irq (0) #define esr_disable (0) -#define NO_IOAPIC_CHECK (0) - #define INT_DELIVERY_MODE dest_LowestPrio #define INT_DEST_MODE 1 /* logical delivery broadcast to all procs */ _