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| author | Fernando Luis Vazquez Cao <fernando@oss.ntt.co.jp> | 2007-05-09 02:33:27 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@woody.linux-foundation.org> | 2007-05-09 12:30:48 -0700 |
| commit | a36166c6ef45081fea6eeaf5ca785d7ed786b6e2 (patch) | |
| tree | bdb5a99e3c80883cbb84d6e190b4dabefec79032 /include | |
| parent | 2f4dfe206a2fc07099dfad77a8ea2f4b4ae2140f (diff) | |
| download | op-kernel-dev-a36166c6ef45081fea6eeaf5ca785d7ed786b6e2.zip op-kernel-dev-a36166c6ef45081fea6eeaf5ca785d7ed786b6e2.tar.gz | |
Use the APIC to determine the hardware processor id - i386
hard_smp_processor_id used to be just a macro that hard-coded
hard_smp_processor_id to 0 in the non SMP case. When booting non SMP kernels
on hardware where the boot ioapic id is not 0 this turns out to be a problem.
This is happens frequently in the case of kdump and once in a great while in
the case of real hardware.
Use the APIC to determine the hardware processor id in both UP and SMP kernels
to fix this issue.
Notice that hard_smp_processor_id is only used by SMP code or by code that
works with apics so we do not need to handle the case when apics are not
present and hard_smp_processor_id should never be called there.
Signed-off-by: Fernando Luis Vazquez Cao <fernando@oss.ntt.co.jp>
Cc: "Luck, Tony" <tony.luck@intel.com>
Acked-by: Andi Kleen <ak@suse.de>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Vivek Goyal <vgoyal@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'include')
| -rw-r--r-- | include/asm-i386/smp.h | 36 |
1 files changed, 21 insertions, 15 deletions
diff --git a/include/asm-i386/smp.h b/include/asm-i386/smp.h index 3243fa6..0c71327 100644 --- a/include/asm-i386/smp.h +++ b/include/asm-i386/smp.h @@ -124,20 +124,6 @@ static inline int num_booting_cpus(void) return cpus_weight(cpu_callout_map); } -#ifdef CONFIG_X86_LOCAL_APIC - -#ifdef APIC_DEFINITION -extern int hard_smp_processor_id(void); -#else -#include <mach_apicdef.h> -static inline int hard_smp_processor_id(void) -{ - /* we don't want to mark this access volatile - bad code generation */ - return GET_APIC_ID(*(unsigned long *)(APIC_BASE+APIC_ID)); -} -#endif -#endif - extern int safe_smp_processor_id(void); extern int __cpu_disable(void); extern void __cpu_die(unsigned int cpu); @@ -147,7 +133,6 @@ extern unsigned int num_processors; #else /* CONFIG_SMP */ -#define hard_smp_processor_id() 0 #define safe_smp_processor_id() 0 #define cpu_physical_id(cpu) boot_cpu_physical_apicid @@ -157,6 +142,27 @@ extern unsigned int num_processors; #ifndef __ASSEMBLY__ +#ifdef CONFIG_X86_LOCAL_APIC + +#ifdef APIC_DEFINITION +extern int hard_smp_processor_id(void); +#else +#include <mach_apicdef.h> +static inline int hard_smp_processor_id(void) +{ + /* we don't want to mark this access volatile - bad code generation */ + return GET_APIC_ID(*(unsigned long *)(APIC_BASE+APIC_ID)); +} +#endif /* APIC_DEFINITION */ + +#else /* CONFIG_X86_LOCAL_APIC */ + +#ifndef CONFIG_SMP +#define hard_smp_processor_id() 0 +#endif + +#endif /* CONFIG_X86_LOCAL_APIC */ + extern u8 apicid_2_node[]; #ifdef CONFIG_X86_LOCAL_APIC |
