[PATCH] x86: sutomatically enable bigsmp when we have more than 8 CPUs

i386 generic subarchitecture requires explicit dmi strings or command line
to enable bigsmp mode.  The patch below removes that restriction, and uses
bigsmp as soon as it finds more than 8 logical CPUs, Intel processors and
xAPIC support.

Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

3 files changed, 4 insertions, 0 deletions

diff --git a/include/asm-i386/apicdef.h b/include/asm-i386/apicdef.h
index a96a8f48fbfc..03185cef8e0a 100644
--- a/include/asm-i386/apicdef.h
+++ b/include/asm-i386/apicdef.h
@@ -16,6 +16,7 @@
 #define                 GET_APIC_VERSION(x)     ((x)&0xFF)
 #define                 GET_APIC_MAXLVT(x)      (((x)>>16)&0xFF)
 #define                 APIC_INTEGRATED(x)      ((x)&0xF0)
+#define                 APIC_XAPIC(x)           ((x) >= 0x14)
 #define         APIC_TASKPRI    0x80
 #define                 APIC_TPRI_MASK          0xFF
 #define         APIC_ARBPRI     0x90
diff --git a/include/asm-i386/mach-generic/mach_apic.h b/include/asm-i386/mach-generic/mach_apic.h
index b13767a4e934..d9dc039da94a 100644
--- a/include/asm-i386/mach-generic/mach_apic.h
+++ b/include/asm-i386/mach-generic/mach_apic.h
@@ -28,4 +28,6 @@
 #define enable_apic_mode (genapic->enable_apic_mode)
 #define phys_pkg_id (genapic->phys_pkg_id)
 
+extern void generic_bigsmp_probe(void);
+
 #endif /* __ASM_MACH_APIC_H */
diff --git a/include/asm-i386/mpspec.h b/include/asm-i386/mpspec.h
index d9fafba075bc..d84a9c326c22 100644
--- a/include/asm-i386/mpspec.h
+++ b/include/asm-i386/mpspec.h
@@ -11,6 +11,7 @@ extern int mp_bus_id_to_local [MAX_MP_BUSSES];
 extern int quad_local_to_mp_bus_id [NR_CPUS/4][4];
 extern int mp_bus_id_to_pci_bus [MAX_MP_BUSSES];
 
+extern unsigned int def_to_bigsmp;
 extern unsigned int boot_cpu_physical_apicid;
 extern int smp_found_config;
 extern void find_smp_config (void);