[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>
diff --git a/arch/i386/kernel/mpparse.c b/arch/i386/kernel/mpparse.c
index ce838ab..788efff 100644
--- a/arch/i386/kernel/mpparse.c
+++ b/arch/i386/kernel/mpparse.c
@@ -65,6 +65,8 @@
int pic_mode;
unsigned long mp_lapic_addr;
+unsigned int def_to_bigsmp = 0;
+
/* Processor that is doing the boot up */
unsigned int boot_cpu_physical_apicid = -1U;
/* Internal processor count */
@@ -213,6 +215,13 @@
ver = 0x10;
}
apic_version[m->mpc_apicid] = ver;
+ if ((num_processors > 8) &&
+ APIC_XAPIC(ver) &&
+ (boot_cpu_data.x86_vendor == X86_VENDOR_INTEL))
+ def_to_bigsmp = 1;
+ else
+ def_to_bigsmp = 0;
+
bios_cpu_apicid[num_processors - 1] = m->mpc_apicid;
}